Eurycheilichthys pantherinus ( Reis & Schaefer, 1992 )

Reis, Roberto E., 2017, Unexpectedly high diversity in a small basin: A taxonomic revision of Eurycheilichthys (Siluriformes: Loricariidae), with descriptions of seven new species, Neotropical Ichthyology 15 (1), No. e 160068, pp. 1-28 : 4-6

Eurycheilichthys pantherinus ( Reis & Schaefer, 1992)

Fig. 4; Tabs. 1, 3, 4

Eurycheilus pantherinus Reis & Schaefer, 1992: 217 , figs. 1-5. Type locality: Brazil: Rio Grande do Sul, creek tributary of rio dos Touros, at road from Silveira to Rondinha, Bom Jesus, rio Uruguay basin, approx. 28°42’S 50°10’W.

Eurycheilichthys pantherinus .- Reis & Schaefer, 1993: 894 (new combination).

Diagnosis. Eurycheilichthys pantherinus is distinguished from all congeners, except E. luisae , by possessing a very large lower lip extending to or beyond the anterior margin of the pectoral girdle, and sometimes past the posterior margin (vs. lower lip not reaching the anterior margin of the pectoral girdle). It is distinguished from E. luisae by having the abdomen fully covered by small platelets (vs. partially plated with a middle stripe of platelets), and by a shallower caudal peduncle (7.8-10.2 vs. 10.1-12.5% SL). Eurycheilichthys pantherinus is further distinguished from E. castaneus and E. limulus by the color pattern of its body and head, which are covered by many regular small and roundish dark spots (vs. body and head plain dark brown, without blotches or spot, and possessing a light stripe from the snout tip crossing above the eye and predorsal area); from E. limulus by the wider cleithrum (27.3-32.0 vs. 23.8-26.8% SL); from E. planus and E. vacariensis by the abdomen being fully covered by small platelets (vs. naked or incompletely covered by granular platelets); from E. apocremnus by a shallower caudal peduncle (7.8-10.2 vs. 10.2-12.3% SL); from E. coryphaenus by the parieto-supraoccipital lacking a conspicuous elevation (vs. parieto-supraoccipital conspicuously elevated); and from E. paucidens by the larger orbital diameter (13.4-18.8 vs. 9.3- 12.4% HL), and the presence of numerous (27-51) accessory teeth on the premaxilla in several irregular series (vs. fewer, 2-10 accessory teeth on premaxilla in one irregular series).

Distribution and habitat. Eurycheilichthys pantherinus is most commonly found in the upper rio Uruguay basin in the most northeasterly region of Rio Grande do Sul and southern Santa Catarina, Brazil ( Fig. 5). It also occurs in the upper rio Piratini in Santo Ângelo, rio Buricá in Ijuí, and in the upper rio Uruguay itself and lower courses of its tributaries, as well as the río Yaboti-Guazu, a tributary to the rio Uruguay in Misiones, Argentina ( Azpelicueta, Koerber, 2014). This species is likely distributed widely in the upper rio Uruguay basin. Most of the localities are small rivers and creeks with fast flowing clear water with a substrate comprised of rocks and stones. The capture in the mainstream of the rio Uruguay (MCP 21740) was made during a severe drought in which a rocky portion of the river bed was exposed. These fishes are typically associated with the river bottom, dwelling among the stones and rocks.

Conservation status. Eurycheilichthys pantherinus is relatively frequent and abundant in the upper rio Uruguay basin. The species has an Extent of Occurrence (EOO) of approximately 52,600 km 2 and despite many hydroelectric dams exist in that basin, no specific threats were detected, and the species can be categorized as Least Concern (LC) according to IUCN criteria (IUCN, 2016).

Neotropical Ichthyology, 15(1): e160068, 2017 A revision of Eurycheilichthys

Material examined. Upper rio Uruguay drainage: Brazil: Rio

Grande do Sul State: MCP 13077, holotype, 37.9 mm SL, creek tributary of rio dos Touros on road from Silveira to Rondinha, Bom Jesus (approx. 28º42’S 50º10W) . MCP 13590, 1 paratype, 41.1 mm SL, and MCP 13591, 1 c&s paratype, 40.0 mm SL, collected with the holotype . MZUSP 40337 , 1 paratype, 30.2 mm SL, mouth of creek emptying into rio Pelotas where it crosses the road BR-116, Vacaria (approx. 28º12’S 50º45’W) . MCP 13079, 2 paratypes, 16.7-33.0 mm SL, rio Piratini at Fazenda Hinz , district of Coimbra, Santo Ângelo (approx. 28º47’S 54º20’W) . MCP 22373, 28 , 21.5-48.8 mm SL, 2 c&s, 44.0- 46.2 mm SL, rio Silveira at Silveira, where it crosses the road to Bom Jesus da Serra, São José dos Ausentes (28º37’20”S 49º56’09”W) . MCP 35042, 17 , 24.3-38.2 mm SL, 3 c&s, 23.3-34.8 mm SL, 53 tis, 23.0- 31.9 mm SL, rio dos Touros on road from Rondinha to Silveira, downstream dam, Bom Jesus (28º38’42”S 50º17’01”W) . MCP 26047, 2 , 29.4-30.6 mm SL, rio da Divisa, 4 km W of Silveira, São José dos Ausentes (28º38’16”S 49º57’56”W) . MCP 22370, 1 , 35.1 mm SL, rio da Divisa, between São Jose dos Ausentes and Silveira , São Jose dos Ausentes (28º40’17”S 49º57’57”W) . UFRGS 4892 , 21 , 27.5-46.3 mm SL, rio da Divisa, São José dos Ausentes (28º38’16”S 49º57’56”W) . UFRGS 4914 , 28 , 25.0- 48.2 mm SL, 2 alizarin stained, 44.9-45.5 mm SL, rio do Marco, São José dos Ausentes (28º36’43”S 49º55’11”W) . MCP 25590, 6 , 26.9-36.5 mm SL, rio Buricá on vicinal road from Ijuí to Chiapeta, Chiapeta (approx. 27º57’S 53º57’W) . MCP 18775, 1 , 27.8 mm SL, rio Buricá , downstream from dam, Independência. Santa Catarina State : MCP 47840, 12 , 23.8-36.2 mm SL, rio das Flores, on road from São Miguel do Oeste to Paraíso, Paraíso (26º37’28”S 53º38’55”W) . MCP 22372, 1 , 43.1 mm SL ,

rio Capivaras on road from Silveira to Bom Jardim da Serra,

Bom Jardim da Serra (28º24’21”S 49º38’26”W). MCP 21740, 10 , 14.5-20.3 mm SL, rio Uruguai at Mondai , Santa Catarina (27º05’12”S 53º22’37”W) . MCP 22371, 1 , 45.1 mm SL, rio Taimbezinho, ca. 300m upstream from mouth into rio Pelotas, ca. 20 km from Bom Jardim da Serra towards Santa Bárbara, Bom Jardim da Serra (28º13’45”S 49º36’03”W) . Argentina: Misiones: CI-FML 5875, 6; CI-FML 5876, 2 c&s ; MCP 48035, 2 , 32.9-33.2 mm SL, Arroyo Garibaldi , tributary to río Yaboti- Guazu, near San Pedro (approx. 26º53’S 54º05’W) .

Genseq- 3 16S. MCP 35042; GenBank accession number KX355637 .

Genseq-4 RAG1, RAG2. Sequence data published by Cramer et al. (2011) for RAG1 ( MCP 22373; GenBank accession number GQ214580 ) and RAG2 ( MCP 22373; GenBank accession number GQ225454 ) .

Genseq-4 COI. Sequences deposited in GenBank by Cristian Cramer for COI ( MCP 22373; GenBank accession number EU371000 ) .