Oratosquillina anomala

Oratosquilla anomala (Tweedie, 1935)

Squilla affinis var. intermedia Nobili, 1903:39 [part; not specimens from Nias=O. pentadactyla, new species; preoccupied by Squilla intermedia Bigelow, 1893].

Squilla oratoria var. perpensa.—Parisi, 1922:98 [part; specimen from Singapore only; not Squilla oratoria var. perpensa Kemp, 1911].

Chloridella oratoria.—Schmitt, 1931:147 [part; not Squilla oratoria de Haan, 1844].

Squilla anomala Tweedie, 1935:45.—Moosa, 1973:147.

MATERIAL.—Tsimei [Chi-Mei, Fukien Province; 24°34′N, 118°06′E], China; 25 Jun 1923: 3 , TL 83–87 mm (USNM 62188). Siglap [01°19′N, 103°56′E], Singapore, Malaysia; littoral; M.W.F. Tweedie, leg.; Jun 1934; holotype of Squilla anomala Tweedie: 1 , TL 85 mm (BMNH 1935.12.16.7). Data same; paratypes of Squilla anomala Tweedie: 1 , TL 69 mm; 1 , TL 82 mm (RMNH 248S). Singapore [01°17′N, 103°51′E], Malaysia; syntype of Squilla affinis var. intermedia Nobili: 1 , TL 66 mm (MCSN).

DESCRIPTION.—Size moderate, total length of adults less than 100 mm. Body appearing rough, surface pitted and irregular.

Eye (Figures 1b, 2b, 3a) very small to small, cornea bilobed, set obliquely on stalk. Eyes extending almost to end of first segment of antennular peduncle. Corneal indices 399–527.

Antennular peduncle shorter than carapace. Dorsal processes of antennular somite rounded, unarmed anteriorly.

Rostral plate (Figures 1a, 2a, 3a) broader than long, trapezoidal, apex truncate. Median carina absent.

Anterior width of carapace about half median length, less than half length carapace and rostral plate combined. Anterolateral spines (Figures 1a, 2a, 3a) strong, often extending beyond base of rostral plate. Median carina interrupted at base of anterior bifurcation, branches of bifurcation distinct. Intermediate carinae turning toward but not meeting laterals, not extending to anterior margin.

Dactylus of claw with 6 teeth, outer margin sinuate. Dorsal ridge of carpus (Figure 1c) undivided. Inferodistal angle of outer face of merus with sharp spine.

Exposed thoracic somites (Figures 1d, 2c, 3b) each with unarmed submedian and intermediate carinae, intermediates of fifth somite short, irregular. Lateral process of fifth somite bilobed, anterior lobe a slender spine, directed anterolaterally or almost anteriorly, posterior lobe slender, triangular, apex rounded, directed laterally. Lateral process of sixth somite bilobed, anterior lobe large but smaller than posterior, slender subrectangular, apex rounded or subtruncate, posterior lobe larger, triangular, apex acute but not sharp. Lateral process of seventh somite strongly bilobed, anterior lobe slender, more triangular than that of sixth somite, posterior lobe broader, posterior margin sinuous, apex acute but not sharp.

Submedian carinae slightly divergent on fifth abdominal somite. Abdominal carinae spined as follows: submedian 5–6, intermediae 4–6, lateral 3–6, marginal 1–5.

Telson flattened, slightly broader than long. Prelateral lobe longer than margin of lateral tooth. Denticles (Figures 1e) rounded or subquadrate, 3–4, 7–8, 1. Ventral surface of telson with postanal keel.

Uropod rather broad, proximal segment of exopod shorter than distal, with 8–9 movable spines on outer margin, distalmost not extending to midlength of distal segment. Lobe on outer margin of inner spine of basal prolongation (Figures 1f, 2d, 3d) small, narrower than adjacent spine, margin concave, apex rounded.

COLOR.—Faded in the material reported here. Tweedie (1935:48) noted: “Distal segment of the exopodite of the uropod similar to that of S. interrupta, but with a little more black suffusion; the inner half is never entirely blackish, as in S. oratoria inornata.”

MEASUREMENTS.—Males, TL 66–85 mm; females, TL 82–87 mm. Tweedie (1935) reported four males and five females ranging from 58 to 91 mm long. Other measurements of a female, TL 83 mm: CL 18.3, anterior width 9.3; cornea width 3.5; antennular peduncle length 15.6; rostral plate length 2.2, width 3.4; telson length 15.3, width 16.4.

DISTRIBUTION.—Known only from Tsimei, Fukien Province, China (Schmitt, 1931), and from Siglap, Singapore and Morib [02°45′N, 101°26′E], Selangor, Malaysia (Tweedie, 1935; Moosa, 1973); Singapore, Malaysia (Nobili, 1903). Apparently it occurs in shallow water; some of the types were taken in the littoral zone and Tweedie (1935) noted that some specimens came from fishermen's nets.