Lysmatella prima Borradaile, 1915 (Fig. 2A)

Lysmatella prima Borradaile, 1915, p. 209 & 1917, p. 403, pl. 58, fig. 7; Hayashi, 2007, p. 91, fig. 4a–c; Hippolysmata (Lysmatella) prima Kemp, 1916, p. 404; Holthuis, 1955, p. 115, fig. 80a.

Material examined. 1 ovigerous female (cl 6.1 mm), off Alleppey (9 o 25’72” N 76 o 12’ 77” E), southwest coast of India

from trawl, depth 30 m, 27 February 2018 (Fig.1).

Type locality Maldives (Borradaile, 1915).

Diagnosis of the specimen: Rostrum armed with 9 dorsal and 7 ventral teeth, subequal. Epigastric tooth situated at 0.25 of post orbital carapace length. Three dorsal teeth situated behind the orbital notch (Fig. 2B), remaining anterior to the post orbital margin. Post orbital, antennal and pterygostomial spines well developed (Fig. 2C). Terminal segment of third maxilliped with strong spines (Fig.2D). Abdomen 1.5 times longer than carapace. Sixth abdominal segment longer than deep, about 1.4 times length of fifth. Second pair of pereiopod slender with 18–19 articulations on the carpus (Fig. 2E). Telson about 1.2 times longer than the last abdominal segment, with two pairs of long erect dorsal spines (Figs. 2 G– H), located 1/5 and 3/5 length of telson respectively. Telson as long as uropods, posterior margin with long, strong setae. Eyes large, cornea darkly pigmented (Fig. 2A). Eggs oval 2.2–2.3 mm x 1.7–1.8 mm, with well-formed eyespots (Fig. 2I). Total length 22.36 mm (approx.). Carapace length 6.1 mm, Rostrum 6.7 mm.

Distribution: Horizontal distribution: Indo-west Pacific distribution, recorded from Haddumati, Mulaku, and South Nilandu Atolls, Maldives (Borradaile, 1915), Port Blair, Andaman Islands (Kemp, 1916), Singapore (Johnson, 1961), Australia (Hayashi, 2007), Philippines, Indonesia (Chace, 1997), Japan (Minemizu, 2000) and now from Arabian Sea.

Bathymetric distribution: 8 fathoms (Kemp, 1916), 59 m (Holthuis, 1955), 62 m (Chace, 1997), 30 m (present study).

Coloration in life: The specimen had bright reddish brown longitudinal stripes on carapace and abdomen, antennule, antenna, pereiopod and pleopods yellow.

Habitat: Present specimen obtained from 30 m depth along with coral polyp.

Remarks: Morphologically the specimen agrees with the original description (Kemp, 1916) however with certain variations. Number of dorsal and ventral rostral teeth more or less conforms to Borradaile (1917) and differs from Kemp (1916) and Australian specimens (Hayashi, 2007). Second pereiopod has 18–19 articulations which is less than that given by Kemp (1916), Borradaile (1917) and Chace (1997). According to Borradaile, (1917), the dactylus of the pereiopods are provided besides the end-claw with three movable spines on the lower side and of these the third is larger than the end-claw. In the material examined herein the first pereiopod has four movable spines with the fourth larger than the end claw (Fig. 2F). In the individuals examined by Chace (1997), chelae of first pereiopod is 11/3 times as long as carpus but herein the present material chelae is as long as carpus. Our specimen is comparatively larger compared to Borradaile (1917) 19 mm but comparable to 23 mm recorded by Kemp (1916) from Port Blair. L. prima is geographically widespread including the Andaman Sea, Bay of Bengal but never before documented from the Arabian Sea.