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Fishery Bulletin 96(1 ), 1998 
ture females (68.6-119 mm) had only partially elon- 
gate ovaries without indications of developing ova. 
Geographic distribution (Fig. 63) A widespread 
tropical species ranging from the larger Caribbean 
Islands such as Cuba, Hispaniola, and Puerto Rico, 
south to Uruguay. In the West Indies, adults and ju- 
veniles have frequently been taken in abundance at 
several localities but appear to be limited to soft silt 
and mud sediments which are more common on the 
larger islands with riverine and estuarine habitats. 
Symphurus tessallatus has been taken at several 
inshore locations in Puerto Rico, Cuba, and Haiti, 
and a large number of adults were collected by the 
RV Oregon on the shelf area southwest of Jamaica 
(Caldwell, 1966). Juveniles have been taken from 
several inshore areas in Jamaica as well. 
Along the continental margin S. tessellatus has 
been frequently captured on muddy bottoms from 
Belize ( 17°12'N) south to Uruguay (ca. 37°S). Absence 
of this species in the Yucatan region may be explained 
by upwelling (Rivas, 1968) or by different sediments 
in this region. The Yucatan Shelf is a broad lime- 
stone plateau with a minimum of land-derived de- 
Figure 63 
Geographic distribution of Symphurus tessellatus based on mate- 
rial examined (discussion of geographic distribution appears in 
species account) 
trital sediments (Harding, 1964;Topp and Hoff, 1972). 
Sediments on the inner shelf off the Yucatan Penin- 
sula are firm, consisting of skeletal remains of vari- 
ous planktonic and benthonic organisms, ooids, cal- 
careous pellets, lithic fragments, and grapestone ag- 
gregates, instead of soft silt and mud typical of more 
southern locations. This dramatic change in sub- 
strates to firmer sediments in the Yucatan region may 
account for the absence of S. tessellatus in the wa- 
ters off southern Mexico. 
Symphurus tessellatus is one of the most abundant 
and frequently collected tonguefish species, especially 
in trawls, from Belize and Honduras south to Ven- 
ezuela and along the entire coastline of northern 
South America from the Guianas to about southern 
Brazil (Meek and Hildebrand, 1928; Cervigon, 1966; 
Palacio, 1974; Carvalho et al., 1968; Menezes and 
Benvegnu, 1976). Menezes and Benvegnu (1976) de- 
scribed S. tessellatus as the most abundant tongue- 
fish collected along the Brazilian coast from about 
26°49'S to 4°S in northern Brazil. South of 28°S, it 
appears to be much rarer, and all specimens I exam- 
ined from Rio Grande do Sul and southwards were 
juveniles. This suggests that adult S. tessellatus are 
not regular components of the ichthyofauna of Uru- 
guay and northern Argentina, but that juveniles ei- 
ther seasonally migrate into, or are passively trans- 
ported into, the waters off Uruguay and northern 
coastal Argentina. Thus it appears that the region 
south of Rio Grande do Sul, which comes under peri- 
odic influence from the cold Falkland Current, does not 
harbor large populations of this essentially tropical 
species so common in warmer waters farther north. 
The specimen from the inner continental shelf of 
Argentina identified by Lazzaro ( 1973) as S. plagiusa 
and listed in the distribution section for S. plagusia 
( -S . tessellatus in the present study) by Menezes and 
Benvegnu ( 1976) is probably not S. tessellatus. From 
the counts and figure provided by Lazzaro, it more 
closely matches S. trewavasae in meristic features 
and general body shape. 
Bathymetric distribution Throughout its range, 
juvenile S. tessellatus are commonly taken by beach 
seine in nearshore habitats, and larger adults are 
frequently captured by trawl in deeper waters. Indi- 
viduals have been collected from depths of 1 to 86 m 
(Table 10). There is an ontogenetic migration off- 
shore. Juveniles occur commonly in medium- to high- 
salinity regions of estuaries and in high-salinity, soft- 
bottom habitats in nearshore mudflats. Adults gen- 
erally range into deeper water, although a few large 
fishes that I examined were taken in relatively shal- 
low water. Most (352/374, 94%) of the S. tessellatus 
examined in this study were collected between 1 and 
