Telatrygon acutirostra

The sharpnose stingray (Telatrygon acutirostra) is a poorly understood ray from the Dasyatidae family, inhabiting waters off southern Japan and the East China Sea. It has a rounded pectoral disc and a notably long, pointed snout, which led to it being frequently mistaken for the smaller pale-edged stingray (T. zugei). Key differences from T. zugei include larger eyes and the lack of a dorsal fin fold on the tail. Because its range appears limited, the IUCN lists this species as Vulnerable, as it is especially vulnerable to rising fishing pressure.

Taxonomy

Before its formal description, T. acutirostra was regularly confused with T. zugei, a mix-up that dates back at least to Jordan and Fowler’s 1903 review of Japanese sharks and rays. In 1988, Kiyonori Nishida and Kazuhiro Nakaya clarified the T. zugei species complex and formally described T. acutirostra in the Japanese Journal of Ichthyology. Its scientific name comes from Latin acuti (“sharp”) and rostra (“snout”). The type specimen is an adult male measuring 72.5 cm (28.5 in) across, caught by trawl in the East China Sea.

Distribution and habitat

This species is known from southern Japan and the East China Sea at depths of 53–142 m (174–466 ft), with a possible record from the Gulf of Guayaquil off Ecuador. Like most stingrays, it lives on the seafloor.

Description

The pectoral disc is roughly as wide as it is long, with rounded outer edges and concave leading margins that flow into a long, triangular snout. Its eyes are small, with larger spiracles behind them. A skin curtain between the nostrils has a fringed, straight rear edge. The mouth is slightly curved and lacks papillae on the floor.

It has 40–51 upper tooth rows and 39–49 lower rows, arranged in a quincunx pattern to form pavement-like surfaces. Adult males have pointed tooth cusps, unlike juveniles and females. The pelvic fins are wide and triangular.

The whip-like tail is longer than the disc and carries 1–2 stinging spines on top. A subtle dorsal keel and a low ventral fin fold sit behind the spine. A row of 30 tubercles runs along the back’s midline, with another row of 16 in front of the spine.

The tail behind the spine is covered in small denticles. Coloration is light brown above and white below. The largest known specimen has a disc width of 72.5 cm (28.5 in). It differs from T.