136 BULLEITIN 189, UNITEt> STATES NATIONAL MUSEUM 



anterior nostril in more or less of a tube, on edge of snout; posterior 

 nostril a slit in upper lip; gill opening a slit before and below pectoral; 

 no scales; lateral line present; dorsal long, low, its origin over or more 

 usually behind gill opening, ending a short distance in front of tip of 

 tail. 



Five species have been recognized in the collections studied. Accord- 

 ing to the report of the Mission (1943, p. 288) the species of this genus 

 are of limited commercial importance in Peru. Landings were reported 

 from Talara, Negritos, and Paita. 



KEY TO THE SPECIES 



a. Body with large black spots on back and at least on upper part of side. 



b. Teeth in two series in each jaw; tail notably longer than head and trunk; 



pectoral fin much longer than snout, 2.7 to 3.0 in head. 



c. Head large, 8.9 in total length; eye about half length of snout, 10.5 in head; 



no papilla on upper lip between nostrils; inner row of teeth in lower jaw 



discontinued posterior to about midlength of jaw.- triserialis (p. 136) 



cc. Head smaller, 9.7 in total length; eye nearly as long as snout, 6.3 in head; 



a prominent papilla on upper lip between nostrils; inner row of teeth 



complete grandimaculata (p. 138) 



bb. Teeth in two series in upper jaw, in a single series in lower jaw; tail scarcely 

 longer than head and body; pectoral fin about as long as snout, 6.7 in 



head afuerae, new species (p. 139) 



aa. Body not spotted with black, plain or with small pale dots. 



d. Head large, depressed, broader than deep at posterior angle of mouth, 6.9 

 to 7.4 in total length, 2.9 to 3.1 in length anterior to vent; teeth in lower 

 jaw in two complete series, sometimes with a few small teeth in a third 



series pacifici (p. 141) 



dd. Head smaller, compressed, somewhat deeper than broad at posterior angle 

 of mouth, 7.5 to 8.5 in total length, 3.1 to 3.4 in length anterior to vent; 

 teeth in lower jaw in two series anteriorly, the inner series discontinued 

 posterior to about midlength of jaw callaensis (p. 142) 



OPHICHTHUS TRISERIALIS (Kaup) 



Muraenops triserialis Kaup, 1856a, p. 12, "Pacific" (original description). 



Ophisurus calif orniensis Garrett, 1863, p. 66, Baja California (original descrip- 

 tion). 



Ophichthus rugifer Jordan and Bollman, 1890, p. 155, Charles Island, Galdpagos 

 (original description; compared with O. triserialis) . 



Ophichthus triserialis Meek and Hildebrand, 1923, p. 155 (synonymy; descrip- 

 tion). 



Body moderately robust, subcylindrical; head and trunk notably 

 shorter than tail, length anterior to vent 2.4 in total length; head 

 somewhat deeper than broad at posterior angle of mouth, its length 

 anterior to gill opening 8.9 in total length, 3.7 in length anterior to 

 vent; depth 7.5 in length anterior to vent, 1.95 in head; snout rather 

 short, moderately blunt, extending beyond mandible a distance about 

 equal to pupil, 4.9 in head; eye small, lateral, 10.5 in head, 2.15 in 

 snout; mouth moderate, the gape reaching far beyond eye, 2.5 in 

 head; teeth quite small, some apparently worn down, others broken 



