158 FISHES OF WESTERN SOUTH AMERICA 
118. PAREIODON MICROPS Kner 
Pareiodon microps Kner, 1855, Sitzb. KK. Akad. Wiss. Wien, XVII, 160; 
Cope, 1871, Proce. Acad. Nat. Sei. Phila., X XIII, 290, Ambyiacu; 
Eigenmann and Eigenmann, 1890, Occ. Papers Cal. Acad. Sci., I, 346; 
Eigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, III, 401; 
Eigenmann, 1918, Mem. Carnegie Mus., VII, 344. 
Trichomycterus pusillus Castelnau, 1855, Anim. Amér. Sud, Poiss., 50, pl. xxiv, fig. 4, Amazon, 
Araguay. 
Rio Ambyiacu to the Araguay 
Subfamily: STEGOPHILINAE 
A group of Pygidiudae lacking mental and nasal barbels and with two maxillary 
barbels, the lower pair very small; mouth inferior and wide, with numerous rows of 
regular teeth; opercle and interopercle spinous, but pectorals soft-rayed; anal short; 
many species capable of some degree of parasitism. 
Genus 57: HENONEMUS Ejigenmann and Ward 
Henonemus Eigenmann and Ward, 1907, Ann. Carnegie Mus., IV, 118; 
Jigenmann, 1918, Mem. Carnegie Mus., VII, 345. 
Type: Stegophilus intermedius EKigenmann and Eigenmann 
Amazons and La Plata 
Originally separated on the basis of the lack of a second maxillary barbel, later 
discovered, but minute. The genus retained on the ground of the negligible size 
of this barbel and the presence of but two opercular spines. 
Teeth numerous on jaws and lips; mandibulars transverse and united; 
separated from Stegophilus chiefly in having the caudal emarginate and in the 
reduced number of opercular spines; second maxillary barbel extremely small. 
119. HeNoNEMUs PUNCTATUS (Boulenger) 
Stegophilus punctatus Boulenger, 1887, Proc. Zool. Soc. London, 279, pl. xxi, fig. 4, Canelos. 
Henonemus punctatus Kigenmann, 1910, Rept. Princeton Univ. Exped. Patagonia, IIT, 401; 
Eigenmann, 1918, Mem. Carnegie Mus., VII, 346, text figs. 23 and 24. 
Canelos, Ecuador; Santarem; Rio Madeira 
15499, 3, 70-88 mm., Rio Morona, Allen, October, 1920. 
15707, 1, Rio Huallaga, Yurimaguas, Allen, November, 1920. 
15708, 2, 65 and 70 mm., Gosulimacocha, Rio Morona, Allen, October, 1920. 
120. HENONEMUS MACROPS (Steindachner) 
Stegophilus macrops Steindachner, 1882 (1883), Denksch. KK. Akad. Wiss. Wien, XLVI, pl. vi, 
figs. 2 and 2a, Lake Manacapurt; 
Kigenmann and Higenmann, 1889, Proc. Cal. Acad. Sci., (2), I, 55; 
BKigenmann and Eigenmann, 1890, Occ. Papers Cal. Acad. Sci., I, 344; 
Higenmann and Higenmann, 1891, Proc. U.S. Nat. Mus., XIV, 37. 
