Paradynomene diablo, Mclay, Colin L. & Ng, Peter K. L., 2004

Mclay, Colin L. & Ng, Peter K. L., 2004, A taxonomic revision of the genus Paradynomene Sakai, 1963 (Crustacea: Decapoda: Brachyura: Dynomenidae), Zootaxa 657, pp. 1-24 : 14-16

Paradynomene diablo n. sp. ( Figs. 7 B, 9, 14D)

Paradynomene tuberculata— McLay, 1999: 543 (part). [Not Paradynomene tuberculata Sakai, 1963: 231 , fig 8.]

Material. Holotype male, 11.4 x 12.6 mm, station DW830, 361– 365 m, 23°20'S, 168°01'E, Norfolk Ridge, New Caledonia, coll. BATHUS 3, 29 Nov 1993 (MNHN­ B26607).

Description. Carapace sub­rectangular, width less than length, margins subparallel, surface very areolate, covered with pavement of small rounded closely packed granules. Carapace regions well marked by areas without granules. Frontal groove deeply marked, separating pair of epigastric tubercles, dividing to define mesogastric area that is without median tubercle. Protogastric tubercles well defined. Metagastric area scarcely inflated, weakly divided, without tubercles. Urogastric area well defined, without tubercles. Cardiac area swollen, shallowly divided into 2 weak tubercles. Intestinal tubercle absent. Branchial area dominated by 3 tubercles: 1 epibranchial tubercle, 1 similar mesobranchial tubercle, 1 smaller metabranchial tubercle. Total of 12 areolate tubercles on whole carapace: 6 on each side of mid­line, but no unpaired median tubercles. Lateral profile almost flat, largely because no tubercles are prominently elevated above carapace surface.

Rostrum tridentate, teeth small, median tooth deflexed, but visible dorsally. One similar, dorsally directed supraorbital tubercle behind rostrum, followed by much weaker tubercle, rest of orbital margin covered with small granules, strong suborbital tubercle visible dorsally. Orbits obliquely arranged, clearly exposed dorsally.

Anterolateral margin begins below level of postorbital corner, armed with 4 sub­equal teeth. First anterolateral tooth preceded by 2 or 3 small, closely spaced hepatic teeth that form anterior corner of carapace. Behind branchial groove are 2 well developed posterolateral teeth, last forming posterior corner of carapace.

Pereopods covered in small granules as carapace. Cheliped carpus with small tubercles on inner and outer proximal margins, three larger tubercles along outer distal margin. Propodus with 3 small tubercles along inner dorsal margin, 4 tubercles along outer dorsal margin. Fingers down­curved, small gap proximally, approximated for most of length, 3 or 4 almost obsolete teeth on fixed finger, 1 strong proximal tooth on moveable finger. At rest, fingers slot in beside bases of third maxillipeds that are covered with dense mass of fine setae. Margins of second to fourth pereopods tuberculate, fifth pereopod reduced, hidden under posterolateral carapace corner in dorsal view.

Surface of abdomen granulate, margins setose, abdomen only loosely held against sternum. No effective abdominal locking mechanism, uropod plates fill about half of lateral margin of sixth segment, adjacent to slightly elevated group of small granules on coxa of second pereopod restricting lateral movement of abdomen.

Etymology. The species name is derived from the Greek “diabolos” for devil, alluding to the appearance of the animal, especially in frontal view. The name is used as a noun in apposition.

Remarks. The differences between this species and its congeners are summarized in Table 1 .

The only known specimen was collected from a depth of 361– 365 m.

Figures

FIGURE 7. Dorsal views. A, Paradynomene demon n. sp., female holotype, 23.2 x 24.0 mm,, New Caledonia (MNHN­B 26602); B, P. d iab lo n. sp., holotype male, 11.4 x 12.6 mm, Norfolk Island (MNHN­B 26607).