Australian Biological Resources Study

Australian Faunal Directory

<em>Trapezia cymodoce</em> [P. Davie 2002: 493]

Trapezia cymodoce [P. Davie 2002: 493]


Regional Maps

Family TRAPEZIIDAE Miers, 1886

Compiler and date details

May 2012 - Peter Davie, Queensland Museum, Brisbane


Trapeziid crabs are obligate associates (symbionts) of cnidarians. The best known are species of Trapezia that live in branching corals of the family Pocilloporidae (Pocillopora, Seriatopora and Stylophora species). Quadrella species are recorded more rarely; they live on alcyonaceans, antipatharians, and ahermatypic scleractinian corals. Trapeziidae are mostly restricted to the Indo-west Pacific region, although a few species also reach the tropical eastern Pacific.

The taxonomy of many of the common trapeziids has been in a state of confusion for many years because morphological differences between species are relatively minor. Identification is best based on colour differences that are often lost in spirit-preserved material. Important modern works are those of Patton (1966), McNeill (1968), Serène (1984), Galil & Lewinsohn (1985), Galil (1988), and Castro (1997, 1999). Ecological studies of Australian trapeziids include those of Patton (1974, 1994), Lassig (1977), Austin et al. (1980) and Abele (1984).

Serène (1984) considered the Trapeziidae to comprise two subfamilies: Trapeziinae and Domeciinae. The latter, represented in Australia by the genus Domecia, is here considered a family in its own right. Most recently Tetralia and Tetraloides that live on Acropora coral species, were recognised as belonging to a separate morphologically convergent lineage, and both genera were separated off into a separate family, the Tetraliidae Castro, Ng & Ahyong, 2004, under the Superfamily Trapezioidea.



Carapace more or less flattened, subquadrilateral, pentagonal or transversely oval; dorsal surface smooth or finely granular, regions not marked or sometimes indicated feebly; setae absent. Front almost straight; four lobes or teeth or bilobed; sometimes finely denticulate. Basal antennal joint slender. Antennules folding transversely. Eyes moderately large, exposed, not well protected by orbits. Crests of endostome defining efferent channels well developed. Third maxilliped with merus shorter than ischium, but not much broader than long. Second maxilliped with endopod composed of four distinct segments (merus, carpus, propodus, dactylus). Chelipeds long or very long, meri projecting beyond carapace when folded; slightly to moderately unequal, surface of palm smooth or finely granular. Walking legs with a dactylo-propodal articulation formed by a rounded prolongation of propodal lateral margin sliding against and beneath a projecting button situated proximally on lateral margin of dactylus. Male abdomen 5-segmented, segments 3–5 fused but sutures sometimes visible. Male genital openings coxal; female openings sternal.


General References

Abele, L.G. 1984. Biogeography, colonization, and experimental community structure of coral-associated crustaceans. pp. 123-137 in Strong, D.R., Simberloff, D., Abele, L.G. & Thistle, A.B. (eds). Ecological Communities: Conceptual issues and the evidence. Princeton, N.J. : Princeton University Press.

Austin, A.D., Austin, S.A. & Sale, P. 1980. Community structure of the fauna associated with the coral Pocillopora damicornis (L.) on the Great Barrier Reef. Australian Journal of Marine and Freshwater Research 31: 163-174

Castro, P. 1997. Trapeziid crabs (Brachyura: Xanthoidea: Trapeziidae) of New Caledonia, eastern Australia, and the Coral Sea. pp. 59-107 in Richer de Forges, B. (ed.). Les fondes meubles des lagons de Nouvelle-Calédonie (Sédimentologie, Benthos). Études & Thèses. Paris : ORSTOM Vol. 3.

Castro, P. 1999. Trapeziid crabs (Crustacea, Brachyura, Xanthoidea, Trapeziidae) of the Indian Ocean and the Red Sea. Zoosystematica Rossica 21(1): 93-120

Castro, P., Ng, P.K.L. & Ahyong, S.T. 2004. Phylogeny and systematics of the Trapeziidae Miers, 1886 (Crustacea: Brachyura), with the description of a new family. Zootaxa 643: 1-70

Galil, B. 1988. Further notes on species of Tetralia (Decapoda, Trapeziidae). Crustaceana 54(1): 57-68 figs 1, 2

Galil, B. & Lewinsohn, C. 1985. On the taxonomic status of Trapezia areolata Dana and Trapezia septata Dana (Decapoda, Brachyura). Crustaceana 48(3): 286-293

Lassig, B.R. 1977. Communication and coexistence in a coral community. Marine Biology, Berlin 42: 85-92

McNeill, F.A. 1968. Crustacea, Decapoda & Stomatopoda. Scientific Reports of the Great Barrier Reef Expedition 1928-1929 7(1): 1-98 pls 1-2

Patton, W.K. 1966. Decapod Crustacea commensal with Queensland branching corals. Crustaceana 10(3): 271-295 figs 1-3 tables 1-4

Patton, W.K. 1974. Community structure among the animals inhabiting the coral Pocillopora damicornis at Heron Island, Australia. pp. 219-243 in Vernberg, W.B. (ed.). Symbiosis in the Sea. Columbia, S.C. : University of Columbia Press.

Patton, W.K. 1994. Distribution and ecology of animals associated with branching corals (Acropora spp.) from the Great Barrier Reef, Australia. Bulletin of Marine Science 55(1): 193-211

Serène, R. 1984. Crustacés Décapodes Brachyoures de l'Océan Indien occidental et de la Mer Rouge. Xanthoidea: Xanthidae et Trapeziidae. Avec un addendum par Crosnier, A.: Carpilliidae et Menippidae. Faune Tropicale 24: 1-400 figs A-C, 1-243 pls 1-48


History of changes

Note that this list may be incomplete for dates prior to September 2013.
Published As part of group Action Date Action Type Compiler(s)
04-Jun-2012 04-Jun-2012 MOVED
10-May-2012 10-May-2012 MODIFIED
12-Feb-2010 (import)