Fundulus caddo, Fast, Hundt, Alley, and Sandel, 2025

Fast, Kayla M., Hundt, Peter J., Alley, Zachariah D. & Sandel, Michael W., 2025, Phylogenomic species delimitation of studfishes (Fundulidae: Fundulus): evidence for cryptic species in agreement with the Central Highlands vicariance hypothesis, Zootaxa 5604 (3), pp. 309-328 : 318-319

publication ID	https://doi.org/10.11646/zootaxa.5604.3.5
publication LSID	lsid:zoobank.org:pub:FB9A879B-49E0-40C8-A93E-830856946991
DOI	https://doi.org/10.5281/zenodo.15047146
persistent identifier	https://treatment.plazi.org/id/03DA87B7-1969-933D-FF20-FA56FEB4F97E
treatment provided by	Plazi
scientific name	Fundulus caddo, Fast, Hundt, Alley, and Sandel
status	sp. nov.

Treatment

Fundulus caddo, Fast, Hundt, Alley, and Sandel , New Species

urn:lsid:zoobank.org:act:5DCE2003-A19E-4325-8C20-062BC0AB5A0F

Ouachita Studfish

Figs. 6–7 View FIGURE 6 View FIGURE 7

Holotype. JFBM 50603 View Materials (1 alc.; female), from JFBM 40428, Caddo River at Caddo Gap, 34.39777, -93.62171, Montgomery Co., Arkansas, U.S.A., 29 May 2002. GoogleMaps

Paratopotype. JFBM 40428 View Materials (43 alc.), Caddo River at Caddo Gap, 34.39777, -93.62171, Montgomery Co., Arkansas, U.S.A., 29 May 2002 GoogleMaps .

Paratypes. JFBM 48545 View Materials (5 alc. 95%), Caddo River at Caddo Gap, gravel bar along County Road 8, just N of County Road 240 , 34.38495, -93.60635, Montgomery Co., Arkansas, U.S.A., 30 April 1999 GoogleMaps . JFBM 30488 View Materials (9 alc.), Ouachita River at U.S. Highway 270, 3.5 miles W of Mt. Ida , 34.61089, -93.69793, Montgomery Co., Arkansas, U.S.A., 30 April 1999 GoogleMaps . JFBM 30406 View Materials (12 alc.), Tenmile Creek at U.S.A. Highway 70, 2 miles E of Nancy , 34.54527, -92.75372, Saline Co., Arkansas, U. S.A., 30 April 1999 GoogleMaps .

UAIC 10065.09 View Materials (56 alc.), Caddo River at Caddo Gap, ca. 0.25 mi off AR Hwy 8, 34.45, -93.7911, Montgomery Co., Arkansas, U.S.A., 27 March 1991 . UAIC 7736.02 View Materials (20 alc.), Caddo River at US Hwy 70 bridge , Gleenwood, 34.3214, -93.5525, Pike Co., Arkansas, U.S.A., 26 July 1984 GoogleMaps .

Diagnosis. Distinguished from other members in the complex as a distinct lineage as determined by molecular phylogenetic and population genomic evidence ( Hundt et al. 2016, this study) and by its limited distribution ( Figure 5B View FIGURE 5 ).

Description. Same as Fundulus catenatus . Meristic characters as follows: dorsal rays 12–16 (modally 14), anal rays 3–17 (modally 15), left pectoral rays 16–18 (modally 17), caudal rays 15–18 (modally 17), lateral scale rows 12–15 (modally 13), lateral scales 40–50 (modally 45) ( Table 1 View TABLE 1 ).

Distribution. This species is native to the Red, Ouachita, and Saline drainages in the Ouachita Highlands.

Etymology. The common name, Ouachita Studfish, refers to the Ouachita Highlands in the United States where the fish is endemic. Fundulus caddo sp. nov. is described from the Caddo River. The specific epithet caddo honors the Caddo Nation who are the descendants of early inhabitants of the Ouachita Highlands. Treated as a noun in apposition.