Nannosquilla yucatanica

Nannosquilla yucatanica

Nannosquilla antillensis.—Manning, 1969:72–74 [part, specimen from waters off Yucatan only].

MATERIAL EXAMINED.—USNM 111030; holotype, 1, TL 14.0 mm; northwestern Caribbean Sea, 2 mi WSW Cayo Norte, Banco Chinchorro [18°35′N, 87°22′W], Yucatan, Mexico, 5–6 m; coral reef; W.A. Starck, leg.; 23 Jun 1961.

DESCRIPTION.—Eye small, appearing stout, extending about to end of antennular peduncle. Cornea subglobular, set obliquely on stalk, expanded laterally, width 0.9 rostral plate length. Ocular scales with bases fused medially, apices distinct, flattened. Anterior margin of ophthalmic somite with obtuse point; ventral spine also present.

Antennular peduncle short, about half carapace length (curved ventrally in holotype, not visible in dorsal view). Flagella short, upper with 10–12 articles, longer lower with 10–11 free articles, shorter with 4 free articles. Antennular processes visible as short, anteriorly directed spines projecting beyond sides of rostral plate, apices not overreaching anterolateral corners of plate.

Antennal peduncle short, not extending beyond eye; flagellum with 9 articles. Antennal scale short, extending about to end of basal segment of peduncle.

Rostral plate rectangular, length 0.67 width, distinctly overreaching bases of eyestalks. Lateral margins of plate subparallel, slightly convex, at most slightly divergent anteriorly. Anterolateral corners broadly rounded. Anterior margins concave, sloping mesially to obtusely pointed apex, latter projecting well beyond anterolateral corners of plate.

Mandibular palp absent; 4 epipods present.

Dactylus of raptorial claw with 8 teeth (right claw missing from holotype); proximal notch on outer margin of dactylus flanked by subacute proximal lobe and broadly rounded distal lobe. Carpus lacking spine at distal end of upper margin.

Basal segment of walking leg lacking distal posteromesial lobe and lateral spine.

Sixth abdominal somite with posterolateral corners forming acute angles, not markedly produced posteroventrally.

Telson short, length 0.60 width, dorsum smooth. Median projection of false eave not prominent, wider than long, apex rounded. Submedian depressions of false eave shallow, shorter than lateral margin of telson, forming evenly concave curve toward broad submedian projections. Lateral margins of false eave forming about 45° angle with midline of telson. Marginal armature of telson on each side of midline consisting of 6 fixed submedian denticles, entire row forming inverted V in posterior view, with mesialmost denticles in line with remaining denticles on each side; 1 movable submedian tooth originating anterior to and slightly lateral of lateralmost submedian denticle; and 7 fixed lateral teeth and denticles. Of fixed lateral teeth, only lateralmost on false eave, remainder below eave; mesial 2 teeth on lower horizontal plane than others.

Basal segment of uropod with ventral, proximal tubercle; dorsal spine of basal segment slender, sharp, short (broken in Figure 8), not overreaching basal fourth of endopod. Outer spine of basal prolongation slightly but distinctly longer than inner (inner spine of right uropod broken in Figure 8). Proximal segment of exopod with 2–3 non-plumose stiff setae on inner distal corner and graded series of 5 spines on outer distal margin, distal 2 spatulate but slender and elongate, apices sharp.

Color completely faded.

SIZE.—Total length of holotype 14.0 mm; other measurements (in mm): carapace length 2.7; rostral plate length 0.8, width 1.2; telson length 1.2, width 2.0.

DISTRIBUTION.—Known only from the type-locality in the northwestern Caribbean Sea off Banco Chinchorro, Yucatan, Mexico; 5–6 m depth.

ETYMOLOGY.—The specific epithet is derived from the type-locality off the Yucatan Peninsula.