Torpedo adenensis, a New Species of Electric Ray from the Gulf of Aden, with Comments on Nominal Species of Torpedo from the Western Indian Ocean, Arabian Sea, and Adjacent Areas (Chondrichthyes: Torpediniformes: Torpedinidae)

Abstract

A new species of electric ray of the genus Torpedo is described from the eastern Gulf of Aden, northwestern Indian Ocean. Torpedo adenensis, n. sp., is placed in the subgenus Torpedo due to the presence of small, knoblike papillae around its spiracles. It is distinguished from all other congeners by its unique dorsal coloration, consisting of a uniform reddish-, rusty-, or orange-brown without any distinctive spots, blotches, or reticulations. A unique combination of characters further distinguishes T. adenensis, including the proximity of the spiracles and eyes, the distance between the second dorsal and caudal fin, which is greater than the distance between the first and second dorsal fins, and the presence of an integumental flap in the clasper glans region. Torpedo adenensis is sexually mature when between 280 and 395 mm in total length, is known from specimens of both sexes, including adults and subadults, and is the only species of Torpedo unequivocally reported from the Gulf of Aden to date.

Phylogenetic significance of clasper morphology of electric rays (Chondrichthyes: Batoidea: Torpediniformes)

“…Externally, the examined claspers of members of the family Torpedinidae are distinguished from others electric rays by presenting an integumental flap (if). The structure has also been reported in other torpedinids ( Torpedo and Tetronarce ) by other authors (e.g., de Carvalho, Stehmann, & Manilo, 2002; Ebert, Hass, & de Carvalho, 2015; Haas & Ebert, 2006) and it is absent in other electric rays such as in the narkid Electrolux addisoni (Compagno & Heemstra, 2007 and de Carvalho, pers. obs.).…”

New insights into the identities of the elasmobranch fauna of Sri Lanka

“…Two of these specimens have been deposited in the BRT Ichthyology Collection (SL-28, BRT-I 0009; SL-56, BRT-I 0014). This species bears a conspicuous pale reticulated pattern, apparently formed by fused spots, on a dark brown dorsal surface and thus most closely resemble Torpedo sinuspersici von Olfers as characterized by de Carvalho et al (2002). However, the number of pale spots composing the reticulations, and thus the size of the reticulations, is smaller than seen in T. sinuspersici.…”

An annotated checklist of the chondrichthyans of Taiwan

“…11, fig. 1 Remarks: The separation of Tetronarce formosa from T. tokionis (Tanaka, 1908) and T. nobiliana (Bonaparte, 1835), the latter speciesreported from Taiwan prior to Haas & Ebert (2006), is not straight forward, a circumstance widespread in the systematics of Tetronarce (Carvalho et al, 2002). Tetronarce formosa resembles T. tokionis most, not being as dark or purplish-black dorsally as T. nobiliana, but this character is highly variable, as are proportional measurements that depend on the state of preservation of material, which is frequently poor.…”