Urocaris longicaudata Stimpson, 1860

Bruce, A. J., 2007, The resurrection of the pontoniine genus Urocaris Stimpson, 1860, (Crustacea: Decapoda: Palaemonidae), Zootaxa 1632 (1), pp. 61-67 : 63-65

Urocaris longicaudata Stimpson, 1860

( Figs. 1–3 )

Urocaris longicaudata Stimpson, 1860 , 39. — Rathbun, 1900: 155. — Rathbun, 1902: 126..

Periclimenes (Periclimenes) longicaudatus — Kemp, 1922: 135,.140, 141–142. — Holthuis, 1951: 23, 26–31, pl. 6a–m, pl. 8 m (full synonymy). — Williams, 1965: 42, fig. 35. – Nizinski, 2003: 104.

Periclimenes longicaudatus — Chace, 1972: 37. —Williams, 1984: 86. — Chace and Bruce, 1993: 58. — Li, 2000: 207– 218, fig. 268 (full synonymy). —De Grave, et al., 2007: (to be inserted.).

Material examined. (1) 1 spm, (without abdomen, dissected), stn. 127, #81, Barahona, Santa Domingo, 6 July 1933, AMNH #8711.

(2). 3 spms, juvenile, fragmentary, Santa Domingo, 5 August 1937, AMNH #8710.

(3). 2 spms (no second pereiopods), stn 196, Barahona, Santa Domingo, 5 August 1937, #98, AMNH #8712

(4). 13 spms (macerated and fragmentary), Anclote River Channel, Florida, 3.0– 5.4 m, 10 November 1941, AMNH 10087 .

(5). 1 (macerated), Anclote River Channel, Florida, 17 November 1941, AMNH 10106 .

(6). 3 spms, Isla de Cayo Cochinos Menor, Honduras, Thalassia bed, coll. D. Livingstone, OUMNH-ZC 2004-19-0006.

(7). 12 spms (two males dissected), stn. 57, Man-O-War Bay Tobago, approx, GPS 11°19.221' N 60° 33.100' W, 10 m, 18 September 2003, night light trap, over Caulerpa prolifera bed, coll. S. De Grave, OUMNH-ZC. 2004-22-034 .

Description: The specimens correspond closely to the detailed description and illustrations provided by Holthuis (1951). A detailed re-description is therefore unnecessary. Some points may be noted that were not previously mentioned.

Dissected specimen (sex?, CL 2.5 mm) with rostrum ( Fig. 2A ) with six dorsal teeth, with short interdental setae, first tooth situated over posterior orbital margin, ventral margin convex, with ventral carina obsolete, sparsely setose, with single very small acute tooth distally; carapace with epigastric spine, inferior orbital angle ( Fig. 2B , 3B ) strongly produced, rounded in lateral view, bilaterally compressed, antennal spine absent, hepatic spine well developed, at about 0.16 of CL, well below level of inferior orbital angle; antennule with small ventromedial tooth at about 0.3 of length of proximal segment, without proximo-dorsal protuberance, upper flagellum biramous with 8 proximal segments fused, shorter ramus with 2 free segments, about 16 groups of aesthetascs; basicerite similarly without proximo-dorsal protuberance; third thoracic sternite with feeble transverse carina, slightly thickened in midline, fourth thoracic sternite without median process, with two convex transverse ridges anteriorly, posterior ridge with pair of small submedian knobs, fifth with low transverse ridges posterior to second pereiopod coxae ( Fig. 3D ), posterior sternites unarmed; third pereiopod with slender dactylus ( Fig. 2C ) about 0.28 of propod length, unguis distinct, slender, about 5.0 times longer than basal width, 0.5 of corpus length, corpus about 3.0 times longer than basal width with well developed slender distal accessory tooth, about 0.65 of unguis length, ventral margin concave; propod sparsely setose, with pair of long distoventral spines, about 0.66 of dactylar corpus length, with three pairs of similar ventral spines.

Type: Syntype, BMNH Reg. No. 61.45 ( Evans, 1967) .

Type locality: “ Coast of Carolina ” .

Bathymetric range: Shallow littoral waters, to 11 m ( Holthuis, 1951).

Habitat: Among sea grasses ( De Grave et al, 2007).

Distribution: Between Cape Hatteras, North Carolina and São Paulo, Brazil ( Nizinski, 2003).

Remarks: Urocaris longicaudata is a moderately common shallow water inhabiting species and apparently free-living among sea grasses. The close morphological similarity to species of the aesopius group suggests that there may be a tenuous association with some coelenterates.

The mandibles of the dissected Tobago specimen are asymmetrical, the right incisor process has four stout teeth distally in an oblique row, with the largest tooth laterally, the next largest medially, with the central pair smaller, the medial margin of the process is quite unarmed. On the left the distal teeth are damaged and there may have been only two, or three: the medial margin of the process has four well developed slender acute denticles ( Fig. 3E ), larger distally than proximally.

Figures

FIGURE. 1. Urocaris longicaudata Stimpson, male, Honduras, OUMNH-ZC 2004-19-0006. Scale bar in millimeters.

FIGURE. 2. Urocaris longicaudata Stimpson, Santa Domingo, CL 2.0mm, AMNH #8711. A, carapace and rostrum. B, inferior orbital region, lateral. C, third pereiopod, dactyl and distal propod.

FIGURE. 3. Urocaris longicaudata Stimpson, male, Tobago, CL 1.9mm, OUMNH-ZC 2004-19-003. A, epistome. B, right inferior orbital region, lateral. C, same, dorsal. D, thoracic sternites. E, mandible, incisor process. F, left antennal peduncles and epistome, medial aspect.