Dolichancistrus carnegiei ( Eigenmann, 1916 )

Ballen, Gustavo A. & Vari, Richard P., 2012, Review of the Andean armored catfishes of the genus Dolichancistrus Isbrücker (Siluriformes: Loricariidae), Neotropical Ichthyology 10 (3), pp. 499-518 : 508-510

Dolichancistrus carnegiei ( Eigenmann, 1916)

Fig. 3

Pseudancistrus carnegiei Eigenmann, 1916: 85 [type locality: Colombia, Santander, río San Gil = río Fonce, see under Remarks]. - Eigenmann, 1922: 79, fig., 18, pl., 10, fig. 3 [ Colombia, río Guaduas, río San Gil, quebrada de Honda, quebrada de la Pelada, río Baipé]. - Henn, 1928: 85 [type despository]. - Fowler, 1942: 132 [ Colombia, río Magdalena and río Guaduas]. - Gosline, 1945: 90 [in checklist of Neotropical catfishes]. - Miles, 1947: 108 [ Colombia, río Magdalena, Santander and Boyacá]. - Dahl, 1971: 85, fig. [ Colombia, Santander and Boyacá in rivers and quebradas of Cordillera Oriental; maximum size; economic importance]. - Ibarra & Stewart, 1987: 70 [type depository].

Lasiancistrus carnegiei Isbrücker, 1980: 43 [shift to Lasiancistrus].

Dolichancistrus carnegiei Isbrücker, 2001: 26 [shift to Dolichancistrus]. - Fisch-Muller, 2003: 384 [in checklist of species of the Ancistrinae ]. - Maldonado-Ocampo et al., 2005: 153, map 144 [Andes of Colombia, río San Gil; summary data]. - Mojica et al., 2006: 33 [ Colombia, middle río Magdalena]. - Ferraris, 2007: 235 [in checklist of catfishes]. - Maldonado-Ocampo et al., 2008: 198 [in checklist of fishes of Colombia].

Material examined . All collections from Colombia. CAS 56749 (formerly IU 13926 ), 2, 89.0- 126.4 mm SL, Departamento de Boyacá, río Baipe . CAS 77345 (formerly IU 13662 ), 4, paratypes, 14.7-23.4 mm SL, Departamento de Santander, Socorro, río Honda (= quebrada Honda) . FMNH 58559 (formerly CM 7579 a), 1, 24.4 mm SL, Departamento de Santander, quebrada La Pelada (location undetermined) . IAvH-P 3936 , 3 , 38.6-123.7 mm SL, Departamento de Boyacá, río Magdalena drainage, without exact locality data . IAvH-P 3937 , 1, 109.1 mm SL, Departamento de Boyacá, Villa de Leyva, río Suárez . IAvH-P 3938 , 1 , 44.8 mm SL, Departamento de Boyacá, Villa de Leyva, río Suárez . IAvH-P 4329 , 2 , 43.1-44.3 mm SL, Departamento de Santander, Floridablanca, río Lebrija, río Frío . IAvH-P 4330 , 14 , 29.3-49.7 mm SL, Departamento de Santander, Piedecuesta, río Chicamocha, río Manco . IAvH-P 4332 , 25 , 22.0- 92.5 mm SL, Departamento de Santander, Piedecuesta, río Chicamocha, río Manco . IAvH-P 5263 , 21 , 31.6-152.6 mm SL, Departamento de Boyacá, Iguaque, río Iguaque, Pozo de La Vieja . IAvH-P 8563 , 4 , 37.6-104.8 mm SL, Departamento de Boyacá, Santa Sofía, río Moniquirá at Paso del Ángel . IAvH-P 10733 , 6 , 61.2 -101.0 mm SL, Departamento de Boyacá, río Cane above Pozo de La Vieja . IAvH-P 10734 , 33 , 27.4-152.1 mm SL, Departamento de Boyacá, río Cane-Iguaque , valle Escondido . IAvH-P 11382 , 2 , 73.8 -93.0 mm SL, Departamento de Boyacá, río Magdalena drainage, without exact locality data . ICNMHN 591 , 16 , 35.5-96.3 mm SL, Departamento de Santander, Simacota, quebrada Santa Rosa, tributary of río Suárez . ICNMHN 1822 , 2 , 104.4 -121.0 mm SL, Departamento de Boyacá, Togüí, finca Versalles, río Ubaza . ICNMHN 3235 , 6 , 36.9-68.1 mm SL, Departamento de Santander, Charalá, corregimiento de Virolín . ICNMHN 5371 , 5 , 48.0- 84.8 mm SL, Departamento de Santander, Simacota-Chima road, quebrada Guamacá . ICNMHN 5445 , 9 , 47.7 -117.0 mm SL, Departamento de Boyacá, río Suárez, río Sáchica . ICNMHN 15328 , 1 , 85.6 mm SL (female), Without exact locality data . ICNMHN 15329 , 1 , 85.9 mm SL (female), Without exact locality data . ICNMHN 15330 , 1 , 80.9 mm SL (female), Without exact locality data . ICNMHN 15331 , 1 , 77.9 mm SL (female), Without exact locality data . ICNMHN 15332 , 1 , 72.5 mm SL (female), Without exact locality data . ICNMHN 15333 , 1 , 89.9 mm SL (female), Without exact locality data . ICNMHN 15334 , 1, 103.6 mm SL (female), Without exact locality data . ICNMHN 15335 , 1 , 76.8 mm SL (female), Without exact locality data . ICNMHN 15336 , 1 , 81.9 mm SL (female), Without exact locality data . ICNMHN 16016 , 7 , 21.9-54.4 mm SL, Departamento de Santander, El Playón, río Lebrija , quebrada La Naranjera . ICNMHN 16017 , 1 , 42.8 mm SL, Departamento de Santander, El Playón, río Lebrija , quebrada La Naranjera . ICNMHN 16018 , 3 , 22.8-46.5 mm SL, Departamento de Santander, El Playón, río Lebrija , quebrada La Naranjera . ICNMHN 17498 , 3 , 48.6-106.8 mm SL, Departamento de Boyacá, río Suárez, río Sáchica . ICNMHN 17500 , 6 , 76.2-127.4 mm SL, Without exact locality data . ICNMHN 17501 , 42 , 59.36-120.58 mm SL, 4 cs, Departamento de Santander, Bucaramanga, río Tona . ICNMHN 17505 , 3 , formerly CAR 102, 76.7- 61.2 mm SL, Departamento de Santander, Floridablanca, río Lebrija, río Frío . MLS 522 , 11 , (43.6-129.4 mm SL), Departamento de Boyacá, Santa Rosa de Viterbo, río Arriba . MLS 542 , 1, 120.2 mm SL, Departamento de Boyacá, Santa Rosa de Viterbo, río Arriba . MLS 543 , 6 , 61.9-89.4 mm SL, Departamento de Santander, San Gil . MLS 550 , 1 , 63.5 mm SL, Departamento de Santander, San Gil .

Diagnosis. Dolichancistrus carnegiei can be separated from all congeners in the size and form of the cheek plates (plates externally of approximately the same size and nearly square from lateral view with the anterior margin of posterior cheek plate not reaching to the anterior margin of exposed opercle vs. the anterior plate longitudinally shorter than the posterior plate in D. atratoensis or both plates about the same size but rectangular in D. cobrensis and D. fuesslii ). Dolichancistrus carnegiei is further distinguished from D. atratoensis in the length of the adpressed pectoral-fin spine in mature males (extending to the tip of the adpressed pelvic fin vs. extending only midway down the length of the adpressed pelvic fin, respectively) and in the distance from the base of the anal-fin spine to the tip of the fin (at least one-half vs. at most one-third of the length of the pelvic-fin spine, respectively). Dolichancistrus carnegiei additionally differs from D. cobrensis in the condition of the buccal papilla within the oral cavity at the limit of the symphysis of the premaxillae (present vs. absent, respectively) and the pattern of development of the enlarged odontodes along the margin of the snout in mature males (odontodes present along the entire anterior and anterolateral margins of the snout vs. limited to the lateral margins of the snout, respectively). Dolichancistrus carnegiei is further distinguished from D. fuesslii in the form of the distal margin of the pelvic fin in mature males (smoothly convex vs. W-shaped, respectively).

Description. See description under generic account for features general for Dolichancistrus . Largest examined specimen 153.7 mm SL. Morphometrics presented in Table 1 . Dorsal-fin rays ii,8 or 9; anal-fin rays ii,2 or 3; caudal-fin rays i,14,i; pectoral-fin rays i,6; pelvic-fin rays i,5. Preadipose plates 2 or 3; median plates 24 to 26. Buccal papilla present within oral cavity at limit of symphysis of premaxillae. Enlarged odontodes present along entire anterior and anterolateral margins of snout in mature males. Odontodes along lateral margin of snout terminate distinctly short of anterior margin of cheek plates. Anterior margin of posterior cheek plate distinctly separated from anterior margin of exposed portion of opercle. Anterior and posterior cheek plates of approximately same length; square in lateral view. Hypertrophied cheek odontodes recurved distally. Distal margin of pelvic fin straight in juveniles and smoothly convex in mature specimens. Adpressed pectoral-fin spine reaching posteriorly to area between middle and tip of adpressed pelvic fin in mature males and to middle of pelvic-fin spine in mature females. Odontodes extending over distal one-third of dorsal surface of pectoral-fin spine. Caudal-fin margin oblique to slightly emarginate.

Coloration in alcohol. Overall ground coloration of head and body brownish on lateral and dorsal surfaces, lightly pigmented ventrally other than for brown upper lip. Longitudinal dark lateral stripe evident in juveniles and sometimes in adults. Dorsolateral region of body in juveniles with some more lightly colored patches, particularly in area underneath dorsal fin but with clear patches barely evident in some adults. Largest examined individual with nearly uniform dark coloration on head and body. Dorsal fin with alternating dark and light areas along rays; pigmentation forms irregular oblique stripe-like pattern along length of fin. Spacing between dark marks on rays variable, but individual dark areas always distinct. Dorsal-fin membranes typically unpigmented, but pigmentation patches overlying rays extend onto adjacent membranes in some individuals. Anal fin with dark pigmentation in form of transverse bands or single diffuse spot. Caudal fin with alternating dark and light areas along rays; pigmentation forms irregular transverse bar-like pattern across vertical extent of fin. Pectoral-fin spine with alternating dark and light stripes along dorsal surface and ventral surface unpigmented. Largest examined specimen with dorsal surface of spine nearly uniformly dark. Pectoral-fin rays with alternating dark and light areas forming stripe-like transverse pattern. Pelvic-fin spine with alternating dark and light areas along dorsal surface; pattern more obvious in larger individuals. Pelvic-fin rays with some irregular darker areas on rays in smaller individuals, but with diffuse barring pattern in larger specimens.

Sexual dimorphism. Mature males of Dolichancistrus carnegiei have odontodes along the margin of the snout very slightly more developed than in mature females or dimorphism in this feature is absent. Mature males have proportionally longer pectoral-fin spines than mature females. Distribution. Dolichancistrus carnegiei occurs in eastern tributaries of the middle portion of the río Magdalena basin along the Cordillera Oriental in the departments of Boyacá and Santander, Colombia ( Fig. 2 ).

Remarks. Eigenmann (1916) reported the type locality for Dolichancistrus carnegiei as the río San Gil; however, the official name for this river in the municipality of San Gil, Santander was changed to río Fonce early in the twentieth century (R. Caicedo, pers. comm.). Dahl (1971: 85) reported that Dolichancistrus carnegiei (his Pseudancistrus carnegiei ) grows to approximately 20 cm (SL?). Both Miles (1947: 108) and Dahl (1971: 85) noted that the species was exploited for food and was of some economic importance.

Specimens of Dolichancistrus carnegiei from Boyacá, Colombia (IAvH-P 5263, 10733, 10735) vary in the degree of fin development and some individuals have foreshortened pectoral, pelvic, caudal, and anal fins albeit without any obvious pattern to these reductions. These individuals also differ in the pigmentation of the lateral surface of the body, most prominently in the presence of unpigmented regions. This variation likely represents populational anomalies. Samples with definitive locality data show D. carnegiei and D. fuesslii to be allopatrically distributed; however, these species are commingled a few ICNMHN and IAvH-P lots. These series were collected along potential trans-cordilleran oil pipeline routes spanning the distribution of the two species and likely represent intermingled samples collected to both sides of the Cordillera Oriental.

Figures

Fig. 3. Dolichancistrus carnegiei, CAS 56749, 126.4 mm SL. Colombia, Departamento de Boyacá, río Baipé: dorsal, lateral and ventral views.

Fig. 2. Map of Colombia showing localities for the species of Dolichancistrus. Dotted contours represent 1000 masl isoclines and striped areas indicate regions above 3000 masl. Some symbols represent more than one locality and/or lot of specimens. Dolichancistrus atratoensis (triangles; type locality = 1); D. carnegiei (squares; type locality = 2); D. cobrensis (circles; type locality = 3); D. fuesslii (inverted triangles; type locality = 4). Base map provided by John D. Lynch.