90 
Fishery Bulletin 96( 1 ), 1998 
has a series of nonocellated spots on posterior por- 
tions of dorsal and anal fins. Symphurus ommaspilus 
also possesses ostia in the dorsal- and anal-fin mem- 
branes (absent in S. diomedeanus ) and it has much 
lower, nonoverlapping, meristic features (75-79 dor- 
sal-fin rays vs. 86-96 inS. diomedeanus ; 60-64 anal- 
fin rays vs. 69-80; and 43-44 total vertebrae vs. 47- 
50 in S. diomedeanus). These two species also differ 
with respect to ID pattern (1-4-2 vs. 1-4-3 in S. 
diomedeanus) and S. ommaspilus is much smaller (ca. 
60 mm or less), whereas S. diomedeanus attains 185 
mm or more and does not mature until 90 mm or larger. 
Symphurus ommaspilus is easily diagnosed from 
S. plagiusa, a species that also possesses 10 caudal- 
fin rays and unpigmented peritoneum, because S. 
plagiusa lacks the conspicuous ocellated dorsal- and 
anal-fin spots characteristic of S. ommaspilus. 
Symphurus ommaspilus differs further from that 
species in possessing a pupillary operculum and 
membrane ostia (both absent in S. plagiusa), in lack- 
ing a conspicuous black spot on the outer surface of 
the ocular-side opercle, a fleshy ridge on the ocular- 
side lower jaw, and small ctenoid scales on blind sides 
of dorsal- and anal-fin rays (vs. presence of a black 
opercular spot, fleshy ridge, dark pigmentation on 
isthmus and inner opercular linings, and small scales 
on blind sides of fin rays in S. plagiusa). 
Symphurus ommaspilus differs from the western 
Atlantic S. urospilus in having ocellated spots on the 
dorsal and anal fins and a different caudal-fin ray 
count ( 10 vs. 1 1 caudal-fin rays in S. urospilus). Also, 
S. ommaspilus does not have an ocellated spot on 
the caudal fin, characteristic of S. urospilus. Differ- 
ences between S. om maspilus and other western At- 
lantic tonguefishes with which it might be confused 
are discussed in the “Comparisons” sections under 
species accounts for S. arawak, S. pelicanus, and S. 
kyaropterygium , respectively. 
