Ariopsis canteri, Marceniuk, Alexandre P., Acero, Arturo, Cooke, Richard & Betancur-R, Ricardo, 2017

Marceniuk, Alexandre P., Acero, Arturo, Cooke, Richard & Betancur-R, Ricardo, 2017, Taxonomic revision of the New World genus Ariopsis Gill (Siluriformes: Ariidae), with description of two new species, Zootaxa 4290 (1), pp. 1-42 : 9-14

Ariopsis canteri , new species Acero P., Betancur-R. & Marceniuk

New Granada Sea Catfish (English)

Chivo cabezón (Spanish)

Figures 6 and 7 , Tables 2–4 and 6.

Ariopsis bonillai (non Miles), Dahl, 1971: 48–49; Taylor & Menezes, 1978; Acero P. et al., 2002: 60–63; Acero P., 2003: 839. Hexanematichthys bonillai (non Miles), Marceniuk & Ferraris, 2003.

Sciades bonillai (non Miles), Marceniuk & Menezes, 2007.

Ariopsis sp. Betancur-R et al., 2012; Robertson et al., 2015; Acero P. et al. 2017: 73–76.

Material examined. Holotype. INV PEC 5332 (male, 225 mm SL), Colombia, Magdalena, Ciénaga Grande de Santa Marta, Pueblo Viejo , fisherfolk (10° 47' 8.7" N, 74° 24' 58.3" W) . Paratypes. INV PEC 276 (5, 185– 259 mm SL) Colombia, Magdalena, Ciénaga Grande de Santa Marta, Boca Río Sevilla , hook (10° 52' 30.2" N, 74° 24' 53.6" W) ; INV PEC 529 (1, 41 mm SL) Colombia, Magdalena, Ciénaga Grande de Santa Marta, Pueblo Viejo (10° 47' 8.7" N, 74° 24' 58.3" W) ; INV PEC 782 (4, 125– 306 mm SL) Colombia, Magdalena, Ciénaga Grande de Santa Marta, Boca Río Sevilla (10° 52' 30.2" N, 74° 24' 53.6" W) ; INV PEC 895 (5, 45– 82 mm SL) Colombia, Magdalena, Ciénaga Grande de Santa Marta, Cabaña Palmira (10° 52' 30.2" N, 74° 24' 53.6" W) ; INV PEC 1356 (2, 45– 48 mm SL) Colombia, Magdalena, Ciénaga Grande de Santa Marta, Boca de la Barra , west shore (10° 52' 30.2" N, 74° 24' 53.6" W) ; INV PEC 1756 (2, 104– 261 mm SL) Colombia, Magdalena, Ciénaga Grande de Santa Marta, Caño Grande and Río Fundación (10° 52' 30.2" N, 74° 24' 53.6" W) ; INV PEC 2294 (2, 68– 73 mm SL), Colombia, Magdalena, Ciénaga Grande de Santa Marta, Boca Río Fundación (10° 43' 54.2" N, 74° 25' 44.7" W) ; INV PEC 3651 (1, 155 mm SL) Colombia, Córdoba, close to Bahía Cispata (9° 24' 36.4" N, 75° 46' 41.3" W) ; INV PEC 5945 (1, 117 mm SL) Colombia, La Guajira, Uribia, Bahía Portete (12° 8' 53.3" N, 71° 58' 1.1" W) ; INV PEC 8169 (1, 149 mm SL), Colombia, Córdoba, San Antero, Ciénaga Ostional (9° 24' 18" N, 75° 52' 53" W) ; INV PEC 9010 (1, 227 mm SL) Colombia, Magdalena, Ciénaga Grande de Santa Marta, collected with the Holotype, Pueblo Viejo , fisherfolk (10° 47' 8.7" N, 74° 24' 58.3" W) ; INV PEC 9086 (23, 142– 357 mm SL), Colombia, Magdalena, Ciénaga Grande de Santa Marta, Pueblo Viejo (10° 47' 8.7" N, 74° 24' 58.3" W) ; USNM 286488 (2, 220– 248 mm SL), Colombia, Bolívar, Cartagena, among mangroves at La Boquilla ; USNM 292999 (3, 207– 215 mm SL), Colombia, Magdalena, Ciénaga Grande de Santa Marta, east side near SE end of highway bridge.

Diagnosis. Ariopsis canteri can be differentiated from its congeners as follows: from A. assimilis , from Mexico (Quintana Roo) to Honduras (Caribbean), by having 36–44 gill rakers on the first and second gill arches, rarely 37 or 36 (vs. 31–36, rarely 37); from A. felis , from Massachusetts ( US) to Yucatán (Caribbean), by the presence of 36–44 gill rakers on the first and second gill arches (vs. 29–32), lateral margin of sphenotic straight, as wide anteriorly as medially (vs. notched laterally, narrower medially than anteriorly, Figs. 3 and 7 ), pterotic lateral margin markedly convex, sometimes angled (vs. smoothly convex, Figs. 3 and 7 ); from A. gilberti , from Mexico (EP), by the absence of an osseous medial groove (vs. present; Figs. 3 and 7 ), lateral margin of sphenotic straight, as wide anteriorly as medially (vs. notched laterally, narrower medially than anteriorly, Figs. 3 and 7 ); from A. guatemalensis , from Mexico to Costa Rica (EP), by its narrower median portion of mesethmoid (vs. wide, Fig. 3 ), mesethmoid medial notch narrow and deep (vs. large and shallow, Fig. 3 ); from A. jimenezi , from Archipiélago de las Perlas in Panama (EP), by the absence of an osseous medial groove (vs. present; Figs. 3 and 7 ), fleshy medial groove of neurocranium conspicuous or inconspicuous, but never surpassing posterior margin of eyes (vs. conspicuous and very long, always surpassing the posterior margin of eyes, Figs. 4 and 7 ), lateral margin of sphenotic straight, as wide anteriorly as medially (vs. notched laterally, narrower medially than anteriorly, Figs. 3 and 7 ), external posterior branch of lateral ethmoid columnar and thin (vs. depressed and thick, Fig. 3 ), fenestra delimited by mesethmoid and lateral ethmoid conspicuous (vs. inconspicuous, Fig. 3 ), lateral margin of pterotic markedly convex, sometimes angled (vs. smoothly convex, Figs. 3 and 7 ); from A. seemanni , from El Salvador to Panama (EP), by the absence of an osseous medial groove (vs. present; Figs. 3 and 7 ); from A. simonsi , from Colombia to Peru (EP), by the absence of an osseous medial groove (vs. present; Figs. 3 and 7 ), lateral margin of sphenotic notched, narrower medially than anteriorly (vs. straight, as wide medially as anteriorly, Figs. 3 and 7 ).

Description. Morphometrics and meristics summarized in Tables 2–4, 6. Head moderately long, wide and high, especially depressed at lateral ethmoid and frontal area, profile elevated posteriorly, convex from mesethmoid to frontal and straight on parietosupraoccipital. Snout rounded and moderately long. Anterior nostril rounded, with fleshy edge, posterior nostril covered by flap of skin, moderately distant to one another and moderately distant to orbit, not connected by fleshy furrow. Eye lateral, relatively large. Eyes widely separated. Three pairs of long teretiform barbels; maxillary barbel surpassing or not membranous portion of operculum, lateral and mesial mental barbel not reaching posterior margin of gill membrane. Osseous bridge formed by lateral ethmoid and frontal moderately long and slender, delimiting a fenestra little evident under the skin. Cephalic shield exposed, moderately long and wide on supracleithrum, lateral ethmoid and frontal areas, with thick granulation forming distinct patterns from eyes to parietosupraoccipital process. Fleshy portion of dorsomedial groove of neurocranium, affixed to anterior cranial fontanel, evident, reaching or not reaching eyes. Sphenotic straight laterally, as wide medially as anteriorly. Pterotic lateral margin markedly convex, sometimes angled. Parietosupraoccipital slightly keeled, triangular, with straight lateral margins converging posteriorly, relatively short and moderately wide posteriorly, with posterior margin convex. Nuchal plate crescent-shaped, conspicuously granulated dorsally, moderately long and narrow. Mouth subterminal, moderately large, with lips moderately thick and lower jaw arched. Vomerine tooth plates rounded. One pair of accessory tooth plates ovate, with sharp teeth. Premaxilla rectangular transversally, moderately long and wide, with sharp teeth. Dentary with eyebrow-shaped patch of teeth, separated at midline with sharp teeth. Gill membranes fused, attached to isthmus. Sixteen to 20 acicular gill rakers on first arch, 17–24 spike-shaped gill rakers on second arch, rakers present on posterior margin of all gill arches.

Body significantly wider than its height at pectoral girdle area, progressively compressed from pectoral to caudal peduncle, ventrally flattened from pectoral girdle to anal origin. Lateral line sloping ventrally on anterior one-third, extending posteriorly to caudal peduncle, bending abruptly onto dorsal lobe of caudal. Dorsal spine relatively short and thick, shorter than pectoral spine; anterior margin granulated on basal two-thirds, with weak serrations on distal third; posterior margin smooth on basal third, distal third with weak serrations. Seven dorsal-fin soft rays. Pectoral spine moderately long and thick; two-thirds of anterior margin weakly granulated, with weak serrations on distal third; posterior margin straight on basal one-fourth, distal three-fourths with conspicuous serrations. Nine to 11 pectoral soft rays. Posterior process of cleithrum triangular, smooth to rugose, slightly visible. Pelvic-fin deep and large at base, with six rays and well-developed fleshy protuberances in adult females. Adipose fin low; its base moderately long but shorter than the anal-fin base. Anal fin short and moderately long at base, with 18 to 22 rays and ventral profile almost straight. Caudal peduncle moderately high. Caudal fin forked, dorsal and ventral lobes relatively short; dorsal lobe somewhat longer than ventral lobe, posteriorly pointed.

Maximum length: Grows to 460 mm TL.

Coloration in alcohol. Head and body dark brown to bluish above, whitish below; dorsal surfaces of pelvic fin proximally black, distally lighter; anal fin dark, distal tips lighter; caudal grayish to blackish ( Figs. 6 ).

Sexual dimorphism. Only females have well developed fleshy protuberances or pads in basal portion of the pelvic fins, especially during the reproductive season. Vomerine tooth patches ovate to square in females, and reduced and transversally elongated in males. In females, accessory tooth patches larger and ovate, while relatively smaller and elongated in males ( Fig. 8 ).

Distribution and habitat. Endemic to the Caribbean coast of Colombia in the WA ( Fig. 5 ). Found in costal marine and brackish waters; sometimes entering freswaters (e.g., Atrato, Sinú, Magdalena, and Ranchería rivers).

Molecular evidence and phylogenetic relationships. The Caribbean endemic Ariopsis canteri is the sister species of the EP A. seemanni ( Fig. 9 ). This biogeographic pattern suggests that divergence of these species involved a transithmian vicariant event (Betancur-R. et al., 2007, 2012; Betancur-R., 2009).

Etymology. Named after Diego Canter Ríos (1984–2007), a young and talented Colombian ichthyologist who died in a car accident near Santa Marta, along with three other biologists. Species delimitation in Ariopsis was part of Diego’s B.Sc. thesis in Marine Biology, which he could not complete due to his untimely death. Diego collected most of the morphometric and meristic data for the new species and for Ariopsis simonsi .

Remarks. Description of Ariopsis canteri n. sp. contributes to the alpha taxonomy of New World Ariidae , providing formal scientific recognition of a species endemic to the Colombian Caribbean, which has been recognized as endangered (see Acero P. et al., 2016, 2017). See Introduction about misidentification of the New Granada Sea Catfish with Galeichthys bonillai Miles, 1945 , a freshwater ariid in the genus Notarius Gill, 1863 (Acero P. & Betancur-R., 2006).

Figures

FIGURE 3. Neurocranium, dorsal view. A. Ariopsis guatemalensis, STRI 5.2.13.3.; B. A. felis, catfishesbone. acnatsci. org; C. A. canteri, uncataloged; D. A. seemanni, STRI 5.1.1.19.; E. A. jimenezi, STRI no registry; F. A. simonsi, STRI 5.1. 1.10. Abbreviation: LEepb, external posterior branch of Lateral Ethmoid; PT, Pterotic; MS, Mesethmoid; MSmn, Mesethmoid medial notch; mg, medial groove of cranium; SH, Sphenotic.

FIGURE 4. Medial groove of neurocranium. A. Ariopsis felis and B. A. assimilis. White, anterior fleshy portion (apposed to the anterior cranial fontanel); gray, posterior bony portion (formed by the mesial depression of the frontals and the anterior portion of parietosupraoccipital).

FIGURE 5. Sampling localities of examined material.

FIGURE 6. Body in lateral view. Ariopsis canteri, Holotype INV PEC 5332.

FIGURE 7. Head in dorsal view. Ariopsis canteri, Holotype INV PEC 5332.

FIGURE 8. Premaxilla, vomerine and accessory tooth plates in female (A) and male (B), INV PEC, uncataloged specimens.

FIGURE 9. A, Clade including the genera Sciades + Potamarius + Ariopsis, extracted from the Ariidae tree of Betancur-R. et al. (2012), including five of the eight species of Ariopsis validated herein. The complete time tree was estimated using a Bayesian analysis of five mitochondrial and six nuclear gene fragments and 19 calibration points (both inside and outside Ariidae). B, Rooted RAxML phylogram with expanded specimen sampling for six species of Ariopsis, but based on the analysis of only two mitochondrial genes (Cyt b and ATPase 8 / 6; 1937 bp). Nodal numbers indicate RAxML bootstrap support values and posterior probability values (MrBayes tree), respectively. The RAxML and MrBayes trees are identical with respect to topology and highly similar with respect to branch lengths. Two letter country codes follow ISO- 3166.