All Fishes ⇒ Auchenipteridae ⇒ Auchenipterinae ⇒ The genus Tetranematichthys

Hop to next section Summary of tetranematichthys
Etymology Tetranematichthys: From the Greek tetra, meaning four, nema, meaning filament, and ichthys, meaning fish; in reference to the number of barbels.
Identification 1. Lateral margin of head at anterior portion of orbit, parallel to the posterior limit of operculum, in ventral view (Fig. 5a); ventral region light or dark colored; presence or absence of digit-like projections on distal portion of mandibular barbel; length of mandibular barbel 5.2- 2.6% HL; length of main ray of upper caudal-fin lobe 14.5- 20.5% SL; body width at pectoral-fin insertion 82.1- 110.0% HO; head length 24.4- 31.0% SL ..................................................2 1a. Lateral margin of head at anterior portion of orbit, diverging laterally to posterior limit of operculum, in ventral view (Fig. 5b); uniform colour pattern with dark patches along the body; presence of digit-like projections on distal portion of mandibular barbel; length of mandibular barbel 6.3-23.5% HL; length of main ray of upper caudal-fin lobe 18.1-19.9% SL; body width at pectoral-fin insertion 117.0125.0% HO; head length 28.5-32.3% SL ............................................. .............................................................. T. quadrifilis (rio Guaporé Basin) 2. Dorsal region without blurred light area; dark patches of pigmentation present along the body; ventral region dark-coloured; one light coloured stripe present on the caudal-fin; pelvic-fin without distinct light coloured stripe; anterior margin of mandibular barbel with digit-like projections; length of mandibular barbel 7.4-24.6% HL; snout length 41.2-49.3% HL; body width at pectoral-fin insertion 69.279.3% HL ................................................... T. wallacei (rio Tocantins, rio Orinoco and several stretches of the rio Amazon, except rio Guaporé) 2a. Dorsal region with blurred light area; dark patches of pigmentation absent along the body; ventral region light-coloured; two light-coloured stripes present on the caudal fin; pelvic-fin with distinct light coloured stripe; anterior margin of mandibular barbel serrated on distal portion; length of mandibular barbel 4.5-6.0% HL; snout length 28.834.5% HL; body width at pectoral-fin insertion 82.1-88.7% HL..................T. barthemi (rio Saracá, rio Araticum and rio Urubu).
Size Smallest 160mm, largest 206mm, average 180mm, most commonly 160mm. All SL.
Species There are 3 "species" in the database
New spp. / time
1750 1770 1790 1810 1830 1850 1870 1890 1910 1930 1950 1970 1990 2010 
Distribution

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