Dasyatis acutirostra

Dasyatis acutirostra

Dasyatis acutirostra is a Stechrochenart and lives in the northwestern Pacific Ocean off the coast of southern Japan and the East China Sea. Like all stingrays she has a poisonous sting.

Features

Dasyatis acutirostra has a pectoral fin disk, which is in about as long as wide; the nose is in the form of an elongated triangle. The eyes are small, and behind them are slightly larger spray holes. There is a flap of skin with fringed hem at the back of Between the breathing holes. The upper jaw has 40 to 51, the lower jaw 39 and 49 teeth, which are grouped in a way quincunx pattern. Only in adult male specimens the teeth are spiky. The pelvic fins are broad and triangular. The tail is whip-like and longer than the disc. He wears one to two occupied barbed sting at the top. Along the middle of the back are 20 tubercles, above the spine again 16 The top is light brown and the underside white. The type specimen has a disk diameter of 72.5 cm, which is considerably larger than most comparison copies.

Way of life

The species inhabits coastal on and above the sea floor in the northwestern Pacific Ocean at depths 53-142 m. However, it is also reported sightings of larger animals to a depth of 420 meters and any sightings from the Gulf of Guayaquil Ecuador before. Dasyatis acutirostra is ovoviviparous with litters of two to six pups. About the other life practically nothing is known.

Systematics and history of research

Dasyatis acutirostra was not described until 1988. In the decades before the specimens of Dasyatis acutirostra the type Dasyatis had been assigned zugei. The mixing of the two species existed since the work of Jordan and Fowler Japanese elasmobranchs in the year 1903. 1988 published Kiyonori Nishida and Kazuhiro Nakaya a study on the species complex of Dasyatis zugei with the first description of Dasyatis acutirostra. The type specimen is an adult male of 72.5 cm wheel diameter, which had been caught in 1968 in the East China Sea and is kept at the University of Hokkaido. The specific epithet comes from the Latin words acutirostra acutus for " acute" and rostrum for " snout". The Japanese Vernakularname is Yajiri -ei.