New Steindachnerina Species (Teleostei: Characiformes: Curimatidae) from the Rio Tocantins Drainage

A new species, Steindachnerina notograptos, is described from the middle portions of the Rio Tocantins drainage, Brazil. The possession of a small, fleshy, lobulate body situated on each side of the posterior limit of the medial fold of the buccopharyngeal complex is autapomorphic for S. notograptos. The combination of other aspects of the buccopharyngeal complex along with meristic and pigmentation features further distinguish the species from all of its congeners.

Resumen

Uma nova espécie, Steindachnerina notograptos, é descrita da porção média da drenagem do rio Tocantins no Brasil. A possessão de somente um par de pequenos corpos lobulados situados em cada lado da porção posterior da prega mediana do complexo bucofaríngeo é autapomórfica para S. notograptos. A combinação de outros aspectos do complexo bucofaríngeo com caracteres merísticos e de pigmentação distingue a espécie de todas suas congêneres.

Fig. 1

Steindachnerina notograptos, holotype, MCP 42579, 89.8 mm SL, Paranã, Rio Palmas, Rio Tocantins drainage, Tocantins, Brazil.

Fig. 2

Roof of buccopharyngeal region and anterior portion of gill arches of Steindachnerina notograptos, UNT 7726, paratype, showing various elaborations in that region. Hyoid apparatus, ventral portion of gill arches, eyes, and associated tissues removed. Abbreviations: apf, anterior posteromedian flap; lf, lateral fold; mf, median fold; mlb, medial lobulate body; plp, posterior lobulate process; ul, upper lip.

Fig. 3

Map of Rio Tocantins basin, Brazil, showing collection localities of Steindachnerina notograptos (dots; T = type locality). Some symbols represent more than one lot and/or locality.

Fig. 4

Most parsimonious cladogram depicting hypothesis of phylogenetic relationships among species of Steindachnerina. Length = 49. Consistency Index = 0.69. Retention Index = 0.90. See Appendix 1 for descriptions of characters and characters states. Numbers above branches are node numbers, and, in the following listing, character codes are followed by character-state transformations (codes in parentheses refer to ambiguous optimizations): (1): 5-1, 6-1(6-2), 8-1, 10-1, 25-1(25-0); (2): 3-1, 24-1, (25-1); (3): 9-1, 15-1, 16-1, 17-1, 20-1, 21-1; (4): 22-1; (5): 24-0, 25-0, 26-1, 27-1, 28-1; (6): 1-1, 2-1, 4-1, 6-2 (6-1), (25-1); (7): 23-2; (8):1-2, 7-1; (9):1-3, 11-1, 12-1; (10): 13-1, 14-1; (11): 23-1; (12): 25-0; (13): 18-1, 19-1, 26-1, 27-1, 29-1; (14): 23-0; (15): 19-2. Known autapomorphies including autapomorphic reversals for species of Steindachnerina (character and character states as in Appendix 1): S. notograptos: 22-1, 26-1, 28-1, 29-1; S. biornata: 25-0; S. dobula: 25-0; S. quasimodoi: 2-0; and S. hypostoma: 25-0. Other species in the genus lack identified autapomorphies.

Contributor Notes

Associate Editor: C. J. Ferraris.

¹ Laboratório de Ictiologia Sistemática, Universidade Federal do Tocantins, Campus de Porto Nacional, Caixa Postal 136, 77500-000 Porto Nacional, Tocantins, Brazil; E-mail: lucinda@uft.edu.br.

² Division of Fishes, Department of Vertebrate Zoology, MRC-159, National Museum of Natural History, P.O. Box 37012, Smithsonian Institution, Washington, D.C. 20013-7012; E-mail: varir@si.edu. Send reprint requests to this address.

Received: 30 Apr 2008

Accepted: 30 Sept 2008