Taractichthys longipinnis

Carvalho-Filho, Alfredo, Marcovaldi, Guy, Sampaio, Cláudio L. S., Paiva, Isabel G. & Duarte, Luiz A. G., 2009, First report of rare pomfrets (Teleostei: Bramidae) from Brazilian waters, with a key to Western Atlantic species, Zootaxa 2290, pp. 1-26 : 18-20

Taractichthys longipinnis

Bigscale Pomfret, Lira-Galhudo. ( FIG. 18 A–D )

Diagnostic characters: Based on examined adult specimen (in brackets) and literature data ( Mead, 1972; Haedrich, 1986; Tomás et al., 1988; Smith, 1986; Thompson & Russell, 1996; Santos et al., 1997; Figueiredo et al., 2002; Thompson, 2003, 2008; McEachran & Fechhelm, 2005).

Body compressed, rather short and deep, the greatest depth 54–61% (56.3%) of standard length; dorsal profile of head strongly to moderate convex according to age; snout blunt; interorbital rounded; pre-caudal grooves well developed in adults; dorsal and anal fins stiff, covered with scales, and falcate; dorsal fin rays 33–38 (35); anal fin rays 27–30 (27); pectoral fin extends beyond anterior anal fin rays, with 20–22 (20) rays; horizontal series of scales 39–46 (41); gill rakers, 1–3 + 6–9 (1+8), not counting rudiments; scales on sides of body with a strong central spine, except in very large specimens as the one examined, aligned as in horizontal lines; scales of head and belly smooth; last scale on caudal peduncle larger than scales on caudal fin; caudal fin emarginated in young, forked to lunate in adults. Color varies from almost black to dark brown with bronze to silver sheen, belly somewhat lighter; all fins with same dark color as body and a silvery sheen; paired ones with large whitish areas; dorsal and anal fins often with whitish borders or distal spots, and the caudal with a conspicuous white posterior border.

The pre-caudal groove seems not to be developed in the young, at least to 50.0 mm SL, as commented on by Rob Robins after examining the UF juvenile specimen. Robins had used Thompson´s key (2003), on which Taratichthys and Taractes possess a well-developed transverse pre-caudal groove; observing that none was present on UF 168739, he concluded (erroneously as he said) that the fish was Eumegistus despite the high number of anal fin rays. Even after re-examining the specimen he had not see nothing as the illustrated groove ( Fig 3 of Thompson´s key, pg. 1470), leading him to the conclusion that perhaps the groove is absent in juveniles. Mead (1972) does not mention the presence or absence of it in juveniles.

Habitat, Depth, Temperature and Presumed Schooling Pattern: The bigscale pomfret is usually an offshore pelagic species occurring at least from 42 to about 200 m depth, and is apparently solitary, although also known to occasionally occur close to shore in small schools; there is evidence of its preference for waters of 10o C or colder ( Mead, 1972; Thompson & Russell, 1996; this work). Stomach contents of the collected specimen indicate that this pomfret feeds at or near the bottom, as the tropical pomfret does, since we found in its stomach an identifiable portion of an oplophorid bottom-dwelling shrimp species (M.S. Tavares, personal comment).

Diet: In the stomach of the large adult male we found a large, almost undigested ommastrephid squid (22 cm and 95 g) and part of a benthic oplopherid shrimp ( FIG. 11 )

Distribution: Eastern Atlantic: Iceland and Norway southwards to South Africa; Azores and Madeira Islands. Western Atlantic: Nova Scotia, Canada and northern Gulf of Mexico to Puerto Rico, Bermuda, northern South America to southeastern Brazil.

Proposed Brazilian name: “Lira-Galhudo” after its resemblance to the “Lira” ( Taractes rubescens ) and the high dorsal and anal fins (“Galhudo”).

Figures

FIGURE 3 The Tropical Pomfret becomes a daily catch off Bahia, Northeast Brazil.

FIGURE 11. Stomach contents of Taractichthys longipinnis caught off Bahia, Northeast Brazil: 1. Cephalopoda, Ommastrephidae;

FIGURE 18 A & B Taractichthys longipinnis, adult male, 472.4 mm SL, caught off Praia do Forte, Bahia, Northeast Brazil.

FIGURE 18 C & D Taractichthys longipinnis, UF 168739, young, 50.0 mm SL, from Bahamas.