234 FISHES OF WESTERN SOUTH AMERICA 
The upper, or intercordilleran, Maranon 
“A Knodus but for the nature of the second suborbital.”’ 
Base of caudal sealed, scales rather large and extending back along the middle 
of the caudal lobes; lateral line complete; second suborbital not in contact with the 
preopercle below, leaving a wide naked area. 
281. MoENKHAUSIA OVALIS (Giinther) 
Tetragonopterus ovalis Giinther, 1868, Proc. Zool. Soc. London, 245, one four-inch specimen from 
the Bartlett collection, Xeberos; 
Eigenmann and Higenmann, 1891, Proc. U.S. Nat. Mus., XIV, 53; 
Fowler, 1906, Proe. Acad. Nat. Sci. Phila., 441, fig. 38, Maranon; 
Regan, 1913, Ann. Mag. Nat. Hist., (8), VIII, 281, Rio Ucayali. 
Tetragonopterus chalceus in part, Cope, 1878, Proc. Amer. Phil. Soc., XVII, 691, Rio Marafion. 
Moenkhausia ovalis Bigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 437; 
Eigenmann, 1917, Mem. Mus. Comp. Zool., XLIII, i, 87, pl. vii, fig. 3. 
Maranon basin 
Depth 2; maxillary with two teeth and extending beyond anterior margin of 
eye; dorsal contour slightly convex and only slightly depressed at the head; a faint 
humeral spot; a caudal spot not reaching end of middle caudal rays, diffuse; iris 
reddish brown. 
Genus 106: KNODUS Eigenmann 
Knodus Kigenmann, 1911, Ann. Mag. Nat. Hist., (8), VII, 216; 
Eigenmann, 1918, Mem. Mus. Comp. Zool., XLIIT, ui, 114. 
Type: Anodus meridae Kigenmann 
Rios Tapajos, Tocantins and Paraguay to Venezuela 
Near Moenkhausia; second suborbital reaching preopercle below; four teeth in 
the second row of the premaxillary; caudal scaled at the base; lateral line slightly 
decurved. 
282. KNopUS MOENKHAUsI (Higenmann and Kennedy) 
Poecilurichthys moenkhausii Eigenmann and Kennedy, 1903, Proc. Acad. Nat. Sci. Phila., 522, 
Arroyo Trementina. 
Bryconamericus moenkhausii Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 434. 
Knodus moenkhausti Pearson, 1937a, Proc. Cal. Acad. Sci., (4), XXIII, 91, Rio Pusoe, 
upper Maranon. 
Upper Amazon to Middle 
283. KNopUS BREVICEPS (Higenmann) 
Bryconamericus breviceps Kigenmann, 1908, Bull. Mus. Comp. Zool., LIT, 105, Goyaz; 
Rigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, IIT, 434. 
Knodus breviceps Kigenmann, 1918, Mem. Mus. Comp. Zool., XLII, ii, 118, pl. x, fig. 2; 
Pearson, 1937a, Proc. Cal. Acad. Sci., (4), X XIII, 91, Tingo de Pauca and Rio Pusoc, upper 
Maranon. 
