Leporinus paranensis Garavello & Britski, 1987

Britski, Heraldo A., Garavello, Júlio C., Oliveira, Claudio & Birindelli, José L. O., 2024, Bisecting the type series of Leporinus paranensis Garavello & Britski, 1987 (Characiformes, Anostomidae), Papéis Avulsos de Zoologia 64, pp. 1-13 : 2-6

Leporinus paranensis Garavello & Britski, 1987 ( Fig. 1 )

Leporinus paranensis Garavello & Britski, 1987: 156 , fig. 1B [Rio Grande at Marimbondo, 20°10′S 49°10′W] [in part, only MZUSP 14453, and MZUSP 14454]. – Oyakawa, 1996: 476-477 [type catalog, in part, only MZUSP 14453, and MZUSP 14454]. – Pérez-Jr. & Garavello, 2007: 331 [Rio do Pântano, tributary of Rio Mogi-GuaÇu, LISDEBE uncat., MZUEL 22894]. – Apone et al., 2008: 102, fig. 7-36 [Rio Quilombo,Rio do Pântano, tributary of Rio Mogi-GuaÇu, LISDEBE 1417]. – Oliveira et al., 2009: 492 [tributaries of the Mogi GuaÇu river, LISDEBE 1417].

Type specimens: MZUSP 14453, holotype, 1 alc, 170.9 mm SL, Marimbondo, Rio Grande, SP, 20 Nov 1975. MZUSP 14454, paratypes, 2 alc, 154.6-162. 6 mm SL, collected with holotype.

Remarks: The type locality was likely flooded by the hydroelectric dam of U.H.E. Marimbondo, and it herein interpreted as São Paulo state, Guaraci municipality, Rio Grande at Marimbondo, c. 20°15′S 49°05′W.

Non-type specimens: Brazil, São Paulo state, Rio Grande basin. LIRP 3828, 1 alc, 45.0 mm SL, Luís Antônio, Rio Mogi-GuaÇu, near EstaÇão Ecológica de Jataí, 21°36′44″S 47°49′09″W, 01 Oct 2002. LIRP 4919, 1 alc, 49.0 mm SL, Luís Antônio, Rio Mogi-GuaÇu, near EstaÇão Ecológica de Jataí, 21°36′44″S 47°49′09″W, 01 Oct 2002. LISDEBE 1417, 1 alc, 124.72 mm SL, São Carlos, Rio Quilombo, tributary of the Rio Mogi-GuaÇu, 21°46′23″S 47°46′44″W, F. Apone, A.K. Olivera & J.L.O. Birindelli, 03 Jun 2004. LISDEBE uncat., 1 alc, 148.14 mm SL, São Carlos, Ribeirão do Pântano, tributary of the Rio Mogi-GuaÇu, 21°51′46.5″S 47°40′25.5″W, O.R. Pérez-Jr. & L.H. Silva, 30 Mar 2001. MZUEL 22894, 1 alc, 125.13 mm SL, São Carlos, Ribeirão do Pântano, a tributary of Rio Mogi-GuaÇu, 21°51′46.5″S 47°40′25.5″W, O.R. Pérez-Jr. & L.H. Silva, 01 Jun 2001. MZUSP 62409, 1, 64.2 mm SL, Pirassununga, Mogi-GuaÇu river at Cachoeira de Emas, 21°55′S 47°23′W, 14 Oct 1950, W. Bockermann.

Remarks: Benedito-Cecilio et al. (2004: 375) identified specimens collected in tributaries of rio Paranaíba, at Parque Nacional de Emas (including NUP 792, NUP 793, NUP 799, NUP 800, NUP 810, NUP 1949, NUP 2310) as Leporinus paranensis . However, the examination of these specimens revealed that these do not belong to L. paranensis , but rather to L. octofasciatus . The coloration of these specimens is faded (i.e., the dark transversal bars are not as conspicuous as most specimens of L. octofasciatus ), which could have led to the misidentification. These specimens have more lateral-line scales (37 or 38) than specimens herein identified as L. paranensis (35 or 36). A similar case of misidentification occurred in Avelino et al. (2015) (see Discussion for further information).

Diagnosis: Leporinus paranensis is distinguished from congeners, except L. amae , L. amblyrhynchus , L. bahiensis , L. bistriatus , L. bleheri , L. desmotes , L. enyae , L. guttatus , L. inexpectatus , L. marcgravii , L. melanopleura , L. microphthalmus , L. microphysus , L. moralesi , L. multimaculatus , L. octofasciatus , L. octomaculatus , L. reticulatus , L. sexstriatus , L. striatus , L. taeniatus , L. taeniofasciatus , L. torrenticola , and L. tigrinus by having three premaxillary teeth (vs. four). Leporinus paranensis is distinguished from L.amae , L.amblyrhynchus , L.bistriatus , L. bleheri , L. desmotes , L. enyae , L. guttatus , L. marcgravii , L. melanopleura , L. microphthalmus , L. microphysus , L. moralesi , L. multimaculatus , L. octofasciatus , L. octomaculatus , L. reticulatus , L. sexstriatus , L. striatus , L.taeniatus , L.taeniofasciatus , L.torrenticola , and L.tigrinus by having three dark midlateral blotches on the body (vs. body with dark transversal bars in L. bleheri , L. desmotes , L. enyae , L. octofasciatus , and L. tigrinus , or body with a dark midlateral stripe in L. amae , L. amblyrhynchus , L. bistriatus , L. melanopleura , L. melanopleurodes , L. microphysus , L. moralesi , L. sexstriatus , L. sidlauskasi , L. striatus , L. taeniatus , L. taeniofasciatus , or body with four to eight dark midlateral blotches in L. guttatus , L. marcgravii , L. microphthalmus , L. multimaculatus , L. octomaculatus , L. reticulatus , L. torrenticola ). Leporinus paranensis is distinguished from L. bahiensis and L. inexpectatus by having 16 scale rows around caudal peduncle (vs. 12).

Description: Morphometric data in Table 2. Medium-sized species, largest known specimen 170 mm SL. Head and trunk elongate and moderately compressed. Dorsal profile strongly convex from tip of upper lip to anterior naris, straight from this point to tip of supraoccipital spine, somewhat straight from there to origin of dorsal fin; dorsal-fin base straight; slightly convex from terminus of dorsal-fin base to origin of adipose fin and distinctly concave on dorsal margin of caudal peduncle. Ventral profile convex from tip of lower lip to the vertical through anterior naris, straight from this point to vertical through pectoral-fin origin; straight or somewhat convex from latter point to origin of anal-fin; anal base straight and concave on ventral margin of caudal peduncle. Body depth greatest at origin of dorsal fin.

Mouth terminal, opening longitudinally aligned with ventral margin of pupil in large specimens (100 mm SL or more). Lips smooth or slightly fringed. Premaxillary with three unicuspid teeth gradually decreasing in size away from symphyseal tooth. Dentary with four unicuspid teeth decreasing in size postero-laterally.

Scales large and cycloid with 5 or 6 radii. Lateral line extending from supracleithrum to base of caudal-fin median rays, with 35*(3) or 36(3) pored scales. 4*(3) or 5(3) longitudinal series of scales between dorsal-fin origin and lateral line, and 5*(6) series of scales between lateral line and pelvic-fin origin. 16*(6) longitudinal series of scales around caudal peduncle, with at least three specimens (LISDEBE uncat.,MZUEL 22894, MZUSP 14454) having scale rows irregular and slightly fewer than 16 rows on part of caudal peduncle. Middorsal line with 10(1) or 11*(5) scales between supraoccipital tip and dorsal-fin origin.

Dorsal fin ii, 10*(6); its origin slightly anterior to midpoint of standard length and anterior to vertical through pelvic-fin origin. Distal margin of dorsal-fin convex. Adipose fin small, its origin posterior to origin of anal fin by diameter of one or two scales. Pectoral fin i,14(3) or i,15*(3); its margin slightly convex;its tip when adpressed extending to fourth or fifth scale anterior to pelvic-fin origin. Pelvic fin i,8*(6); its margin concave. Anal fin ii,8*(6), distal margin concave in most specimens; rays not reaching the caudal fin base when adpressed. Caudal fin i,8,9,i*(6); fin distinctly forked with approximately symmetrical lobes.

Coloration: Body ground coloration brown to yellow, distinctly countershaded. Three large rounded to oval dark-brown blotches on midlateral portion of trunk, each larger than orbit (blotches nearly rectangular in a couple of specimens). Anteriormost blotch ventral to dorsal-fin base; median one between dorsal-fin terminus and adipose fin; and posterior one on posterior half of caudal peduncle.Trunk with eight to 12 dark transversal bars on dorsum and extending ventrally below lateral line; bars much less conspicuous than midlateral blotches, being fragmented in larger specimens forming inconspicuous blotches. Inconspicuous dark lines between scale series present on median and posterior half of lateral portion of trunk in some specimens, including the holotype, but absent in recently collected specimens. Dark inconspicuous spot on base of trunk lateral scales in some of the recently collected specimens (absent on holotype). Head distinctly countershaded; upper lip dark. Fins hyaline or uniformly tan, except for adipose fin with dark distal margin.

Distribution: Leporinus paranensis is known from the type specimens collected in the Grande river, in an area currently flooded by the hydropower dam UHE Marimbondo; and from specimens collected in tributaries of the Mogi-GuaÇu river,itself a tributary of the Grande river ( Fig. 2 ).

Conservation status: The apparently rarity of Leporinus paranensis is puzzling. The distribution of the species is at best speculative and its abundance and biology in the wild are completely unknown. The fact that the type series was collected almost 50 years ago in an area that has been largely altered by the construction of a hydroelectric dam is a concern. However, the putative distribution of the species (in at least the Grande River basin) is relatively broad, encompassing parts of the states of São Paulo, and Minas Gerais. The species has been recently recorded (2003-2007) from tributaries of the Mogi-GuaÇu river in areas where no potential impacts are expected in the near future. Furthermore, the species is not commercially relevant and does not suffer under any direct anthropological impact (such as overfishing, for example). Therefore, given the IUCN criteria, the species is herein recommended to be considered as Least Concern (LC).

Figures

Figure 1. Leporinus paranensis, holotype, MZUSP 14453, 170.9 mm SL, rio Grande at Marimbondo (above); MZUEL 22894, 125.1 mm SL, Ribeirão do Pântano, tributary of rio Mogi-Guaçu (below,a better color-preserved specimen).

Figure 2. Geographical distribution of Leporinus paranensis (circles) and L. inexpectatus (squares) in southeast South America. Open symbols represent the type localities.