Marine Life Society of South Australia Inc.
On Some South Australian Caulerpa Species
Preliminary Field Observations of Mating and Spawning in the Squid Sepioteuthis australis
More Nudibranch Discoveries
Recent Requests to Our Society for Information
Further Recent Requests to Our Society for Information
EDITORIAL - Philip Hall
Welcome to the 2005 edition of the MLSSA Journal. As usual this replaces the December monthly Newsletter.
This edition of the Journal starts with an article containing a somewhat controversial view of the benefits of Caulerpa taxifolia by MLSSA member Brian Brock.
The third and final part of the squid series of articles we have printed over the past two years by Troy Jantzen and Jon Havenhand follows.
Steve Reynolds contributes a beautifully illustrated article on local nudibranchs and follows with an article on information requests received by the Society.
I have added a second part to the information requests with some that I have answered.
The opinions expressed by authors of material published in this Journal are not necessarily those of the Society.
EDITING: Philip Hall
PRINTING: Phill McPeake
CONTRIBUTORS: Brian Brock
Troy Jantzen &
PHOTOGRAPHY: Dennis Hutson
by B. J. Brock BSc, Dip Sec Ed, MSc, FRSSA, MAI Biol
The genus Caulerpa includes a large number of bright green stoloniferous algae bearing erect axes from which small side-branches called ramuli arise. The size, shape and arrangement of the ramuli on the axes, aids in the identification of the species. Fine root-like structures called rhizoids attach the stolons to the substrate. In some species, the primary axis branches and the branches also have ramuli on them. Refer to Womersley’s habit photographs and drawings of ramuli, and descriptions etc. if you wish to try your hand at keying out species (Womersley H. B. S.; 1984, pp. 253-274)
Drift specimens of Caulerpa may be found on many of our beaches after storms. Shepherd and Womersley (1970) record summer shedding of fronds of two Caulerpa species, leaving persistent stolons. Some species may be found attached in Intertidal pools or in the upper sub-littoral. A few species occur over a considerable range of depths. Caulerpa cactoides is a fairly robust species with clavate ramuli. Fragments of it are quite often washed up after storms, and I have seen it growing in several places in the upper sub-littoral zone (Port Douglas near Coffin Bay, Marion Bay, Groper Bay near Pondalowie, Marino Rocks, Edithburgh) and thought of it as a fairly shallow-water species. However, systematic collecting on the Nuyts Archipelago found it in the 32-38 metre zone and also at 2 metres in a sheltered site (See: Shepherd S. A. and Womersley H. B. S., 1976, p.188). Lucas (1936) p.48 records it “from low water mark to a depth of several fathoms”.
The Port Douglas form of Caulerpa cactoides differs from the Marion Bay form. One illustration accompanying this article is a photo-copy of a herbarium sheet prepared from a specimen collected from the blue-line off the Investigator Base Campsite near Black Springs (ANZSES Expedition) by Lynn Brake on 30/12/83.
Port Douglas form of C. cactoides
Compare it with the Marion Bay form.
Robust Marion Bay form of C. cactoides
Another species with a wide range of depth distribution is Caulerpa scalpelliformis. The scuba divers collected it on the four different transects in the St Francis group of islands at depths from 2-35 metres (Shepherd and Womersley 1976). I found it upper sub-littoral at the base of calcareous and harder metamorphic rocks near the Black Springs base camp. In this situation, it had to tolerate underwater sandstorms when there was much wave action. It could be confused with C. taxifolia but the ramuli in C. taxifolia are in opposite pairs (see Pic 3) while those of C. scalpelliformis alternate along the axis. The shapes of the ramuli also differ slightly in the two species. Refer to the West Island, Pearson Island and St Francis papers for accounts of algal ecology.
C. taxifolia from Angas Inlet.
Ramuli in opposite pairs on erect fronds.
Caulerpa trifaria is a fairly delicate Caulerpa species that used to be popular in marine aquaria. Three rows of fine ramuli run up the erect axes. The photo (Pic 4) shows the habit of a specimen collected at West Beach in 1975 by my daughter. Fresh drift specimens of marine algae can be rinsed in fresh water and floated out on cartridge paper. Dry between newspapers under weight. Muslin over the specimen will prevent it from sticking to the newspaper, but papers must be changed frequently to avoid mildew. Some dry reds are beautiful (Pic 5) and keep for years, especially if stored in a cool, dry, dark place.
C. trifaria has three rows of fine ramuli.
A herbarium sheet of the lovely red alga Kallymenia tasmanica
Caulerpa taxifolia (Aquarium Weed), is the species that initiated the battle to contain it in West Lakes. That battle has been lost. Like Barley Grass and other weeds on land, I think we will have to learn to live with it (and be thankful that it is a photosynthetic organism that fixes a lot of solar energy that passes on down whatever food chains). Some time ago, I saw what I thought might be Caulerpa taxifolia growing near an old dead mangrove tree lying near the end of the Fishermen’s jetty in the Angas Inlet. On 8/8/05, I decided to check it out more closely, from the shore. It had gone, but just around the corner, in a small inlet, was a knee-deep patch of suspicious-looking weed. I know this inlet well because I used to find the upside-down jellyfish Cassiopea ndrosia (Plates 15,3 and 15,4 of Shepherd and Thomas 1982) here in thousands before the blooms of red tide organisms began. The floor of the little inlet, used to be bare of weeds. A sample of the weed-patch proved it to be a mix of Caulerpa taxifolia and a recently introduced Western Australian species called Caulerpa racemosa (see p. 270 and fig 91B of Womersley H. B. S. 1984; also the photo Pic 6 P 10 accompanying this article). I believe a similar mixed crop of weeds is found along the Port River side of Torrens Island. This is not surprising considering the way water circulates around Garden Island on the ebb and flow of the tides. (Cold water from North Arm is used for cooling purposes by the Torrens Island Power Station.) North Arm and Torrens Island are connected by a causeway that separates the cold North Arm waters from the warm effluent discharged into Angas Inlet. In times of peak demand, remote sensing of surface water temperature (Thomas et al. 1986 fig.4) shows that some of the warm effluent completely circles Garden Island. The warm effluent affects the distribution and abundance (Thomas I. M. et al., 1986) and seasons of settlement (Brock B. J. Unpublished M.Sc. thesis; and 1985) of some marine invertebrate species.
I collected Caulerpa racemosa and an Ulva species from the upper sublittoral in a mooring basin at the junction of the Port River and North Arm (near the open air produce market) on 24/3/04. I was able to key out the Caulerpa as C. racemosa using Womersley (1984). Bob Baldock of the State Herbarium, verified my identification on 26/3/04 and told me he had seen it on a collecting panel about 1½ years previously. I mounted my specimen for the Maritime Museum’s Dolphin display. Steve Reynolds of the Marine Life Society of South Australia picked the herbarium sheets and drawings up on 2/4/04. Bob and I went to Angas Inlet, and the North Arm/Port River site on 5/4/04 for more specimens of C. racemosa for the State Herbarium. We found plenty in Angas Inlet from the Postal Institute’s boat ramp, to the end of the Fishermen’s jetty (east of the public boatramp).
I have found Bugula neritina growing on an old Caulerpa racemosa ramulus, and three young colonies of an encrusting bryozoan (probably Celleporaria cristata; see Gordon D. P. 1989 p33 and plate 16, D-F) on a Caulerpa racemosa stolon. An older colony of what was probably the same encrusting bryozoan, was found on sea lettuce (Ulva sp.). Shepherd and Thomas (1982) Plate 28,4 is of a mature live colony.
So, like the European feather-duster worm, Caulerpa racemosa provides a stable substrate for other marine benthic organisms in a zone otherwise denuded of marine macrophytes (perhaps because of high nitrogen levels; see Neverauskas 1988; and presentations at the Friends of Gulf St Vincent forum held at SARDI Hamra Road on 22/10/05).
Close examination of a specimen of Caulerpa taxifolia from Angas Inlet (8/8/05) revealed the presence of many different phyla of marine invertebrates. Terebellids and other segmented worms, Amphipods, a brittle star, a seasquirt on a stolon, numerous silt tubes probably inhabited by crustaceans (Amphipods) and Isopods. The angle between main fronds and branches provided a microhabitat for many of the silt tubes. Rhizoids looked as if they would also provide a microhabitat for invertebrates (and many microorganisms). A knee-deep crop of C. taxifolia is likely to be far more productive than a “bare” area on which marine flowering plants have been killed off by other factors in a polluted environment. I say “bare” because I am well aware that there are microscopic photosynthetic and chemosynthetic organisms that can fix a lot of energy in these areas. I cannot comment on whether C. taxifolia can invade a healthy area of marine flowering plants not debilitated by polluting factors. We might be lucky to have C. taxifolia, just as many of our Arid Zone graziers feel lucky to have weeds like Barley Grass, Salvation Jane and Wards Weed (Carrichtera annua) stabilizing soils long-since denuded of native species by overgrazing. It is time to look at positive aspects of C. taxifolia.
C. racemosa recently found in the Port River and Angas Inlet
Brock B. J. (1979) Biology of Bryozoa Involved in Fouling at Outer Harbour and Angas Inlet. Unpublished M.Sc. Thesis University of Adelaide Zoology Dept.
Brock B. J. (1985) South Australian fouling Bryozoans. In Nielsen C. and Larwood G. P. (Eds.) Bryozoa: Ordovicion to Recent. (Olsen & Olsen) p.p. 45-49.
Gordon D. P. (1989) The Marine Fauna of New Zealand: Bryozoa: Gymnolaemata (Cheilostomata Ascophorina) from the Western South Island Continental Shelf and Slope. New Zealand Oceanographic Institute Memoir 95 plate 16, D.E.F., Celleporaria cristata.
Lucas A. H. S. (1936) The Seaweeds of South Australia. Govt. Printer Adelaide.
Neverauskas V. P. (1988) Accumulation of periphyton on artificial substrata near sewage sludge outfalls at Glenelg and Port Adelaide, South Australia. Trans. R. Soc. S.Aust. 112 (4) p.p. 175-177.
Shepherd S. A. and Thomas I. M. (1982) Marine Invertebrates of Southern Australia Part 1 Plates 15,3 and 15,4 for Cassiopea ndrosia, and 28,4 for mature live Celleporaria cristata.
Shepherd S. A. and Womersley H. B. S. (1970) The sublittoral ecology of West Island, South Australia 1. Environmental Features and the Algal Ecology. Trans. R. Soc. S. Aust. 94 p.p. 105-138.
Shepherd S. A. and Womersley H. B. S. (1971) Pearson Island Expedition 1969.-7. The Subtidal Ecology of Benthic Algae. Trans. R. Soc. S. Aust. 95 (3) p.p.155-167.
The other parts were: 1. Narrative 2. Geomorphology 3. Contributions to the Land Flora 4. The Pearson Island Wallaby 5. Reptiles 6. Birds 7. Helminths
Shepherd S. A. and Womersley H. B. S. (1976) The subtidal algal and seagrass ecology of St Francis Island, South Australia. Trans. R. Soc. S. Aust. 100 (4) p.p.177-191.
Thomas I. M. et al (1986) The effects of cooling water discharge on the intertidal fauna in the Port River estuary, South Australia. Trans. R. Soc. S. Aust. 110 (4) p.p. 159-172.
Womersley H. B. S. (1984) The Marine Benthic Flora of Southern Australia. Part 1. (Govt. Printer, Adelaide). Caulerpa spp., p.p. 253-274.
TROY M. JANTZEN* AND JON N. HAVENHAND#
School of Biological Sciences, Flinders University,
GPO Box 2100, Adelaide, South Australia, 5001
* To whom correspondence should be addressed. E-mail: Troy.Jantzen@ bms.com
# Current address: Tjämö Marine Biological Laboratory, Göteborg University, 452 96 Strömstad, Sweden.
Received 15 February 2002; accepted 31 January 2003.
Reference: Biol. Bul. 204:290 - 304 (June 2003)
C 2003 Marine Biological Laboratory
Sepioteuthis australis is a moderately large (≈30 cm mantle length) teuthoid squid, common throughout the coastal waters of southern Australia and New Zealand (Mangold and Clarke, 1998). Although prevalent throughout this region, no observations of copulation have been reported for this species, and spawning behavior has been reported only once in situ [as S. bilineata (Larcombe and Russell, 1971, see Mangold and Clarke, 1998)].
The object of the present note is to contribute to the knowledge of mating and spawning behavior of S. australis. The observations described here are the result of preliminary observations at the latter stages of the spawning period of this little-studied species. We provide a brief overview of S. australis mating and spawning behavior in the field, together with an insight into the proposed research that will be conducted on this species in future spawning seasons.
Materials and Methods
Throughout summer, S. australis move inshore to spawn, frequently utilizing the same spawning grounds each year (unpubl. observ.). Observations of S. australis reported here were obtained from a spawning ground approximately 20-40 m offshore (from the low tide mark) from the suburb of Marino, South Australia (130°30'E, 38°02'S). The benthos in this area consists of seagrass (Amphibolis antarctica) and brown macroalgae (Sargassum spp.) interspersed with patches of bare sand and rock, and extends for several kilometers along the coastline in this manner. The site at Marino is one of several spawning sites for S. australis along this stretch of coastline, all of which share these benthic characteristics.
During the spawning season, S. australis lay eggs in clusters consisting of numerous egg capsules (approximately 300 capsules per cluster; Larcombe and Russell, 1971), with each capsule containing 3-6 eggs. These egg clusters are commonly found attached to the thalli of the brown macroalgae Sargassum spp. This genus of macroalgae is also used as an egg deposition site for other squid species such as S. lessoniana (Segawa, 1987).
A total of nearly 4 h of ad libitum sampling (Martin and Bateson, 1993) were made over a 3 d period by SCUBA and snorkeling. Water depth on the spawning ground varied between 2-4 m depending on the tide. Squid behavior throughout the observation period was photographed with a Nikonos V camera. Attempts to record mating and spawning behavior using a Canon E850-Hi video camera in waterproof housing were unsuccessful due to an error with the tracking system on the camera. As a result, valuable ‘one-zero’ sampling (Martin and Bateson, 1993) data of mating and spawning could be analyzed. Furthermore, body patterning of the adults with each behavior could not be classified.
Results and Discussion
Egg Laying and Agonistic Behavior.—Larcombe and Russell (1971) documented the behavior of six adult S. australis (two male, four female) as the females attached egg capsules to an egg cluster that had detached from its normal habitat and had become entangled in an artificial reef. In contrast, the observations reported here describe spawning by numerous individuals on egg clusters attached to Sargassum spp.
Sex ratio on the spawning ground was male biased. Although quantitative measurements of the specific number of males and females in view at any one time were not obtainable from the video footage, direct observation showed that all females were paired with a male while several unpaired males swam amongst the paired individuals. These unpaired males were observed attempting to displace paired males from their mate: a behavior that was met with fierce agonistic responses from the paired male who would endeavor to remain between the female and the competitor using his mantle and fins. Agonistic behavior often escalated into a fight with both males extending their arms and tentacles and colliding into each other (Fig. 1). If the unpaired male did not withdraw, a swimming fight would result, and the two males rapidly swam out of visible range while continually colliding in this manner. ‘Swimming fights’ left the female unattended and subject to pairing with other competitive males. Although this behavior appears detrimental to the paired male, it may be advantageous to the female, and a similar behavior has been observed in the cuttlefish Sepia apama where females engage in extra pair copulations while a guarding male is preoccupied with fighting with a competitor (R. T. Hanlon pers. comm., 2000).
Figure 1. Two males fighting. The paired male (bottom) is using his body
and fins to ‘guard’ his mate (background) from the advances of an
unpaired male (top).
In one instance, rather than a ‘swimming fight’, agonistic behavior escalated to physical combat (DiMarco and Hanlon, 1997) and a paired male was seen wrapping his tentacles and arms completely around the mid-mantle region of an unpaired male. This behavior has also previously been observed in fights among S. apama and is assumed to be an attempt to bite the intruder (R. T. Hanlon pers. comm., 2000). Like the response of the unpaired males in the S. apama fights, the unpaired S. australis male immediately jetted away.
As well as defending their female from other males by fighting, paired males guarded the female while she laid eggs. ‘Mate-guarding’ (sensu Sauer et al., 1992; Hanlon and Messenger, 1996) involved the male remaining a few centimeters above his mate while she attached egg capsules to a cluster (Fig. 2). Immediately following egg-laying, the pair moved backwards away from the egg cluster and began a ‘mutual-rocking’ behavior (Moynihan and Rodaniche, 1982; Hanlon and Messenger, 1996) in which the pair swam side-by-side in a slow and deliberate forward and back motion. This behavior stopped when the female approached the egg cluster and deposited a new capsule amongst it in the same manner as that described by Larcombe and Russell (1971).
Figure 2. Male (top) guarding a female (below) as she prepares to add
a new egg capsule to a cluster (not visible in photo). Broken
spermatophores from a previous mating attempt (successful mating
results in spermatophores being deposited in the buccal region of the
receptive female) can be seen on the dorsal surface of the female.
Egg laying behavior of squid in spawning aggregations has been observed in numerous species congregating around a large, central, relatively exposed, communal egg cluster (Griswold and Prezioso, 1981; Sauer et al., 1992; Segawa et al., 1993; Hanlon et al, 1994; 1997; Hanlon and Messenger, 1996). In our observations of S. australis spawning, no more than three paired females were seen laying eggs in the same egg cluster. Furthermore, although common in some squid species (Hanlon and Messenger, 1996), no distinctive ‘zones’ of mating and spawning activity could be identified for S. australis throughout the observational period. It is possible that further observation will clarify this issue.
Copulation Behavior of Paired Males.—Copulation in Sepioteuthis involves the male depositing spermatophores into either the mantle cavity when the male approaches from below the receptive female (Segawa, 1987; Segawa et al., 1993), or onto the arm region when the male approaches from beside or above the female (Moynihan and Rodaniche, 1982; Boal and Gonzalez, 1998). When spermatophores are placed on the female arm region, the male does so in one of two ways: in reports of S. sepioidea mating in the field, the male positions himself next to, or ahead of the female, turns towards her, and ‘strikes’ the female on the ‘forehead’. Alternatively, reports of S. lessoniana mating in the laboratory describe a mating position in which the male ‘flips’ upside-down to deposit spermatophores on the head or arms of the female (Boal and Gonzalez, 1998). It is this latter ‘male-upturned’ mating position that was observed by paired males of S. australis in the field.
Mating with the male in the upturned position was observed on six occasions, each of which occurred prior to egg laying by the female while the spawning pair was in close proximity to the egg cluster (usually <1.5 m). Boal and Gonzalez (1998) categorized the male-upturned mating behavior of S. lessoniana into four distinct behaviors, of which only three were observed here: ‘pre-mating behavior’, ‘flip’, and ‘contact’; the fourth (‘attempt’) not being observed in S. australis.
S. australis still displayed some behavioral traits consistent with S. sepioidea mating in the field (Moynihan and Rodaniche, 1982). Unlike ‘pre-mating’ behavior in S. lessoniana that involved rapid back and forth swimming by the mating pair (Boal and Gonzalez, 1998), ‘mutual-rocking’ in S. australis was slow and deliberate, similar to that described for S. sepioidea (Moynihan and Rodaniche, 1982). Immediately prior to mating, male S. australis were observed to fold back one tentacle horizontally toward the female for a few seconds, such that the suckers on the club of the male faced toward the female, a behavior that may be unique to S. australis mating. The purpose of this ‘club display’ behavior remains unclear, however it may signal the male's intention to mate with the female.
Following the male ‘club display’ to the female, the male was observed to move directly above, or slightly anterior to, the body of the female. The male then swiftly rotated 180° around the longitudinal axis to achieve an inverted position above the female. This ‘flip’ action was observed in males positioned both alongside as well as above the female in S. lessoniana (Boal and Gonzalez, 1998). However, in S. australis it occurred when the male was above the female.
While inverted, the male reached down with an arm and made cont with the buccal area of the female (Fig. 3). From our observations we were unable to determine if mating in this manner was successful. Unlike S. lessoniana in which mating ended with the female rapidly jetting away (Boal and Gonzalez, 1998), ‘contact’ in S. australis was terminated when the male returned to his original position alongside the female, similar to the post-mating behavior described for S. sepioidea (Moynihan and Rodaniche, 1982). In S. sepioidea spermatophores are visible on the hectocotlyus of the male prior to mating (Arnold, 1965). This was not the case for the mating behavior described here and the only spermatophores observed were those affixed to the dorsal mantle of a female (Fig. 2). It is assumed that a male placed these spermatophores there in an unsuccessful mating attempt, although the behavior that resulted in that placement was not observed.
Figure 3. Lateral view of the male upturned mating position. The male
(top) can be seen in an upside down position reaching down in an attempt
to deposit spermatophores in the buccal region of the female (below).
Extra-pair Copulations.—As well as ‘male-upturned’ mating by paired males, behavior consistent with extra-pair copulations in other species was observed by unpaired S. australis males. In Loligo pealei and L. vulgaris reynaudii, extra-pair copulations occur by ‘sneaker males’ mating with females both at the large communal egg mass, and at a short distance from the egg mass (the ‘mating/sneaker zone’; Hanlon, 1996; Hanlon and Messenger, 1996; Hanlon et al., in press). All of the extra-pair copulations that were observed in S. australis occurred as a female added a new egg capsule to an egg cluster.
While laying eggs, the depth of the algal canopy was such that only the mantle tip of the female protruded above the algae. Therefore, males guarding a mate were always positioned some distance above the substratum either immediately above or beside the female. Unpaired males were observed to swim rapidly toward the female from the side or behind, dart amongst the Sargassum and make physical contact with the female before quickly jetting away. The nature of this contact was similar to the ‘sneaker’ mating observed in L. pealei (Hanlon et al., 1994).
‘Sneaker’ mating by an unpaired male was identified once throughout the observational period, while at least two other encounters showed aspects of sneaking mating. In the first instance, an unpaired male made contact with the arms of a female which was visibly laying eggs in a cluster. This behavior occurred very rapidly such that it was not possible to determine if mating was successful, and (if so) where the spermatophores were deposited. On two further occasions a male was seen disappearing into the algal canopy within 0.5 m of a female laying eggs, soon afterward reappearing and quickly jetting away. In these cases the head of the female was almost completely obscured from view by the Sargassum and no copulation was seen. However, behavior of the unpaired male in these latter two instances was identical to that seen in the previously described encounter.
Figure 4. Unpaired male (left) attempting to displace another male (middle)
from his mate (right). The two males have tentacles and arms out-stretched
in a sign of agonistic behavior. In the bottom left comer, an empty egg
capsule is noticeable.
Empty Egg Capsules.—Egg capsules were attached to the top of the Sargassum in the spawning area on each day of observation (Fig. 4). Closer examination revealed that these egg capsules did not contain any eggs. Furthermore, these capsules were absent in the week following the spawning event (although numerous egg clusters remained present). The purpose of these empty capsules is not clear, however at least two possible functions can be speculated: (1) locational ‘markers’: given our observations of repeated egg laying on established egg clusters, the migration to and from these clusters during the ‘mutual-rocking’, and the dense algal canopy which frequently obscured egg clusters from view, these empty capsules may flag the position of egg clusters, facilitating their location by adults. (2) Capsules act as spawning stimulants: as egg capsules have been demonstrated to induce male agonistic behaviour in laboratory trials of L. pealeii (King et al., 1999), and promote spawning in L. pealii (Arnold, 1962) and Loligo opalescens (Hurley, 1977), egg capsules (empty or full) may stimulate spawning of adults entering the area. The reason for this may be visual or, as recent studies have suggested, may be a response to a chemical or tactile stimulus embedded in the egg capsules (King et al., 1999). Further studies are required to verify these hypotheses.
Observations of a natural spawning aggregation of approximately 40 S. australis in South Australia have revealed several previously undescribed aspects of spawning behavior in this species. Male S. australis repeatedly copulated in the ‘male-upturned’ position and engage in behavior similar to extra-pair copulations that are reported for other squid species. Further research is being conducted in an attempt to determine the precise nature of these behavioral traits. Focal animal sampling of fighting, mating and spawning behavior using a digital camera will enable specific body patterning of each sex to be analyzed. Continuous recording of the focal animal(s) will also identify duration of spawning and mating, time between these events, and the frequency and characteristics of extra-pair copulations. In addition, empty egg capsules, which may serve as locational markers and/or spawning stimulants, were observed deposited on the distal fronds of macroalgae within the spawning area Laboratory and field studies will investigate this unusual behavior.
We are thankful to L. van Camp for comments on this research, and to B. Lock, A. Mack, and A. Hirst for help SCUBA diving and snorkeling in the field.
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Boal, J. G. and S. A. Gonzalez. 1998. Social behaviour of individual oval squids (Cephalopoda, Teuthoidea, Loliginidae, Sepioteuthis lessoniana) within a captive school. Ethology 104: 161-178.
DiMarco, F. P. and R. T. Hanlon. 1997. Agonistic behavior in the squid Loligo plei (Loliginidae, Teuthoidea): Fighting tactics and the effects of size and resource value. Ethology 103: 89-108.
Griswold, C. A. and J. Prezioso. 1981. In situ observations on reproductive behaviour of the long-finned squid, Loligo pealei. Fish. Bull. U.S. 78: 945-947.
Hanlon, R.T., M. J. Smale and W. H. H. Sauer. (in press). The mating system of the squid Loligo vulgaris reynaudii (Cephalopoda, Mollusca) off South Africa: fighting, guarding, sneaking, mating and egg laying behavior. Bull. Mar. Sci.
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_______ and J. B. Messenger. 1996. Cephalopod behaviour. Cambridge Univ. Press. Cambridge.
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______, M. R. Maxwell and N. Shashar. 1997. Behavioral dynamics that would lead to multiple paternity within egg capsules of the squid Loligo pealei. Biol. Bull. 193: 212-214.
Hurley, A. C. 1977. Mating behavior of the squid Loligo opalescens. Mar. Behav. Physiol. 4: 195-203.
King, A. J., S. A. Adamo and R. T. Hanlon. 1999. Contact with squid egg capsules increases agonistic behavior in male squid (Loligo pealeii). Biol. Bull. 197: 256-258.
Larcombe, M. F. and B. C. Russell. 1971. Egg laying behaviour of the broad squid, Sepioteuthis bilineata. NZ J. Mar. Freshw. Res. 5:3-11.
Mangold, K. and M. R. Clarke. 1998. Subclass Coleoidea. Pages 499-563 in P. L. Beesley, G. J. B. Ross, and A. Wells, eds. Mollusca: The southern synthesis. Fauna of Australia. CSIRO Publishing, Melbourne.
Martin, P. and P. Bateson. 1993. Measuring Behaviour: An Introductory Guide. Cambridge Univ. Press, Cambridge.
Moynihan, M. and A. F. Rodaniche. 1982. The behavior and natural history of the Carribean reef squid Sepioteuthis sepioidea. With a consideration of social, signal, and defensive patterns for difficult and dangerous environments. Adv. Ethology 25: 1-151.
Sauer, W. H. H., M. J. Smale, and M. R. Lipinski. 1992. The location of spawning grounds, spawning and schooling behaviour of the squid Loligo vulgaris reynaudii (Cephalopoda: Myopsida) off the Eastern Cape Coast, South Africa. Mar. Biol. 114: 97-107.
Segawa, S. 1987. Life history of the oval squid, Sepioteuthis lessoniana in Kominato and adjacent waters central Honshu, Japan. J. Tokyo Fish. 74: 67-105.
_____, T. Izuka, T. Tamashiro, and T. Okutani. 1993. A note on mating and egg deposition by Sepioteuthis lessoniana in Ishigaki Island, Okinawa, Southwestern Japan. Venus (Jap. J. Malac.) 52:101-108.
addresses: (corresponding author): (T.M.J.) Marine Biology, School of Biological Sciences, Flinders University, GPO Box 2100, Adelaide, South Australia, 5001. Tel. +618 8201 5184. Fax + 61 8 8201 3015. E-mail: <Troy.Jantzen@flinders.edu.au>. (1,N.H.) Deputy Head, School of Biological Sciences, Flinders University, GPOBox2100, Adelaide, South Australia, 5001. Tel. +618 8201 2007. Fax+ 61 8 8201 3015. E-mail: <Jon.Havenhand@flinders.edu.au>.
by Steve Reynolds
Since the publication of my article “Numerous Nudibranch Findings” in our June 2005 Newsletter (No.322), SA diver Dennis Hutson continues to make more nudibranch discoveries.
“Numerous Nudibranch Findings” reported findings of Polycera hedgpethi, Elysia Sp. (E.?expansa), Flabellina Spp. (3) and Aegires villosus by Dennis.
Each of these species features in “1001 Nudibranchs” by Neville Coleman. Polycera hedgpethi, however, is incorrectly spelled as Polycera hedgepethi in that book. (I, myself, spelled ‘opisthobranch’ incorrectly in my article.)
Our Society purchased “1001 Nudibranchs” since my article was written. It is primarily used for identification and classification work for our Photo Index but it is available from our library for limited loan to Society members (mlssa No.1050).
“1001 Nudibranchs” does not include SA in the distribution details given for Polycera hedgpethi, Elysia Sp. (E.?expansa)*, Flabellina Spp. (3) and Aegires villosus. This means that Dennis’s information is quite important.
*It may not have been made entirely clear in my article “Numerous Nudibranch Findings”, but Elysia species
Elysia Sp. are not nudibranchs at all. They are, in fact, sap sucking slugs (Order Sacoglossa).
“The Sea Slug Forum – Species List” gives the following details for Elysia species: -
Order Sacoglossa, Superfamily Elysioidea, Family Elysiidae.
On 8th June 2005 Dennis sent an email message to Nerida Wilson (formerly of the SA Museum) to let her know that specimens of Polycera hedgpethi had returned to the North Haven boat ramp. Nerida is now working at the Department of Biological Sciences at Auburn University in Alabama, USA. Dennis had been looking out for Polycera hedgpethi every week and discovered them again whilst collecting water for his aquarium. He told Nerida that the size of the animals was small, about 10mm. “If you know their growth rate you should be able to work out when they actually returned. They’re the first I’ve seen this year. The water temperature has now dropped to 16 degrees C.”
I later asked Nerida if she had received Dennis Hutson's message about the late reappearance of Polycera hedgpethi. She replied that she had and that she had managed to incorporate it into her paper before it went to the printers.
“Just in time!” she said. “It’s a very interesting observation. The name honours Joel Hedgpethi, a marine scientist that worked mostly in California, I think...here you go, a quick web search found this...
“Joel Walker Hedgpeth, 1911-, Californian pycnogonid taxonomist and ecologist, active between the 1930s-1980s [Hedgpethia turpaeva, 1973, Coboldus hedgpethi (J.L. Barnard 1969), Laophontodes hedgpethi Lang, 1965, Chaetozone hedgpethi Blake, 1996, Polycera hedgpethi Marcus, 1964, Ammothea hedgpethi, Elysia hedgpethi ].”
“The Sea Slug Forum – Species List” gives the following details for Polycera hedgpethi :-
Order Nudibranchia, Suborder Doridina, Family Polyceridae, Subfamily Polycerinae.
On 12th February 2005 Dennis found a tiny 5 mm long nudibranch in Gulf St Vincent on Seacliff Beach. As usual, Dennis took a photo of the tiny critter and sent it in to the Sea Slug Forum at http://www.seaslugforum.net asking for it to be identified.
The Sea Slug Forum is operated by Dr Bill Rudman, Curator of Molluscs at the Australian Museum.
In his response to Dennis, Dr Bill Rudman said: -
This is interesting on two counts. Firstly, I think it is a juvenile of Noumea haliclona. This is interesting because, although it is known from New South Wales, Victoria and Tasmania, this is the first record I know of it from South Australia. As you will see from the Fact Sheet, its colour matches one of the colour forms found in Tasmania. The second interesting point is that its rhinophores are fused. Instead of being a pair, there is one large central rhinophore apparently in a single large pocket. This is obviously a result of some fault during its larval development. If you are interested, have a look at the fact sheet where I have listed other developmental abnormalities”.
The fact sheet included these details: - “This small chromodorid is common in south eastern Australia both intertidally and sublittorally from northern New South Wales, to Victoria and Tasmania. It is one of the red-spotted colour group of chromodorids from this region and exhibits both colour variation within a region [sympatric variation] & distinctive regional colour forms [allopatric variation], which are illustrated on this page. There are no distinguishing anatomical features between the regional colour morphs. Externally, small scattered red or orange spots, and a red or orange mark on the front of the rhinophore club are the two characters which link these forms together. They feed on a range of pink and yellow aplysillid sponges.
According to the fact sheet, Noumea haliclona (Order Nudibranchia) is of the Suborder Doridina, Superfamily Eudoridoidea and Family Chromodorididae.
The fact sheet can be seen at: -
http://www.seaslugforum.net/factsheet.cfm?base=noumhali1 . Noumea haliclona features on page 83 of “1001 Nudibranchs”.
On 18th June 2005 Dennis was diving solo at Outer Harbor when he discovered another tiny (12mm) nudibranch on some Caulerpa (racemosa?). Dennis took this photograph of the colourful little nudibranch and later sent it to me for identification.
I was able to identify it from Neville Coleman’s book “Nudibranchs of the South Pacific” as being Thecacera pennigera. I still suggested to Dennis that he send his photo in to the Sea Slug Forum. He did that on the 20th June, with the following message: -
“Can you please confirm this is Thecacera pennigera?
Locality: Outer Harbor, Adelaide, South Australia. Depth: 3 metres. Length: 12 mm. 18 June 2005. silty. Photographer: Dennis Hutson.
Is it native to Adelaide, South Australia?
Cheers, Dennis Hutson”
Dennis soon received the following reply from Dr Bill Rudman: -
Yes this is Thecacera pennigera. Your question about where it comes from is quite interesting. It was originally described from England so we have assumed that it is a North Atlantic species. However it has since been found in many parts of the world as you will see from the Fact Sheet and accompanying messages. It feeds on bryozoans which are part of the 'fouling community', a name for plants and animals which grow on hard surfaces, and in particular, the bottom of boats. We have assumed that this species has spread from the North Atlantic on the bottom of boats. However most species of Thecacera are found in the Indo-West Pacific region, and as you will see from looking at the photos on the Forum, there is much more colour variation in animals from the Pacific than from the North Atlantic. This could suggest that the Pacific is the original home of this species and what we now find in the North Atlantic is a population based on a few Pacific animals with small spots that were transported there on the bottom of sailing ships two centuries ago.
I guess this could be tested by DNA analysis.
(These details can be found at http://www.seaslugforum.net/display.cfm?id=14077 .)
The fact sheet accompanying Bill’s reply indicated that Thecacera pennigera (Order Nudibranchia) belongs to the Suborder Doridina, Family Polyceridae and Subfamily Polycerinae*. It said that the species had been originally reported from the Atlantic coast of Europe, but it is now known from South Africa, West Africa, Pakistan, Japan, Brazil, eastern Australia and New Zealand.
The fact sheet can be seen at :-
*This makes Thecacera pennigera a close relative of Polycera hedgpethi which shares the same details.
“1001 Nudibranchs” features both Thecacera pennigera and Noumea haliclona, but the book does not include SA in the distribution details given for either. Once more, this means that Dennis’s information is quite important.
Thecacera pennigera is featured on page 47 of “1001 Nudibranchs” and page 14 of “Nudibranchs of the South Pacific”.
Again, as with Polycera hedgpethi, CRIMP’s “A Guide to the Introduced Marine Species in Australian Waters” by Dianne M Furlani has a page of details about Thecacera pennigera under “Mollusca” (updated May 1996). (CRIMP is the acronym for Centre for Research on Introduced Marine Pests.) Also as with Polycera hedgpethi, this page also features a Richard Willan and Neville Coleman 1984 photo of the nudibranch. This appears to be one of the same photos (AMPI 73) featured in “1001 Nudibranchs” and the same one featured in “Nudibranchs of the South Pacific Vol.1” by Neville Coleman.
(AMPI is the Australasian Marine Photographic Index which is curated by Neville Coleman. According to Neville, the Index is “a comprehensive scientifically curated visual identification system containing over 150,000 individual transparencies covering almost every aspect of aquatic natural history”. The colour transparencies of living animals and plants in the Index are “cross-referenced against identified specimens housed in museums and scientific institutions”.)
“A Guide to the Introduced Marine Species in Australian Waters” says that, although Thecacera pennigera is a Polycerid, it “differs consistently from Polycera in (both) absence of velar process and presence of rhinophore sheath”. Also, “body tapers to long foot, 2 lateral extensions posteriorly, and no velar process”.
According to the glossary in both “1001 Nudibranchs” and “Nudibranchs of the South Pacific Vol.1”, a ‘rhinophore (rhinophoral) sheath’ is an “upstanding flange from the antero-lateral part of the mantle (of dendronotacean nudibranchs) into which the rhinophore can be contracted”. The glossary says that a ‘rhinophore’ is “sensory tentacle on the head or anterior section of the mantle of opisthobranchs”.
I also wanted to know what ‘velar’ was. I couldn’t find the word in any of the glossaries that I checked out. It was, however, shown in a diagram of a dorid nudibranch in “1001 Nudibranchs”. There also seemed to be a connection between ‘velar’ and ‘velum’. It so happened that I had the opportunity to ask Greg Rouse at the SA Museum about this matter.
“Do you know much about nudibranchs?” I asked him. “Can you explain what velar/velum are?”. Greg suggested that his partner, in the USA (who happens to be Nerida Wilson) would be the best person to help me. He said that he had passed my query on to her.
Nerida soon replied to my query, saying that “The velum is the part of a nudibranch larva that is covered with cilia that help it swim/feed. It has two (velar) lobes. There is a nice picture of a larvae where you can clearly see the foot, and the velar lobes poking out from the shell on the sea slug forum at :-
I think during metamorphosis that the velar lobes are reabsorbed into what becomes the mantle. Hope it helps. Nerida”
I checked out http://www.seaslugforum.net/factsheet.cfm?base=larvshel where I found the following picture by Yoshi Hirano: -
Yoshi Hirano's picture clearly
showing the transparent larval
shell of the aeolid nudibranch
This would seem to be the picture referred to by Nerida “of a larvae where you can clearly see the foot, and the velar lobes poking out from the shell”.
Incidentally, Neville Coleman gives most nudibranch species a common name. For example, he calls Thecacera pennigera “Winged Thecacera.” Noumea haliclona is called “Sponge Noumea” and Aegires villosus is called “Shaggy Aegires.” Polycera hedgpethi is called “Hedgepeth’s Polycera” (should be “Hedgpeth’s Polycera”). The opisthobranch Elysia expansa is called “Wide Elysia.”
Dennis is keeping his specimen of Elysia Sp. (E.?expansa) in his home aquarium. The opisthobranch is doing very well in the tank and it has laid eggs on a couple of occasions.
On 13th August 2005 Dennis photographed a small specimen of the Sweet Ceratosoma, Ceratosoma amoena at the Glenelg Tyre Reef.
There has been some confusion over the correct scientific name for the Sweet Ceratosoma. I have come across the name Ceratosoma amoenum in place of Ceratosoma amoena. Nerida Wilson says that Ceratosoma amoena is the correct name. She explains, however, that the species used to be placed in the genus Chromodoris (as Chromodoris amoenum). It was later moved into the genus Ceratosoma and the species name was then changed to match the gender of the new genus (Ceratosoma amoena).
Later on, Nerida explained the above details to me once more by saying, “The animal was first called (Chromodoris) amoenum, but when it was put in to the genus Ceratosoma instead, the specific name was changed to amoena to be in agreement with the gender of the genus name Ceratosoma”.
It seems then that different genus are considered as different gender. Nerida told me “It’s confusing to know which genus name is feminine or masculine, etc, and when a change is needed. However, while it is strictly correct to change the species name to match (the gender of the genus name), not all people stick to this. But for your species, amoena is the correct and common usage nowadays” she said.
On 10th July 2005 Dennis sent me two more photos of nudibranchs that he had found on the Glenelg Barge the day before. He also sent both of the photos on to Nerida Wilson, Thierry Laperousaz, Senior Collection Manager for Marine Invertebrates at the SA Museum’s Science Centre and the Sea Slug Forum. Dennis and I had several discussions about the identification of the two nudibranchs but Nerida was the first person to respond with an ID.
“I think it is Noumea sulphurea” she said, “although there is a possibility it is N.closei. You may be able to see better whether there are any small orange specks on the back, which will likely indicate N.closei”.
Dennis also thought that it might be Noumea sulphurea. He directed me to http://www.seaslugforum.net/factsheet.cfm?base=noumsulp2 .
The web page features two photos of Noumea sulphurea. They were both said to be the “Bass Strait colour form” (both from Tasmania in 1985). The distribution for Noumea sulphurea was given as being “Southern Australia - Tasmania, Victoria & South Australia”.
The web page went on to say that “Specimens from Tasmania, Victoria and South Australia differ from New South Wales animals in having regularly spaced white specks all over the dorsum except for a clear band near the edge, the specks apparently being formed from aggregations of subepithelial granules. In some specimens there is also an aggregation of these granules right at the edge of the mantle to form a broken white line along the edge. The colour of the orange spots is also much less brilliantly opaque than New South Wales animals, the spots often being almost invisble in smaller specimens.
This ‘Bass Strait colour form’ is very similar in colour to Noumea closei and the yellow Tasmanian colour form of Noumea haliclona”.
Dennis’s enquiry was posted to the Sea Slug Forum site on 20th July 2005 at http://www.seaslugforum.net/display.cfm?id=14265. Bill Rudman said that it was, in fact, Noumea closei. The web page read: -
“Noumea closei from South Australia (From: Dennis Hutson)”
Could this please be identified and is it native to South Australian waters?
Locality: wreck of the Barge, Glenelg, South Australia. Depth: 16 m. Length: 10 mm. 9 July 2005, Deck of the wreck, Photographer: Dennis Hutson”.
Bill Rudman responded with: -
This is Noumea closei, which is known from Victoria, Tasmania and South Australia. Have a look at the Fact Sheet for more information on it and the other similarly coloured species.
The facts sheets for Noumea closei and Noumea sulphurea are http://www.seaslugforum.net/noumclos.htm
Dennis told me that he thought that it was N.sulphurea because of this other link - http://www.seaslugforum.net/display.cfm?id=6309 . “Bill mentions the white marks on top” said Dennis. The web page read: -
“Noumea closei from South Australia
March 10, 2002
From: Stuart Hutchison
Here’s one were not sure about from the wreck of The South Australian, Adelaide, South Australia on 26 Sep 1999. Depth 20m, length 15mm.
I am pretty sure, from the white marks, that this is Noumea closei. However if you look at the Bass Strait colour form of Noumea sulphurea you will see it is almost identical externally. There is an interesting story attached to how I first realised there were two species involved. N. closei when preserved in formalin turns dark brown, sometimes almost black, while Noumea sulphurea gradually loses all its colour, becoming translucent white. One day, when I was choosing some specimens to dissect, I decided I had better check some dark and some light coloured ones just in case I had missed something. To my great surprise I found their radular morphology was quite different.
preserved colour of a slug is not the most practical way to identify a species,
but as with species of Rostanga, sometimes
external shape and colour just isn't enough.
Noumea sulphurea is featured on page 84 of “1001 Nudibranchs” and page 42 of “Nudibranchs of the South Pacific”. Neville calls it a Sulphur Noumea. Noumea closei is not in either book.
We still don’t know, at the time of writing, what species Dennis’s second photograph is. Neither Nerida Wilson, Bill Rudman or Neville Coleman have been able to identify it.
An aeolid nudibranch on the Barge at Glenelg
After viewing MLSSA’s copy of “1001 Nudibranchs”, Dennis ordered a copy for himself to assist with identifications. He found that one of Nerida Wilson’s nudibranch photos is featured on page 89. It is a Doriopsis pectin (Blue Doriopsis).
Dennis photographed specimens of Discodoris concinna and a Dendrodoris whilst diving at Outer Harbor. He reported the discoveries to Thierry Laperousaz at the SA Museum.
Thierry advised Dennis that he thought that Discodoris concinna was rare in SA. Dennis has since collected a specimen for the museum.
An aeolid nudibranch on the Barge at Glenelg
Discodoris concinna is featured on page 23 of “Nudibranchs of the South Pacific”. Thierry thought that the Dendrodoris that Dennis had photographed was Dendrodoris nigra. Dennis feels that it is actually Dendrodoris fumata as it is more commonly found in our waters. He says that there is a subtle difference in the gill structure but they are very difficult to tell apart.
Stuart Hutchinson thought that he had taken some photos of Dendrodoris nigra at Edithburgh jetty in January 1999. He sent two photos to the Sea Slug Forum in February 2000. Bill Rudman responded as follows: -
This is Dendrodoris fumata, not Dendrodoris nigra. Have a look at my comments on each page to see the differences ( http://www.sealugforum.net/dendfuma.htm and http://www.seaslugforum.net/dendnigr.htm ).
These two species have been confusing us for over a century as both have the same range of colour forms. One good difference seems to be the shape and number of gills. In D. fumata there are a few (usually 5) large gills, which are usually extended out to the mantle edge. In D. nigra there are many small gills arranged in a cup-shaped circle. In both your photos I think I can see parts of the bright yellow egg ribbon. It also appears that the sponge they are on is a food source.
These details, with the two photos, are available at :-
Dendrodoris fumata is featured on page 86 of “1001 Nudibranchs” and Dendrodoris nigra is featured on page 87. Neville Coleman calls Dendrodoris fumata Hazy Dendrodoris and Dendrodoris nigra Black Dendrodoris. “1001 Nudibranchs” says that both belong to the Dendrodorididae family.
photographed a Hypselodoris species of nudibranch
whilst diving at the Blocks at Glenelg on 21st November 2004. Someone suggested
that it was Hypselodoris infucata but Dennis thought that it might be Hypselodoris saintvincentius
as this species is more commonly found in our waters. As he understands it,
the difference is in the colouring. On 26th
August 2005 Dennis posted the following details on to the Sea Slug Forum: -
“Could you please confirm the id of this critter? The photo was taken at a site known as the Glenelg Blocks, which is located approx. 500m off the beach of Glenelg, South Australia, Gulf St. Vincent. I was told it was Hypselodoris infucata but I thought it might be Hypselodoris saintvincentius. I understand there is a slight difference in colour. Thanks for your help.
Locality: Glenelg Blocks off Glenelg Beach, South Australia, Southern Ocean. Depth: 5 m. Length: 40 mm. 21 November 2004. Rocky bottom Photographer: Dennis Hutson”
Bill’s reply was as follows: -
Your animal is Hypselodoris saintvincentius. As I discuss in a recent message [http://www.seaslugforum.net/find.cfm?id=14285], it is not that easy to separate from H. infucata.
Hypselodoris infucata is featured on page 80 of “1001 Nudibranchs”. Neville Coleman calls it Painted Hypselodoris. “1001 Nudibranchs” says that, like Noumea closei, Noumea sulphurea and Ceratosoma amoena, Hypselodoris infucata belongs to the Chromodorididae family.
In August 2005 Nerida asked Dennis and I to arrange for the collection of Polycera hedgpethi sspecimens for her. She said that she was trying to set up a project that uses the DNA sequences of all P.hedgpethi populations worldwide, to try and determine which populations are connected by gene flow, etc.. “I am hoping to be able to determine where the natural range of Polycera was in the world, and if it is truly introduced or not. This requires many more specimens than Dennis collected for me last year. Is there any chance that you might be able to help, or know someone who may? I basically need about 25 specimens, and someone to take them into the museum where Greg or Thierry can fix them for me” she said.
That same month (August 2005) Dennis and I dived at Outer Harbor in low visibility. We couldn’t find any Polycera hedgpethi but Dennis managed to find another Elysia species. He also photographed and collected another unusual nudibranch.
After the dive Dennis studied the photograph and “1001 Nudibranchs”. He suggested in an email message to me that it may possibly be a Discodoris lilacina (p.56) or Dendrodoris albobrunnea (p.86). Whilst “leaning towards the first” he decided to post it onto the Sea Slug Forum for confirmation.
On Sunday 28th August I snorkeled at Dock 1 in the Port River to search for specimens of Polycera hedgpethi for Nerida. I didn’t have any luck at all and advised Nerida and Dennis. Dennis reported that he had collected 4 specimens for her from the North Haven boat ramp. This gave Dennis the opportunity to take some more photos of the species. He said that he was taking them in to the SA Museum alive for Thierry to fix for Nerida.
Dennis has set up his own web site which features different galleries of his photos, both above and below water. The address for the site is :-
Many of Dennis’s nudibranch photos are being posted to the site.
Many thanks to Dennis Hutson, Nerida Wilson, Thierry Laperouzas and Bill Rudman for their considerable assistance with the above details.
“Nudibranchs of the South Pacific Vol.1” by Neville Coleman, Sea Australia Resource Centre, 1989, ISBN 0 947 325 02 6.
“1001 Nudibranchs” by Neville Coleman, Underwater Geographic P/L, 2001, ISBN 0947325255 – mlssa No.1050.
“Numerous Nudibranch Findings” by Steve Reynolds, MLSSA Newsletter June 2005 (No.322).
Australasian Nudibranch News 2:4 (Volume 2 (4): 3, December 1999)
The Sea Slug Forum – Species List
1. Dennis Hutson of Elysia species
2. Dennis Hutson of Polycera hedgpethi
3. Dennis Hutson of Noumea haliclona
4. Dennis Hutson of Thecacera pennigera
5. Yoshi Hirano of the transparent larval shell of the aeolid nudibranch Facelina bilineata.
7. Dennis Hutson of Noumea closei
8. Dennis Hutson of an aeolid nudibranch found on the Barge at Glenelg
9. Dennis Hutson of Discodoris concinna
10. Dennis Hutson of the Dendrodoris (?nigra)
11. Dennis Hutson of Hypselodoris saintvincentius
12. Dennis Hutson of an unusual nudibranch found at Outer Harbor
by Steve Reynolds
Our Society occasionally receives requests (usually by email) for information on marine topics. A few such requests, and subsequent replies, have been put together below: -
Late in 2003 we received the following request for information:-
“Hi… I’m a Bachelor of Science student (Biology major) looking for some information on the Leafy Seadragon for an ecology assignment. It’s only for my 2nd year Ecology essay, but it’ll be invaluable. As my studies continue, I plan to focus on the marine ecology of the Hallett Cove/Marino area where I live – a very interesting and unique little bit of coastline. I’m actually a plant science fanatic, so my special interest is actually the local seaweed!
I was able to provide Anissa with the references that she requested for her assignment. I asked her to keep in touch and let us know how she gets on with it.
The following message then came from Heather Wadley in January 2005.
“Subject: I am in search of information on the Leafy Sea Dragon.
Dear MLSSA members,
My name is Heather Wadley, I am a 12th grade student at a Massachusetts school in the United States. I am taking an oceanography class, and my teacher, Mrs. Streck is having us do a project on a oceanic creature. I have looked online for the internal and external structure of the Leafy Sea Dragon. I stumbled across your newsletter when doing a search online, and saw that you offered the information about the anatomy of a Leafy Sea Dragon, and I was wondering if it might be possible for you to share the information, if you have pictures that are possibly labeled, or not labeled. I greatly appreciate your help if you can help me or not with the pictures. Again, thank you very much for your assistance.
We sent the following reply to Heather: -
Firstly, I have attached two pictures from our Photo Index. You will find lots of articles about the Leafy in our September 2004 newsletter on our web site. You will find some more photos there. I have also attached a seadragon reference list that I have compiled.
Here are some details about Dragon Search’s Code of Conduct.
‘DIVING WITH DRAGONS - CODE OF CONDUCT’
The ‘Diving with Dragons - Code of Conduct’ sets out a few simple guidelines that divers can follow to reduce their impact on seadragons. The “Diving with Dragons - Code of Conduct” asks divers to: -
where they are;
Look but don't touch;
Respect their home range and avoid herding;
Avoid moving seadragons up or down in the water column;
Accept sea lice on seadragons in moderation;
Watch your feet and fins;
Take special care with male seadragons carrying eggs;
Turn the lights down when observing at night;
Clean up discarded fishing line found;
Dive right and watch your gear;
Respect the marine environment;
Remember fisheries regulations; and
Respect marine reserves.”
Hope that this all helps.
The following request came from Robin Sharp in April 2005.
“Subject: Marine Plan rare species Upper Spencer Gulf
Appreciate if you could email me back some information on the following species. Apparently they are a relic species of interest within the Upper Spencer Gulf Marine plan. I would like to obtain a photograph of these in order to better understand what they actually are. Can you help?
1) A flatworm (ancoratheca sp.)
(2) A nudibranch (Discodoris sp.)
(3) An ophiuroid (Amphiura sp.)
We sent the following reply to Robyn: -
1) Flatworms are Polyclads (Order Polycladida). They belong to the Phylum Platyhelminthes. There is a chapter (Chapter 5) about them in the book ”Marine Invertebrates of Southern Australia – Part 1” edited by SA Shepherd & IM Thomas. Ancoratheca australensis is the first species described in the chapter. It is said to be recorded from upper Spencer Gulf. The brief description says that the body is “oval, of firm consistency, to about 10mm long. Dorsal surface light brown, dappled with dark spots, except anteriorly and marginally where body is whitish. Very small marginal eyes; minute eyes spread fanwise over cepahalic region to merge with marginal eyes”. A few specimens of flatworms are pictured in the book – plates 22.4, 22.5, 22.6 23.1. One book that specializes in Polyclads is “Marine Flatworms, the World of Polyclads” (author unknown) which is available for $39.95 (+ postage) from firstname.lastname@example.org .
2) Nudibranchs are an Order of ophistobranchs (sea slugs) – Order Nudibranchia. Dorid nudibranchs are a Family of nudibranchs – Family Dorididae. Discodorids are included in the Dorid family. Three species of discodoris are pictured in Neville Coleman’s book “”Nudibranchs of the South Pacific” (pages 22 –3). This book is also available from email@example.com at the price of $16.50.
3) Ophiuroids are brittlestars, a class of starfish. Brittlestars belong to the Class Ophiuroidea. The book ”Marine Invertebrates of Southern Australia- part 1” edited by SA Shepherd & IM Thomas lists several species of Amphiura brittlestars (belonging to the Family Amphiuridae) on page 437. Only two of these species are described in the book – Amphiura constricta & Ophiocentrus pilosus (on page 425). Amphiura are said to have “two squarish papillae at apex of each jaw”. Amphiura constricta is said to have “one erect distal oral papillae on each side of each jaw, separated from the tooth papilla by a wide gap (Fig 10.15e on page 427). It is said to be “A widespread and common species growing to 7mm disc diameter, with arms up to 45mm long. The disc is fully scaled above and below, and the arms bear 6-8 short spines on each segment. The tentacle pores are covered by a single, large oval scale, and there is one distal oral papilla on each side of the jaws. The radial shields are longer than wide, separated and divergent. The disc is grey and the arms are banded light and dark. The species lives in algal turf and amongst bryozoan and sponge rubble”.
Ophiocentrus pilosus is said to have “one or two squarish apical oral papilla and one or two distal papillae” and “Disc scales bearing simple short spinelets, no tentacle scales” (Fig.10.15c on page 427). It is said to be “A large simple-armed brittlestar gowing to 18mm across the disc with arms 140mm long. It is characterised by having a Amphiura-type mouth structure, with tall distal oral papilla on each side of the jaws, but it is also completely lacks tentacle scales, and its disc is covered with small scales and numerous short spinelets. It has up to 10 somewhat flat-tipped arm spines on each segment, and the lowermost are the longest. A soft sediment dweller, this species is known mostly from SA to NSW”.
Our Photo Index of SA Marine Life features a few photos of flatworms, dorid nudibranchs and brittlestars. These photos can be viewed on our web site at www.mlssa.asn.au - flatworms on pages 16 & 17, dorid nudibranchs on pages 1-3 and brittlestars on pages 8 & 9.
Much of the above details are very involved but we trust that it helps a little.
This request came from Des Fuller in March 2005: -
I have been trying to find out some info on the life cycle and growing time for Razor fish. We collect them (to eat) each year on our holidays on Gulf St Vincent in SA. But there are a lot of small ones and we wonder how fast they grow, etc... Any info would be gladly received.
Yours in nature,
We sent the following reply to Des: -
It has been suggested that razorfish are now threatened or endangered. Sorry that we cannot help you re life cycle, etc.. Suggest that you contact SARDI at firstname.lastname@example.org .
Des soon replied as follows: -
Thanks for your referral to SARDI. Suzanne was very helpful and has sent me some papers on the findings of surveys done in Gulf St Vincent, and it has answered all our questions.
That last enquiry had been the second recent one regarding razorfish. In September 2004 Adam Browne had sent us an email request. These details were published in our March 2005 Newsletter (No.319): -
I hope you don’t mind general enquiries; I'm looking for information on razorfish, which I'm told are a kind of shellfish that lives in South Australian waters. I was wondering if there's anything you could tell me about their distribution around the Australian coast, especially here in Victoria, and whether they are an endangered species or are allowed to be fished.
We sent the following email reply to Adam: -
You are correct about razorfish being a kind of shellfish that lives in South Australian waters. It seems that they occur across southern Australia from WA to NSW, usually in seagrass beds or sand flats in bays and estuaries. They are not considered to be an endangered species and they are allowed to be fished in SA. There are, however, bag limits for the species Pinna bicolor in SA waters. The department responsible for SA’s fishing regulations, Primary Industries and Resources SA (PIRSA), currently applies a bag limit of 50 for this species and a boat limit of 150. Check with your own State’s authorities for fishing regulations in Victoria. Below are some more details about razorfish: -
Razorfish are marine bivalve molluscs from the family Pinnidae. They are also known as Pinna, Razor-shells, Pen Shells and Fan Shells. A simple description of razorfish can be found in “Seashells of the World” (A Golden Guide). This little book says that they are “large and fragile, live in soft sand anchored by a silky byssus”. A byssus is a tuft of dark brown threads*.
A more complicated description about them is found in “Molluscs” by JE Morton. This book says that “They have long and wedge-shaped equal valves, and are unique in being embedded upright in the sand and secured there by a byssus. Each byssus thread is attached to a sand particle, and the whole structure gives great stability in a soft substrate. The fan shell is immobile and the foot and anterior end are greatly reduced. The posterior or uppermost part of the shell is broad and triangular, composed of horny conchiolin, only thinly calcified. There is a wide mantle gape at the broad end, with thickened lips, and, . . . there are efficient ciliary and mucous tracts for cleansing the mantle cavity of sediment. The greater part of the mantle in Pinna is free of attachment to the shell, and its edges can be deeply withdrawn and protected from injury by special pallial retractor muscles”.
The book “Australian Seashores” by Isobel Bennett says that the Pinna are known as razor-shell because of their sharp (ventral) edges. When these sharp edges are all that protrudes from sand they can cause serious injury to bare feet.
*The original version of “Australian Seashores” by WJ Dakin gives more information about razorfish and quite some details about the byssus. It refers to the byssus as “a curious bunch of anchoring threads”. It goes on to say that “The production of this byssus is a function of the foot found only in bivalve molluscs. The byssal threads are secreted by a gland in the foot, which thus becomes an organ for attachment”.
We hope that this information helps.
Marine Life Society of SA”
Other request details that have been published in our Newsletter include the following one received in October 2003 about a Catfish sighting at the Port Noarlunga Reef. The enquiry was sent on to us by James Brook. It was published in our March 2004 Newsletter (No.308): -
I'm not sure if this is of interest to you or Reefwatch, but I'll let you know in case it is. On a night dive at Noarlunga Reef last night we saw an unusual fish (we thought was unusual anyway). At first we I thought it was a rock ling but it had more than two barbels (and I think more than four as well). I believe from my fishing book that it was an Estuary Catfish (Cnidoglanis macrocephalus) as the body was more rock ling shaped than the more stout bodied eel-tailed catfish (which is freshwater anyway). I just thought that this was an unusual sighting as Noarlunga reef is neither an estuary or brackish water which I believe they are found in. Also, according to the species location in my book, they are found in Queensland / Victoria and Western Australia. They're probably very common here but I haven't seen one before. Also it was about 1-1.2m, so quite big as well. We found it about 100-200m north of the jetty. If you can give me any feedback on whether this is an estuary catfish, and how common they are around here, I would appreciate it. Is there a database that this type of thing goes onto, on the website, or do I just email you the info? Hope this is of some use.
James wanted a response from me and so I sent him the following email reply: -
I keep my own database of fish sightings at Port Noarlunga reef. I have recorded Estuary Catfish for the area. These are a marine species and they can be quite large. They occur in estuarine and coastal waters. They should have 8 barbels on their head. Max size is said to be just 91cm. Everything underwater looks 1/3 bigger i.e. 1.2m.
Philip Hall reminded me of various articles published in our Newsletters and Journals so a later email (to Nick?) read: -
Further to my last email re your catfish sighting, David Muirhead has written an article about a catfish sighting at Port Noarlunga. See the article “A Footbridge Too Fra” in either our December 2000 MLSSA Journal or our March 2003 Newsletter. Both publications can be viewed on our web site at http://www.mlssa.asn.au .
Then there was a request for information about Moonlighters. Details were published in our July 2004 Newsletter (No.312): -
“ We recently received an email requesting information. It read: -
I am trying to identify certain species of fish that may change their sex from either male to female or otherwise, during their lifetime. Does the Moonlighter come into this category? I do believe that it comes in the category of SEXFASCIATUM ? Does this mean they are capable of this transaction?
Any information would be valuable in my studies.
San Remo, VICTORIA
I sent off the following reply: -
Re. your enquiry about the Moonlighter changing sex. I have not heard of this occurring in Moonlighters. I note that you are intrigues over the scientific name of Vinculum seaxfasciatum. Anearlier name for the same fish was Chaetodon sexfasciatus. But none of this has anything to do with changing sex. It’s like the NZ version of six. Sex is actually Latin for six. In this case it probably refers to the six bands that give the Moonlighter its other name of Six-banded Coral Fish. We would love to hear of your findings regarding other fish that change sex.
You may have noticed that we receive enquiries from SA, interstate and overseas. The following message came from overseas on 16th May 2005:-
I am currently studying in the ENITA of Bordeaux in FRANCE (a university level agricultural institute awarding a five year degree equivalent to a Master of Science) and I’m looking for a 2-3 month internship in Australia for this summer 2005 (between early June and early September).
I have done some research over the internet and with some of my colleagues/teachers in order to find contacts and information to do this internship. I am quite interested in your organization, its research domains and the research you are currently working on.
This internship is required by my school but the subject is of my own choice and thus I would like to improve my theoretical and practical knowledge of marine biology (reefs, animals and plants) or aquaculture (any kind of fisheries: fish, sea shells, molluscs, etc). I would therefore like to join an existing research and/or development team in one of those domains in order to try to help in field studies and results analysis and interpretations.
Please find attached my Curriculum Vitae (better seen without table gridlines), and it would be wonderful if you could find a placement for me. I speak fluent English and I am prepared to take care of travel expenses and living expenses in Australia if necessary.
Thank you for your help.
We sent the following reply to Jeremy: -
The MLSSA consists of volunteers only. Any one is able to become a member and join in our activities if that is any help to you.
This enquiry came in from overseas on Wednesday 25th May 2005 (at 5:00AM!).
“My name is Susan Hieter and I am currently teaching at Kutztown High School in Kutztown, Pennsylvania for the past 12 years. This summer (end of July 2005) I will be taking a science teaching at the International School of Aruba teaching all the sciences from grades 7 to 12. The school was taken over by the International School Services out of Princeton, New Jersey about 2 years ago. The school has students from the United States, Canada, the Netherlands, the United Kingdom, South America, the Caribbean, etc.
I am writing to you to get any resources and/or ideas that I may take with me to help with the students in developing the programs of science. Specifically, marine science, which will be taught to the 11th and 12th grade students. I am also looking to start a scuba club where we can monitor the reefs and their environment. I would appreciate any and all materials that you can send me. Also, the school and myself would be very interested in becoming members of your organisation. If you have any suggestions or comments, please email me or send me information. I have enclosed my new school address (as of July 25, 2005) and my home address (until July 18, 2005). Thank you so much for all of your help and effort. I hope to broaden the students minds with this information.
Susan B. Hieter
Science Teacher (7th-12th grade)
International School of Aruba
Aruba "Dutch Caribbean"”
We sent the following reply: -
“Hi Susan (Scuba
Scuba Steve here. Great to hear from you. Re becoming a member of the Marine Life Society of SA, that would be impractical. You could, however, maintain contact with us by regular reference to our web site at http://www.mlssa.asn.au . You will find our monthly newsletters and annual journals posted there. Other pages on our site cover our annual calendars of SA marine life, our Photographic Index of SA marine life and our library, plus lots more. We suggest that you contact Reef Watch at the above address to find out more about reef monitoring. Please keep in contact and let us know how you get on. Good Luck.
Susan (Scuba Sue) soon sent a message back to Scuba Steve as follows: -
“Hi Scuba Steve,
Thanks for the info and I just emailed Reef Watch. Thanks again and I'll let you know how things work out. It might be a while since I probably will be going a little crazy the first few months.
On 4th June 2005 the following message was sent to us from overseas: -
My name is Alessandra Tomasini and I´m an Italian biologist graduated to the Universitá degli Studi of Genoa. I´m looking for a proficiency and interesting opportunity abroad in marine biology. During university I conduct a field research project on bottlenose dolphin in Genoa´s water for my thesis and now I´d like to continue on this way in order to gain more experience on research techniques. I´m available for stage, internship, PhD on population dynamic, ethological studies or everything else on marine field. Can your organisation give me this opportunity? What (do) I have to do in order to obtain this possibility?
Thank you in advance.
We sent the following reply to Alessandra: -
Members of the MLSSA are all volunteers. As a member you would be able to join in our activities or involve us in your own. We do have dolphins on hand and also members working with dolphins. You can find out more about our Society at http://www.mlssa.asn.au .
It is pleasing that we are able to help people out with their enquiries regarding marine life topics. It is good to see (hear?) that there is considerable worldwide interest in marine life by the public.
by Philip Hall
Subject: Fiddler Ray Photo.
I am writing to request the use of one of your photos of a Southern Fiddler Ray. The one on your website that most appeals to me is 1258.jpg. If you have others available that I could preview, I would be interested in comparing them to 1258.jpg.
I am the Curator of Aquatic Life at the Pittsburgh Zoo & PPG Aquarium. The Pittsburgh Zoo & PPG Aquarium is a private non-profit organization dedicated to the conservation and education of wildlife. We have recently renovated a stingray exhibit so that it is now a touch tank. In combination with that, we have incorporated a PowerPoint slide show projected onto the wall behind the exhibit that shows the different species in the tank. We have a couple of Fiddler Rays that are soon to be added to the exhibit and so I am looking for a nice image to include in the slide show.
As it is a computer projector generating the images on the wall, the image we would be looking for would only need to be of a medium resolution (i.e. around 1 Meg file size) as that is the limits of the projectors resolution.
Please let me know what would be involved from our part to acquire that image. Thank you very much and I look forward to hearing from you.
Very truly yours,
Curator of Aquatic Life
Pittsburgh Zoo & PPG Aquarium
My reply read as follows:-
The Committee agreed to your request and the picture will be scanned and sent to you by another member.
We do feel that touch tanks are not the most suitable way to educate the general public and ask that their use be discontinued as soon as possible. We can give detailed explanations if needed.
We would appreciate a note that MLSSA supplied the picture somewhere with perhaps a reference to our website address and ask for $25 Australian as our usual copyright fee for non-profit organizations be sent by electronic transfer. (The supplier of the picture will advise you of the bank account details.)
Philip Hall (President)
This was the prompt reply from Allan:-
Thank you very much for the usage of the photo. I completely understand your reservations regarding touch tanks. Please allow me to try to allay your fears regarding the animals’ welfare.
I am not sure what types of “touch tanks” you and the members of your committee have seen before. There are small versions in public aquariums that usually only contain a few invertebrates that have no opportunity to escape handling by the public. I agree that these can be quite stressful to the animals and that is certainly not the design or intention of our exhibit. The tank shape and size, life support systems and monitoring by staff and volunteers are specifically designed to ensure the safety and health of the animals for the long term.
This particular tank is about 5 meters by 4 meters in horizontal dimensions and about 80cm deep. At one end there is a shallow section that is about 40cm deep. People have access to only two sides of the exhibit. The design is such that the stingrays are only gently touched if they choose to swim or sit in the shallow area at one end. If they do not wish to be touched, they have ample room to swim and/or lay on the bottom undisturbed. We currently have five species on exhibit and they have all been doing very well. Some of the rays have been in this exhibit for over five years while others have been introduced over the past year to increase the species diversity. Some species are less inclined to be patted and tend to spend most of their time out of reach of our visitors, while others actually spend most of their time hanging around in the shallows for the attention. Of course, we also have an attendant at the exhibit at all times that it is open to monitor both the public and the animals to be sure that there is no abusive contact.
Considering that Pittsburgh is so far from the coast, there many people from the region who have never seen the ocean and would never have an opportunity to get close to marine life and make that “connection”. As you can imagine, it is difficult to encourage conservation of the oceans when our visitors are so far removed from the issues that face you and so many others that live on or near the shore (I’m from Brisbane originally and grew up around Moreton Bay and the Sunshine Coast – yes, I miss it a lot!). The chance to touch a stingray is something that many of our visitors are enthralled by and they keep that experience with them for many years. The PPG Aquarium as a whole, and the stingray exhibit particularly, is a great tool for changing peoples attitudes and making them aware that their actions do affect more than just their local surrounds.
Thank you again for your help with the image. I look forward to receiving it and will ensure swift payment when the account details are sent to me.
The next one was a worry and entailed many email and much phone activity by me. I will include just a few email items:-
I am writing to you in the hope you can give me a contact number for someone who could help an orphaned baby seal at Seal Bay on Kangaroo Island.
My daughter has just phoned me after visiting Seal Bay, very distressed because they saw a baby seal there which had lost its mother and the rangers said it was not their role to intervene. They would simply watch it starve to death which would take about a week.
She is at the moment flying back to Adelaide but is desperate to find some way to help this animal. I am in Brisbane so I have no knowledge of organisations working at Kangaroo Island.
Surely if the rangers cannot do anything else, they would ensure the animal died as quickly and humanely as possible and not watch it starve to death.
I do hope you can suggest a contact number for me.
Thank you so much
I sent out a general email to MLSSA members:-
What do you suggest MLSSA advises in a situation like this?
Alex Gaut replied:-
I believe that Parks has a policy of no intervention (but I’m not sure). If we could check this, then I believe it is MLSSA’s place to reinforce this policy with the public. I can understand that this would cause distress for many people, but if Parks start making exceptions then they have to do it every time and cracks start appearing in the policy.
My own personal ethics would agree that the cub should be killed quickly, but I believe that Parks policy should be checked.
If MLSSA as a whole does not agree with Parks policy then perhaps we need to do something about that.
Vice President, Marine Education Society of Australasia
0418 921 849
After making enquiries with Parks and Wildlife on KI I then corresponded with Marjorie Rayment and her reply is below:-
Thank you for your reply.
Elizabeth phoned the RSPCA and was told there was an arrangement for the rangers to contact them if there was a seal that needed rescue.
A person who I believe was a chief ranger also phoned Elizabeth and said the rescue facility that was usually used was now not available because of the incidence of kennel cough.
The people in the group were shocked to hear the ranger say they would watch the seal starve to death and that it would take about a week. We have always believed rangers had a policy of humane treatment of animals and that if there was no hope for an animal to survive the rangers would end its suffering as quickly as possible.
It is not acceptable to say they do not interfere with the balance of nature. We all understand those principles, but we interfere with the balance of nature all the time - including culling the koalas on the island!
We have seen many documentaries about seal rescues, so we know there are people who rescue seals. I had gone to the web hoping to find information about a rescue group covering Kangaroo Island.
Elizabeth and her party will leave Adelaide tomorrow (Monday) night probably without knowing whether anything has been done to rescue the seal. We will continue to contact people to try to follow up what has happened.
Thank you again for your reply
Now follows an email from John Hill MP:-
Dear Mr Hall
Thank you for your email of 7 March 2005 concerning a sealion pup at Seal Bay as reported to you by Ms Marjorie Rayment.
The pup in question continues to be monitored in relation to its health and well being and, at last report, the animal was observed to be alert, active and feeding.
Seal Bay is home to a colony of wild Australian Sealions. As such, these animals are exposed to the hazards and risks that face all wild animals.
Sealion mothers leave their pups on the beach and undertake foraging trips up to 60km out to sea for approximately 72 hours duration. Pups are left to their own devices during their mother’s absence and quite often interact with other animals in the colony including some limited surrogate feeding activity. At times mothers may be absent for extended periods well beyond the typical 72 hours, with some recorded absences of over two weeks. Pups may struggle during these absences, but successful rearing has occurred following the mother’s return when pups suckle consistently for the three to four days the mother is ashore. Consequently, determining whether an animal has been “orphaned” or not is very difficult. The mother rearing and educating the pup achieves the best chance of pup survival and successful interaction and breeding in the colony.
Despite this difficulty, all necessary practices and procedures are followed in relation to obligations under the National Parks and Wildlife Act 1972 and the Prevention of Cruelty to Animals Act 1985. Animals that have been in serious difficulty in the past, have been humanely destroyed, however, there are also numerous examples of sealions fully recovering following a serious mishap.
While I am disappointed that Ms Mayne’s experience at Seal Bay was not as positive as she had hoped, I am satisfied that the concerns raised by Ms Mayne, Ms Rayment and you are being appropriately addressed by Department for Environment and Heritage officers.
Thank you for your interest in this matter.
Following a talk on local marine life Margaret and I gave to the Yankalilla Probus Club I was asked if I could identify an item found on the local seashore. A few days later the following picture was emailed to me.
The object was described as having a waxy feel and I thought it might be Ambergris which is found inside whales. These animals pass nearby quite frequently. I contacted a firm in New Zealand which buys and sells ambergris and they were very doubtful.
The next step will be to see if the finder will be willing for me to take it to the South Australian Museum to one of the experts there. An ongoing quest at the time of writing.
The unidentified object