Trachyscorpia Ginsburg

Hiroyuki Motomura, Peter R. Last & Gordon K. Yearsley, 2007, Two new species of the scorpionfish genus Trachyscorpia (Sebastidae: Sebastolobinae) from the southern Indo-West Pacific, with comments on the distribution of T. eschmeyeri., Zootaxa 1466, pp. 19-34 : 19-20

[[ Genus Trachyscorpia Ginsburg ]]

Species of the scorpionfish genus Trachyscorpia are deepwater, bottom dwelling, relatively large fishes, attaining at least 35 cm standard length. The genus was originally proposed for Scorpaena cristulata Goode & Bean, 1896 by Ginsburg (1953) who simultaneously included Scorpaena echinata Koehler, 1896 in the genus. Subsequently, Eschmeyer (1969) added Scorpaena capensis Gilchrist & von Bonde, 1924 to Trachyscorpia . Eschmeyer (1969) tentatively regarded T. cristulata and T. echinata as the subspecies, T. cristulata cristulata and T. c. echinata . He also separated the species of Trachyscorpia into two subgenera, Trachyscorpia (type species: T. cristulata ) and Mesoscorpia ( T. capensis ), the latter being his new subgenus.

The genus Trachyscorpia is characterized by the following combination of characters: occiput flat, lacking pit; first preopercular spine largest; head bones strongly ossified; suborbital ridge well developed, with usually 5 or more spines; palatine teeth present; dorsal-fin spines 12 or 13; vertebrae 25 or 26; pectoral-fin margin bilobed; lateral line complete, extending onto caudal-fin base; and scales on the body ctenoid (Eschmeyer, 1969; this study).

Trachyscorpia capensis was described as a new species of Scorpaena from the west coast of South Africa from three specimens (whereabouts of the syntypes currently unknown; e.g., Eschmeyer, 1998). Although the name T. capensis has been used in many publications since Eschmeyer (1969) (e.g., Eschmeyer, 1986; Ishida, 1990; Pakhorukov, 2001), T. capensis is permanently invalid because it was preoccupied by Scorpaena capensis Gmelin, 1789 , which is currently recognized as Sebastes capensis . Whitley (1970) proposed a replacement name, T. eschmeyeri , for Gilchrist and von Bonde’s Scorpaena capensis .

The species of Trachyscorpia from Australasian waters (mostly reported as T. capensis ) has been recognized as containing two sympatric morphotypes by several ichthyologists for a long time (e.g., Daley et al, 1997; A. Stewart and C. Paulin, pers. comm., 2004). Our further examinations of specimens from the region showed that the two morphotypes represent T. (M.) eschmeyeri and a distinct new species of Trachyscorpia (Mesoscorpia) . In addition, during examination of the Australasian specimens, another new species was found at the Australian National Fish Collection (CSIRO). This new species was collected from the South-West Indian Ridge, southwestern Indian Ocean (ca. 1,700 km south of the southern tip of Madagascar), and resembles the Australasian new species rather than T. (M.) eschmeyeri . The two new species are herein described in detail, along with a redefinition of the subgenus Mesoscorpia .