Australian Biological Resources Study

Australian Faunal Directory

<em>Ceratocarcinus longimanus</em> [from Adams & White 1848]

Ceratocarcinus longimanus [from Adams & White 1848]


Regional Maps

Subfamily Eumedoninae Dana, 1853


Eumedonines live symbiotically on and within echinoderms. Several records of their presence on sponges and soft corals require confirmation, and are probably a result of dislodgement from the hosts during collecting. Eumedonines can be relatively common on tropical reefs, but they are mostly small (typically around 1 cm carapace length), and their cryptic habits mean that they are seldom encountered or collected. Species are often, but not always, host specific. Of the 11 genera currently recognised, ten occur in Australian waters, with one, Zebridonus Chia, Ng & Castro, 1995, apparently indigenous to the Gulf of Carpentaria. In an important recent paper, Chia & Ng (1998) revised Ceratocarcinus White and Harrovia Adams & White, created three new genera, and provided keys to all taxa. Ng & Clark (2000) reviewed adult and larval characters of the Eumedoninae and made a strong argument for its inclusion as a subfamily of the Pilumnidae, although earlier it had been treated as a family in its own right (Stevcic et al. 1988).



Carapace subpentagonal or subhexagonal; nearly flat, sometimes bearing pointed tubercules; regions more or less indistinct; junction between antero- and posterolateral margins usually well marked, often with a spine. Front projecting, bilobed or quadrilobed, rarely emarginate. Orbits circular, small, well defined; orbital hiatus filled by basal antennal segment. Antennae small, basal antennal article largest; flagellum short. Epistome wide, short; buccal cavity quadrangular, completely covered by third maxillipeds. Chelipeds moderate sized, subequal; ischio-meral suture fused, but distinct; chelipeds and walking legs often armed with spines or cusps. Walking legs with dactylo-propodal articulation formed by rounded prolongation of propodal lateral margin sliding against and beneath proximal projecting button on lateral margin of dactylus. Male genital opening coxal; female genital opening sternal. Male abdomen not elongate, not reaching level of anterior edge of base of chelipeds; telson not elongate, not twice length of segment 6. Male first gonopod long, slender, sinuous, hooked apically; second gonopod very short, sigmoid.


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)