Frable et al Description of a new species of Synodus in the western Atlantic Ocean 
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76.4% SL (72.2%); preadipose length 75.5-84.5% SL 
(80.2%); dorsal-fin base 13.9-19.4% SL (16.8%), longest 
dorsal-fin ray, usually third, 14.5-20.0% SL (17.0%); 
anal-fin base 12.7-15.9% SL (14.2%), longest anal-fin 
ray, usually second, 7.7-10.7% SL (9.1%); pectoral-fin 
length 12.1-14.0% SL (13.1%); pelvic-fin length 23.1- 
26.7% SL (24.9%); caudal-peduncle length 8.5-19.4% 
SL (14.9%), caudal-fin length (only measured in 19 
specimens because many specimens had damaged cau- 
dal fins) 16.1-22.5% SL (19.4%), ventral caudal lobe 
slightly longer than dorsal lobe. 
Mouth terminal, upper jaw slightly oblique, form- 
ing an 8° angle with the horizontal body axis; upper- 
jaw length 14.7-18.1% SL (16.4%) and 53.9- 64.2% 
HL (60.4%). Teeth needlelike; upper jaw with 2 rows 
of teeth, teeth in inner row longer than teeth in outer 
row; lower jaw with 3 rows of teeth, size of teeth in- 
creasing medially, outer row covered by lips; posterior 
teeth in both jaws directed slightly anteriorly. Palatine 
with 3-4 rows of depressible teeth, teeth directed pos- 
teromedially. Tongue with 5 rows of posteriorly direct- 
ed teeth, largest near anterior tip. Anterior nostril on 
level with median axis of orbit; posterior nostril same 
size and situated slightly dorsal to anterior nostril; an- 
terior nostril with small, spade-shaped flap, length of 
flap when depressed 0. 4-1.0% SL (0.6%) and 1.5-3. 6% 
HL (2.4%); anterior nostril flap does not reach posterior 
nostril (Fig. 2B); posterior nostril without flap. 
Cheek with 6-8 rows of large scales, modally 7; 
opercle with vertical row of 6-8 scales on anterior 
margin and several scales posteriorly; predorsal scales 
extending anteriorly to a position approximately one 
orbit diameter posterior to eye; interorbital region na- 
ked. Dorsal and anal fins each flanked basally by 10-12 
half scales, remainder of dorsal and anal fins without 
scales; large, diamond-shaped scales covering pelvic-fin 
base, remainder of pelvic fin and pectoral fin without 
scales; 5-7 rows of body scales extending onto base of 
caudal fin; upper and lower caudal lobes each with a 
single, enlarged, horizontally elongate scale. 
Coloration 
Before preservation (Fig. 30 Head and dorsal half of 
trunk gray-green to brown, ventral half of trunk pale; 
specimens more than 200 mm SL with 9-13 dark 
brown bars along length of trunk laterally, bars more 
faint in smaller specimens and resemble wide crosses 
that are widest along lateral midline; markings on left 
and right portions of trunk connected to one another 
across dorsal midline to form saddles; trunk with sev- 
eral thin, golden-yellow stripes dorsally, with stripes 
becoming disrupted near lateral midline and forming 
distinct stripes again ventrally; groove above max- 
illa with stripe of black pigment from below anterior 
edge of orbit to posterior end of jaw; posterior edge of 
branchiostegal membrane yellow; scapular region with 
small rectangular black blotch of pigment partially hid- 
den by operculum, length 1.4-3. 3% SL (2.3%) and 5.1- 
12.2%- HL (8.4%); dorsal fin yellow-brown with multiple 
oblique rows of dark pigment; adipose fin brown; pec- 
toral fin translucent with 4-5 diagonal bars of dark 
brown pigment; pelvic fins golden-yellow with darker 
pigment between rays; anal fin yellow; caudal fin light 
brown with 3-5 rows of dark pigmentation spanning 
both lobes, posterior fringes of fin dark brown. 
In preservative (Fig. 3D) Trunk tan to light brown dor- 
sally, pale ventrally; dark markings along trunk pres- 
ent but faded in some specimens; black pigmentation 
on scapular region and jaw easily visible; barring on 
caudal fin less distinct in older specimens; barring on 
dorsal fin faded and pigmentation on pectoral and pel- 
vic fins indistinct. 
Distribution 
Synodus intermedins was described originally from “the 
inlets and river outflows of Brazil” (Agassiz in Spix and 
Agassiz, 1829). The species also occurs widely through- 
out the western Atlantic. Specimens examined in this 
study are from Bermuda, the Gulf of Mexico, and the 
eastern coasts of the United States, Puerto Rico, Saba, 
Leeward Islands, Belize, Venezuela, Colombia, French 
Guiana, Guyana, Brazil, and Trinidad and Tobago (Fig. 
4). Specimens are known from depths up to 183 m, but 
most specimens have been collected at depths <60 m. 
Comparisons of Synodus macrostigmus, 5. intermedius, 
and congeners 
The anterior-nostril flap in S. macrostigmus is signifi- 
cantly larger (2.7- 4.9% HL, mean 3.8%) than that flap 
of S. intermedius (1. 5-3.6%- HL, mean 2.4%) and tapers 
distally (ends more abruptly in S. intermedius — Fig. 2, 
A and B). Synodus macrostigmus on average possesses 
a larger orbit diameter (20.8% versus 17.2% HL) and 
more narrow interorbital (width 13.8% versus 15.9% 
HL). It possesses a more blunt snout than does S. inter- 
medius (Fig. 3, A-D) and has fewer lateral-line scales 
(45-48, modally 47, versus 49-52, modally 51, in S. in- 
termedius) (Table 3). Dark pigment on the caudal fin 
in S. macrostigmus is restricted primarily to the cen- 
ter of the fin and ventral lobe, whereas S. intermedius 
has a distinctive banded pattern with 3 to 6 bars. The 
scapular blotch in S. macrostigmus is much larger and 
more ovoid than the miniscule, rectangular marking in 
S. intermedius, mean length of blotch 16.4%- HL in S. 
macrostigmus and 8.4% HL in S. intermedius. 
Additional fresh specimens of the new species are 
needed to verify differences in color patterns, but, in 
available material, S. macrostigmus has orange lateral 
stripes and markings on the trunk and S. intermedi- 
us has yellow stripes (Fig. 3, A and C). Specimens of 
S. intermedius more than 200 mm SL also appear to 
have more vertical bars along the trunk (9-13) than 
do large specimens of S. macrostigmus (6-8). Finally, 
S. macrostigmus has not been collected at depths shal- 
