Harttia merevari, R & Machado-Allison & Chernoff & Willink & Petry, 2005

R, Francisco Provenzano, Machado-Allison, Antonio, Chernoff, Barry, Willink, Phil & Petry, Paulo, 2005, Harttia merevari, a new species of catfish (Siluriformes: Loricariidae) from Venezuela, Neotropical Ichthyology 3 (4), pp. 519-524 : 520-523

Harttia merevari , new species

Figs.1-2

Holotype. MBUCV-V-26578, 99.4 mm SL. Venezuela, Bolívar State, Caura River at the top of Salto Pará waterfalls, among rocks on the eastern side of the river, 17 Sep 1993, C. Silvera, F. Provenzano, A. Machado-Allison, B. Chernoff, H. López- Rojas & A. Rojas.

Paratypes. MBUCV-V-30850, 4, (68.4-88.8 mm SL) and FMNH 116484 , 3 , (66.5-81.2 mm SL) . Venezuela, State Bolívar, Caura River, near the top of Salto Pará waterfalls, among rocks on the eastern side of the river, 30 Nov 2000, A. Machado-Allison, F. Provenzano, B. Chernoff, & A. Rojas .

Diagnosis. Harttia merevari is distinguished from all congeners by the following combination of external characters: abdomen naked; two or three preanal plates, triangular, rectangular or square in shape; smaller plates, variable in number, arrangement and shape, present anterior to preanal plates, particularly in smaller specimens; broad triangular plate present anterior to each branchial opening; seven lateral (thoracic) plates between the pectoral and pelvic fins; maxillary barbels short, united to oral disk with fleshy flap; dorsal surface of head and anterior portion of body light or dark yellow with numerous black spots; dorsal and posterior portion of body light or dark yellow with five black transverse bands; anterior two bands with a diffused central portion; and caudal fin forked

Description. Morphometric data presented in Table 2. Head and body depressed. In dorsal view, body slender ( Fig.1); cleithral width 20.39% SL (4.91 times SL). Snout rounded, contour oval in dorsal view. Supraorbital border raised. Interorbital area and supraoccipital flat. Lip margins undulated slightly. Lip surfaces covered with papillae, except small naked region near dentary. Teeth numerous, 50 or more in each dentary. Teeth very thin and elongate, forked and asymmetric with inner lobe larger and rounded; apex arched toward interior of mouth and yellowish, while rest of tooth whitish. Interior of mouth with only one small elongated papilla on roof of mouth, located midline between premaxillaries and oral valve. Very small maxillary barbel joined to inferior lip by thin fleshy flap. Triangular plate anterior to each branchial opening, ornamented with small odontodes. Abdomen naked. Preanal region with two or three well developed plates ( Fig. 2). Small specimens with two rectangular or square preanal plates preceded by one to seven small, irregularly shaped plates, in irregular arrangement. Holotype with three well defined preanal plates: middle triangular plate with apex directed to anus; sided by two large and rectangular plates. Each lateral preanal plate preceded by single, small, square plate ( Fig. 2) Six or seven plates between pectoral and pelvic fins. 30 or 31 lateral plates. Anterior lateral plates carinate, forming double keel until plate 17 or 18, after which plates unite to form single keel to base of the caudal fin. Dorsal fin I,7 Pectoral fin I,6 Pelvic fin I,5. Anal fin I,5 Caudal fin i,12,i.

Coloration. Dorsal region of head and anterior part of body light or dark yellow with many black spots. Posterior region of body light or dark yellow with five transverse black bands; first two bands with diffused central portion ( Fig. 1). Ventral region of head and body whitish. Dorsal, pectoral and pelvic fins with rectangular or square black blotches on rays; interradial membranes hyaline. Dorsal, pectoral and pelvic fin spines with four, five and four black blotches, respectively. Anal fin uniform whitish or yellow. Caudal fin with four black blotches on rays, and two transverse black bands. Anterior transverse band wide and well defined near base of middle rays; posterior band thin and weakly defined. Distal border of caudal fin hyaline

Habitat. Harttia merevari was captured very close to the top of Salto Pará ( Fig. 3), a 50 m fall that separates the Caura River into upper and lower faunal sections ( Chernoff et al., 2003). The specimens were captured on and among relatively large rocks with flat surfaces, very near shore. The water was transparent with flow from fast to very fast. Podostemataceas were growing on the rocks. The depth at the colleting site was 1.5 meters on average.

Etymology. The species-group name, merevari , is the Ye-kuana name for the Caura River, and is treated here as a noun in apposition.

Comparisons. The largest known specimen of H. merevari is 99.4 mm SL and this specimen as well as all other paratypes, which are smaller, have a naked abdomen. There is no evidence of plate development over the abdomen. The lack of abdominal plates places H. merevari into a group of species of Harttia with naked abdomens: H. carvalhoi , H. depressa , H. garavelloi , H. gracilis , H. guianensis , H. kronei , H. leiopleura , H. loricariformis , H. novalimensis , and H. torrenticola . Harttia uatumensis probably should be considered a member of this group because this species possesses a single small patch of plates over the abdomen. Harttia carvalhoi , H. garavelloi , H. kronei , H. leiopleura , and H. novalimensis differ from H. merevari because each lacks the preanal plates present in the new species ( Oyakawa, 1993; Langeani et al., 2001). In juveniles of H. torrenticola preanal plates are absent, adults have preanal plates but they are circular in shape, sparse, and reduced in number from 2 to 4 ( Oyakawa, 1993). Harttia gracilis and H. loricariformis have two trapezoidal preanal plates, and 3 or 4 small plates anterior to those ( Steindachner, 1877; Oyakawa, 1993). Additionally, H. leiopleura and H. novalimensis lack a bony plate in front of the gill opening; H. garavelloi does not have a maxillary barbel; and H. leiopleura does not have lateral plates between the pectoral and pelvic fins ( Oyakawa, 1993). The external morphology of H. merevari resembles H. punctata but differs by the type of abdominal covering (naked vs. partially covered, respectively) and other morphometric and meristic measurements. Harttia depressa , H. guianensis , and H. uatumensis have naked abdomens as in H. merevari but differ in color pattern, body shape, and morphometric or meristic measurements.

Geographic Distribution. Harttia species are primarily distributed in the Amazon River basin and southeastern Brazil, but a few including the new species are found in the Guianas and the Orinoco River basin ( Table 1). Harttia merevari extends the northwestern distribution of the genus to the northwestern slope of the Guyana shield draining into the Orinoco basin, being the first species to be recorded in this area ( Fig. 3). If we consider the genus Cteniloricaria as a synonym of Harttia as proposed by Rapp Py-Daniel & Oliveira (2001), the number of species assigned to Harttia reaches 22 species. Along the Guyana Shield, Harttia species are found in rivers in Suriname ( Suriname River), French Guiana (Approuague and Sinnamary rivers) and Venezuela (Caura River and Cuyuni - Essequibo River drainage) draining the northern slope of the shield, and the Trombetas and Uatumã watersheds draining the southern slope of the Guyana Shield in Brazil ( Boeseman, 1971; Machado-Allison et al., 2000; Rapp Py- Daniel & Oliveira, 2001) Further south, species have been reported from the Tapajós and Tocantins River basins on the northern slope of the Brazilian Shield (Rapp Py-Daniel & Oliveira, 2001), São Francisco basin, upper Paraná and coastal drainages of southeastern Brazil ( Steindachner, 1877; A. Miranda Ribeiro, 1908; P. Miranda Ribeiro, 1939; Oyakawa, 1993; Langeani et al., 2001) There is no particular distributional pattern among the species with or without naked abdomens; representatives of both groups are found along the Guyana shield and the southeastern region of Brazil.