Sea spiders (Pycnogonida) from the Great Barrier Reef, Australia, feed on fire corals and zoanthids

1 Pages·2001·0.3 MB·English

by  Claudia P Arango

656 MEMOIRS OF THE QUEENSLAND MUSEUM
SEASPIDERS(PYCNOGONIDA)FROMTHF.GREAT these hosts, at least at the reefs visited. Observations made
BARRIER REEF, AUSTRALIA, FEED ON FIRE undercaptiveconditionsinthelaboratorywiththeaidofalow
CORALSANDZOANTHIDS.Memoirsof[theQueensland lightvideocameracorroboratedthesequenceofmovements
Museum 46(2): 656. 2001."-Tropical sea spiders have been observed in the field and more importantly, the ingestion of
scarcely studied and associations between pyenogonids and cnidarian tissue by the sea spiders. Some pyenogonids are
reeforganisms are rarely reported. The possibility of sea known to sequester and accumulate metabolites from prey,
spiders feeding on scleractinian corals had been suggested apparentlytobe usedasdefence(Sheerwoodetal., 1998). It
once (Child, 1998) but no evidence had been presented for remains to be studied whether this association between
eitherfirecoralsorzoanthidsasprey ofseaspidersbefore. Endeisspp.andcnidariansfromtheGreat BarrierReefcould
Thisnotereportstheoccurrenceandfeedingactivityofthe be chemically mediated, since Millepora and zoanthids in
pyenogonidEndeisonthe firecoral Milleporaexaesa(Class general, are known for their hieh concentration of toxins
Hydrozoa)andspeciesofZoanthidea(ClassAnthozoa)from Tl'ossa&Nilsen, 1998).
Rib Reef, Pandora Reef and Goold Island in the central Acknowledgments
section ofthe Great Barrier Reef. This is the first report on
coral reefsea spiders feeding activity, and is based on both Thanks to G. Diaz-Pulido for help with collecting and
fieldand laboratory observations. photography. I thank the Australian Institute of Marine
Adults ofEndeis mollis (32 individuals) were found on Science (AIMS) for providing access to the Great Barrier
different colonies ofMillepora exaesa (Fig. I) at Rib Reef Reefon boardthe RV Harry Messel.
{6-9m depth). On several occasions, the sea spiders were LiteratureCited
observedfeedingonthecoralinsertingthetipoftheproboscis CHILD, A. 1998. Nymphon torulum, new species and other
into a coral polyp and remaining attached for about 60 sec. PycnogonidaassociatedwiththecoralOculinavaricosaonthe
Individuals of E. mollis were also observed feeding on eastcoastofFlorida.BulletinofMarineScience63:595-604,
Palythoacaesia and crawlingon a Parazoanihus sp. at Rib l-OSSA,S.A.&NILSLN.A.J. 1998.Themoderncoralreefaquarium.
Reef. (BirgitSchmettkampVerlag:Bornheim).
Related Endeis biseriata, was found in the reef Hat of SHEERWOOD,J.,WALLS,J.T.&RITZ, DA. 1998.Amathamide
Goold Island and Pandora Reef(2-4m depth). Twenty-two alkaloidsinthepyenogonid,Styhpalienelongivmtda,epizoic
adultsof/:,biseriatawerefoundonProtopalythaasp.Similar onthechemicallydefendedbryozoan,Amathiawilsoni.Papers
feeding activity to that ofA', mollis was observed in some andProceedingsoftheRoyalSocietyofTasmania132:65-70,
MinidlTilvheiepdouarrlaeslaeotfxi£vae.esbhaiisgeahrnidantuaomfabteEb.rotbhoifssieEtre,is.amtoalloins tohne tzhoeanctohriadl ECcloaluodgiya,P.JaAmraensgoC,ooDkepaUrntimveernstitoyf,ZoToolwongsvyilalned 4T8r1op1i;ca8l
November2000.
Protopalythoasp.suggestapreferencebytheEndeisspp. for
FIG. I. Underwaterphotograph ofEndeismollis(Pycnogonida)on the tire coral Millepora