Munroe: Systematics of western Atlantic Symphurus 
145 
70 m (Table 10), but the majority of captures, and 
the center of abundance for this species, occurs in 
depths between 1 and 50 m (82% of the individuals 
in this study). The deepest captures are for a single 
specimen taken at 86 m and 21 individuals at 73 m. 
The majority of shallow water captures were speci- 
mens smaller than 130 mm. 
Interestingly, Menezes and Benvegnu (1976) re- 
ported that in southern Brazil, <S. tessellatus (identi- 
fied as S. plagusia ) occurs only in shallow water (< 12 
m), although it is known to occur in deeper water in 
northern Brazil. They suggested that the presence 
of S.jenynsi off southern Brazil, which generally oc- 
curs on the continental shelf at depths greater than 
12 m, somehow prevented the occurrence of S. 
tessellatus at these depths. Another explanation for 
the shallow depth distribution of S. tessellatus is that 
it is primarily a tropical species reaching its south- 
ern limit of distribution in southern Brazil south of 
Rio de Janeiro. Its bathymetric distribution in these 
waters may be limited not by competitive interac- 
tion from S.jenynsi, but rather the offshore distribu- 
tion of S. tessellatus may be restricted by cooler wa- 
ter temperatures on the shelf. The appearance of S. 
jenynsi, a temperate water species (Menezes and 
Benvegnu, 1976), in these regions indicates that tem- 
perature may strongly influence the offshore distri- 
bution of S. tessellatus in southern Brazil. 
Throughout its range south to at least Rio de 
Janeiro, juvenile S. tessellatus occur in similar habi- 
tats and are often collected with a complete size range 
of <S. plagusia . In the Caribbean, juvenile S. 
tessellatus are also taken with a complete size range 
of S. caribbeanus . Along the northeastern coast of 
South America from Suriname to eastern Brazil, 
large adults of this species are collected in deeper 
areas with a wide size range of specimens of S. 
oculellus and S. diomedeanus. 
Geographic variation A tropical-temperate cline 
was evident (Table 40) for selected meristic features 
examined in S. tessellatus. Counts of dorsal- and anal- 
fin rays and vertebrae generally increased in speci- 
mens collected from more southern portions of the 
species range. Specimens collected in various regions 
of the northern Caribbean had similar counts of fin 
rays and total vertebrae, whereas values for these 
features were progressively greater in specimens 
taken in the southern Caribbean, off northern Bra- 
zil, and especially off southern Brazil, where high- 
est values for meristic features were recorded. 
Remarks Comments regarding the nomenclatural 
history and synonymy of this species were provided 
in Munroe (1991:269). 
labile 40 
Geographic variation in selected meristic features of 
Symphurus tessellatus. Abbreviations: PR = Puerto Rico; 
CUB = Cuba; JAM = Jamaica; HAI = Haiti; BEL = Belize; 
HON = Honduras; PAN = Panama; COL = Colombia; VEN = 
Venezuela; TRI = Trinidad; GUY = Guyana; SUFG = Sur- 
inam and French Guiana; NBR = Northern Brazil; SBR = 
Southern Brazil; n = no. of specimens measured. 
Character 
Area 
n 
Mean 
Range 
SD 
Dorsal rays 
PR 
28 
96.4 
95-99 
1.17 
CUB 
4 
94.7 
93-97 
2.08 
JAM 
25 
95.9 
93-98 
1.41 
HAI 
23 
94.5 
91-99 
1.93 
BEL 
13 
91.2 
93-98 
1.34 
HON 
27 
95.8 
94-97 
1.05 
PAN 
8 
95.0 
92-97 
1.77 
COL 
10 
95.4 
94-98 
1.26 
VEN 
26 
97.8 
96-101 
1.07 
TRI 
1 
— 
95 
— 
GUY 
29 
98.6 
95-101 
1.47 
SUFG 
13 
99.3 
97-101 
1.18 
NBR 
38 
98.1 
96-102 
1.39 
SBR 
39 
98.4 
95-101 
1.59 
Anal rays 
PR 
28 
80.3 
78-83 
1.21 
CUB 
4 
79.5 
78-81 
1.29 
JAM 
25 
80.0 
77-82 
1.37 
HAI 
23 
78.4 
77-81 
1.47 
BEL 
13 
79.6 
78-82 
1.31 
HON 
27 
79.7 
78-82 
1.14 
PAN 
8 
79.1 
78-80 
0.83 
COL 
10 
79.0 
75-81 
1.70 
VEN 
26 
81.3 
78-85 
1.82 
TRI 
1 
— ■ 
79 
— 
GUY 
29 
82.3 
80-84 
1.12 
SUFG 
13 
82.7 
81-84 
0.95 
NBR 
38 
82.1 
79-84 
1.32 
SBR 
39 
82.3 
78-86 
1.62 
Vertebrae 
PR 
28 
51.2 
50-52 
0.72 
CUB 
4 
50.3 
49-51 
0.96 
JAM 
25 
50.7 
49-52 
0.79 
HAI 
23 
50.4 
48-52 
0.89 
BEL 
13 
50.6 
50-51 
0.51 
HON 
27 
50.7 
50-52 
0.53 
PAN 
8 
50.6 
50-51 
0.52 
COL 
10 
50.6 
50-52 
0.70 
VEN 
26 
51.4 
50-53 
0.86 
TRI 
1 
— 
50 
— 
GUY 
29 
52.1 
51-53 
0.47 
SUFG 
13 
52.3 
51-54 
0.75 
NBR 
38 
51.9 
50-53 
0.80 
SBR 
39 
52.4 
51-54 
0.78 
Comparisons Symphurus tessellatus most closely 
resembles and is completely sympatric throughout 
the Caribbean and warmer waters of the western 
South Atlantic with S. oculellus, S. caribbeanus , and 
S. plagusia. Symphurus tessellatus can readily be 
distinguished from these tonguefishes by features 
