Trichomycterus iheringi

description

Redescription: Morphometric data for holotype and paratypes are given in Table 1. “ T 1 ” Body elongate, roughly cylindrical close to head and gradually more compressed in trunk towards caudal fin. Profiles of trunk straight dorsally and slightly convex ventrally. Dorsal and ventral profiles of caudal peduncle straight. Integument thick, especially over base of dorsal and anal fins. Small papillae on lips and scattered over lateral surface of head. Head wide, rounded and depressed, slightly longer than wide, the transversal section at posterior tip of opercle slightly wider than anteriorly at nostril, anterior margin rounded. Lateral region of eye slightly swollen by jaw muscles in both large and small specimens. Profiles of head straight dorsally and convex ventrally. Eyes rounded, well defined rim, dorsally oriented, covered by thin skin, distinctly separated from surface of eyeball. Ocular structures readily visible on surface of skin, not deeply sunken. Orbital rim not free. Anterior nostril same size as posterior one, surrounded by fleshy flap of integument. Posterior nostril with thin flap of integument anteriorly. Anterior and posterior nostrils half diameter of eye. Gill me

A new species of Trichomycterus (Siluriformes: Trichomycteridae) from south Brazil and redescription of T. iheringi (Eigenmann).

diagnosis

Diagnosis: No uniquely derived features were found to diagnose T. iheringi. Trichomycterus iheringi shares with T. castroi, T. davisi, T. guaraquessaba, T. mboycy, T. naipi, T. papilliferus, T. plumbeus, T. stawiarski, and T. zonatus the first pectoral-fin ray not prolonged as a filament and differs from all other congeners from south and southeastern Brazil (T. albinotatus, T. alternatus, T. auroguttatus, T. bahianus, T. brasiliensis, T. candidu, T. caudofasciatus, T. concolor, T. giganteus, T. goeldii, T. immaculatus, T. itacambirussu, T. itatiayae, T. jequitinhonhae, T. landinga, T. longibarbatus, T. maracaya, T. mimonha, T. mirissumba, T. nigricans, T. pantherinus, T. potschi, T. taroba, T. trefauti, T. reinhardti, T. triguttatus, T. variegatus, and T. vermiculatus) by the presence of the first pectoral-fin ray prolonged as a filament. Trichomycterus iheringi shares with the larger assemblage of species congeners from south and southeastern Brazil the presence of two pores s 6 paired at the interorbital space (vs. one symphyseal pore s 6 in T. alternatus, T. giganteus, T. nigricans, and T. paquequerensis). Trichomycterus iheringi shares with T. castroi, T. guaraquessaba, T. plu

A new species of Trichomycterus (Siluriformes: Trichomycteridae) from south Brazil and redescription of T. iheringi (Eigenmann).

discussion

Remarks: The present redescription of Trichomycterus iheringi was based on type material of the CAS and FMNH. The holotype and paratypes were in a good state of preservation (Fig. 2), with the color pattern slightly pale. Eigenmann (1917) presented T. iheringi in a short description based on six specimens which was adequate at the time, but incomplete by current standards. In the next year Eigenmann (1918; PL. 50: 5) presented a transcription of the original description, with a very sharp drawing of the type. Eigenmann (1917, 1918), with no justification, allied T. iheringi to T. punctatissimus Castelnau, from the rio Araguaia (Tocantins basin). Eigenmann (1918; PL. 45: 1) presented a cartoonish drawing of T. punctatissimus from Castelnau (1855), and a short text of the characters in the key of that paper (“ Sides and back with minute dark specks and vermiculations between them; origin of dorsal over origin of ventral ”). It was not possible to analyze the type material of T. punctatissimus, and the original description (Castelnau, 1855) does not offer features to support the relationships of this species to T. iheringi. Only the color pattern cited by Castelnau (1855) for T. punct

A new species of Trichomycterus (Siluriformes: Trichomycteridae) from south Brazil and redescription of T. iheringi (Eigenmann).

distribution

Distribution: Known from the type-locality, Santos, on the costal area of Sao Paulo State, and headwaters of rio Tiete (Parana basin), southeastern Brazil. The Sapina locality cited by Eigenmann (1917 and 1918) for the paratypes was not located. However, Eigenmann (1911) cited “ Sapina, Rio Tiete, into Parana. Coll. Nos. 1599 - 1616. Four miles from the city, July 23, 1908 ”, for the Paratypes. In the same paper, cited “ Santos, coast of Sao Paulo. July 23, 1908 ” [no July 3, 1908 in Eigenmann, 1918] for the Holotype. It is assumed that Sapina is a locality on the headwaters of rio Tiete, close to Santos.

A new species of Trichomycterus (Siluriformes: Trichomycteridae) from south Brazil and redescription of T. iheringi (Eigenmann).