Sternarchorhynchus curumim

distribution

Distribution: Tefé River, Amazonas, Brazil (de Santana, Vari, 2010 b).

Checklist of Gymnotiformes (Osteichthyes: Ostariophysi) and catalogue of primary types

biology_ecology

Ecology. Sternarchorhynchus curumim is known only from the type series captured at depths of 5 – 14 m in the Rio Tefé towards the end of the low­water period. The Rio Tefé is a typical nutrient poor blackwater river with low electrical conductivity (6 – 20 Scm­ 1). All four specimens were in reproductive condition. The females possessed swollen ovaries containing large yellow globular eggs typical of spawning fish. The male specimen had enlarged white testes typical of a spawning specimen. The stomachs of all specimens contained only autochthonous invertebrates, mainly the larvae of Chironomidae, Coleoptera and Plecoptera.

Sternarchorhynchus curumim (Gymnotiformes: Apteronotidae), a new species of tube-snouted ghost electric knifefish from the low- land Amazon basin, Brazil

description

Description. Morphometric data for holotype and paratypes are presented in Table 1. Body laterally compressed, with greatest body depth at abdominal cavity or a little posterior to this area. Dorsal profile nearly straight. Lateral line extending to tail, but absent on caudal fin. First anterior perforated scale of lateral line above pectoral­fin origin (Fig. 1). Head laterally compressed, widest at opercular region and deepest at nape; snout elongate, compressed and curved downward. Eyes small, located laterally on head, and completely covered by a thin membrane. Anterior nares at end of a small tube, close to tip of snout; posterior ones ellipsoid, without a tube and closer to tip of snout than to eyes. Branchial opening slightly anterior to pectoral­fin origin; branchial membranes joined at isthmus. Anus and urogenital papilla adjacent, ventral, located in a vertical posterior to eyes, does not noticeable move anteriorly with age. Neurocranium partially reticulated. Infraorbital series not ossified. Mesethmoid long and narrow. Lateral ethmoid absent. Premaxillae of small size, somewhat rounded, seven to 10 teeth (n = 1). Dentary elongate, a row of seven curved conical teeth (n =

Sternarchorhynchus curumim (Gymnotiformes: Apteronotidae), a new species of tube-snouted ghost electric knifefish from the low- land Amazon basin, Brazil

description

Sternarchorhynchus cf. curvirostris. Brazil: Amazonas: INPA 4834, 1, 189, Rio Uatumã, Balbina near of dam, J. Zuanon, et al., 24 Oct 1987. INPA 11523, 1, 291, Paraná Afoia, 10 Km west of the community ‘ mouth of Mamirauá’, Alvarães, Rio Solimões, 03 ° 2 ’ S 64 ° 51 ’ W. INPA 11331, 1, 137, Rio Negro, Lago do Prato, Novo Airão, M. Garcia, 17 Mar 1991. INPA 19992, 1, 222, Rio Amazonas, Paraná do Tapará, C. Cox­Fernandes, 0 3 Nov 1992. Pará: INPA 3931, 2, 170 – 184, Rio Xingu, Cachoeira de Kaituká, L. R. Py­Daniel & J. Zuanon, 0 9 Oct 1990. INPA 3934, 3, 99 – 130, Rio Xingu, Cachoeira de Kaituká, L. R. Py­Daniel & J. Zuanon, 0 9 Oct 1990. Sternarchorhynchus mesensis. Brazil: Goias: MNRJ 11611, paratypes 4 c & s, Rio Tocantins, local of the future hydroelectric dam Serra da Mesa, Minaçu, Cavalcante, 13 ° 50 ’ S 48 ° 19 ’ W, D. F. Moraes et al., 24 – 31 Jul 1988. MNRJ 11613, paratypes 7, 115 – 250, Rio Tocantins, local of the future hydroelectric dam Serra da Mesa, Minaçu, Cavalcante, 13 ° 50 ’ S 48 ° 19 ’ W, D. F. Moraes et al., 24 – 31 Jul 1988. Sternarchorhynchus mormyrus. Brazil: Amazonas: INPA uncat., 1, 213, Costa do Morimba, Ilha do Careiro, C. Cox­Fernandes, Jan 1998. INPA uncat

Sternarchorhynchus curumim (Gymnotiformes: Apteronotidae), a new species of tube-snouted ghost electric knifefish from the low- land Amazon basin, Brazil