Dolichancistrus fuesslii
Creators: name: Ballen, Gustavo A.
name: Vari, Richard P.
Publisher: name: Zenodo
Year: 2012
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Actinopterygii
Siluriformes
Loricariidae
Dolichancistrus
Dolichancistrus fuesslii

description: Dolichancistrus fuesslii (Steindachner, 1911) Fig. 5
Ancistrus füsslii Steindachner, 1911: 373 [type locality: Ostkolumbien, Sosomoco, 800 m Höhe (= Eastern Colombia, Sosomoco, 800 m elevation; see under Remarks concerning type locality information)].
Pseudancistrus pediculatus Eigenmann, 1917: 679 [type locality: Colombia, río Negro Villavicencio]. - Eigenmann, 1922: 78, 224; fig. 17, pl. 10, fig. 4, pl. 12, fig. 3 [in part, Colombia, Villavicencio, Barrigón, Tengavita; record from río San Juan basin of western Colombia questionable, see Remarks]. - Henn, 1928: 85 [type depository]. - Fowler, 1942: 132 [Colombia, río Meta; not citations of species from río San Juan and río Tamana]. - Gosline, 1945: 90 [in checklist]. - Ibarra & Stewart, 1987: 70 [type depository].
Lasiancistrus fuesslii Isbrücker, 1980: 44 [correction of diacritic mark in specific epithet; shift to Lasiancistrus].
Dolichancistrus pediculatus Isbrücker, 1980: 48 [shift to Dolichancistrus]. - Isbrücker, 2001: 27 [in listing of species of the Loricariidae]. - Isbrücker, 2002: 27 [in listing of species of the Loricariidae]. - Burgess, 1989: 434 [in listing of species of Loricariidae]. - Fisch-Muller, 2003: 384 [in checklist of species of Ancistrinae]. - Lasso et al. 2004a: 173 [río Orinoco basin]. - Armbruster, 2004a: 48, fig. 38 [phylogenetic systematics of Loricariidae]. - Lasso et al., 2004b: 131 [río Meta basin]. - Maldonado-Ocampo et al., 2005: 154, map 146 [in part; Andes of Colombia, río Negro at Villavicencio; summary data]. - Ferraris, 2007: 235 [in checklist of catfishes]. - Maldonado-Ocampo et al., 2008: 198 [Colombia]. - Urbano-Bonilla et al., 2009: 160 [Colombia, Departamento de Casanare].
Dolichancistrus fuesslii Isbrücker, 2001: 27 [shift to Dolichancistrus]. - Isbrücker, 2002: 27 [in listing of species of the Loricariidae]. - Fisch-Muller, 2003: 384 [in checklist of species of Ancistrinae]. - Maldonado-Ocampo et al., 2005: 154, map 146 [Andes of Colombia; Sosomoco (= Meta, Quebrada Susumuco; correction of misspelling and elaboration of originally cited type locality; see Remarks); summary data and translation of original description of A. fuesslii Steindachner]. - Ferraris, 2007: 235 [in checklist of catfishes]. - Maldonado-Ocampo, 2008: 198 [Colombia].
Material examined. All collections from Colombia. CAS 58789 (formerly IU 13928), paratypes of Pseudancistrus pediculatus, 7, 5, 47.94-80.95 mm SL, Departamento de Meta, Villavicencio, quebrada Gramalote. CAS 58790 (formerly IU 13665), 3, 2, 32.9- 38.3 mm SL, Departamento de Meta, Villavicencio, quebrada Gramalote. CAS 58795 (formerly IU 13945), 6, 19.1-32.7 mm SL, Departamento de Meta, Villavicencio, quebrada Sumico (= Susumuco). CAS 58799 (formerly IU 13939), 5, 12.7-43.5 mm SL, Departamento de Cundinamarca, Quetame, río Contador. CAS 58820 (formerly IU 13929), paratypes of Pseudancistrus pediculatus, 2, 59.7-72.1 mm SL, Departamento de Meta, Puerto Porfía, Barrigona. CZUT-IC 3327, 1, 63.5 mm SL, Departamento de Boyacá, San Luis de Gaceno, vereda Calichama, quebrada El Chopal, tributary of río Lengupa. CZUT-IC 3346, 1, 47.3 mm SL, Sabanalarga, Vereda San Joaquín, quebrada La Raya, tributary of río Upía. CZUT-IC 5491, 13, 21.6-63.9 mm SL, Departamento de Casanare, quebrada Agua Blanca. FMNH 40217, 1, 95.3 mm SL, Departamento de Meta, Villavicencio. FMNH 58562, 6, 12.8-22.7 mm SL, Departamento de Cundinamarca, Quetame, río Contador. FMNH 58563, 21, 13.4-43.2 mm SL, Departamento de Meta, Villavicencio, quebrada Blanca. FMNH 58566, 17, 2 cs, 22.5-67.4 mm SL, Departamento de Meta, Villavicencio. IAvH-P 3939, 7, 42.2-85.3 mm SL, Departamento de Boyacá, río Jenesano. IAvH-P 3940, 16, 40.6-103.1 mm SL, Departamento de Boyacá, río Orinoco drainage, río Meta basin, without exact locality data. IAvH-P 7931, 22, 16.8-33.3 mm SL, Departamento de Meta, Villavicencio, Quebrada Susumuco, at mouth into río Negro. IAvH-P 9230, 22, 58.6-97.0 mm SL, Departamento de Casanare, Aguazul, Aguazul-Sogamoso road, quebrada Chichaca IAvH-P 9605, 7, 63.5-124.4 mm SL, Departamento de Casanare, Aguazul, Aguazul-Sogamoso road, quebrada Chichaca. IAvH-P 11381, 9, 25.8-105.8 mm SL, Departamento de Boyacá, río Orinoco drainage, río Meta basin, without exact locality data. ICNMHN 1177, 1, 97.9 mm SL, Departamento de Meta, Acacías, Acacías-Guamal road, unnamed tributary of río Acacías. ICNMHN 1196, 2, 57.9-85.5 mm SL, Departamento de Meta, Acacías, río Acacías, río Playón, 500 masl. ICNMHN 1474, 14, 33.0 - 80.3 mm SL, Departamento de Cundinamarca, Cáqueza, río Negro, río Cáqueza. ICNMHN 1475, 10, 29.8-62.5 mm SL, Departamento de Cundinamarca, Cáqueza, río Saname. ICNMHN 2638, 11, 35.7-95.1 mm SL, Departamento de Casanare, Aguazul, quebrada Costa Grande near retén de Guadalcanal, 860 masl. ICNMHN 2650, 5, 62.4-96.5 mm SL, Departamento de Casanare, Aguazul, quebrada Costa Grande, 860 masl. ICNMHN 2817, 7, 60.8-93.3 mm SL, Yopal, quebrada Costa Grande, near Pajarito (Boyacá), 800 masl. ICNMHN 2839, 1, 66.0 mm SL, Departamento de Boyacá, San Luis de Gaceno, quebrada La Quinchalera. ICNMHN 3212, 12, 22.3-80.9 mm SL, Departamento de Boyacá, Santa María, río Batá, road to Chivor. ICNMHN 3385, 1, 62.6 mm SL, Departamento de Meta, Guamal, caño Camelia. ICNMHN 3560, 2, 37.0- 49.3 mm SL, Departamento de Meta, Serranía de La Macarena, río Duda, río Guape between Cruce Oriente and quebrada Uribe. ICNMHN 3641, 6, 45.2-64.8 mm SL, Departamento de Meta, Acacías, río Acacías, caño Acacías. ICNMHN 7945, 26, 22.7-90.0 mm SL, Departamento de Boyacá, Pajarito, río Cusiana. ICNMHN 7979, 2, 40.0- 69.2 mm SL, Colombia, no specific locality data. ICNMHN 7993, 3, 33.7-62.9 mm SL, ICNMHN catalog data citing collection locality as near Leticia incorrect; see Ballen (2011) for further details. ICNMHN 7996, 12, 32.6-72.7 mm SL, Colombia, no specific locality data. ICNMHN 8003, 1, 56.1 mm SL, Departamento de Meta, Cumaral, caño Pecuca, quebrada Piedras Negras. ICNMHN 13198, 1, 53.6 mm SL, Departamento de Meta, Cumaral, río Guacavia, caño Pecuca. ICNMHN 14582, 30, 56.5-117.0 mm SL, Departamento de Boyacá, Santa María, río Garagoa basin. ICNMHN 15337, 1, 62.3 mm SL, female, Colombia, no specific locality data. ICNMHN 15338, 1, 74.7 mm SL, female, Colombia, no specific locality data. ICNMHN 15339, 1, 81.6 mm SL, female, Colombia, no specific locality data. ICNMHN 15340, 1, 84.1 mm SL, male, Colombia, no specific locality data. ICNMHN 16811, 4, 85.2-101.8 mm SL, Departamento de Boyacá, Jenesano, río Garagoa, 2100 masl. ICNMHN 17504 (formerly CAR 294), 1, 68.9 mm SL, Departamento de Boyacá, río Jenesano. MLS 538, 1, 102.9 mm SL, Departamento de Boyacá, Guaicaramo. MLS 545, 2, 85.8-100.7 mm SL, Colombia, no specific locality data. MLS 549, 1, 76.4 mm SL, Departamento de Meta, Villavicencio. MLS 746, 4, 19.2-93.8 mm SL, Monterralo, Yopal-Sogamoso road 15 km before Pajarito, quebrada Mesiana, tributary of quebrada Guacharaca. MLS 796, 1, 54.7 mm SL, Departamento de Cundinamarca, Tibirita, río Machetá, 1500 masl. NMW 48026, 1 (97.7 mm SL; holotype of Ancistrus fuesslii), Colombia: Ostkolumbien, Sosomoco, 800 m Höhe” (= eastern Colombia, Sosomoco, 800 m in elevation; see comments under Remarks concerning type locality). NRM 15171, 1, 47.9 mm SL, Departamento de Meta, Villavicencio, Buenavista, unnamed tributary of río Negro, NRM 30168, 1, 60.3 mm SL, Departamento de Cundinamarca, Quetame, río Contador. USNM 100786, 1, 78.9 mm SL, Departamento de Boyacá, Guaicaramo. NMW 48026, 1 (97.7 mm SL; holotype of Ancistrus fuesslii), Colombia: Ostkolumbien, Sosomoco, 800 m Höhe” (= eastern Colombia, Sosomoco, 800 m in elevation; see comments under Remarks concerning type locality).
Diagnosis. Dolichancistrus fuesslii is distinguished from all congeners in the form of the distal margin of the pelvic fin in mature males (margin of the fin distinctly W-shaped, with the longer lateralmost unbranched ray followed by a second ray that is distinctly shorter laterally and with the medial portion of the second ray and the third ray progressively longer than the first ray and followed by the progressively shorter fourth and fifth rays vs. the margin of the pelvic fin straight to approximately smoothly convex, respectively). Dolichancistrus fuesslii is further separable from congeners in the relative position of the anteromedial margin of the posterior cheek plate with respect to the anterior margin of the exposed portion of opercle (anterior margin of posterior check plate in contact with anterior margin of the exposed portion of opercle when cheek apparatus adpressed vs. posterior cheek plate distinctly separated from anterior margin of exposed opercle). Dolichancistrus fuesslii can be further differentiated from D. atratoensis in the relative size and shape of the cheek plates (the two plates of approximately the same length and rectangular in shape, vs. the anterior plate approximately one-half the length of the posterior plate and triangular, respectively), the relative length of the pectoral-fin spine in mature males (spine reaching posteriorly far beyond the posterior tip of the adpressed pelvic fin vs. only reaching midway along the length of the pelvic fin, respectively). Dolichancistrus fuesslii can be further separated from D. carnegiei in the relative shape of the cheek plates (both cheek plates rectangular, vs. square, respectively) and coloration pattern (presence of lateral dark blotches vs. diffuse marbling on lateral portions of body, respectively). Dolichancistrus fuesslii further differs from D. cobrensis in the condition of the buccal papilla within the oral cavity at the posterior limit of the premaxillary symphysis (a papilla present vs. absent, respectively) and the pattern of distribution of the hypertrophied odontodes along the margin of the snout in mature males (odontodes extensive and continuously distributed along the entire anterior and anterolateral margins of the snout, vs. odontodes restricted to the anterolateral corners of snout, respectively).
Description. See description under generic account for features common to all species of Dolichancistrus. Largest examined specimen 124.4 mm SL. Morphometrics and meristics presented in Table 1. Dorsal-fin rays ii,7 to 9; anal-fin rays ii,2 or 3; caudal-fin rays i,14,i [i,12,i in one aberrant individual]; pectoral-fin rays i,6; pelvic-fin rays i,5. Preadipose plates 2 or 3; median plates 24 or 25. Buccal papilla present within oral cavity at symphysis of premaxillae. Enlarged odontodes present along entire anterolateral and anterior margins of snout and on median region of snout anterior to nares. Odontodes along snout margin terminate posteriorly distinctly short of anterior margin of cheek plates. Anterior margin of posterior cheek plate in contact with anterior exposed margin of opercle. Anterior and posterior cheek plates rectangular and approximately of same size. Hypertrophied cheek odontodes distally recurved. Distal margin of pelvic fin in mature males W-shaped with longer first ray followed by shorter lateral branch of second ray and then increasingly longer medial branch of second ray and all of third ray and then progressively shorter fourth and fifth rays. Spine of adpressed pectoral fin of mature males surpassing tip of adpressed pelvic-fin spine. Adpressed pectoral-fin spine of mature females reaching posteriorly to within area from mid-length of adpressed pelvic fin to the tip of pelvic fin. Odontodes on dorsal surface of pectoral-fin spine extending over distal one-half of spine in mature males.
Coloration in alcohol. Overall ground coloration of head and body brownish on lateral and dorsal surfaces, lightly colored ventrally other than for brown upper lip. Body in juveniles and smaller individuals with five or six distinct midlateral dark spots ranging from slightly anterior of vertical through dorsal-fin origin to caudal peduncle. Midlateral series of dark spots less obvious in larger individuals. Some overall darker individuals with midlateral pigmentation barely apparent. Specimens collected from higher elevation locations sometimes lack discrete marks along sides of body, showing instead diffuse longitudinal stripe in that region. Dorsal surface of body with four saddle-like marks; marks more obvious in smaller individuals. First mark located under anterior portion of dorsal fin, second under base of posterior dorsal-fin rays, third between dorsal and adipose fins, and fourth immediately behind posterior terminus of adipose fin. Third and fourth marks continuous across dorsal midline. Saddle-like marks obscured in specimens with dark gray overall coloration. Dorsal fin with alternating variably separated dark and light areas along rays that form irregular bar-like pattern along length of fin. Dorsal-fin membranes lack dark pigmentation. Anal fin in most examined specimens lacks dark pigmentation, but some barring or spots present in samples from higher elevations. Caudal fin with alternating dark and light areas along rays that form irregular transverse bar-like pattern across vertical extent of fin. Pectoral-fin spine with alternating dark and light regions on dorsal surface but dark pigmentation absent from ventral surface. Pectoral-fin rays in smaller individuals without dark pigmentation; larger specimens with alternating dark and light pigment pattern on lateral rays, but with medial rays unpigmented. Pelvic-fin spine with alternating dark and light areas along length; pattern more obvious in larger individuals. Pelvic-fin rays with some irregular darker areas but distinct barring pattern on rays in smaller individuals and distinct barring in larger specimens.
Sexual dimorphism. The pelvic-fin margin in Dolichancistrus fuesslii is sexually dimorphic, being distinctly W-shaped in mature males versus broadly convex in mature females and immatures. Odontodes along the snout margin are more highly developed in mature males than in mature females.
Distribution. Dolichancistrus fuesslii occurs from the northern portion of the Serranía de La Macarena, Departamento do Meta north to Yopal, Departamento do Casanare, Colombia, at approximately 450 to 2100 masl. All records are from upland tributaries in the río Duda and río Meta basins along the eastern flank of the Cordillera Oriental in the río Orinoco system (Fig. 2). Samples of the species in ICNMHN supposedly from Leticia, Departamento de Amazonas, Colombia, likely have incorrect locality information as is the case with the other lots of various species discussed by Ballen (2011: 394).
Remarks. Steindachner (1911: 373) cited the type locality of Ancistrus fuesslii as Ostkolumbien, Sosomoco, 800 m Höhe (= eastern Colombia, Sosomoco, 800 m elevation), without information on the collector. The collector apparently was A. H. Fassl who also sampled lepidopterans during 1911 at that location in the east of the Departamento de Meta, Colombia (Holzinger & Brown, 1982: 26; Salazar-E., 2008: 148). The species name (füsslii) appears to be a printer’s lapsus for the collector’s name (Fassl) since Steindachner applied the correct patronymic to a species of Trichomycterus (Pygidium fasslii, Ferraris, 2007: 418). Sosomoco is an apparent incorrect citation of quebrada Susumuco in the east of the Departamento de Meta with that stream running through the adjoining Departamento de Cundinamarca to the río Negro upstream of Villavicencio (Maldonado-Ocampo et al., 2005: 154; Salazar-E., 2008: 148). The location cited as Sumico (CAS 58795) in the material examined may also be an erroneous citation of Susumuco.
Type localities for Ancistrus fuesslii and Pseudancistrus pediculatus lie very close to each other in the same basin in the western reaches of the río Orinoco. Examination of the type series of both nominal species supplemented by an extensive series of other specimens in that area failed to reveal differences between the nominal forms and we place Pseudancistrus pediculatus as a subjective junior synonym of Ancistrus fuesslii (the Dolichancistrus fuesslii of this study).
Eigenmann was apparently unaware of Steindachner’s (1911) description of Ancistrus füsslii, a species he neither cited in his account of Pseudancistrus pediculatus (1917) nor in his monographic study of the fishes of northwestern South America (Eigenmann, 1922). This oversight was universal until Isbrücker’s (1980: 44) assignment of the species to Lasiancistrus.
Eigenmann (1922: 79) reported Pseudancistrus pediculatus (= Dolichancistrus fuesslii herein) from the Pacific versant rio Tamaná, a drainage distant from the known range of the species east of the Andes. Examination of the specimen (CAS 58792; formerly IU 13655) confirms it is an immature Dolichancistrus and possibly D. fuesslii. The only species of the genus known from rivers of the Pacific slope is D. atratoensis which, however, differs from the Eigenmann specimen in multiple details. This raises the question of erroneous locality information for the specimen, a possibility noted by Eigenmann (1922: 79). The specimen was acquired by Eigenmann from “Mr. W. F. H. Rosenberg” who collected at a numerous localities in northwestern South America. The secondary nature of the information increases the possibility that the locality data is incorrect.
description: Published as part of Ballen, Gustavo A. & Vari, Richard P., 2012, Review of the Andean armored catfishes of the genus Dolichancistrus Isbrücker (Siluriformes: Loricariidae), pp. 499-518 in Neotropical Ichthyology 10 (3) on pages 513-516, DOI: 10.1590/S1679-62252012000300003, http://zenodo.org/record/10476379