Dark-Capped Harvestfish

description

Description. Morphometric data in Table 6, meristic data in Table 3. Counts D. III − IV. 39 − 47; A. II − III. 36 − 42; P. 20 − 22; vertebrae 11 − 12 + 17 − 19; gill rakers 2 − 6 + 13 − 16. Body compressed, short and very deep. Dorsal profile steep at snout, convex from eye to origin of dorsal fin, descending, convex along dorsal base to caudal peduncle. Ventral profile steep to convex from snout to origin of anal fin, with small concavity in front of anal fin, ascending, mildly convex along anal fin base to caudal peduncle. Head, dorsum and nape with vertical rows of branched, subdermal canals. Head deep, with very short snout and small mouth, barely reaching anterior border of eye, upper jaw fixed, very slender, with teeth long, conical or tricuspid in upper jaw, conical in lower jaw. Eye lateral and small, slightly closer to ventral margin than dorsal margin, post-orbital region larger than eye diameter. Opercle with prominent lobe on posterior margin, sometimes with concavity on posterodorsal margin. Scales cycloid, small, deciduous on flanks and dorsal and anal fin bases to nape, present also on belly, under eye (4 − 5 horizontal rows) and preopercle, absent from pectoral base

Review of the harvestfishes, genus Peprilus (Perciformes: Stromateidae), of the Atlantic coast of South America

diagnosis

Diagnosis. Peprilus xathurus differs from its congeners by the presence, mainly in fresh specimens, of a conspicuous dark spot over the eyes, from snout to nape (vs. inconspicuous or indistinct marking in all other representatives, Fig. 2 e, f), 11 − 12 pre-caudal vertebrae (vs. 13 or more, rarely 12 in all other representatives, except P. x an t hu r u s, Table 3), 28 − 29 vertebrae (vs. 30 or more vertebrae in P. medius, P. ovatus, P. simillimus, and P. snyderi, Table 3), body height 58.5 − 74.1 % SL (vs. 33.0 − 52 % SL in P. bu r t i, P. ovatus, P. simillimus, P. s n y d er i, and P. triacanthus), moderately falcate dorsal fin (vs. not falcate in P. triacanthus, or conspicuously falcate in P. p ar u Figs. 2, 4), anal fin falcate (vs. not falcate P. simillimus, P. ovatus, P. snyderi, P. bu r t i, and P. t r i a c an t hu s, Fig. 2), and no series of pores along the front half of the body under the dorsal fin (vs. 17 − 25 conspicuous pores in P. triacanthus). Peprulis xanthurus is further distinguished from sympatric P. crenulatus by specimens smaller than 110 mm SL, with orbital diameter 5.1 − 8.0 in anal-fin height (vs. 1.6 − 5.0 in P. xanthurus, Fig. 3 a), and 5.5 − 9.2 in the

Review of the harvestfishes, genus Peprilus (Perciformes: Stromateidae), of the Atlantic coast of South America

discussion

Remarks. Quoy & Gaimard (1825) described Seserinus xanthurus based on two specimens collected in Rio de Janeiro Bay, Brazil. The examination of the type specimens indicated that P. xanthurus is a valid species (Fig. 2 a), based on the relatively high anal fin to orbital diameter ratio, of 5.1 − 5.5 (vs. 3.2 − 5.0, rarely 5.1, in P. crenulatus). The type specimens also present a large dark spot from snout to nape (Fig. 2 a, e, f). The species status of P. xanthurus is further corroborated by the absence of P. crenulatus between Cape Frio, Rio de Janeiro and Paraná (23 o S to 25 o S), including the type locality of P. xanthurus (Fig. 8). Bernardes et al. (2005) identified a specimen of Peprilus xanthurus based on the presence of a long falcate anal fin, and the smaller eye in comparison with the post-orbital region, a conspicuous characteristic in the adult specimens. Figueiredo & Menezes (2000) and Fischer et al. (2011) also contain images of specimens with a long, falcate anal fin and small eyes, similar to Peprilus xanthurus.

Review of the harvestfishes, genus Peprilus (Perciformes: Stromateidae), of the Atlantic coast of South America

distribution

Distribution and habitat. Peprilus xanthurus occurs from Isla Margarita in Venezuela to Argentina (11 ° N to 38 ° S), inhabiting estuarine and coastal marine waters at depths of up to 95 m (Fig. 8 b). The species is very rare or absent on the northern and northeastern Brazilian coast (4 ° N to 13 ° S), but very common between the Brazilian state of Bahia-Espírito Santo and São Paulo (15 ° to 25 ° S), where it forms large schools and is caught in large quantities by trawlers, and abundant in local fish markets (A. Marceniuk, pers. obs.).

Review of the harvestfishes, genus Peprilus (Perciformes: Stromateidae), of the Atlantic coast of South America