Frable et al.: Description of a new species of Synodus in the western Atlantic Ocean 
123 
Scientists have periodically investigated the system- 
atics of synodontids since Linnaeus (1758) described 
Esox synodus in the mid-18th century. Throughout the 
19th century, researchers described 17 Synodus species 
in the western Atlantic (Anderson et al., 1966; Meek, 
1884; Norman, 1935). In the most recent comprehensive 
treatments of western Atlantic lizardfishes (Anderson 
et al., 1966; Russell, 2003), 5 species of Synodus have 
been recognized. Ongoing research to evaluate diver- 
sity of the Caribbean ichthyofauna with DNA barcod- 
ing (Hebert et al., 2003) and traditional morphological 
investigation have led to the recent discovery of many 
new cryptic fish species and the resurrection of several 
formerly synonymized ones in what were thought to be 
well-studied taxa (Baldwin and Weigt, 2012; Baldwin 
et al., 2009, 2011; Tornabene et al., 2010; Victor, 2007, 
2010). In the course of the present work, discrepancies 
were revealed between barcode data and the currently 
accepted species classification of western Atlantic Syn- 
odus lizardfishes. Specifically, each of 2 Synodus spe- 
cies, S. intermedius (Agassiz, 1829) (Sand Diver) and 
S. foetens comprise 2 distinct cytochrome c oxidase I 
(COI) lineages. 
The purpose of this study was to reconcile genetic 
lineages with the nominal species of western Atlantic 
Synodus. Through comparative morphological study, 
our first goal was to determine if the “extra” genetic 
lineages correspond with morphologically distinct spe- 
cies and, if so, to assess whether they represent pre- 
viously synonymized or undescribed species. Herein, 
we resurrect and redescribe Synodus bondi Fowler, 
1939, from the synonymy of S. foetens and describe S. 
macrostigmus as a new species distinct from S. inter- 
medius. We establish neotypes for S. intermedius and 
S. foetens and redescribe both species. We discuss pre- 
liminary evidence of population structure within S. foe- 
tens , S. synodus (Red Lizardfish), Saurida brasiliensis , 
and Trachinoeephalus myops (Snakefish) and species- 
level genetic structure within Synodus poeyi (Offshore 
Lizardfish). Finally, we provide a revised key for the 7 
species of Synodus found in the western Atlantic. 
Materials and methods 
Specimens for genetic analysis were collected in Tobago 
(Trinidad and Tobago), Turks and Caicos Islands, the 
Bahamas, Curasao, Belize, North Carolina, South Caro- 
lina, and Florida. Type material and additional speci- 
mens from other localities were examined from ANSP, 
MCZ, UF, FSBC, KU, and USNM (institutional abbre- 
viations are listed at http://www.asih.org/node/204, ac- 
cessed February 2012). Specimens examined are listed 
in appropriate species sections or in the Appendix. 
Specimens were collected with the use of quinaldine 
sulfate, rotenone, or a pole spear during snorkeling or 
scuba diving, as well as by bottom trawling and hook 
and line fishing. For most specimens, field protocol in- 
volved taking digital photographs of fresh specimens 
to document living color patterns, and subsequently a 
small sample of tissue from the trunk musculature for 
genetic analysis. Voucher specimens were fixed in 10% 
formalin and ultimately preserved in 75% ethanol for 
archival storage. 
Measurements were taken to the nearest 0.1 mm 
with Mitutoyo digital calipers (Mitutoyo Corp., Ja- 
pan 2 ). Measurements and counts follow Hubbs and La- 
gler (1964) and Randall (2009), except as noted below. 
Length of the anterior-nostril flap was measured from 
the posterior tip of the anterior nostril to the distal 
end of the flap when depressed. For the S. intermedius 
group only, the length of the scapular blotch was mea- 
sured on an anterior-posterior axis at its greatest ex- 
panse. For the S. foetens group only, the width of the 
adipose lid was measured as the maximum distance 
between the bony orbit and distal edge of the lid. 
Numbers of vertebrae and dorsal-, anal-, pectoral-, 
and caudal-fin rays were counted from digital radio- 
graphs or preserved specimens. Scales flanking the dor- 
sal- and anal-fin bases are half the size of other trunk 
scales and are reported as half-scales. 
Tissue samples were stored in saturated salt buffer 
(Seutin et al., 1990). DNA was extracted from up to 
approximately 20 mg minced, preserved tissue through 
an automated phenol: chloroform extraction on an Au- 
togenprep965 DNA extraction system (Autogen, Hoi- 
liston, MA) using the mouse tail tissue protocol to a 
final elution volume of 50 pL. In the polymerase chain 
reaction (PCR), 1 pL of extracted DNA was used in a 
10 pL reaction with 0.5 U BioLine (Bioline USA, Inc., 
Boston, MA) Taq polymerase, 0.4 pL 50 mM MgCl 2 , 1 
pL 10x buffer, 0.5 pL 10 mM deoxyribonucleotide tri- 
phosphate, and 0.3 pL 10 pM each primer FISH-BCL 
( 5'TCAAC YAATC AYAAAGATATYGGC AC ) and FISH- 
BCH (5'-TAAACTTCAGGGTGACCAAAAAATCA). The 
PCR theromcycle protocol was: 1 cycle of 5 min at 95°C; 
35 cycles of 30 s at 95°C, 30 s at 52°C, and 45 s at 72°C; 
1 cycle of 5 min at 72°C; and a hold at 10°C. PCR prod- 
ucts were purified with ExoSAP-IT (Affymetrix, Santa 
Clara, CA) with 2 pL 0.2x enzyme and incubated for 30 
min at 37°C. The reaction was then inactivated for 20 
min at 80°C. Sequencing reactions were performed with 
1 pL of this purified PCR product in a 10 pL reaction 
that contained 0.5 pL primer, 1.75 pL BigDye reaction 
buffer (Life Technologies Corp., Carlsbad, CA), and 0.5 
pL BigDye in the thermal cycler for 30 cycles of 30 s 
at 95°C, 30 s at 50°C, 4 min at 60°C, and then were 
held at 10°C after completion of cycles. These sequenc- 
ing reactions were purified with MultiScreen-HV plates 
(MAHVN4550; EMD Millipore Corp., Billerica, MA) ac- 
cording to the manufacturer’s instructions and stored 
dry until analyzed. Sequencing reactions were analyzed 
on an Applied Biosystems 3730XL automated DNA se- 
quencer (Life Technologies Corp.), and sequence trace 
2 Mention of trade names or commercial companies is for iden- 
tification purposes only and does not imply endorsement by 
the National Marine Fisheries Service, NOAA. 
