Cordylancistrus pijao, Provenzano & Villa-Navarro, 2017

Provenzano, Francisco & Villa-Navarro, Francisco A., 2017, A new species of the catfish genus Cordylancistrus (Siluriformes, Loricariidae) from the Magdalena River, Tolima, Colombia, Zootaxa 4294 (5), pp. 522-530 : 523-526

Cordylancistrus pijao , new species

Figure 1 , 2 Tables 1, 2

Holotype. CZUT-IC 1292, 114.8 mm SL, Colombia, Departamento de Tolima, Municipio Villarrica, Vereda La Arcadia, Magdalena River basin, Prado River system, Quebrada Aguas Blancas at its mouth in the Cuinde Blanco River , 03°55’29.6”N 74°36’40.8”W, 950 m asl, L.J. García-Melo, 13 November 2004.

Paratypes. All from Colombia. Departamento de Tolima, Magdalena River basin: CZUT-IC 1660, 53.2 mm SL, same data as the holotype . CZUT-IC 1723, 1 C&S, 84.4 mm SL, same data as the holotype . MBUCV-V- 32974, 117.6 mm SL, same data as the holotype. CZUT-IC 3999, 41.3 mm SL, Municipio Mariquita, Vereda Flor Azul, Quebrada Aguasal tributary of the Gualí River , 05°12’26.5”N 74°59’0.3”W, F. A. Villa-Navarro and N. Oviedo, 0 8 April 2010 . CZUT-IC 5174 , 141.0 mm SL, Municipio San Antonio, Vereda Pringamosal, Saldaña River system, Cucuana River , 04°01’32.7”N 75°28’17,4”W, L. J. García-Melo and N. Oviedo, 18 February 2011 . CZUT-IC 7278, 2 ex. 115.9–151.6 mm SL, Municipio San Antonio, Saldaña River system, Cucuana River downstream of the Vereda Florida, 04°02’20.6”N 75°26’29.5”W, 1200 m asl, Y. López Pinto, June 2008 . MBUCV-V- 35677, 122.8 mm SL, Municipio San Antonio, Vereda Florida Baja, Saldaña River system, Cucuana River , Y. López Pinto, 20 July 2008 . MBUCV-V- 35678, 147.5 mm SL, Municipio Roncesvalles, Vereda Pringamosal, Saldaña River system, Cucuana River , under the hanging bridge, 04°01’33.1”N 75°28’17.1”W, Y. López Pinto, 0 1 June 2008 .

Diagnosis. Cordylancistrus pijao n. sp. lacks a unique distinctive character for accurate identification. Between its congeners is distinguished from Cordylancistrus torbesensis by an absence of plates on the ventral border of the snout (vs. ventral border of the snout covered with plates), and by the longest movable odontodes not reaching the pectoral-fin origin (vs. longest movable odontodes extending beyond the pectoral-fin origin); from C. platyrhynchus by the presence of developed and evident evertibles cheek odontodes (vs. odontodes vestigial or almost imperceptible); from C. daguae by having the adpressed dorsal fin not reaching adipose-fin origin (vs. adpressed dorsal fin reaching adipose-fin origin), and by having a greater postdorsal length (26.8%–31.2% SL vs. 34.6%–39.8% SL; see Table 2); from C. nephelion and C. perijae by having a different color pattern: C. pijao has the dorsal and lateral sections of head and body light brown or beige with rounded or elongated dark (black) blotches, sometimes faded or barely visible, without a definite pattern while C. nephelion has the dorsal and lateral sections of the head and body blackish to greenish brown with numerous white irregular spots and C. perijae has the dorsal surface of head and body uniformly brown. It is distinguished from Andeancistrus platycephalus by the absence of spiny keels on the lateral plates of the body (vs. lateral plates with spiny keels); from A. eschwartzae by the snout covered with bony plates, except at the tip (vs. snout completely covered with plates), by a longer posterior body region, narrower body, and shorter dentary (postdorsal length 34.6%–39.8% SL vs. 31.3%–34.9% SL; cleithral width 30.3%–37.7% SL vs. 37.4%–40.8% SL, dentary length 8.4%–10.2% SL vs. 11.6%–12.8% SL; see Table 2); from Transancistrus santarosensis and T. aequinoctiale by the snout covered with bony plates, except at the tip (vs. lateral edges and partial dorsal region of the snout naked).

Description. Morphometric data given in Table 1. Body robust and deep. Caudal peduncle compressed and high. Dorsal profile of body from tip of snout through dorsal-fin origin slightly convex, then gradually descending straight to caudal-fin origin. Ventral profile of body flat and straight. Caudal peduncle with five longitudinal rows of bony plates. Ventral edges of the caudal peduncle slightly angular. Head broad and slightly depressed. In dorsal view, the outline of the head is rounded. Bony plates of body sides without spiny keels. Lateral line bony plates 24– 25. Postanal plates 9-10. Interdorsal plates 4-5, the last with slight keel. Ventral surface of head and abdomen naked to anal-fin origin. Urogenital papilla present, located posterior the anus, shows different shape according sex. Snout covered with small bony plates, except tip, larger specimens have naked strip with odontodes on snout edge. Nostrils juxtaposed and closer to eyes than tip of snout. The anterior nostril easy visible but posterior partially covered with flap of skin. Eyes small, located dorsolaterally. Orbits ringed with very small odontodes. Interorbital space flat or gently convex. Posterior edge of supraoccipital without fleshy keel. Interopercular region with visible rosette of numerous hypertrophied evertible odontodes. Area anterior to hypertrophied cheek odontodes not covered by bone plates. Hypertrophied cheek odontodes straight with curved tip, 27–39, increase in number with size; longest, most posterior hypertrophied odontodes do not reach pectoral-fin origin. Mouth wide. Lip surfaces papillose. Papillae of upper lip slightly larger. Posterior lip edge with evident undulations, border of each undulation irregular. Maxillary barbel very short, almost two thirds of length attached to lower lip by fleshy fold. Distal third of the maxillary barbel free. Premaxilla and dentary very wide, almost of same size. Inside mouth, behind teeth, slight fleshy projections present. Numerous teeth, 64–147 teeth in premaxilla and 82–170 teeth in dentary, increase in number with size; teeth thin and elongated, with curved tips towards inside the mouth. Teeth bicuspid with lobes more or less equal; and shovel-shape like. Cusp of each tooth bright yellow, base white.

All fins are well developed. The fin spines (or first ossified unbranched ray of each fin) and branched rays supporting odontodes, in some cases of appreciable size. Dorsal fin i,8. Depressed dorsal fin does not reach adipose-fin origin. In small specimens, dorsal-fin spinelet visible and covered with small odontodes. In large specimens, spinelet often covered by soft tissue. Anal fin with ii,4. The second unbranched ray of the anal fin is attached to the first, and is slightly longer. Caudal fin i,14,i. Its posterior border is obliquely truncated. Pectoral fin i,6. Pectoral-fin spine reaches one third of pelvic spine length. Pelvic fin i,5. Largest specimen> 150 mm TL, which is among the largest species of Chaetostoma group.

Sexual Dimorphism. In large specimens (> 120.0 mm SL) differences in morphology of urogenital papilla, related to sex easy to observe. In females, urogenital papilla present as small fleshy cylinder with truncate end. In males, urogenital papilla present as small fleshy cone with pointed tip. Nuptial male with developed odontodes on snout edge and on spine and first two or three branched rays of pectoral-fin. These odontodes arranged in longitudinal rows, located on dorsal surface. Longest odontodes on distal end of pectoral spine. Also, spine of pelvic-fin with fleshy fold on posterodorsal surface that runs almost its entire length. First three or four branched rays of pelvic-fin with rows of developed odontodes, very similar to that described for pectoral fin. Females have some developed odontodes on spine and first two or three branched rays of pectoral-fin. Differences of urogenital papilla are permanent, but it is unknown if differences of pectoral and pelvic fins are temporary or permanent.

Color. Dorsal and lateral regions of head and body light brown or beige with irregular dark black blotches, sometimes faded or barely visible, without a definite pattern. In larger specimens, blotches seem organized in irregular longitudinal rows. Belly and ventral regions of head whitish. Surface posterior to anus, with same color as dorsal and lateral areas, but lighter. Ventral region of head and body without spots. All fin rays clear yellowish or brown with dark black bands or stripes. Interradial membranes hyaline. Dorsal-fin with four bands; distal edge of dorsal fin without pigment. Pectoral-fin with five to eight bands. Pelvic-fin with four or five bands. Bands observed on supporting elements of pectoral and pelvic fins visible ventrally. Anal fin with two diffuse bands. Caudal-fin with four to five bands. Distal edge of the caudal-fin translucent. In live specimen, fins have reddish tone ( Fig. 2 ).

Geographical distribution. The localities where the specimens of Co. pijao were captured include: Cuinde Blanco River, a tributary of the Cunday River, which in turn drains to the Prado River, and the Gualí and Cucuana rivers, which drain to the Saldaña River. All localities are within the Magdalena River basin. The first location is on the western slope of the Eastern Cordillera of Colombia and the last two localities are on the eastern slope of the Cordillera Central ( Figure 3 ).

Etymology. The name “ pijao ” is treated as a noon in apposition and refers to the native indigenous people, symbol of the Tolima department, who preferred to die rather than submit to Spanish monarchy.

Ecological notes. The quebrada Aguas Blancas has a gravel and sand bottom, and in the area of its mouth in the Cuide Blanco River has mainly moderate-sized rocks that allow the formation of small backwaters. The average temperature is 18° C, with a slightly basic pH (8.1) and moderate conductivity (192.8 µS). The area is characterized by the presence grazing zones and small coffee farms. The original forests have been felled, and zones at different stages of secondary succession are found. At the stream’s mouth, it is possible to observe some large trees (common name caracolí) and some shrubs.

Figures

FIGURE 1. Cordylancistrus pijao, CZUT-IC 1292, holotype, 114.8 mm SL.

FIGURE 2. Cordylancistrus pijao. Live specimen (Photo by Yesid López-Pinto)

FIGURE 3. Map of Colombia showing the capture localities of Cordylancistrus pijao, black star type locality, yellow stars other localities.