Thursday, October 22, 2020

[Ichthyology • 2020] Rhynchobatus mononoke • A New Species of Wedgefish (Rhinopristiformes: Rhinidae) from Japan, with Comments on Rhynchobatus laevis (Bloch and Schneider 1801)


Rhynchobatus mononoke  
Koeda, Itou, Yamada & Motomura, 2020

モノノケトンガリサカタザメ ||  DOI: 10.1007/s10228-020-00777-z   

Abstract
Rhynchobatus mononoke sp. nov. (Rhinopristiformes: Rhinidae) is described from mature male and female specimens from southern Japan. A juvenile specimen, newly born from a captive individual collected from Kagoshima, is also referenced (non-type). The new species can be distinguished from congeners by a combination of its obtusely wedge-shaped snout, bluntly rounded dorsal fins, first dorsal fin originating about level with the pelvic-fin origin, and the outer fold on the spiracle posterior margin more pronounced than the inner fold. Distinctive coloration of the new species included a black blotch, followed by a single white spot (rarely absent) posterodorsally on the middle of the pectoral disc, and a large black blotch covering the anterior half of the undersurface of snout. Distinct white spots distally on the pectoral disc to the middorsal area were absent. Most previous records of species of Rhynchobatus in Japanese waters were reidentified as Rhynchobatus australiae, except for the records from the northern East China Sea. Rhynchobatus mononoke appears to be endemic to southern Japan.

Keywords: Rhynchobatus australiaeRhynchobatus djiddensisRhynchobatus laevis, Taxonomy, Endemic species, East China Sea, Rays


Fig. 1: Fresh holotype of Rhynchobatus mononoke sp. nov., off Satsumasendai, Kagoshima, Japan. KAUM–I. 80332, 1167 mm TL, male

Photographs of Rhynchobatus mononoke sp. nov. (specimens not retained). Kagoshima:
 ca. 2000 mm TL, captive bred individual.

Rhynchobatus mononoke sp. nov.

(New English name: Japanese Wedgefish; 
new standard Japanese name: Mononoke-tongarisakatazame
モノノケトンガリサカタザメ)

 Rhynchobatus djiddensis (not Forsskål 1775): Yamada et al. 2007: 94, pl. 5–5, (northern East China Sea); Kagoshima City Aquarium Foundation 2008: 32, fig. (Kagoshima, Japan, photograph of freshly captured individual); Kagoshima City Aquarium Foundation 2018: 37, fig. (Kagoshima, Japan, photograph of freshly captured individual).

Fresh paratype of Rhynchobatus mononoke sp. nov., off Nagasaki, Japan. KBF-I 1085, 1295 mm TL, male



Etymology. The specific name of the new species, mononoke - もののけ, means “specter” in Japanese, due to the ventral surface of specimens appearing like a traditional Japanese specter, wearing a triangular white hat (crown) on its forehead. The name is used as a noun in apposition.

 
Keita Koeda, Masahide Itou, Morihiko Yamada and Hiroyuki Motomura. 2020. Rhynchobatus mononoke, A New Species of Wedgefish (Rhinopristiformes: Rhinidae) from Japan, with Comments on Rhynchobatus laevis (Bloch and Schneider 1801). Ichthyological Research. DOI: 10.1007/s10228-020-00777-z  


「もののけ」が世に出ました

Ray at Kagoshima aquarium revealed as new species