Leporinus tepui, Leporinus & Characiformes & Anostomidae & Birindelli & Britski & Provenzano, 2019

Birindelli, José L. O., Britski, Heraldo A. & Provenzano, Francisco, 2019, New species of Leporinus (Characiformes: Anostomidae) from the highlands of the Guiana Shield in Venezuela, Neotropical Ichthyology 17 (2), pp. 1-6 : 2-4

Leporinus tepui , new species

urn:lsid:zoobank.org:act:BAA0E2DB-3FEB-4421-BB8C-0E78A7FDF81F

Fig. 1

Leporinus arcus .—Chernoff, Machado-Allison, Riseng, Mointambault, 2003: 70 (upper Caura River, AquaRAP report).

Holotype. FMNH 45711, 143.7 mm SL, Venezuela, Bolívar, río Orinoco basin, Chimantá-tepuí , c. 5°18’N 62°10’W, 27 Mar 1953, J. Steyermark.

Paratypes. All from Venezuela, Bolívar, río Orinoco basin . MZUEL 21000 , 1 , 42.8 mm SL ; MZUSP 124855 , 1 , 41.3 mm SL . FMNH 109898 , 2 , 41.0- 69.6 mm SL, Raudal (rapids) in río Erebato and mouth of creek across river, río Caura drainage, 5°52’44”N 64°29’34”W, 27 Nov 2000, F. Provenzano, B. Chernoff, A. Rojas, A. Machado-Allison . FMNH 109899 , 2 , 37.6-45.6 mm SL, Rocks with grasses on side of island near Salto Para-Quyuna, río Eretabo , río Caura drainage, 6°18’56”N 64°29’11”W, 30 Nov 2000, F. Provenzano, B. Chernoff, A. Rojas, A. Machado-Allison . FMNH 109900 , 1 , 40.9 mm SL, rocky beach above Salto Para-Quyuna Soodii, río Eretabo, río Caura drainage, 6°18’39”N 64°29’2”W, 30 Nov 2000, F. Provenzano, B. Chernoff, A. Rojas, A. Machado-Allison . MBUCV 26643 , 3 , 30.1-32.8 mm SL, Salto Para, río Arriba , 17 Sep 1993, F. Provenzano, A. Machado, D. Machado, C. Marcano, C. Silvera, A. Rojas . MBUCV 20733 , 4 , 29.6-43.3 mm SL, Raudal Guaiquinima, 2h downstream from Camp Carapo, río Paragua , 19 Feb 1990, S. Ramirez, A. Machado . MBUCV 30202 , 2 , 33.5-45.2 mm SL, río Caura, isla at Raudal del Perro , 5°54’10”N 64°29’27”W, 27 Nov 2000, F. Provenzano, A. Machado, A. Rojas, B. Chernoff . UF 77784 , 1 , 45.5 mm SL, río Erebato , 24 Mar 1984, S. Reid, L . R. Franz .

Diagnosis. Leporinus tepui is distinguished from all other Anostomidae , except Anostomus anostomus (Linnaeus, 1758) , A. brevior Géry, 1961 , A. ternetzi Fernández-Yépez, 1949 , Hypomasticus despaxi (Puyo, 1943) , Leporinus arcus Eigenmann, 1912 , and L. striatus Kner, 1858 , for having four dark longitudinal stripes on body. The new species is distinguished from the species of Anostomus Scopoli, 1777 by having terminal mouth (vs. upturned) and 12 scale series around caudal peduncle (vs. 16); from Hypomasticus despaxi and Leporinus striatus by having four teeth on premaxilla (vs. three), and 12 series of scales around caudal peduncle (vs. 16); and from Leporinus arcus by having 12 series of scales around caudal peduncle (vs. 16) and 34 to 36 scales on lateral line (vs. 36 to 38).

Description. Morphometric data is provided in Tab. 1 . Small size, relative to congeners; largest examined specimen 143.7 mm SL. Head and body elongate and moderately compressed. Dorsal profile gently convex from snout tip to dorsal-fin origin, slightly convex along dorsal-fin base, more or less straight from end of dorsal-fin base to adiposefin origin, and slightly concave from adipose-fin origin to anteriormost dorsal caudal-fin procurrent ray. Ventral profile slightly to strongly concave from lower jaw to vertical through anterior margin of eye, straight to slightly concave from that point to vertical through posterior margin of opercle, convex from latter point to anal-fin origin, slightly convex along anal-fin base, and gently concave from analfin end to anteriormost ventral caudal-fin procurrent ray. Greatest body depth slightly anterior to dorsal-fin origin.

Mouth terminal, its cleft longitudinally aligned with ventral margin of iris. Snout rounded, anteriorly blunt. Premaxillary with four*(27) incisiform teeth gently decreasing in size from symphyseal tooth. Dentary with four*(23) or five(4) incisiform teeth also gently decreasing in size laterally. Teeth with two or three rudimentary cusps in specimens of 50 mm SL or less.

Scale cycloid. Lateral line complete with 34(2), 35*(20), or 36(5) perforated scales, extending from supracleithrum to base of median caudal-fin rays. Horizontal scale rows between dorsal-fin origin and lateral line four*(22) or five(5). Horizontal scale rows between lateral line and pelvic-fin origin four*(27). Horizontal scale rows around caudal peduncle 12*(27). Predorsal scales from dorsal-fin origin to tip of supraoccipital spine 9(7), 10*(11) or 11(8).

Dorsal-fin rays ii,10*(27). Dorsal-fin origin slightly anterior to middle of standard length and to vertical through pelvic-fin origin; its distal margin gently concave. Adipose fin small, teardrop shaped, its origin approximately at vertical through base of last anal-fin ray. Pectoral-fin rays i,14*(9), i,15(12) or i,16(3); fin tip extending more than half the distance between origins of pectoral and pelvic fins; its distal margin slightly convex. Pelvic-fin rays i,8*(26); its distal margin slightly convex. Anal-fin rays ii,8*(26); fin origin approximately at vertical through third scale anterior to adipose-fin origin, when adpressed fin does not reach base of caudal-fin rays; its distal margin slightly concave. Principal caudal-fin rays i,8,9,i*(26). Caudal fin forked, lobes rounded, upper lobe slightly longer than lower lobe.

Coloration. Ground color of head and body light brown and countershaded. Body with four dark longitudinal stripes: dorsalmost stripe almost middorsal, from head to dorsal-fin end, and one scale in depth; second stripe from head above opercle to base of caudal-fin upper lobe, one scale deep; third stripe midlateral, more conspicuous than other stripes, from dorsalmost portion of gill opening to base of median caudalfin rays, two scale depth; fourth stripe from pectoral insertion to anal-fin base, one scale deep. Head with one dark spot immediately posterior to sixth infraorbital, and a dark oblique stripe from top of snout to ventral margin of eye, and extending posteriorly to ventral portion of opercle. Ventral surfaces of head and body pale to cream. All fins uniformly tan.

Geographic distribution. Leporinus tepui is known from tributaries of the río Orinoco basin, in the highlands of the Guyana Shield in Venezuela ( Fig. 2 ).

Ecological notes. Specimens of Leporinus tepui were collected in fast flowing environments among specimens of L. granti , Moenkhausia spp., and other Characiformes ( Chernoff et al., 2003) .

Etymology. The species name comes from the type locality of the new species, a Tepui. The Tepuis are characteristic table-top mountains found in the Guiana Shield highlands. The word Tepui means “house of the gods” in the native tongue of the Pemon, the indigenous people that inhabit the Gran Savana in Venezuela. A noun in apposition.

Conservation status. The species is known only from few specimens collected in a remote, largely subsampled area of Venezuela. However, the apparently broad distribution of the species (at least 20.000 km 2, considering a polygon uniting all known sites), and the fact that the area is relatively well preserved, leads us to consider it as a Least Concern species (LC, following IUCN criteria, IUCN, 2017).

Figures

Fig. 1. Leporinus tepui, new species: (a) FMNH 109898, paratype, 69.6 mm SL; (b) FMNH 45711, holotype, 143.7 mm SL.

Fig. 2. Map of north portion of South America, showing the distribution of Leporinus tepui, new species (squares), and L. arcus (circles). Black symbols represent type localities.