Nannosquilla taguensis

Nannosquilla taguensis

MATERIAL EXAMINED.—USNM 184176, holotype, 1, TL 16 mm; lagoon of Tague Bay, St. Croix, U.S. Virgin Islands, about 50 m from backreef in vertical burrow on side of Callianassa mound in fine coralline sand; depth, about 7 m; T. Suchanek, E. Bird, C. Shoemaker, M. Reaka, and S. Kudla, collectors; April 1979. USNM 184177, paratype, 1, TL 16.5 mm, data as for holotype. USNM 184178, paratype, 1, TL 17 mm; Central Tague Bay, St. Croix, U.S. Virgin Islands; 6 m; T. Suchanek and C. Shoemaker, collectors; 15 April 1979.

DESCRIPTION.—Eye small, not extending beyond antennular peduncle; cornea set obliquely on stalk, expanded laterally. Ocular scales fused basally; apices distinct, angular.

Antennular peduncle short, about half length of carapace; flagella short, upper with 8 articles, longer lower with 7 free articles, shorter with 3 free articles. Antennular processes visible as anteriorly directed spines projecting beyond sides of rostral plate.

Antennal peduncle short, not extending beyond eye; flagellum with 8 articles. Antennal scale very short, not reaching end of penultimate segment of peduncle.

Rostral plate subrectangular, wider than long, covering proximal half of ocular peduncles; medial area of dorsum slightly depressed; submedial areas slightly elevated, conforming to shape of ocular peduncles; lateral areas curving ventrally. Lateral margins of plate very slightly convex, subparallel proximally, slightly divergent distally. Anterolateral corners almost forming right angle, not acute. Anterolateral margins almost straight, very slightly concave, gently sloping to acute apex; apex barely produced beyond anterolateral corners.

Mandibular palp absent. Four epipods present.

Dactylus of raptorial claw with 7–10 teeth; proximal notch on outer margin of dactylus flanked by subacute proximal lobe and rounded distal lobe. Carpus with prominent, sharp, elevated spine at distal end of upper margin.

Basal segment of walking leg not produced as posteromesial lobe.

Sixth abdominal somite with posterolateral corners produced as long, acute spines.

Telson short, wider than long, very inflated; dorsum with submedian, shallow, wide sulci on posterior third, extending from area anterior of prominent, medial dorsal pit posteriorly to each side of median projection of false eave. Median projection of false eave broadly rounded, scarcely produced, flanked by very shallow, broadly rounded depressions; lateral margins of eave and posterolateral corners of telson broadly rounded; eave very inflated laterally, converging with true margin lateral to outer fixed teeth, almost obscuring latter. Marginal armature consisting of occasional single, short denticle on midline and, on either side, 7 or 8 submedian denticles, 1 movable submedian tooth originating immediately anterior to outermost submedian denticle, and 5 fixed teeth or denticles; small tubercle usually situated slightly above and between fixed teeth 2 and 3 and 3 and 4; tubercles sometimes absent or barely discernible.

Basal segment of uropod with ventral, proximal, elongate spine; dorsal spine of basal segment elongate, overreaching midpoint of endopod; inner spine of basal prolongation much longer than outer; outer spine very short, extending just beyond midpoint of inner margin of first segment of exopod. Proximal segment of exopod with 1 nonplumose, stiff seta on inner distal corner and graded series of 4 or 5 spatulate spines on outer distal margin.

Color in alcohol, white; numerous small, light brown, stellate chromatophores scattered over most of dorsum. One specimen (USNM 184177) with additional chromatophore pattern as follows: circular, dark spots at each corner of gastric region of carapace; exposed thoracic somites 5–8 with prominent submedian spots on anterior half of each somite, those on segments 6 and 7 largest; abdominal somites 1–5 with prominent submedian spots in middle of dorsum.

SIZE.—TL of holotype 16 mm; other measurements (in mm): CL 2.5; rostral plate length 0.8, width 1.2; telson length 1.3, width 2.2; antennal scale length 0.4.

DISTRIBUTION.—Known only from Tague Bay, St. Croix, U.S. Virgin Islands, in 6–7 m depths.

ETYMOLOGY.—The specific epithet is derived from the type-locality, Tague Bay, St. Croix.