Lasiancistrus guacharote (Valenciennes, 1840)

Armbruster, Jonathan W., 2005, The loricariid catfish genus Lasiancistrus (Siluriformes) with descriptions of two new species, Neotropical Ichthyology 3 (4), pp. 549-569 : 555-557

Lasiancistrus guacharote (Valenciennes, 1840) Fig. 5

Hypostomus guacharote Valenciennes , in Cuvier & Valenciennes, 1840: 508. Puerto Rico [locality in error, see comments].

Ancistrus mystacinus Kner, 1854: 276 . Caracas, Venezuela [locality in error, see comments].

Lasiancistrus maracaiboensis Schultz, 1944: 314 . Río Socuy, 3 km above its mouth, Venezuela.

Material Examined. Venezuela. Zulia, lago Maracaibo drainage : AUM 22136, 1 , 80.1 mm SL, caño El Padre (tributary of río Onia - río Escalante ) on road from Hwy 2 to town of KM 35 , 8.76161°N, 071.76314°W, 19 Dec 1999 . INHS 60465 , 2 c&s, río Yasa, río Palmar basin, 5 km S Machiques on road to Tucoco, 9 Jan 1991 . MNHN A- 9567, 1, 84.7 mm SL, holotype of L. guacharote , locality given as Porto Rico, but most likely from the lago Maracaibo basin of Venezuela, see comments . NMW 44200, 1 , 65.6 mm SL, holotype of L. mystacinus , locality given as Caracas, but this is likely a mistake, see comments . UF 30724 , 3 , 42.2 -69.0 mm SL, río Palmar on Route 6 (Maracaibo-Machiques road) at Hacienda Mucuras, 14 Mar 1981 . UF 30744 , 3 , 55.9--65.1 mm SL, río Araquaisa at Route 6 bridge (Machiques-La Fria), 14 Mar 1981 . USNM 121038 , 1, 119.5 mm SL, holotype of L. maracaiboensis , río Socuy 3 km above mouth, 24 Feb 1942 . USNM 121048 , 2 , 26.6-90.7 mm SL, paratypes of L. maracaiboensis , río Motatan 4 km above Motatan, 25 Mar 1942 . USNM 121050 , 2 , 23.3-89.5 mm SL, paratypes of L. maracaiboensis , río San Pedro tributary of río Motatan ) at bridge, 20 Mar 1942 . USNM 121049 , 7 , 64.5-107.4 mm SL, paratypes of L. maracaiboensis , río Socuy 3 km above mouth, 24 Mar 1942 . Merida, lago Maracaibo drainage: INHS 59866 , 4 c&s, río Escalante at highway 1 bridge, 7 Jan 1991 . UF 30779 , 12 , 67.9 -89.0 mm SL, río Chama just N of El Vigia on the road to Merida, 15 Mar 1981 . Tachira, lago Maracaibo drainage: UF 30768 , 6 , 55.8 -68.0 mm SL, río Orope at bridge between La Fria and La Honda, at km marker 817, 15 Mar 1981 . UF 25472 , 3 , 57.4-81.1 mm SL, Municipality Alberto Adriani, 25 May 1977 . Colombia, Meta, ANSP 128695 , 0, río Orinoco drainage (probably introduced, see Comments): río Negro just downstream from main Villavicencio-Puerto Lopez highway at La Balsa, E side of river, 4°4’N, 73°4’W, 3 Jan 1972 .

Diagnosis. Lasiancistrus guacharote can be separated from all other species of Lasiancistrus except for some L. schomburgkii by having a single to a small patch of platelets ventromedially from the insertion of the pectoral-fin spine ( Fig. 5 ) and nowhere else ventrally, and from L. schomburgkii by having black spots in the dorsal fin (vs. no or white spots) and black bands in the paired and caudal fins (vs. bands absent).

Description. See genus description for more information. Morphometrics in Table 1. Largest specimen 119.5 mm SL. Abdomen naked. 23-25 (mode = 24) plates in median series. 4- 24 whiskerlike odontodes in evertible cheek mass (mode = 16, N = 26); 17-43 (mode = 25, N = 26) total hypertrophied odontodes in cheek mass.

Color. Small, white spots on head, fading on nape. Body mottled with faint hint of dorsal saddles. Abdomen light tan, ventral surface of caudal peduncle slightly darker. Dorsal fin with large, rectangular spots centered and darkest on fin rays, almost combing to form bands. Paired, caudal, and anal fins with narrow bands. Lower half of caudal fin slightly darker than upper. Adipose fin uniformly dark. Color darkens with size.

Sexual dimorphism. Nuptial males with whiskerlike odontodes at the anterolateral corner of the snout, else as in genus description.

Range. The Lago Maracaibo basin of Venezuela and Colombia ( Fig. 3 ).

Comments: The holotype of Lasiancistrus guacharote is said to be from Puerto Rico (Cuvier & Valenciennes, 1840), but it is highly unlikely that loricariids could have arrived naturally on this northern Caribbean island. The holotype was collected by Augus Plée, a young adventurer-naturalist who collected fish specimens from around the Caribbean and the Gulf of Mexico in the 1820’s, and who did collect in Puerto Rico ( Pietsch, 1995). Plée also collected in the Maracaibo basin of Venezuela. Specimens of upland fishes that are known to be sympatric with Lasiancistrus such as Parodon Valenciennes, 1850 and Piabucina Valenciennes, 1850 were collected by Plée in the Maracaibo basin according to the MNHN catalog on the internet. Examination of the type reveals that it has the characteristic used to diagnose the species from the Maracaibo Basin. In all likelihood, the locality was somehow misplaced. Plée was not around to correct the error because he died on the day he was to return to France ( Pietsch, 1995).

Lasiancistrus mystacinus was described by Kner (1854) based on a single specimen with the stated locality of “Caracas”. The drainage in Caracas is the río Tuy, and no Lasiancistrus have been reported from the Tuy. It is believed that the locality “Caracas” in Kner’s work simply means where the specimens left Venezuela (R. P. Vari, pers. comm.), and that these specimens could have come from anywhere in Venezuela. The type of L. mystacinus has the plates only in the corners of the pectoral girdle as is used to diagnose L. guacharote and is considered a synonym. The only other species of Lasiancistrus in Venezuela is L. tentaculatus , which lacks plates on the abdomen and L. schomburgkii , which has more plates on the abdomen.

Lastly, Schultz (1944) described Lasiancistrus maracaiboensis as the first species of Lasiancistrus in Venezuela with an accurate type locality. These specimens also have a small patch of platelets near the insertion of the pectoral-fin spine. Kner (1854) and Schultz (1944) both mention the resemblance of L. mystacinus and L. maracaiboensis , respectively, to L. guacharote , and suggest that because of the poor description, the identity of L. guacharote was uncertain and that a new species should be described. Schultz (1944) was further restricted from viewing the types of L. guacharote and L. mystacinus by the events of World War II.

Lasiancistrus guacharote occurs in one river in the río Meta - río Orinoco drainage of Colombia. These specimens are clearly L. guacharote as they have a patch of platelets ventrally near the insertion of the pectoral-fin spines, whiskerlike odontodes at the edge of the snout, and dark spots in the dorsal and caudal fins. Two other species are known from the río Orinoco, drainage: L. schomburgkii and L. tentaculatus . Lasiancistrus schomburgkii has white spots in the dorsal and caudal fins (vs. having dark spots in the fins), and L. tentaculatus has no abdominal plates and has tentacules along the snout instead of whiskerlike odontodes. The collection of these fishes (ANSP 128695) is from around Villavicencio, a town well connected with the aquarium export business. It is likely that the specimens of ANSP 128695 result from having been introduced from the aquarium trade. It is unknown if this population is extant.

Figures

Fig. 5. Dorsal, lateral, and ventral views of Lasiancistrus guacharote,AUM 22136, 80.1 mm SL.

Fig. 3. Range of species of Lasiancistrus. Open symbols are type localities except for in L. heteracanthus where the type locality is not specific. Triangles = L. schomburgkii, squares = L. caucanus, upside down triangles = L. guacharote, diamonds = L. heteracanthus, cross = L. saetiger, and circles = L. tentaculatus. The following are type localities for species in synonymy that have good locality information: 1. L. castelnaui (locality approximate), 2. L. guapore, 3. L. maracaiboensis, 4. L. mayoloi, 5. L. planiceps, 6. L. scolymus, 7. L. volcanensis.