Scylla serrata

Super Group: 
Opisthokonta
Phylum: 
Arthropoda
Sub-Phylum: 
Crustacea
Class: 
Malacostraca
Sub-Class: 
Eumalacostraca
Order: 
Decapoda
Sub-Order: 
Pleocyemata
Family: 
Portunidae
Sub-Family: 
Portuninae
Genus: 
Scylla
Species: 
serrata
Authority: 
Keenan, Davie & Mann 1998 (Forskål 1775)

Diagnosis

Diagnosis_Genus: Scylla de Hann 1833. Carapace oval, wider than long (CL/ICW range 0.66-0.72); moderately convex, surface smooth, gastro-cardiac grooves poorly to moderatly well defined; front clearly separated from supra-orbital angles, divided into four teeth ranging from low rounded lobes to prominent sharp spines, frontal width variable between species (FW/ICW range 0.33-0.45); anterolateral margins convex, bearing nine similar-sized teeth, longer than smooth posterolateral margins; supra-orbital margin with closed median and outer fissures; infra-orbital margins prominently toothed; antennules folded nearly transversaly; basal antennal article produced into the orbit, flagellum lying in the orbital hiatus. Chelipeds massive, smooth, longer than legs; merus with three large spines and anterior border, two smaller spines onposterior border; carpus with acute tooth at onner angle, 1-2 spines an outer margin varying from strong to obsolete; propodus with strong spine at carpal articulation, a pair of dorsal spines above base of dactyl varying from strong to obsolete, inner face with a large tubercle immediately behind base of gape. Legs stout, moderatly compressed, first three pairs similar, fourth pair natatorial. Male abdomen narrow, segments 3-5 fused; female abdomen broadly oval. Colour variable, with or without polygonal patterning.
Diagnosis_Species: Frontal lobe spines high (mean height c 0.06 times frontal width measured between medial orbital sutures), blunty pointed with tendency to concave margins and rounded interspaces. Anterolateral carapace spines narrow, with outer margin straight or slighly concave. Carpus of chelipeds with two obvious spines on distal half of outer margin, palm of cheliped with a pair of disctint psines on dorsal margin behond insertion of the dactyl. Chelipeds and legs all with polygonal patterning for both sexes and on abdomen of female only. Male first gonopod as in Fig. 9A. Colour variable from purple through green to browny/black depending on habitat. Means and standard deviations of the most important morphological ratios for species discrimination are presented in Table 4.

Etymology

Gender feminine.

Type species

This is the type species of the genus. (described as cancer serranus by Forskal 1775).

Type illustration / Type locality / Type specimen

Type locality: Danmark
 

Ecology

Associated with mangrove forests inundated with full salinity oceanic water for the greater part of the year. Can tolerate reduced salinity.
This is the most widespread Scylla species. It occurs naturally throughout the Indo-Pacific, from South Africa to Tahiti, north to Okinawa, and south to Port Hacking in Australia, and the Bay of islands, New Zealand (Mc Lay, 1988). There is also a report of the species from the South Atlantic Ocean off Brazil (Melo, 1983), although there is no evidence that it has viable populations there.
Salinity: marine
Salinity: variable

Observation site(s)