Parapontocaris bengalensis ( Wood-Mason & Alcock 1891 )

Kuberan, G., Chakraborty, Rekha Devi, Purushothaman, P. & Maheswarudu, G., 2018, Two new records of deep sea shrimp under the genus Parapontocaris (Crustacea: Decapoda: Crangonidae) from the southwestern coast of India, Zootaxa 4450 (5), pp. 581-584 : 582-583

Parapontocaris bengalensis ( Wood-Mason & Alcock 1891)

(Fig. 2)

Crangon bengalensis Wood-Mason & Alcock, 1891: 360 (type-locality: Bay of Bengal).— Alcock & Anderson 1894: 152; 1895: pi. 9 figs 1-1a.

Pontophilus bengalensis — Ortmann 1895: 184.

Aegon ( Parapontocaris ) bengalense — ALCOCK, 1901: 122.— Kemp & Sewell 1912: 22.

Aegon bengalense — Kemp 1916: 379.

Aegon bengalense— DE MAN, 1920: 294.

Parapontocaris bengalensis— CHACE, 1984: 30.

Not Aegeon bengalense— CALMAN, 1939: 221 (? = P. levigata Chace, 1984 )

Parapontocaris bengalensis — Chan, 1996

Material examined: Southwestern Arabian Sea, Sakthikulangara, off Kollam, Kerala, India, 250–300 m depth, October 2013, 3 females ovigerous (CL 9–10 mm), 1 male (CL 9 mm), Marine Biodiversity Referral Museum at CMFRI: ED.2.6.1.8.

Characters of specimen from off Kerala Rostrum relatively long and elevated. Carapace about 1.7 times as long as wide; dorsal carina armed with 5 teeth, lateral carina I with 5 teeth, lateral carina II with 2 teeth and lateral carina III with only 1 tooth posterior to branchiostegal spine. Lateral ridges undeveloped on pleonal tergites III and IV. Posterior part of pleonal pleuron V without ridges. Pleomere II usually with 1 dorsal tooth and somite VI with 3 spines on dorsolateral ridge. Pereiopod 3 exceeding the pereiopod 1 by length of dactyl. Pereiopods 4 and 5 stout.

Coloration: Body pale reddish white. Rostrum and the carapace muddy brown. Eyes dark brown. Anterior part of the uropods reddish and posterior part reddish white. Eggs are opaque.

FIGURE 2.

Remarks: The present species P. bengalensis agree with the original description and keys by Alcock (1901) and ( Chan 1996). Previously ( Alcock 1901), this species was recorded in the Bay of Bengal at depths of 145—272 fathoms (265 m— 497.4 m) but in the present study, it is obtained at 250–300 m from the south west coast of India. Few specimens of P. bengalensis were noticed during October 2013 among the deep sea fishery landings. Morphologically P. bengalensis is most similar to P. levigata , the most distinguished character is explained in the remarks section of P. levigata .

Mitochondrial genes sequencing: COI (accession number: MH045675 ) and 16S (accession number: MH045676 ) sequences of P. bengalensis were submitted to GenBank. The sequence lengths are 634 and 481 bp for cytochrome c oxidase I (COI) and 16s rDNA genes, respectively. PCR purified products were sequenced by dideoxy chain termination method ( Sanger et al. 1977) using the ABI Prism 3770 automated sequencer from Scigenom, India. The level of interspecies divergence with COI & 16S sequence of the present specimen P. bengalensis was compared with other sequences retrieved from NCBI. Among COI, P. levigata and Parapontocaris sp ( KP759476 —9.1 % & KP759477 —8.8 %) showed high genetic difference while with 16S, P. levigata ( KP725615 ), Parapontocaris sp ( KP725616 ) and P. aspera ( KF 023107 ) the genetic difference was in the range of 2.1–6.2%.