136 FISHES OF WESTERN SOUTH AMERICA 
Genus 48: LEPTODORAS Boulenger 
Leptodoras Boulenger, 1898, Ann. Mag. Nat. Hist., (7), I, 478; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 395; 
Eigenmann, 1925, Trans. Amer. Phil. Soc., X XIT, 356. 
Hemidoras Figenmann and Eigenmann, 1888, Proc. Cal. Acad. Sci., (2), I, 1 
Eigenmann and Eigenmann, 1890, Occ. Papers Cal. Acad. Sci., I 5 
) 
58; 
, 205. 
Type: Oxydoras acipenserinus Giinther 
Peruvian Amazonia to the Guianas 
Nuchal shields with a foramen on each side; maxillary barbel with portion 
beyond the bone divided into an unfringed and outer fringed part; back without 
scutes; slender form, depth 5-9; origin of ventrals forward of the middle point; 
adipose continued forward as a keel, to which the depressed dorsal spine nearly 
attains; mouth large and edentulous; barbels short, the width of the membrane 
uniting the bases of the mental barbels more than half their length, the outer 
mental barbel forked. 
99. LEPTODORAS LINNELLI EKigenmann 
Leptodoras linnelli Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 395 (name only) ; 
Kigenmann, 1912, Mem. Carnegie Mus., V, 191, pl. xvii, fig. 1; pl. xvii, fig. 1; 
Yigenmann, 1925, Trans. Amer. Phil. Soc., XXII, 357, pl. ii, fig. 2; pl. v, figs. 3 and 4; pl. xx, 
fig. 4; pl. xxiv, figs. 3-5; 
Fowler, 1939 (1940), Proc. Acad. Nat. Sci. Phila., XCI, 230. 
Leptodoras acipenserinus (non Giinther), Fisher, 1917, Ann. Carnegie Mus., XI, 422, Maciel and Rio 
Guaporé. 
Hemidoras (Leptodoras) linnelli Steindachner, 1915 (1917), Denksch. KK. Akad. Wiss. Wien, 
XCIII, 79. 
British Guiana and Rio Ucayali 
Fowler’s two specimens, 90 and 154, Contamana, are placed here. 
100. LepropoRAS ACIPENSERINUS (Giinther) 
Oxydoras acipenserinus Giinther, 1868, Proc. Zool. Soc. London, 230, pl. xx, Xeberos; 
Steindachner, 1880 (1882), Denksch. KI. Akad. Wiss. Wien, XLIIT, 8, Xeberos. 
Hemidoras acipenserinus Eigenmann and Eigenmann, 1888, Proc. Cal. Acad. Sei., (2), I, 158; 
Eigenmann and EKigenmann, 1890, Occ. Papers Cal. Acad. Sci., I, 255. 
Leptodoras acipenserinus Boulenger, 1898, Ann. Mag. Nat. Hist., (7), IH, 478; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 395; 
Kigenmann, 1925, Trans. Amer. Phil. Soc., X XII, 358. 
Peruvian Amazon 
15878, 1, 110 mm., Rio Paranapura, Yurimaguas, Allen, November, 1920. 
Family V: Ageneiosidae 
Air bladder much reduced and well enclosed in the bony processes of the 
cervical vertebrae; maxillary barbels only. 
