Fig. 1
Rio Uruguay and adjacent drainages showing the distribution of the examined specimens of Gymnogeophagus lipokarenos (dark blue), G. missioneiro (light blue), G. constellatus (red), G. pseudolabiatus (orange), and G. mekinos (yellow). Stars represent the type localities.
Fig. 2
Gymnogeophagus gymnogenys : top, male, UFRGS 17259, 120 mm SL, lagoa Corvina, Mostardas; Rio Grande do Sul, Brazil; bottom, female, uncatalogued, 84 mm SL, Saco da Alemoa, delta do rio Jacuí, Porto Alegre, Rio Grande do Sul, Brazil.
Fig. 3
Measurements and scale counts taken on examined specimens (modified from Reis & Malabarba, 1988Reis, R. E. & L. R. Malabarba. 1988. Revision of the Neotropical cichlid genus Gymnogeophagus Ribeiro, 1918, with descriptions of two new species (Pisces, Perciformes). Revista Brasileira de Zoologia, 4: 259-305., and Reis et al ., 1992Reis, R. E., L. R. Malabarba& C. S. Pavanelli. 1992. Gymnogeophagus setequedas , a new cichlid species (Teleostei: Labroidei) from middle rio Paraná system, Brazil and Paraguay. Ichthyological Exploration of Freshwaters, 3: 265-272.): 1 - Standard length (SL), measured from anterior tip of upper lip to the hypural joint. 2 - Body depth, measured at the maximum depth. 3 - Head length, measured from anterior tip of upper lip to posterior bony margin of opercle. 4 - Dorsal-fin base length, measured from the first spine insertion to the last soft-ray insertion. 5 - Pectoral-fin length, measured from the pectoral-fin base to the tip of the longest ray. 6 - Caudal peduncle depth, measured from the dorsal to the ventral margins of the caudal peduncle at the least depth. 7 - Caudal peduncle length, measured horizontally from the base of the last anal-fin ray to the caudal-fin base. 8 - Eye diameter, measured horizontally between orbital bony margins. 9 - Interorbital width, measured at the point of least bony width. 10 - Upper jaw length, measured from the anterior margin of the upper lip to the posterior tip of the maxilla. 11 - Pre-orbital length, measured from the lower margin of the lachrymal (just above the maxilla) to the orbital rim. 12 - Snout length, measured horizontally from the upper lip to anterior orbital rim. UL - Upper lateral line. LL- Lower lateral line. E1 - Scales in the row immediately above the row that includes the lower lateral line. DL - Scales between dorsal-fin origin and upper lateral line. AL - Scales between anal-fin origin and upper lateral line.
Fig. 4
Gymnogeophagus pseudolabiatus : top,holotype, male, MCP 35027, 92.3 mm SL, rio Sarandi III, on the road from Santana do Livramento to Quaraí, Santana do Livramento, Rio Grande do Sul, Brazil; bottom, paratype, male, MCP 35036, 81.4 mm SL) creek tributary of rio Quaraí, on road from Quaraí to Baltazar Brum railroad station, Rio Grande do Sul, Brazil.
Fig. 5
Gymnogeophagus pseudolabiatus : top, paratype, male, UFRGS 7754, 102.0 mm SL, arroyo Cuaró Grande on Ruta 4, tributary of rio Quaraí, Artigas, Uruguay; bottom, paratype, female, UFRGS 7754, 80.5 mm SL, arroyo Cuaró Grande on Ruta 4, tributary of rio Quaraí, Artigas, Uruguay.
Fig. 6
Lower pharyngeal tooth plates in occlusal view: a, G. pseudolabiatus , MCP 11228, 71.6 mm SL; b, G. mekinos , MCP 11251, 84.2 mm SL; c, G. constellatus , MCP 10827, 91.4 mm SL; d, G. missioneiro , MCP 12725, 59.3 mm SL; e, G. lipokarenos , MCP 12991, 89 mm SL. Scale bars = 1 mm.
Fig. 7
Rio Sarandi III, on the road from Santana do Livramento to Quaraí, Santana do Livramento, Rio Grande do Sul, Brazil, type locality of Gymnogeophagus pseudolabiatus .
Fig. 8
Gymnogeophagus mekinos : top, holotype, male, MCP 19296, 92.4 mm SL, rio Piraizinho, on the road from Bagé to Dom Pedrito, tributary of rio Negro, Rio Grande do Sul, Brazil; middle, paratype, male, UMMZ 225495, 94.5 mm SL, collected with the holotype; bottom, paratype, female, UFRGS 7402, 77.5 mm SL, arroio Batovi na rota 5 à 20 km de Tacuarembó, no km 365,6, drenagem do rio Tacuarembó, bacia do rio Negro, Tacuarembó, Uruguay.
Fig. 9
Gymnogeophagus constellatus : top, holotype, male, MCP 10499, 117.3 mm SL, rio Conceição, Ijuí, Rio Grande do Sul, Brazil; middle, paratype, male, UFRGS 7094, 136.1 mm SL; bottom, paratype, female, UFRGS 7094, 92 mm SL, creek on the road to Pirapó, São Nicolau, Rio Grande do Sul, Brazil.
Fig. 10
Gymnogeophagus missioneiro : top, holotype, male, MCP 23495, 109.3 mm SL, arroio Ximbocuzinho, on the road from São Luiz Gonzaga to Bossoroca, 4 km from São Luiz Gonzaga, Rio Grande do Sul, Brazil; middle, paratype, female, MCP 12725, 72.8 mm SL, arroio Passo do Rosário or Passo da Cancela, on the road from São Nicolau to Garruchos, Santo Antônio das Missões, Rio Grande do Sul, Brazil; bottom, holotype, photo taken just after capture.
Fig. 11
Gymnogeophagus lipokarenos : top, holotype, male, MCP 23522, 108.5 mm SL, rio Dourados at Linha Várzea, on the road from Severiano de Almeida to Aratiba, Rio Grande do Sul, Brazil; bottom, holotype, photo taken just after capture.
Fig. 12
Gymnogeophagus lipokarenos : top, paratype, male, UFRGS 15752, 115 mm SL, arroio do Tigre, tributary of the rio Turvo, Três Passos, Rio Grande do Sul, Brazil; bottom, paratype, female, UFRGS 15743, 107 mm SL, arroio Lajeado Romana, Três Passos, Rio Grande do Sul, Brazil.
Fig. 13
Species of Gymnogeophagus from Rio Grande do Sul State, Brazil. a, Gymnogeophagus balzanii , male, UFRGS 9148, 131.8 mm SL, barragem Sanchuri, Uruguaiana. b, G. balzanii , female, UFRGS 7015, 86 mm SL, barragem Sanchuri, Uruguaiana. c, G. meridionalis , male,UFRGS 8404, rio Negro, BR-153, between Aceguá and Bagé. d, G. rhabdotus ,male, uncat., 65 mm SL, EEA-UFRGS, Eldorado do Sul. e, G. labiatus , male, uncat., 117 mm SL, lago Guaíba. f, G. labiatus , female, uncat.,104 mm SL, Barra do Ribeiro. g, G. lacustris , male, UFRGS 16751, 128 mm SL, lagoa Corvina, Mostardas. h, G. lacustris , female, UFRGS 16751, 90 mm SL, lagoa Corvina, Mostardas. i, G. tirapare , male, uncat., rio Cacequi. j, G. tirapare , female, UFRGS 16642, rio Santa Maria, Rosário do Sul.