[[Genus Torpedo Dumeril]]

Introduction

The genus Torpedo Dumeril, 1806 , consists of 21 valid species, two dubious species, and possibly three undescribed species (Compagno, 2005). Two subgenera are generally recognized, Torpedo Dumeril, 1806 and Tetronarce Gill, 1862 . The subgenus Tetronarce, with 10 valid species, can be distinguished from Torpedo by the absence of papillae around the spiracles and a uniformly drab, often dark brown to purplish-black dorsal coloration (Fraser-Brunner, 1949; Stehmann & Bürkel, 1984; Carvalho et al., 2002). In addition, the Tetronarce tend to occur primarily on continental slopes and around oceanic islands (Compagno, 2005). Those members of the subgenus Torpedo, by contrast, have papillae around the spiracles, are often ornately colored on their dorsal surface, and are usually found on continental shelves (Carvalho et al., 2002).

In the western North Pacific, only a single species, Torpedo tokionis (Tanaka, 1908), of the subgenus Tetronarce, is recognized (Jordan et al., 1913; Masuda et al., 1984). A second species, often referred to as T. nobiliana Bonaparte, 1835 ^ZBK, has on occasion been cited as occurring in Taiwanese waters (Chen & Chung, 1971; Chen & Joung, 1993; Chiu, 1994; Huang, 2001). However, the taxonomic distinction between these two species, or whether two species even occur in Taiwanese waters, has never been clearly documented. During a survey of the chondrichthyan fauna along the Taiwanese coast in 1988 and 2005, two species of the subgenus Tetronarce were collected by D.A. Ebert at a fish market in northeastern Taiwan. This material, now deposited in the ichthyological collection at the California Academy of Sciences (CAS), appears to represent two distinct Torpedo species, T. tokionis, and a new species described below.