Munida collier, Ahyong, Shane T., 2007

Ahyong, Shane T., 2007, Decapod Crustacea collected by the NORFANZ Expedition: Galatheidae and Polychelidae, Zootaxa 1593, pp. 1-54 : 22-24

Munida collier sp. nov.

( Fig. 10 C, D, 12)

Type material. Holotype: NIWA 28068, male (17.8 mm), northern Norfolk Ridge, 26°25.94’S, 167°10.87’E, 750–774 m, TAN0308/043 #57, 18 May 2003. Paratypes: NMNZ, 1 female (16.4 mm), northern Norfolk Ridge, 26°25.94’S, 167°10.87’E, 750–774 m, TAN0308/043 #57, 18 May 2003; AM P73024, 1 male (19.6 mm), northern Norfolk Ridge, 26°25.94’S, 167°10.87’E, 750–774 m, TAN0308/043 #58, 18 May 2003; AM P73025, 1 male (20.1 mm), 1 ovigerous female (19.7 mm), northern Norfolk Ridge, 26°25.94’S, 167°10.87’E, 750–774 m, TAN0308/043 #56, 18 May 2003.

Diagnosis. Carapace margins with 5 spines posterior to cervical groove; transverse ridges well-spaced, with few, scattered, secondary striae; anterior branchial and postcervical spine absent. Rostrum spiniform. Sternite 4 anterior margin broadly and evenly convex. Abdominal tergite 2 with row of spines along anterior ridge; tergites 3 and 4 unarmed. Antennular basal segment terminal spines subequal. Antennal basal segment with strong mesial spine, apex not reaching beyond segment 2; segment 2 with distomesial spine reaching to midlength of segment 4. Maxilliped 3 merus extensor margin unarmed. Cheliped about 1.5 times carapace length; pollex ventral margin unarmed; merus distal spines with longest not reaching midlength of carpus. Pereopods 2 and 3 carpus extensor margin with 2 spines; dactylus with distalmost movable flexor spine proximal to dactylar apex by one-quarter length of flexor margin.

Description. Carapace: Transverse ridges well-spaced, generally entire, with very few secondary striae an anterior half, none on posterior half; gastric and cardiac regions with several short striae; hepatic region with scattered granules or short striae; cervical groove distinct; with pair of distinct epigastric spines behind supraocular spines, flanked mesially by 1 and laterally by 2 small spines; with 1 parahepatic spine; anterior branchial and postcervical spine absent. Frontal margins almost transverse; rostrum spiniform, horizontal, three times as long as supraocular spines and almost half remaining carapace length. Supraocular spines subparallel. Anterolateral spines situated at anterolateral angle, slightly divergent, not extending to base of sinus between rostrum and supraocular spine. Margins of carapace anterior to cervical groove with 2 spines (including anterolateral); with 5 spines posterior to cervical groove.

Sternum: Sternite 3 broadly subquadrate; anterior margin sinuous. Sternite 4 with 2 pairs of short striae, otherwise smooth; anterior margin broadly and evenly convex. Sternites 5–7 smooth. Ridges demarcating sternites smooth or slightly crenulate.

Abdomen: Tergite 2 with 8–11 spines along anterior ridge; with 1 transverse stria and 2 short arcuate striae laterally. Tergite 3 unarmed, with 1 medially interrupted transverse stria. Tergite 4 with 2 medially interrupted transverse striae. Tergite 5 with 1 medially interrupted transverse and 1 medially uninterrupted transverse stria.

Eye: Large, with maximum corneal diameter almost half basal distance between anterolateral spines; peduncle with few distal setae.

Antennule: Basal segment elongate, slightly overreaching cornea; terminal spines subequal; with 2 lateral spines, distal markedly longer than proximal.

Antenna: Basal segment with strong mesial spine, apex not reaching beyond segment 2. Segment 2 with small spine on mesial margin; distomesial spine reaching to midlength of segment 4, lateral reaching at least to midlength but not beyond distal three-quarters of segment 3. Segments 3 and 4 unarmed.

Maxilliped 3: Ischium with 2 small distal flexor spines. Merus shorter than ischium; flexor margin with strong distal and proximal spine; extensor margin unarmed.

Pereopod 1 (cheliped): About 1.5 times carapace length; with few rows of spines and few short squamae; margins with sparse plumose setae and scattered iridescent setae. Dactylus slightly longer than palm; unarmed dorsally except for small proximal spine; occlusal margin denticulate, without gape. Propodus palm 1.6 times as long as high, with dorsal, medial and ventral row of spines; pollex with 2 subdistal spines, ventral margin unarmed. Carpus 1.7 times as long as high, shorter than palm with dorsal, medial and ventral row of spines. Merus with strong distal and dorsal spines, longest not reaching midlength of carpus; surface otherwise unarmed except for row of 5 small lateral spines.

Pereopod 2: Merus with 11 or 12 extensor and 9 or 10 graded flexor spines. Carpus extensor margin with 2 spines, proximal margin minutely dentate; with distal flexor spine. Propodus 5.4 times as long as high; extensor margin unarmed; flexor margin with 8 small movable spines. Dactylus 0.7 propodus length; flexor margin with 8–10 movable spines, distalmost spine proximal to dactylar apex by one-quarter length of flexor margin.

Pereopod 3: Merus with 11 extensor and 6–8 flexor graded spines. Carpus extensor margin with 2 spines, proximal margin minutely dentate; with distal flexor spine. Propodus 5.9 times as long as high; extensor margin unarmed; flexor margin with 8 or 9 small movable spines. Dactylus 0.6 propodus length; flexor margin with 7 or 8 movable spines, distalmost spine proximal to dactylar apex by one-quarter length of flexor margin.

Pereopod 4: Merus with 10 or 11 extensor and 4 or 5 graded flexor spines. Carpus extensor margin with distal spine, proximal margin minutely dentate; with distal flexor spine. Propodus 4.8 times as long as high; extensor margin unarmed; flexor margin with 6 small movable spines. Dactylus 0.7 propodus length; flexor margin with 9 movable spines, distalmost spine inserting proximal to dactylar apex by one-quarter length of flexor margin.

Colour in life. Base colour translucent white. Carapace and abdomen diffuse pink with red striae; with or without whitish mottling. Chelipeds with red patch distally giving impression of diffuse red and white banding. Walking legs diffuse pink with white dactyli and proximal half of propodi.

Etymology. Named for my good friends, Peter and Melissa Collier ; used as a noun in apposition.

Remarks. Munida collier sp. nov. most closely resembles M. cerisa sp. nov., M. andamanica Alcock, 1894 , and M. rosula Macpherson, 1994 , sharing subequal terminal spines on the basal antennular segment, five spines on the branchial carapace margins, absence of anterior branchial and postcervical spines on the dorsal surface, and relatively short chelipeds (not exceeding twice carapace length) in which the longest distal merus spines do not overreach the midlength of the carpus. Munida collier differs from M. cerisa in having the ultimate flexor spine on the dactyli of the walking legs placed well proximal to the base of the unguis. From M. andamanica , M. collier is readily distinguished by colour-in-life (mottled red-pink carapace and white walking leg dactyli versus a uniform orange red carapace and red-tipped walking leg dactyli; compare Fig. 10 C–D with Baba in Baba et al. 1986: 168, top figure) and the secondary striation of the carapace: numerous in M. andamanica versus very few on the anterior half and none on the posterior half in M. collier . Munida collier is distinguished from M. rosula by the evenly curved rather than trianguloid anterior margin of sternite 4, absence of secondary striae on the posterior half of the carapace and presence of one (medially interrupted) transverse striae instead of two (one interrupted, one entire) on abdominal tergite 3, shorter mesial spine of antennal segment 1 that does not reach base of segment 3, and colour-in-life (chelipeds with extensive red patches versus some red at the articulations; compare Fig. 10 C–D with Macpherson 1994: fig. 82).

Distribution. Presently known only from the northern Norfolk Ridge; 750– 774 m.

Figures

FIGURE 10. A, Munida acacia sp. nov., female holotype, 20.6 mm (NMNZ) B, Munida cerisa sp. nov., male holotype, 16.2 mm, TAN 0308 / 29 (AM). C, Munida collier sp. nov., ovigerous female paratype, 19.7 mm, TAN 0308 / 043 (AM P 73025). D, Munida collier sp. nov., male paratype, 19.6 mm, TAN 0308 / 043 (AM P 73024). E, Munida endeavourae Ahyong & Poore, 2004, ovigerous female, 21.7 mm, TAN 0308 / 009 (NIWA 28077).