126 FISHES OF WESTERN SOUTH AMERICA 
77. PLATYDORAS cosTaTus (Linnaeus) 
Silurus costatus Linnaeus, 1766, Syst. Nat., ed. xu, 506. 
Cataphractus costatus Bloch, 1794, Ausl. Fische, VIII, 82, pl. 376. 
Doras costatus Lacépéde, 1803, Hist. Nat. Poiss., V, 116, part; 
Cuvier and Valenciennes, 1840, Hist. Nat. Poiss., XV, 268; 
Castelnau, 1855, Anim. Amér. Sud, Poiss., 48, Amazon; 
Giinther, 1864, Cat. Fish. Brit. Mus., V, 201; 
Eigenmann and Eigenmann, 1890, Occ. Papers Cal. Acad. Sci., I, 231; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 393. 
Doras armatulus Miller and Troschel, in Schomburgk, 1848, Reisen, III, 629; 
Steindachner, 1882 (1883), Denksch. KIx. Akad. Wiss. Wien, XLVI, 5, one, 90 mm., Rio 
Huallaga. 
Platydoras costatus Bleeker, 1863, Nederl. Tijdsch. Dierk., I, 16, 86; 
Eigenmann, 1925, Trans. Amer. Phil. Soc., XXII, 316, pl. 1, figs. 5 and 14; pl. ii, figs. 1 and 2; 
pl. ix, figs. 1-3. 
Widely dispersed from the Guianas and Para to the Andes of Peru and Bolivia. 
15874, 3, 59-81 mm., Yarinacocha, Yurimaguas, Allen, September, 1920. 
15875, 5, 77-81 mm., Rio Morona, Allen, October, 1920. 
Genus 36: AGAMYXIS Cope 
Doras Cope, 1870, Proc. Amer. Phil. Soc., XI, 568, Pebas; 
Cope, 1871, Proc. Acad. Nat. Sci. Phila., X XIII, pl. iii; 
Kigenmann and Eigenmann, 1890, Occ. Papers Cal. Aead. Sei., I, 241. 
Doras (Agamyxis) Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, IIT, 393. 
Agamyxis Cope, 1878, Proc. Amer. Phil. Soc., XVII, 101; 
Eigenmann, 1925, Trans. Amer. Phil. Soc., XXII, 322. 
Type: Agamyxis pectinifrons Cope 
Peruvian Amazon 
Distinguished from nearby genera Acanthodoras and Astrodoras by the cover- 
ing of spiny plates over caudal peduncle above and below; alike in lack of serrae 
on rear of dorsal spine; nasal plate erect and pectinate; eye in anterior half of head; 
caudal rounded. 
78. AGAMYXIS PECTINIFRONS (Cope) 
Doras pectinifrons Cope, 1870, Proc. Amer. Phil. Soc., XI, 568, Pebas; 
Eigenmann and Higenmann, 1890, Occ. Papers Cal. Acad. Sci., I, 241. 
Agamyxis pectinifrons Cope, 1878, Proc. Amer. Phil. Soc., XVII, 679; 
Eigenmann, 1925, Trans. Amer. Phil. Soc., X XII, 322, pl. xvi, fig. 4; text fig. 19. 
Known from the type in the Philadelphia museum. 
79. AGAMYXIS FLAVOPICTUS (Steindachner) 
Doras flavopictus Steindachner, 1908, Sitzb. KK. Akad. Wiss. Wien, VII, 3, Iquitos. 
Doras (Agamyxis) flavopictus Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, IIT, 393. 
Agamyxis flavopictus Eigenmann, 1925, Trans. Amer. Phil. Soc., XXII, 323. 
