Upogebia inomissa A. B. Williams 1993

Upogebia inomissa

MATERIAL EXAMINED.—U.S.A.: Mississippi: USNM 251396,1 (holotype), Dog Keys Pass, W end of Horn Island, in shipworm tunnels in water logged wood, trawl, col. W.B. Sikora, 13 Jun 1991; USNM 251410, 1 (allotype), same; USNM 91255, 1 ovig. (paratype), Ocean Springs, col. J.F. Walker, Gulf Coast Research Lab., #10b, summer 1950. Florida: FDNR 7EJ83028, 1 (paratype, poor condition), Indian River Co., ∼25.9 km (14 nautical mi), E Vero Beach, 27°40′N, 80°06′W, 27 m, R/V Delaware II sta 025, 8-ft scallop tumbler dredge, W. Lyons, D. Camp et al., 21 Apr 1983; HBOM 89:243, 1 (paratype), Vero Beach, Indian River Co., 274 m (300 yd) E of sand point, inside dead Pleuroploca gigantea shell on coquina, 3 m (10 ft) depth, R.P.M., R.G.G., 26 Jul 1972; HBOM 89:2567, 1 juv., 1 (paratypes), Martin Co., Seminole Shores, worm reef, intertidal by hand, L.E.S., L.B., R.G.G., G.R.K, sta RGH-138-74,20 Jun 1974; HBOM 89:2650, 1 (paratype), St. Lucie Co., Jim Island, Ft. Pierce, in oyster clumps, intertidal, by hand, sta RGH-149-74, L.E.S., L.V.B., M.G.R., 17 Jul 1974; HBOM 89:3381, 1 (damaged paratype), St. Lucie Co., Jim Island, intertidal by hand, D. Putnam, P. Dudley, 7 Mar 1977; USNM 251411, 2 , 1 (paratypes). Sawyer Key, Florida Bay side, carbonate sand bar, 0.5–1.0 m, R. and S. Heard, J. Thomas, 10 Apr 1986; USNM 251439, 1 , St. Andrews Bay, from ship worm infested decomposing piece of wood at Panama City marina, 0.9 m (3 ft), water temp 23.9°C, 30 ppt, John M. Foster, 30 Oct 1992.

DIAGNOSIS.—Projections to either side of rostrum ending in acute spine. Postocular spine present. Abdominal sternites unarmed. T subrectangular. Carpus of cheliped with 1 strong and 1 short spine on mesiodistal margin. Merus of P2 bearing 1 proximal mesioventral spine and 2 subdistal dorsal spines; merus of P3 with 1 subdistal dorsal spine; merus of P4 usually spineless.

DESCRIPTION.—Rostrum triangular, short, straight to slightly downcurved in lateral view; tip exceeding slightly upturned eyestalks; dorsal pair of strong subapical spines followed on each side by 2–3 often remote spines; posteriorly divergent lateral ridge bearing crest of 12 or more spines, strongest on process lateral to rostrum and decreasing posteriorly. Shoulder lateral to cervical groove bearing 1–3 tubercles below intersection with thalassinidean line, and sometimes another above this juncture. Postocular spine present.

Abdominal sternites usually unarmed, but some adults show varying development of spines.

T subrectangular, prominent transverse proximal ridge confluent with inconspicuous lateral ridge at each side.

Eyestalk stout, deepest at about midlength in lateral view, concave dorsally, convex ventrally, more or less obliquely erect in repose; prominent terminal cornea narrower than diameter of stalk.

Al peduncle reaching to about length of terminal article of A2 peduncle, its proximal 2 articles together slightly longer than terminal article.

A2 peduncle with about its length extending beyond tip of rostrum; article 2 bearing subdistal ventral spine; scale moderate, oval.

Mxp3 bearing epipod.

Epistomial projection rather broad in lateral view, bearing 2 small unequal apical spines.

Chelipeds with coxa bearing slender spine on mesiodistal margin. Ventral margin of ischium bearing 1 spine. Merus with row of 4–7 strong spines on ventral margin; single subdistal dorsal spine reaching level of postocular spine. Carpus trigonal, shallow longitudinal groove laterally, strong spine at anterior ventrolateral corner preceded by 1 spine or row of sparse spines; remote mesiodorsal crest of 3–6 small spines behind prominent dorsal spine on anterior margin partly obscured by setae, proximal spine more erect than others, and 2–4 short stout spines obscured by setae on anterodorsal margin mesial to articulation with propodus; 1 strong spine near middle of anteromesial margin, smaller spine (sometimes much smaller and corneous tipped) dorsal to it, and strong slender spine at distoventral corner. Chl about 2.5 times chh; spineless dorsal ridge terminating anteriorly near stout subdistal spine mesial to it; mesiodorsal row of small spines (sometimes obsolescent) beginning with more or less erect spines proximally and becoming obsolescent at about – length; poorly developed distomarginal spine below lateral and mesial dactylar condyles, 1–3 remote smaller spines ventral to mesial condyle on distal margin; lower mesial surface spineless but low transversely arcuate ridge near proximomesial corner. Fixed finger shorter than dactyl and more slender, slightly downcurved in middle and tapering to slender tip, 4–6 teeth on proximal prehensile edge, not as well developed in female as in male. Dactyl longitudinally ridged and setose; that of female with corneous tip preceded on prehensile edge by either an unarmed interval or 1 or 2 rather stout low spines, then more or less rectangular tooth-like crest increasing proximally to its greatest height, and toothless section basally; curved extensor surface bearing about 3–4 small tubercles proximally; that of male with corneous tip preceded on prehensile edge by strong tooth, then finely multidentate prehensile crest bracketed on each end by larger tooth, and toothless section basally; concave mesial aspect in both sexes bearing 2 unequal rows of tubercles, most numerous in upper row.

P2 reaching about to distal of palm; carpus with acute distodorsal spine and tiny, nearly equal subdistal ventral spine; merus dorsally bearing slender distal spine and larger subdistal spine, and strong proximal mesioventral spine; coxa with proximal and distal raised areas mesially but no spines. Merus of P3 with slender distodorsal spine, sometimes a larger subdistal spine located closer to it than analog on leg 2, strong ventral spines tending to cluster near ischio-meral articulation, and cluster of smaller spines or spiniform granules proximolaterally; ischium unarmed and coxa with low spine lateral to gonopore. P4 with merus usually unarmed, occasionally a proximoventral spine, ischium unarmed.

U with acute spine on protopod above base of mesial ramus; lateral ramus with mesial rib bearing blunt spine proximally.

MEASUREMENTS (in mm).—Holotype , acl 6.4, cl 9.3, chl 5.4, chh 2.3; allotype , same, 7.9, 11.5, 6.3, 2.3.

COLOR.—Holotype (dorsal view): Branchiostegites, antennae, and displayed parts of folded legs milky white; broad dorsal tract running length of cephalothorax olive on setose field of anterior carapace and posterior cardiac region but bluish gray slate colored on gastric region; abdomen dorsally mottled bluish gray slate colored, but with middorsal row of darker polygonal designs, broad triangular patch on tergite 1, roughly trapezoidal patch on tergite 2, narrower but laterally disposed rectangular patch on tergites 3 and 4, and more elongate rectangular spot on tergite 5 and apparently on tergite 6, but full view of latter and tail fan as well as chelae not visible on photograph.

Allotype (oblique lateral view): General color pattern similar to that of male, but darker slate color on gastric region and pinkish salmon suffused with bluish gray in broad tract on cardiac region; abdomen similarly colored on tergites 1–3, but pleurae of these segments and segment 4 lighter with milky white margin, remainder of segments not visible; pleopods yellowish; oblique joint between ischium and merus of right cheliped slate blue. (From photograph taken by Walter B. Sikora shortly after formalin fixation.)

KNOWN RANGE.—Confined to material examined.

REMARKS.–Upogebia inomissa, new species, lacks sternal spines on the abdominal segments, so characteristic of U. omissa. Upogebia inomissa is similar to U. omissa in possessing 2 subdistal dorsal spines on the menus of P2, but unlike the latter almost always has only 1 such spine on the merus of P3, and it lacks spines on the merus of P4, whereas the merus of this leg in U. omissa almost always bears spines on the ventral margin. General spination of the carpus and palm of the cheliped of U. inomissa is much as in U. omissa, but the erect proximal spine in the mesiodorsal palmar row of U. inomissa is missing in U. omissa, and there are differences in the shape and spination of the fingers.

Upogebia inomissa is known only from the coast of Mississippi and southern peninsular Florida, but its geographic range may be broader than that now that possible confusion with U. affinis has been clarified.

ETYMOLOGY.—From the Latin prefix in- (not), plus omissa, the species that it resembles.