106 
Fishery Bulletin 96( 1 ), 1998 
Barker, 1993:168 (North Carolina; seasonal distri- 
bution, abundance of larvae at two barrier island 
inlets). Schwartz et al. 1993:108 (North Carolina; 
abundance in dredged canal system at barrier is- 
land). ?Van der Veer et al., 1994:456 (inshore habi- 
tats, Puerto Rico; juvenile occurrence, abundance 
and seasonality of settlement). Barovec, 1995:89 
(distribution on west Florida shelf). Toepfer and 
Fleeger, 1995:242 (Louisiana estuary; diets of ju- 
veniles). Franks et al., 1996:377 (north central Gulf 
of Mexico; prey item of juvenile cobia, Rachycentron 
canadum ). Meyer and Franks, 1996:164 (north 
central Gulf of Mexico; food item of adult cobia, 
Rachycentron canadum). Allen and Baltz 1997:91 
(Barataria Bay, Louisiana; seasonal distribution 
and abundance). 
Symphurus plagusia (not of Schneider, in Bloch and 
Schneider, 1801). Chabanaud, 1939:26 (American 
Atlantic and Gulf coasts). 
ISymphurus plaguisa. Evseenko, 1982:135 (larva in 
Gulf Stream waters off Nova Scotia). 
fVIisidentificatsons Regan, 1914:23 (Brazil; speci- 
mens were S. trewavasae). Chabanaud, 1948b: 134 
(Louisiana; reversed specimen, actually S. civi- 
tatium). Lazzaro, 1973:245 (Argentina; probably S. 
trewavasae). Roux, 1973:176 (Brazil; probably S. 
trewavasae). Lema and Oliveira, 1977:7 (South Bra- 
zil; probably S. trewavasae). ?Guitart, 1978:729 
(Cuba; specimen figured appears to be S. tessellatus). 
Lema et al., 1980 (South Brazil; possibly based on S. 
trewavasae). Gaspar-Billanes and Espinosa-Perez, 
1989:252 (inner continental shelf, Quintana Roo, 
Mexico; actually S. diomedeanus). Seret and 
Andreata, 1992:94 (two specimens from continental 
shelf South Brazil; actually S. ginsburgi). 
Diagnosis Symphurus plagiusa is distinguished 
from all congeners by the combination of predomi- 
nant 1-4-3 IB pattern; 10 caudal-fin rays, 4 hypurals; 
81-91 dorsal-fin rays; 66-75 anal-fin rays; 44-49 
total vertebrae; 76-86 scales in longitudinal series; 
absence of well-developed pupillary operculum (small 
remnant of pupillary operculum may be present); 
unpigmented peritoneum; mostly incomplete row of 
teeth partially covering margin of ocular-side 
dentary; ocular-side premaxilla usually lacking teeth 
altogether (occasionally with few teeth on anterior 
margin of premaxilla); a fleshy ridge on posterior 
region of ocular-side lower jaw; scales present on both 
blind and ocular sides of posterior rays of dorsal and 
anal fins; absence of membrane ostia in dorsal and 
anal fins; ocular surface ranging from uniformly dull 
tannish to dark brown without crossbands to light 
or dark brown with sharply contrasting dark brown 
crossbands but always without pigmented blotch on 
caudal region of ocular surface; blind side without 
pepper-dot pigmentation; usually with a conspicu- 
ous black spot on outer surface of upper angle of 
ocular-side opercle; dorsal, anal, and caudal fins with- 
out conspicuous spots or blotches. 
Description A relatively large species attaining 
maximum lengths of ca. 175 mm SL. IB pattern usu- 
ally 1-4-3 (85/141 specimens), less frequently 1-4-2 
(24/141) or 1-3-3 (22/141), rarely 1-5-2 (Table 2). Cau- 
dal-fin rays usually 10 (132/139), less frequently 9 
or 11 (Table 3). Borsal-fin rays 81-91, usually 84-90 
(Table 4). Anal-fin rays 66-75 (Table 5). Total verte- 
brae 44-49, usually 45-48 (141/143) (Table 6). 
Hypurals 4 (143/143). Longitudinal scale rows 76- 
86 (Table 7). Scale rows on head posterior to lower 
orbit 15-19, usually 17-18 (Table 8). Transverse 
scales 30-39 (Table 9). 
Proportions of morphometric features presented in 
Table 30. Body moderately deep; maximum depth in 
anterior one-third of body; body depth tapering 
gradually posterior to midpoint. Preanal length much 
smaller than body depth. Head moderately long and 
wide, somewhat narrower than body depth. Head 
length shorter than head width (HW:HL 1.07-1.46, 
Table 30 
Morphometries for holotype (LS 124) and 30 other speci- 
mens of Symphurus plagiusa. (Abbreviations defined in 
methods section; SL is expressed in mm; characters 2 to 
14 are expressed in thousandths of SL; 15 to 21 in thou- 
sandths of HL; n = no. of specimens measured.) 
Character 
Holotype 
n 
Range 
Mean 
SD 
1. SL 
122.1 
30 
64.7-171.6 
103.8 
33.72 
2. BD 
322 
30 
283-326 
304.7 
8.89 
3. PDL 
— 
30 
22-51 
38.4 
6.23 
4. PAL 
— 
30 
140-243 
199.7 
27.69 
5. DBL 
— 
30 
933-979 
960.6 
11.82 
6. ABL 
790 
30 
727-826 
787.6 
20.52 
7. PL 
— 
29 
51-79 
67.4 
6.80 
8. PA 
— 
30 
36-75 
54.7 
9.51 
9. CFL 
— 
30 
94-141 
106.6 
9.65 
10. HL 
162 
30 
145-210 
192.5 
13.73 
11. HW 
210 
30 
212-265 
234.9 
14.57 
12. POL 
84 
30 
111-145 
128.9 
7.93 
13. UHL 
115 
30 
147-182 
167.2 
10.01 
14. LHL 
93 
30 
91-123 
102.5 
7.89 
15. POL 
515 
30 
619-842 
671.8 
39.31 
16. SNL 
227 
30 
194-247 
218.2 
16.35 
17. UJL 
242 
30 
180-242 
202.8 
14.83 
18. ED 
101 
30 
83-126 
101.6 
9.81 
19. CD 
136 
30 
213-391 
278.7 
39.81 
20. UHL 
707 
30 
734-1046 
871.8 
78.06 
21. LHL 
571 
30 
436-707 
535.2 
58.15 
