Extending geographical distribution range of Reef needlefish Strongylura incisa (Valenciennes, 1846) (Teleostei: Beloniformes: Belonidae) in the Eastern Indian Ocean with a key to the species of needlefish occurring in the area.

Abstract

Present study deals with new distributional records of Strongylura incisa (Belonidae) based on five specimens collected from the Andaman Islands and Tuticorin Coast (Tamil Nadu), India during 2016–17. Specimens were identified by absence of scales at bases of dorsal and anal fins, 19–20 dorsal fin rays, 21–23 anal fin rays, 102–113 predorsal scales, dorsal fin origin over 4–5 anal fin rays, prominent elongate spot on cheek between opercle and preopercle, and double lobe of gonad. Strongylura incisa can be distinguished from itsmost similar congener S. leiura based on number of predorsal scales (100–125 in S. incisa versus 130–180 in S. leiura), dorsal fin origin over anal fin rays (4–6 in S. incisa versus 7–10 in S. leiura), number of gonad lobes (2 in S. incisa versus 1 in S. leiura) and colour characteristics (prominent elongate spot on cheek between opercle and preopercle in S. incisa versus black bar on cheek between opercle and preopercle and anterior region of the body in S. leiura). Present study provides the first documented record of S. incisa from the Andaman and Nicobar Islands and East Coast of India with an updated key for Strongylura species. Further, it is an addition to the ichthyofaunal biodiversity of the Andaman and Nicobar Islands and East Coast of India.