Kasim karubar, Ahyong, 2002

Ahyong, Shane T., 2002, Stomatopoda (Crustacea) of the KARUBAR Expedition in Indonesia, Zoosystema 24 (2), pp. 373-383 : 376-378

Kasim karubar n. sp.

( Fig. 2 )

TYPE MATERIAL. — Tanimbar Island, stn DW80, Arafura Sea, 09°37’S, 131°02’E, 199-201 m, 4.XI.1991, holotype tl 38 ( MNHN).

ETYMOLOGY. — Named for the KARUBAR Expedition, derived from the names of the Kai, Aru and Tanimbar islands; noun used in apposition.

DIAGNOSIS. — Eye with cornea asymmetrically bilobed. A1 somite dorsal processes directed anteriorly. A2 protopod without mesial or ventral papillae. Raptorial claw dactylus with five teeth. TS6-7 lateral processes each with posterolateral margin rounded, not produced posteriorly. AS 6 lacking submedian and intermediate carinae or spines. Telson dorsal surface smooth, lacking carinae; with low posteromedian projection terminating in blunt median projection flanked by three slender, well spaced, posteriorly directed spines above marginal armature; ventral surface with postanal spine, lacking carinae laterally.

DISTRIBUTION. — Known only from off Tanimbar, Arafura Sea, at 199-201 m depth.

DESCRIPTION

Eye with cornea asymmetrically bilobed, extending beyond A1 peduncle segment 1; cornea with mesial lobe rounded. Ophthalmic somite with anterior margin rounded. Ocular scales fused.

A1 peduncle 0.46cl. A1 somite dorsal processes directed anteriorly. A2 protopod without mesial or ventral papillae. A2 scale slender 0.37cl; entire margin setose.

Rostral plate with short, broad basal portion and long apical spine not extending anteriorly beyond cornea; dorsal surface smooth; ventral surface with carina. Carapace anterolateral angles broadly rounded; posterior margin unarmed.

Raptorial claw dactylus with five teeth; penultimate tooth slightly shorter than preceding tooth, outer margin faintly sinuous, proximal margin with basal notch; carpus dorsal margin terminating in short spine directed ventrally; propodus with opposable margin pectinate and with four movable spines proximally; merus outer inferodistal angle unarmed; ischium approximately one-third merus length.

Mandibular palp 3-segmented. MXP1-5 each with epipod. MXP5 basal segment lacking ventrally directed spine; merus with broad, evenly convex flange on inner margin.

TS5 lateral process obsolete. TS6-7 lateral processes subtruncate laterally, rounded anterolaterally and posterolaterally; posterolateral margin not produced posteriorly. TS8 lateral process rounded; sternal keel conical, apex blunt.

Pereiopods 1-3 basal segment with posterior, ventrally directed spine. Pereiopods 1-2 with distal segment of endopod subcircular; endopod 3 distal segment slender, elongate.

AS 6 smooth medially; lacking submedian and intermediate carinae or spines; lateral spines slen- der; with one slender spine and one broad triangular projection anterior to uropod articulation; sternum posterior margin unarmed.

Telson broader than long; with three pairs of primary teeth (SM, IM, LT); SM teeth with movable apices; IM teeth with apices extending posteriorly beyond base of SM teeth; with 10 SM denticles either side of midline; with four IM denticles, second and fourth longest; LT denticle spiniform; lateral margins unarmed. Dorsal surface smooth, lacking carinae; with low posteromedian projection terminating in blunt medi- an projection flanked by three slender, well spaced, posteriorly directed spines above marginal armature. Telson ventral surface with postanal spine; lacking carinae lateral to postanal spine.

Uropodal protopod terminating in two slender, flattened spines, dorsally and ventrally carinate, triangular in cross-section, inner longer; unarmed dorsally excepting dorsal spine above proximal exopod articulation; with slender ventral spine anterior to endopod articulation. Uropodal exopod proximal segment unarmed dorsally; inner margin with low, round distal lobe; outer margin with six movable spines, distalmost exceeding midlength but not apex of distal segment; distal margin with slender ventral spine. Exopod distal segment longer than proximal segment. Endopod unarmed dorsally; length 2.57 breadth.

Colour in alcohol

Completely faded.

Measurements of holotype

tl 38, cl 7.1, A1 peduncle 3.3, A2 scale 2.6, propodus length 6.2.

REMARKS

Kasim now includes three species, K. insuetus (Manning, 1970) from southern Australia, K. philippinensis ( Moosa, 1986) from the Philippines, and K. karubar n. sp. from Indonesia. Kasim karubar n. sp. most closely resembles K. philippinensis and both differ from K. insuetus in lacking a ventral papilla on the antennal protopod, lacking longitudinal carinae on the telson, and in bearing no more than four intermediate denticles on the telson. Kasim karubar n. sp. differs from K. philippinensis in bearing shorter, but asymmetrically bilobed eyes, fused instead of separate ocular scales, five instead of seven teeth on the dactylus of the raptorial claw, the posterolateral margin of TS6-7 is not posteriorly produced, and the posteromedian process of the telson is a blunt lobe instead of a slender spine. The three species of Kasim can be separated using the key below.

Species of four tetrasquillid genera have a postanal spine on the ventral surface of the telson: Acaenosquilla Manning, 1991 , Heterosquillopsis Moosa, 1991 , Kasim Manning, 1995 , and Tectasquilla Adksion & Hopkins, 1984 . Unlike other tetrasquillids, however, in Acaenosquilla , Heterosquillopsis and Kasim , the endopods of pereiopods 1-2 are subcircular to ovate as in Nannosquillidae , but unlike nannosquillids, the endopod is slender on pereiopod 3. Acaenosquilla , Heterosquillopsis and Kasim form a discrete group in the Tetrasquillidae , being unit- ed by the postanal spine and morphology of the pereiopodal endopods ( Ahyong & Harling 2000).

Figures

FIG. 2. — Kasim karubar n. sp., holotype (MNHN); A, anterior cephalon, dorsal; B, eye, right dorsal; C, raptorial claw, right lateral; D, TS5-8, right dorsal; E, AS5-6, telson and uropod, dorsal; F, telson, ventral; G, uropod, right ventral; H-J, pereiopods 1-3, right pos- terior; K, PLP1 endopod, right anterior; L, TS8 sternal keel, right lateral. Scale bar: A-J, 1.25 mm; K, L, 0.6 mm.