Enoplometopus crosnieri Chan & Yu, 1998

Poupin, Joseph, 2003, Reef lobsters Enoplometopus A. Milne Edwards, 1862 from French Polynesia, with a brief revision of the genus (Crustacea, Decapoda, Enoplometopidae), Zoosystema 25 (4), pp. 643-664 : 645-646

Enoplometopus crosnieri Chan & Yu, 1998 ( Figs 2 ; 3 )

Enoplometopus crosnieri Chan & Yu, 1998: 184 (type locality: Keelung, northern Taiwan).

Enoplometopus sp. nov. – Poupin et al. 1990: 16 (French Polynesia). — Poupin 1996a: 12 (Hiva Oa, Ua Pou; 100-120 m); 1996b: 8; 1998: 37 (checklists).

MATERIAL EXAMINED. — French Polynesia. Marquesas Islands, Ua Pou, Frv Marara , stn 288, 9°20.5’S, 140°02.0’W, trap 120 m, 28.VIII.1990, 1 ♂ cl 45 mm, bl 131 mm, 4 ♀♀ ovig. cl 35-43 mm, bl 106- 128 mm (MNHN As 570), 2 ♂♂ cl 40-47 mm, bl 120-142 mm, 2 ♀♀ ovig. cl 41-46 mm, bl 124- 134 mm (MNHN As 571). — Hiva Oa, MUSORSTOM 9, Frv Alis, stn CP 1227, 9°44.2’S, 138°52.5’W, 84-85 m, 30.VIII.1997, remains of chelae only (MNHN As 616). — Hiva Oa, Frv Marara , stn 193, 9°49.7’S, 139°09.1’W, 9.IX.1989, trap 100 m, 1 ♂ cl 39 mm, bl 116 mm (MNHN As 560).

Australia. Timor Sea, near Darwin, coll. NT Fisheries, 10°18’S, 129°52’E, trap 91.5 m, 10.X.1992, 1 ♂ cl 40 mm, bl 118 mm ( NTM Cr009567).

DISTRIBUTION. — West and central Pacific: Taiwan (Keelung), Australia (Timor sea), French Polynesia (Marquesas Islands: Hiva Oa, Ua Pou). Depths: 84- 120 m. On hard bottoms.

SHORT DESCRIPTION

Lateral margin of rostrum with two spines. Carapace armed with six median, one postcervical, one intermediate, one supraocular, and two lateral spines ( Fig. 3A ). Chela broad and compressed 3.0-3.7 times as long as wide (average 3.3), furnished with long setae on margins. Upper and lower faces with several rows of tubercles. Outer margin of palm and fixed finger with 16- 20 spines, upwardly directed. Inner margin of palm with five or six main spines and secondary smaller spines at bases. Dactyl 0.5 times as long as chela, with inwardly curved tips; cutting edge with five or eight larger teeth, forwardly directed, and smaller denticulations in between; outer margin with seven to nine spines ( Fig. 3C ).

Second pereopod circular in cross section, with small distal pincer. Merus and carpus with or without distoventral spine. Distal margin of propodus with a ventral process bearing a row of small corneous spines on its upper margin and two mobile spines, distally ( Fig. 3D ). Dactyl 0.3 times as long as propodus, with strong distal claw; outer face with two spines; inner face with one spine; lower margin with row of tiny spines. Third and fourth pereopods shorter than P2, with terminal pincers reduced. Fifth pereopod the shortest, without terminal pincer.

Pleura of abdominal somites II-IV and VI bluntly pointed; pleuron of somite V rounded ( Fig. 3B ). Male first pleopod subrectangular, fitted in Vshaped hollow formed by thoracic sternite VII; distal margin straight, without distal indentation ( Fig. 3F ). Telson with one lateral spine and three distolateral spines, inner pair longest ( Fig. 3E ).

Coloration ( Fig. 2 )

Ground color of body orange red. Lateral face of carapace with large white circle in distal half, and two white oblique lines, posteriorly. Ambulatory legs orange with narrow white bands on basis, ischia and meri, uniformly yellow orange on carpi, propodi and dactyls. Abdomen with red blotches and white spots as illustrated in Figure 2.

REMARKS

Although there are usually six median spines in Enoplometopus crosnieri , it has been observed that the anteriormost spine was reduced to a granule on five specimens examined out of 11 (see Fig. 3A ). The posteriormost median spine is situated on the cervical groove, as also observed in E. callistus . To avoid misidentification when using a key, it must not be counted as a “postcervical” spine (see Remarks under E. callistus ). The tubercles situated on the upper face of the palm of the chela can be greatly reduced in the smallest specimens (cl <40 mm), the aspect of the upper face of chela being then almost smooth whereas it is typically tuberculate in larger specimens.

Within the six Enoplometopus species that have a large chela with tubercles on the upper face, and abdominal pleura II-V rounded or bluntly pointed ( E. chacei , E. crosnieri , E. daumi , E. debelius , E. occidentalis , E. pictus ), only E. crosnieri possesses a large white circle on the lateral face of the carapace and it is therefore easy to recognize in living specimens. It can be morphologically recognized by the armament of the carapace, with two lateral, one intermediate, and six median spines, whereas the five other species have three lateral, two intermediate, and four or five median spines. Enoplometopus crosnieri also differs from E. chacei , E. daumi , E. debelius , and E. occidentalis by the aspect of the outer margin of dactyl of chela, which has seven to nine spines along its whole length, whereas there are only two or three distal spines in the four other species.

Figures

FIG. 2. — Enoplometopus crosnieri Chan & Yu, 1998, ovig. ♀ cl 41 mm, Marquesas Islands (MNHN As 571); A, lateral view; B, dorsal view.

FIG. 3. — Enoplometopus crosnieri Chan & Yu, 1998, ovig. ♀ cl 41 mm, Marquesas Islands (MNHN As 571); A, carapace, dorsal view; B, abdomen, lateral view; C, left chela, dorsal view; D, dactyl and distal part of propodus of left second pereopod, outer view; E, posterior margin of tergite 6 and telson, dorsal view, ♂ cl 47 mm, Marquesas Islands (MNHN As 571), F, right first pleopod, outer view (setae omitted). Scale bars: 5 mm.