Munidopsis centrina Alcock & Anderson, 1894

Ahyong, Shane T. & Poore, Gary C. B., 2004, Deep-water Galatheidae (Crustacea: Decapoda: Anomura) from southern and eastern Australia, Zootaxa 472 (1), pp. 1-76 : 47-50

Munidopsis centrina Alcock & Anderson, 1894 ( Fig. 9 )

Munidopsis centrina Alcock & Anderson, 1894: 170 [type locality: Bay of Bengal]; 1895, pl. 11: fig. 6.

Munidopsis (Orophorhynchus) centrina . — Alcock, 1901: 251, 270–271.

Material examined. AM P67045, 1 female (14.4 mm), Lord Howe Rise, Tasman Sea , 29°42.06’S, 159°48.31’E, 2450 m, pale grey ooze and pumice, beam trawl, FR0589­17, J. Lowry et al., 3 May 1989 .

Diagnosis. Carapace covered with long, coarse setae and short striae; with epigastric and protogastric spines; with dorsal hepatic spine (connected to antennal spine by low carina). Frontal margins oblique, relatively straight; antennal spine directed anteriorly and connected basally with dorsal hepatic spine by low carina. Lateral margins with 5 slender spines behind anterolateral spine. Rostrum spiniform, unarmed laterally, horizontal. Abdominal tergites unarmed. Sixth tergite with posterior margin not strongly produced. Telson composed of 10 plates. Eyestalk slightly movable, with medial, lateral and ventral spines, inner longest. Basal segment of antennal peduncle with lateral spine; second segment and third segments with lateral and medial spines. Epipods absent from pereopods. Cheliped short, stout, shorter than carapace; setose; pollex and dactylus distally ‘hollowed’on internal margin; pollex with denticulate carina on lower margin; carpus and merus strongly spinose. Walking legs setose and spinoseon extensor margin; dactylus with 8 or 9 stout triangular teeth on flexor margin.

Description. Carapace: Convex from side to side; covered with long, coarse setae and short striae; cervical groove faintly indicated; with paired epigastric spines, paired smaller lateral protogastric spines, and paired dorsal hepatic spines (connected to antennal spine by low carina). Frontal margins oblique, relatively straight; antennal spine directed anteriorly and connected basally with dorsal hepatic spine by low carina. Lateral margins with 5 slender spines behind anterolateral spine (3 spines in hepatic region and 2 in branchial region). Posterior margin unarmed. Rostrum spiniform, horizontal, unarmed laterally. Pterygostomian flap with striae; anterior margin produced into a small spine.

Sternum: Third sternite bilobed, separated by notch, about one­third width of sternite 4. Remaining sternites smooth, unarmed; ridges demarcating fourth to seventh sternites feebly granular.

Abdomen: Tergites with short, fine, scattered setae; unarmed. Second and third tergites unarmed; with elevated ridge followed by transverse groove. Sixth tergite with posterior margin not strongly produced. Telson composed of 10 plates. Uropodal endopod with unarmed lateral margins.

Eye: Slightly movable, non­setose; with medial, lateral and ventral spines, inner longest; cornea subglobular, slightly narrower than peduncle; without spine or tooth between eye and antennal peduncle.

Antennule: Basal segment with 3 slender distolateral and shorter distomesial spine.

Antenna: Lateral spine of basal peduncle segment not exceeding second segment; mesial margin produced to a blunt tooth. Second segment and third segments with lateral and medial spines.

Maxilliped 3: Dactylus, propodus and carpus unarmed. Merus with small distal extensor spine; with flexor margin with 3 spines in addition to several acute tubercles.

Epipods: Pereopods 1–4 without epipods.

Pereopod 1 (cheliped): Stout, shorter than carapace; setose. Propodus with palm about 1.5 times as long as high, without spines; dorsal margin of palm slightly longer than dactylus. Pollex and dactylus without gape; occlusal margins denticulate; distally ‘hollowed’on internal margin; pollex with denticulate carina on lower margin. Carpus and merus strongly spinose. Ischium with dorsal and ventral spines distally.

Pereopod 2–4: Setose and spinose. Pereopod 2 reaching anteriorly to base of pollex of pereopod 1. Merus squamous, setose; extensor margin with long spines; flexor margin with shorter spines. Carpus extensor margins with long spines. Propodus extensor margin spinose; distal flexor margin with paired movable spines. Dactylus with 8 or 9 stout triangular teeth on flexor margin.

Remarks. The present specimen agrees in most respects with published accounts and figures of Munidopsis centrina , known only from the holotype collected in the Bay of Bengal. It differs from Alcock’s account and figures of the holotype in lacking spines on the palm of the cheliped, the lateral spine of the basal antennal segment is consisderably shorter, being much shorter than instead of distinctly longer than the second segment, the first walking leg does not overreach the cheliped, a transverse row of two instead of four epigastric spines is present on the carapace, and the median group of protogastric carapace spines is absent. Unfortunately, neither Alcock & Anderson (1894) nor Alcock (1901) indicated the number of spines on the basal antennular segment. Although, the Australian specimen perhaps represents a distinct species, the aforementioned differences might also be size­related. The present specimen is about three­quarters of the size of the holotype. The present specimen represents only the second record of the species, so a description and illustrations are provided.

Distribution. The Bay of Bengal and now from eastern Australia; 2450–2719 m.

Figures

FIGURE 9. Munidopsis centrina Alcock & Anderson, 1894, 1 female (14.4 mm), AM P67045. A, dorsum. B, right lateral. C, right eye, lateral. D, left basal antennular segment, lateral. E, left basal antennular segment, ventral. F, left antennal peduncle, ventral. G, right third maxilliped, lateral. H, sternum. I, left cheliped. J, left cheliped, inner distal portion. K–M, left pereopods 2–4, dorsal. N, telson. Scale A, B, I, K–N = 3 mm, C–H, J = 1.5 mm.