Pearson: Fishes of the Rio Beni Basin 
25 
Loricaria beni Pearson, sp. nov., Plate V, fig. 4. 
17016, 3 cotypes, 65-78 mm., Lagoons, Lake Rogoagua. Nov., 1921. 
Head 4.6 to 4.8; width of the head 1.4 to 1.5 times in its 
length; eye 6.4 to 6.8; interorbital 3.3 to 3.5; snout 2 to 2.1; 
width of the first anal ray 4 times in its distance from the cau- 
dal ; scutes 14 to 15, the keels entirely united on the posterior 
scutes; lips papillose, their margins with few short fringes; 
the lower lips not near reaching the gill opening ; free part of 
the barbel equal to the eye diameter ; 5 to 7 teeth in each side 
of each jaw; lower surface of the head naked; depth of the 
orbital notch equal to slightly more than V 2 °f the eye diame- 
ter ; anal plate bordered by 3 plates ; ventral buckler formed by 
10 plates; 3 series of plates between the lateral plates, the 
plates becoming more numerous and irregular on the anterior 
third ; the armature not quite extending to the anterior angle 
of the gill opening; pectorals extending slightly beyond the 
base of the ventrals, the ventrals reaching beyond origin of 
the anal; upper caudal ray prolonged a distance equal to 2/5 
the length to the base of the caudal. 
5 dark cross bands, the first thru the first 4 dorsal rays, 
the posterior edge of the second below the tip of the depressed 
dorsal ; outer third of the first dorsal ray dark ; dorsal rays 
obscurely spotted, the interradial membrane hyaline ; pec- 
torals, dorsal, and anal with irregular spots most distinct at 
the tips and anteriorly; caudal with a dark bar at the base 
and a submarginal band which extends to the end of the rays 
on the lower caudal lobe. 
Farlowella acestrichthys Pearson, sp. nov. Plate VIII, fig. 2. 
17009, 3, cotypes, 140-235 mm., Rurrenabaque, Bolivia. Oct., 1921. 
Very closely related to F. smithi Fowler from which it dif- 
fers by possessing a longer and more slender rostrum, fewer 
plates in the middle abdominal series, and by the absence of 
tufts of spines on the sides of the head and rostrum. The 
long slender snout and body have won for it the name of 
needlefish in the Beni. 
Head measured to the hind end of the gill opening 3.8 to 
4.1 ; depth 16 to 17 ; D.I,6 ; A. 1, 5 ; eye in the interorbital 2.75 to 
3.3; width of the head in its length 3.5 to 3.75, depth 5 to 5.8, 
snout 1.1 to 1.2, interorbital 5.2 to 6, dorsal spine 1.6 to 1.8, 
