Patterns in the distribution of the crinoid community at Davies Reef, central Great Barrier Reef

Brief description

Surveys of the diversity and distribution of crinoids were conducted on Davies Reef between 1981 and 1983.A total of 25 fives sites were sampled within 5 habitat types. The habitats sampled were the reef slope, reef crest, moat, lagoon and back reef. The reef slope was further divided into three depth habitats (5m, 10m and 15m). The reef crest was sampled at 0m and the moat, lagoon and back reef were sampled at 5m.A sampling site consisted of 25 adjacent 1m² quadrats along a depth contour on the reef. Four replicate sampling sites were examined in each habitat, except for the 15m reef slope habitat. Within each quadrat, all crinoids on the surface and those occurring within the substrate, to a depth of about 50cm, were recorded. The position of each crinoid within the quadrat was recorded and crinoids collected for later preservation and identification in the laboratory.Habitats were also ranked with respect to the following external factors: current, energy, depth, sediment and coral cover. This research was undertaken to determine the structure of the crinoid community at Davies Reef by investigating species diversity and distribution across a variety of reef habitats. This allowed comparisons with other reef communities, such as coral, fish and sponges from the same reef.This survey was also used to establish suitable field and analytical techniques to enable more intensive local distributional studies and more extensive between-reef studies. Extensive taxonomic revisions of some of the comasterid genera were published in: "Rowe FWE, Hogget AK, Birtles RA and Vail LL (1986) Revision of some comasterid genera from Australia (Echinodermata: Crinoidea), with descriptions of two new genera and nine new species. Zool J Linn Soc 86:197-277." New species names from this publication are included in the following list of crinoids identified.Crinoid species identified from within quadrats: Comasteridae:Comanthus parvicirrusComanthus samoanus = Comanthus sp. cf. C. wahlbergii (J. Muller)Comanthus sp. AComasterinae n. gen. n. sp. A = Oxycomanthus mirusComasterinae n. gen. n. sp. B = Oxycomanthus exilisComanthina schlegeliComantheria alternansComantheria briareus: to be included with Comantheria alternansComanthus luteofuscum = Clarkcomanthus luteofuscumComanthus timorensis = Clarkcomanthus littoralisComaster multifidusComaster gracilisComatella nigraComatella stelligeraComatella maculataComatula purpureaComissia pectiniferaColobometridae:Cenometra bella Petasometra claraeMariametridae:Stephanometra oxyacantha Tropiometridae:Tropiometra afraAdditional species collected outside quadrats:Comasteridae:Comanthus bennetti = Oxycomanthus bennettiComanthina sp. A = Comanthina nobilisComantheria n. sp. A = Comanthus mirabilisCapillaster multiradiatusColobometridae:Colobometra perspinosaOligimetra serripinna

Lineage

Maintenance and Update Frequency: notPlanned

Statement: Statement: Specimens were identified using the following keys:Clark AM and Rowe F (1971) Monograph of shallow-water Indo-West Pacific echinoderms. Brit Mus Nat Hist Publ 690.Rowe FWE, Hogget AK, Birtles RA and Vail LL (1986) Revision of some comasterid genera from Australia (Echinodermata: Crinoidea), with descriptions of two new genera and nine new species. Zool J Linn Soc 86:197-277.

Notes

Credit
Bradbury, Roger H, Dr (Principal Investigator)