Cordylancistrus tayrona, Ardila, 2017

Ardila, Carlos, 2017, A new species of the catfish genus Cordylancistrus (Siluriformes, Loricariidae) from the Sierra Nevada de Santa Marta, Colombia, Zootaxa 4329 (3), pp. 256-266 : 257-261

Cordylancistrus tayrona new species

( Figure 1–2 Table 1)

Dolichancistrus setosus Ballen & Vari 2012

Holotype. IAvHP 7506 (out MBUCV-V-27935), 78.4 mm SL, Colombia, Departamento Cesar, Magdalena River basin, Sierra Nevada de Santa Marta, Badillo River, tributary of Cesar River, north of Valledupar , approx. 10°12’N, 66°05’W, C. Ardila, 17 March 1997.

Paratypes. All from Colombia. Departamento Cesar, Magdalena River basin: MBUCV-V-27935, 4 ex (3 alcohol, 1 C&S), 38.4–65.3 mm SL, Same data as the holotype . ICNMHN 3290 , 4 ex., 40.4–42.8 mm SL, Quebrada Soria, Tuwy River, tributary of César River , near La Jagua de Ibirico , G. Galvis, 0 1 February 1996 . ICNMHN 1158 , 5 ex., 27.4–72.3 mm SL, west of the Serranía de Perijá, Mahuri river , tributary Cesar river, P. Cala, 13 November 1985 . CIUA 698 , 4 ex., 51.0– 70.8 mm SL, Becerril, Cesar River system, Tucuy River , L. Ochoa, 26 March 2007 . CAR 109, 1 ex., 49.2 mm SL, Sierra Nevada de Santa Marta, Seco River, tributary of César River , north of Valledupar , C. Ardila, 17 March 1997 . CAR 110, 2 ex., 69.9–77.3 mm SL, Sierra de Perijá, Tocaimo River, tributary of César River, north of Agustín Codazzi , C. Ardila, 28 April 1997 . CAR 113 , 1 ex., 54.0 mm SL, Sierra Nevada de Santa Marta, Guatapurí River, tributary of César River , C. Ardila, 10 December 2002. MBUCV-V- 26710, 6 ex (5 alcohol, 1 C&S), 41.9–48.3 mm SL, Sierra Nevada de Santa Marta , Quebrada Los Clavos, tributary of César River , near Pueblo Bello, west of Valledupar , C. Ardila, October 1994. MBUCV-V-26711, 5 ex., 33.3– 46.0 mm SL, Sierra Nevada de Santa Marta , Pontón River , tributary of César River , near Atanquez, C. Ardila, 23 September 1994. MBUCV-V-27910, 3 ex., 20.9–49.9 mm SL, Hurtado River , tributary of César River , R. Royero.

Departamento Magdalena, Caribbean Sea basin: ICNMHN 5750, 7 ex., 41.6–87.4 mm SL, Sierra Nevada de Santa Marta, Quebrada El Congo, tributary of Frio River, Y. López-Pinto, 0 1 February 2002.

Departamento La Guajira, Caribbean Sea basin: ICNMHN 6804, 6 ex., 60.0–96.0 mm SL, Corregimiento Distracción, Ranchería River, Chorreras, J. I. Mojica & C. Castellanos, 0 1 January 2003 . ICNMHN 8891 , 9 ex., 49.0– 62.7 mm SL, Corregimiento Distracción, Ranchería River , Chorreras El Cercado, J. I. Mojica & C. Castellanos, 18 February 2004 . ICNMHN 9775 , 2 ex., 29.1–87.3 mm SL, Corregimiento Distracción, Ranchería River, Chorreras La Virgen , C. Castellanos, 0 4 December 2003 . IAvHP 19 , 5 ex., 29.8–138.8 mm LS, Ranchería River system, 11°33’0”N, 72°36’0”W, M. Bejarano & G. S. R., 11 April 1981 . CAR 106, 1 ex., 48.8 mm SL, Ranchería River , Carlos Ardila, 27 April 1997 . CZUT-IC-7279, 2 ex., 55.2–60.4 mm SL, Municipio de Dibulla, Jerez River , 300 m upstream the bridge on road to Riohacha, 28 September 2011 .

Diagnosis. Cordylancistrus tayrona is distinguished from its congeners by the presence of a unique fleshy black or dark brown keel or excrescence over the posterior tip of supraoccipital. Furthermore, C. tayrona is distinguished from C. torbesensis by the presence of a strip of very small plates (granules) and odontodes along the snout border (vs. border of the snout covered with plates, lacking odontodes). Additionally, C. tayrona can be distinguished from all other species grouped in Andeancistrus , Cordylancistrus , and Transancistrus , except from C. torbesensis and C. daguae , by the presence of elongated movable cheek odontodes, that reach the pectoral-fin origin (vs. short movable cheek odontodes, that do not reach the pectoral-fin origin). Furthermore, C. tayrona is distinguished from all other species of Chaetostoma and Transancistrus , by the presence of odontodes on snout border (vs. snout border naked without odontodes), and from species of Leptoancistrus , by presence of adipose and anal fins (vs. adipose and anal fins absent). Cordylancistrus tayrona resembles the species of Dolichancistrus , but none of the species included in this genus have a fleshy keel on the posterior tip of supraoccipital. The new species lacks any movable cheek odontodes that reach or surpass the midpoint of the pectoral-fin spine length, neither the pectoral-fin spine reach or surpass the distal end of pelvic-fin spine as in Dolichancistrus species.

Description. Morphometric data are given in Table 1. Body slender, depressed anteriorly and slightly compressed posteriorly. Dorsal profile of body from tip of snout to dorsal-fin origin gently convex, straight and sloping downward from dorsal-fin origin to adipose-fin origin, and straight and horizontal to caudal-fin origin. Ventral profile of the body flat and straight. Head wide and depressed. Snout contour semicircular in dorsal view and covered with small plates. Narrow strip of granules (very small plates) present along anteroventral margin of snout. Odontodes over this strip of granules in different stages of development ( Fig. 2 ), at sides larger odontodes are observed and at the center smaller ones. Nuptial males exhibit large odontodes (about as long as eye diameter) over the snout margin.

Nostrils juxtaposed and closer to the eyes than tip of snout. Anterior nostril easily visible but posterior is partially covered with skin flap. Eyes laterodorsal, dorsal edge of orbits flat. Small odontodes surround orbits. Interorbital space narrow and flat. Supraoccipital has an excrescence or fleshy keel, black or dark brown, at occiput that extends slightly posteriorly. In juveniles and some adults specimens, fleshy keel is covered by very thin and transparent layer of skin. Movable, hypertrophied cheek odontodes well developed, numbering 12 to 35. Length of odontodes increase in size posteriorly, longest odontode surpasses the pectoral-fin origin independently of size of specimen ( Fig. 2 ). No plates covering base of movable hypertrophied cheek odontodes anteriorly. Opercular bone with exposed surface conspicuos, with some enlarged odontodes on its distal margin.

Mouth wide and oval. Upper lip edge smooth, not crenulated. Lower lip border crenulated, and each crenulation with other minute undulations. Surface of lips papillose, papillae of anterior lip slightly larger. Maxillary barbels short and free. Upper and lower jaws wide and straight, parallel to each other. Teeth numerous and minute. More than 70 teeth in each premaxillae and dentary. Premaxillary teeth slightly larger than dentary teeth. Teeth villiform and asymmetrically bifid, medial cusp longer and wider than lateral cusp. Medial cusp rounded, lateral cusp pointed. Tooth apex curved toward interior of mouth. Tooth apex yellowish, stalk whitish. Without papillae posterior to premaxillaries and dentaries.

Ventral surface of head and belly naked. Lateral plates are visible posterior to anus, and cover ventral surface of body behind anal-fin. Anal-fin border undulated. Urogenital papillae visible in most specimens, small, located just posterior to the anus, sometimes covered by the anus and not visible. Urogenital papilla acuminate in males, and broad in females.

Lateral line plates 23 to 24. Post-anal plates 10 to 11. Interdorsal plates six, no keeled plates between dorsal and adipose fins. Origin of dorsal fin anterior to pelvic fin origin. Dorsal-fin spinelet present, sometimes covered with tissue and difficult to see. Dorsal fin i,9 (rarely i,8), reaching adipose-fin origin when adpressed. Adipose fin well developed and always present. Adipose-fin spine straight. Pectoral fin i,6. Pectoral-fin spine almost reaching (in smaller specimens) or surpassing half pelvic-fin spine length when adpressed, and longer than longest branched ray. Dorsal and posterior edge of the pectoral-fin spine has one row of perpendicularly enlarged odontodes, better developed in larger specimens. Also in larger specimens, pectoral-fin branched rays with one to three rows of developed odontodes on dorsal surface proximally, most developed in nuptial males. Pelvic fin i,5. Its posterior margin nearly straight, reaching or almost reaching anal-fin origin when adpressed. Third and/or fourth branched pelvic-fin rays longest. Anal fin ii,3. Its posterior margin straight, second ray of anal fin longest. Caudal fin obliquely truncate; lower lobe longer than upper. Caudal fin rays i,14,i. Largest specimens about 115 mm total length, C. tayrona is an intermediately sized species within Cordylancistrus .

Color. Specimens preserved in 70% ethanol show variation of color pattern associated with localities and size. Most common color pattern of the head and dorsolateral surface of the body is overall brown to dark brown with faded whitish spots. Specimens from Ranchería River greenish or pale brown with conspicuos cream spots. In some specimens from Ranchería River, faded spots on sides of head arranged in three or four irregular bands, from near anterior border of snout. In all specimens, abdominal surface is uniformly creamy or whitish. Dorsal-fin spine and branched rays with four to five dark bands, interradial membrane hyaline, except for black spot between bases of spine and first branched ray. Pectoral-fin spine with six to seven dark bands, and branched rays with two to five dark bands. Pelvic-fin spine with four dark bands, and branched rays with two to four dark bands. Interradial membrane of pectoral and pelvic fins hyaline. Anal-fin whitish. Adipose-fin with whitish vertical band. Caudal-fin rays with four to six dark bars or bands, interradial membranes hyaline.

Geographical distribution. Northeastern Colombia, drainages around the Sierra Nevada de Santa Marta and western slope of the Sierra de Perijá, Cesar River system (Magdalena River Basin), Frio River and Ranchería River (Caribbean Sea) Fig. 3 . Additionally, two more localities were found. One locality corresponds to the north of Departamento de Bolivar, Colombia, photos of specimens from this locality were identified, but specimens were not secured nor cataloged. Thus, the locality is considered questionable, but probable. The second locality is Socuy River, Maracaibo Lake Basin, Venezuela. These specimens are cataloged, MBUCV-V-35667, and were donated by a person dedicated to ornamental fish trading, without additional data. Freshwater environments of the Maracaibo Lake Basin are some of the best sampled areas in Venezuela, especially the north region of the basin. Since Schultz (1944) to date no specimens of this species have been collected. These considerations suggest that the occurrence of C. tayrona in the Maracaibo Lake Basin is questionable.

Habitat. Specimens of C. tayrona were collected in piedmont rivers associated with humid tropical areas of the Sierra Nevada de Santa Marta. These rivers have transparent waters, strong to moderate current and temperatures ranging 18–24°C. River substrate materials include rocks, small stones and sand. Aquatic vegetation is scarce or absent, because forest canopy shades most of the river course.

Etymology. The species name, “ tayrona ”, refers to the Tayrona culture or Tayrona nation, an indigenous group that occupied the area of the Sierra Nevada de Santa Marta, and more broadly the area of northeastern Colombia. The name of the species is a homage to these brave and clever people and to their descendants who today live restricted in the Sierra Nevada de Santa Marta. The species name is treated as a noun in apposition.

Figures

FIGURE 1. Cordylancistrus tayrona, IAvHP 7506, 78.4 mm SL. Holotype.

FIGURE 2. Lateral view detail of the head to show the length of movable cheek odontodes and the snout border with granulated band and odontodes. A) Cordylancistrus tayrona, MBUCV-V- 27935, 65.3 mm SL, paratype. B) Cordylancistrus daguae, IMCN- 1285, 88.3 mm SL.

FIGURE 3. Geographic distribution of Cordylancistrus species in Colombia. Cordylancistrus tayrona (triangles, star type locality), Cordylancistrus daguae (square), Cordylancistrus pijao (circles), each symbol may represent more than one lot.