Streptocephalus longimanus Bond, 1934

Materials investigated. Kovalam (13°04N, 80°18E), Chengleput (12°42N, 80°01E). Measurements. 9 males (15.3–16.9); 5 females (14.2–15.3). Accession numbers are DZ/NM/FS/141–142.

Description: Male­First antennae is slender, coiled at distal end and hidden under the compound eye (Fig. 4 A). Second antennae directed posteriomedially, proximal segment sub­cylindrical, distal segment slender. Antennal appendage long with five anterio­lateral sub­crenulate papillae proximal to the first curve, the first one being large compared to others (Fig. 4 B). Peduncle stout, S­curved, longer than second antennal proximal segment, and bears a lateral row of slender spines at the distal curve (Fig. 4 B, D). “Hand” elongate cheliform; thumb longer and equal to finger, bearing an arcuate spur, and no shoulder opposite the spur (Fig. 4 C). Finger is long, bifid with posterior ramus smooth and arcing anteriorly. Anterior ramus of finger with spines arranged as a series of shorter spines (Fig. 4 C, D). Thoracic and abdominal appendages are smooth. Penes have lateral linguiform projections at the base of proximal portion. Proximal non­retractile part of penes bears an anteriorly curved medial projection with no spines on the anterior surface (Fig. 4 G). Cercopods are lanceolate, setiferous to tip with fine setae and a groove in the middle on the entire length (Fig. 4 I).

Female. Second antennae is simple, flat and rectangular (Fig. 4 E, F). Brood pouch extends to the forth abdominal segment with a blue streak on its ventral surface (Fig. 4 H).

Cyst The cyst surface is covered with a series of pentagonal polygons. The ridges are raised, broad and with centered depressed fields (Figs. 4 J, K). The surface is covered with small pores both in ridges and depressed fields (Fig. 4 K).

Remarks. Streptocephalus longimanus Bond, 1934 can be separated from other species on the following characters: The second antennae of male has small spines on the posterior ramus, the thumb being equal to the finger; the penes has medial projections with a smooth surface; cercopods lanceolate with a groove. A bluish streak on the brood pouch is seen in the female. Cyst surface is covered with pentagonal polygons and has pores all over.