Pseudopanopeus, Felder, 2020

Felder, Darryl L., 2020, A new crab of the genus Nanoplax from the Gulf of Mexico, and assignment of Micropanope pusilla to a new genus (Crustacea, Brachyura, Pseudorhombilidae), Zootaxa 4810 (3), pp. 531-545 : 540-541

Pseudopanopeus n. gen.

Type species. Micropanope pusilla A. Milne-Edwards, 1880 , by present designation.

Generic diagnosis. Carapace fronto-orbital width distinctly less than width of carapace (between lateral extremes of

anterolateral teeth), dorsal surface slightly convex, areolations evident, dorsal granulation coarsest across front; anterolateral margin with three prominent triangular anterolateral teeth (counting as one the outer orbital plus strongly coalesced obsolescent second tooth), positional fifth anterolateral tooth dimunitive to obsolescent; submarginal tubercle lacking from subhepatic region. Eyestalk short, not narrowed terminally. Chelipeds heterochelous in most specimens, dorsal surfaces smooth to granulate, unarmed; propodus upper surface elevated, depressed weakly (if at all) between low ridge of inner border and slightly developed outer border; carpus dorsal surface irregular, deeply depressed distolateral furrow, inner corner typically with at least one moderately enlarged acute tooth, distalmost usually largest if two or more present, major chela dactylus opposable margin with enlarged basal tooth. Ambulatory pereopod with merus superior margin nearly smooth, at most minutely denticulate. Male third through fifth pleonites fused, second pleonite spanning almost full width of sternum, eighth sternite narrowly exposed between lateral margin and condyle of fifth pereopod coxa, third pleonite spanning full width of sternum. Male first gonopod (G1) ( Fig. 4 A–C) subterminal spination including enlarged, proximally directed, enlarged spine (usually one, sometimes two), distal to which narrow shaft terminates in weakly curved, distally directed, microspinulous finger of similar length. Female gonopore (= vulva) an elongate, oblique oval, occupying anterior half of sixth sternite.

Etymology. The prefix “pseudo”, for false, is paired with the suffix “panopeus”, derived from the type genus of Panopeidae Ortmann, 1893 . As the gender is masculine, its combination with the type species name becomes Pseudopanopeus pusillus (A. Milne-Edwards, 1880) . While resembling panopeids in general habitus and long grouped among members of that family, this genus is one of several such that instead fall among Pseudorhombilidae in the phylogenetic analyses of Thoma et al. (2014).

Figures

FIGURE 4. Pseudopanopeus pusillus n. comb. A–E, male, cw 3.8 mm (ULLZ 8735 = USNM 1536350); F, female, cw 4.3 mm (ULLZ 12313 = USNM 1536351).A, left first gonopod, sternal surface; B, same, pleonal surface; C, right first gonopod, pleonal surface; D, left second gonopod, pleonal surface; E, flexed proximal pleon, posterior pereopod coxae, and exposed sternites, posteroventral surfaces; F, fifth and sixth sternites, pleon extended to show female gonopores, ventral. Scale bars = 0.5 mm.