ANNOTATED LIST OF THE SPECIES 191 
Peruvian Amazon 
178. LASIANCISTRUS PICTUS (Castelnau) 
Hypostomus pictus Castelnau, 1855, Anim. Amér. Sud, Poiss., 44, pl. xxii, fig. 2. 
Ancistrus (Lasiancistrus) pictus Regan, 1904, Trans. Zool. Soc. London, XVII, 237. 
Lasiancistrus pictus Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 409. 
Rio Ucayali 
One poor specimen known. 
Genus 82: CHAETOSTOMA Heckel 
Hypostomus (in part) Cuvier and Valenciennes, 1840, Hist. Nat. Poiss., XV, 489. 
Ancistrus (in part) Kner, 1854, Denksch. KKK. Akad. Wiss. Wien, VII, i, 272. 
Chaetostoma Heckel, in Tschudi, 1846, Fauna Peru., 25, loborhynchus; 
Jordan, 1919, Genera of Fishes, IT, 230. 
Chaetostomus Ikner, 1854, Denksch. Kx. Akad. Wiss. Wien, VII, i, 271 with an unjustified change 
of spelling; 
Bleeker, 1863, Nederl. Tijdsch. Dierk., I, 78, loborhynchus; 
Giinther, 1864, Cat. Fish. Brit. Mus., V, 240; 
Eigenmann and Higenmann, 1889, Proc. Cal. Acad. Sei., (2), II, 46; 
Eigenmann and Eigenmann, 1890, Occ. Papers Cal. Acad. Sci., I, 443; 
Regan, 1904, Trans. Zool. Soc. London, XVII, 244; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 410, and of authors gene- 
rally. 
Type: Chaetostoma loborhyncha Tschudi 
Mountain regions northwestern South America, from the Chagres basin to 
that of the Beni in Bolivia 
Hypostomatinae having a narrow, naked area about the snout, and free from 
tentacles; mouth wide, mandible about equal to the interorbital; lower surfaces 
generally naked. 
The species restricted usually to limited areas in the interandine valleys due to 
effective barriers. In this they show a similar distribution pattern to that found 
in plants, molluscs, and even in such winged forms as the butterflies. 
179. CHAETOSTOMA FURCATA Fowler 
Chaetostomus furcatus Fowler, 1939 (1940), Proc. Acad. Nat. Sci. Phila., NCI, 238, figs. 28 and 29. 
The Ucayali, Contamana 
Kknown from the unique specimen at the Philadelphia Academy, the type, 
127 mm., named for the very long, forked caudal fin. 
180. CHAETOSTOMA TACZANOWSKIL Steindachner 
Chaetostomus taczanowskii Steindachner, 1882, Denksch. KKK. Akad. Wiss. Wien, XLVI, 23, pl. v, 
figs. 2 and 2a, R. Huambo; 
