Coleusia biannulata
Scientific Name:-
Coleusia biannulataCommon Name:-
Purse Crab
Malayalam Name:-
Purse Njandu
Category:-
Crabs
Status:-
Not evaluated
Description:-
Carapace is highly polished, somewhat pyriform and are slightly longer than broad. Dorsal surface of carapace closely punctate, punctae larger anteriorly. Frontal margin unidentate. Epibranchial margin with large, elliptical granules. Anterolateral margin of carapace sinuous, bearing closely spaced flattened granules; increasing in size posteriorly. Posterolateral margin evenly beaded, granules ending above first pereiopod. Epimeral margin gutter-like anteriorly, narrowing posteriorly, marginal granules decreasing in size posteriorly, meeting posterior margin at a rounded angle. Posterior margin sinuous, minutely granulate; beneath this posterior surface smooth. Two large ocelli present on the gastric region with small white centers and very broad red outer rings. Pereiopods are slender and banded red. The fingers of the claw with their basal halves red and the distal halves white. Thoracic sinus with row of four or five perliform granules above cheliped basis, decreasing in size posteriorly. Sinus anteriorly defined by obsoletely granulate, rounded, overhanging margin of pterygostomian region. Thoracic sternites punctate. Lateral margins of fused abdominal segment in male subparallel, narrowing evenly, segment bearing small denticle; telson lingulate. Cheliped merus half as long as carapace, its dorsal surface proximally with perliform granules, distally punctate; anterior surface with large perliform granules proximally, rounded granules distally; posterior margin with large perliform granules, diminishing in size posteriorly. Carpus with row of granules on inner margin. Propodus granulate in lower surface; row of larger granules on inner margin. Merus of pereiopod bear single granulate line on upper margin, two beaded lines ventrally. Carpus of pereiopod rounded, smooth; propodus dorsally and ventrally carinate. First pleopod in male with outwardly curved apical process. The chelipeds and pereiopods are all intercalated with red bands
Remark:-
Bijukumar et al. (2013) and Sushilkumar (2013) recorded it from the trawl by-catch along Kerala coast.
Habitat:-
Sandy soft bottoms.
Synonyms:-
Leucosia longifrons var. neocaledonica Alcock, 1896;
Leucosia biannulata Tyndale-Biscoe & George, 1962;
Tirmizi & Kazmi, 1988;
Leucosia longifrons Chhapgar, 1968;
Coleusia biannulata Galil, 2006.
References:-
Biju Kumar, A., Sushil Kumar, M, and Galil, B.S. (2013). Calappid and leucosiid crabs (Crustacea: Decapoda: Brachyura) from Kerala, India, with the description of a new species of Mursia Desmarest, 1823, from the Arabian Sea and redescription of M. bicristimana Alcock & Anderson, 1894. Zootaxa, 3746 (4): 529-551.
Sushilkumar, M. (2013). Diversity and proximate composition of brachyuran crabs in the trawl by-catch of Kerala coast. PhD Thesis submitted to University of Kerala, India.