Taxonomy of the catfish genus Pseudoplatystoma Bleeker (Siluriformes: Pimelodidae) with recognition of eight species. Uriel Angel Buitrago-Suárez Brooks M. Burr Zootaxa 2007 1512 1 38 4P84V Pimelodidae Pseudoplatystoma CoL Animalia Siluriformes 18 Chordata species orinocoense  (Figure 19, Table 4)  Geographic distribution: Orinoco River basin, Venezuela (Fig. 17).   FIGURE 19. Pseudoplatystoma orinocoense n. sp., holotype, INHS 35880, 489.7 mm SL. Scale 15 cm.  Material examined:   ANSP166466, (1), lago Merecure, 8º12'55"N, 63º17'25", Orinoco River, city of Bolivar, state of Bolivar, Venezuela, M. Rodriguez,  13 April 1988.   ANSP162391, (2), Orinoco River, at El Burro, 6º12N, 67º26'W, state of Amazonas, Venezuela, B. Chernoff et al., 16 November, 1985.   ANSP166790, (1), lagoon El Maldonado, Site El Almacen, 8º6'N, 63º45'50"W, Orinoco River, state of Bolivar, Venezuela, M. Rodriguez, 26 April, 1988.   AMNH77819, (1),  canoCaicara, at bridge on road from Mantecal, 7º22'N, 69º21W, Orinoco River, state of Apure, Venezuela, San Fernando fish station technicians,  24 January 1983.   INHS29298, (1), lagoon Curita, 8º9'30"N, 63º35'55", Orinoco River, state of Anzoategui, Venezuela, M. Rodriguez,  28 May 1987.   INHS61938, (1), San Bartolo River at Bartolena ranch, Guarico River, 7º59'20"N, 66º39'W, Orinoco River, state of Guarico, Venezuela, D. C. Taphorn et al.,  24 January 1986.   INHS34505, (1), San Bartolo River, Natural Park Aguaro, Guariquito River, 8º4'14"N, 66º40'50"W, Orinoco River, state of Guarico, Venezuela, D. C. Taphorn et al.,  8 January 1995.   INHS62069, (1 ds), Guariquito River, 7º54'40"N, 66º33'40"W, Orinoco River, state of Guarico, Venezuela, D. C. Taphorn et al.,  24 January 1986.   INHS29853, (1 ds), Apure River, Orinoco River, 2 km N of La Ve, 7º33'95"N, 69º15'48"W, state of Apure, Venezuela, L. M. Page et al.,  23 January 1993.   MCNG33258, (1), laguna El Potrero (Las Majadas), 7º36'40"N, 64º49'50"W, Orinoco River, state of Bolivar, Venezuela, M. Rodriguez,  15 January 1987.   MCNG1629, (1 ds), hato El Frio, Apure River, 7º45'S, 67º55'0"W, Orinoco River, state of Apure, Venezuela, D. Taphorn et al.,  10 February 1979.   MCNG36049, (1 ds), Sipao River, 6 km up stream from mouth, Orinoco River, district of Sucre, state of Bolivar, Venezuela, D. Rodriguez,  23 March 1997.   MCNG38851, (1 ds), Payara River front of mouth of Manglar River, Orinoco River, district of Penalver, state of Apure, Venezuela, D. Arana et al.,  12 December 1997.   UF80868, (1), laguna Chiriguare, Orinoco River, state of Portuguesa, Venezuela, D. Taphorn et al.,  3 April 1984.   UF78077, (1), 2 km N of San Fernando de Apure, between km markers 305 & 306, state of Guarico, Orinoco River, Venezuela, Taphorn et al.,  22 March 1981.   UF80651, (1), Guasimito River, tributary Guanare River, SE of Arismendi at Chalana site 8º20'55"N, 68º2'20"W, Orinoco River, state of Barinas, Venezuela, D. Taphorn et al.,  6 April 1984.   UMMZ211346, (2), tidal stream, 49 nautic miles, 8º38'N, 60º50'W, Orinoco River, Venezuela, J. Baskin and D. Stewart,  20 November 1979.   USNM258157, (1), Apure River, side channel along dike opposite to municipal slaughter house, 7º35' 0N, 67º29'0", state of Apure, Orinoco River, Venezuela, technicians of Apure fisheries,  25 January 1983.   USNM260211, (1),  canoW to highway from Calabozo San Fernando, about 35 km south of fundo Masaguaral ( canoFalcon), 8º14'0"N, 67º35' 0W, Orinoco River, state of Guarico, Venezuela, R. P. Vari et al.,  20 January 1983.   USNM258152, (1), same as 260211.   USNM258155, (2), small canoof Apure River, 7º53'0"N, 67º29'0"W, Orinoco River, state of Apure, Venezuela, technicians at Apure Fisheries,  21 January 1983.  Diagnosis: A species of Pseudoplatystomadistinguished by a combination of the following features: well defined straight vertical bars along side of body, longer than those of P. fasciatumand P. punctifer; bars connecting to, or extending to, the dorsal region and continuing onto other side of body; vertical bars of anterior region straight and extending below dorsolateral dusky area; usually no spots below lateral line, some individuals with two or three spots; 39-41 vertebrae.  Description: Maximum recorded length 489.7 mm TL. Body moderately stout, profile of head an acute triangle or pointed toward lips, almost flat anteriorly. Head margins somewhat parallel when viewed dorsally. Mouthrounded with mesethmoid, premaxilla, and lower jaw covered interiorly by thick skin. Viewed dorsally, body widest measurement at pectoral fins, and tapers gradually toward caudal peduncle. Dorsal margin from dorsal fin to adipose fin straight, dorsal margin posterior to adipose fin straight. Ventral margin from mouth to origin of anal fin straight. Posterior surface of head with thin skin leaving almost exposed grooves and roughness on the posterior region of cranium. Median fontanel short and covered by rough and thick skin. Anterior nostrils tubular and whitish, posterior ones with a whitish triangular flap. Eyes in dorsolateral position, ovoid and located at middle length of head. Maxillary barbels long, reaching origin of pelvic fins, their color blackish dorsally and yellowish ventrally. Chin barbels short in adults, not reaching beyond pectoral fin origin, longer in juveniles (<250 mm), extending beyond tip of pectoral spine. Opercle with pale flap on its margin.  FIGURE 20.  Pseudoplatystoma orinocoense, San Bartolo River (Orinoco River), Venezuela,  January 1986. Photoby Mark H. Sabaj. Head and rest of body dark dorsal and laterally. Dark pigmentation reaching lateral line. Some individuals pale others yellow ventrally. Vertical bars distributed along side of body. Number of bars greater than in congeners from Guyana ( P. fasciatum) (about 10 bars) and Amazon ( P. punctifer) (about 11 bars) and varying between 10 to 14 with an average of 12. Last bar on caudal fin often boomerang-like. Generally, dark bars accompanied by whitish bars. Few individuals with one or two dark loops on posterior region of head. Dorsal fin with few spots on spine and rays. Adipose fin with few spots decreasing in size toward the margin. Pectoral and pelvic fins dark dorsally, pale ventrally. A comparison with other species is presented in Table 9. Color and pattern of adults are shown in Fig. 20.  Etymology: The specific epithet orinocoense refers to the Orinoco River, Venezuela, the drainage in which this species is endemic.   TABLE 4. Descriptive measurements of the body size and shape (in mm), and number of vertebrae for P. orinocoense. Number of individuals measured, 27.     Variables Holotype mean+SD range  Standard length 489.7 300.3+93.5 208.2-524.2  Snout-posterior occipital process 170.3 119.1+32.8 87-207.9  Snout-posterior margin of the opercle 180 116.3+33.4 83.3-202.6  Dorsal fin spine length 61.2 37.1+11.8 22.2-64.7  Pectoral fin spine length 74.9 48.3+14.8 33.5-84.3  Maxillary barbel length 190.7 138.7+36.4 81.7-242.3  ...continued   TABLE4. (continued)    Variables Neotype mean+SD range  Anterior chin barbel length 174.1 121.8+32.8 90-212.6  Insertion maxillary barbel -eye 69.6 45.9+12.9 32.5-80.1  Insertion maxillary barbel -joint pectoral spine 136.5 88.4+25.6 62-154.3  Insertion maxillary barbel -joint dorsal spine 214.9 127.3+38.1 90.5-222.2  Eye -joint pectoral spine 75.1 49.6+15.6 33.3-86.7  Eye -joint dorsal spine 125.4 80.5+23.3 57.3-140.2  Joint pectoral spine -joint dorsal spine 89.1 54.2+15.6 38.5-94.6  Joint pectoral spine -joint first pelvic ray 121.3 70+23.5 44.5-122.2  Joint pectoral spine -joint last ray of dorsal fin 118.3 71.7+21.7 50.6-125.4  Joint dorsal spine -joint first pelvic ray 96.7 54.0+17.9 35.1-94.2  Dorsal fin base length 41.6 26.2+8.0 18-45.6  Joint first pelvic ray -joint last dorsal fin ray 71.3 39.7+12.5 27.4-69.3  Joint first pelvic ray -anal fin origin 124.3 71.8+24.1 47.5-125.9  Joint first pelvic ray -origin adipose fin 131.4 75.1+24.2 57.1-131  Last dorsal fin ray -anal fin origin 136.8 83.7+27.1 57.2-146.3  Last dorsal fin ray -adipose fin origin 109.9 69.2+22.5 47.8-120.8  Anal fin origin -adipose fin origin 60.6 35.4+11.1 24.1-61.9  Anal fin base length 48 32.2+11.6 22.2-68.9  Anal fin origin -adipose fin terminus 61.5 36.5+11.2 25.2-63.8  Adipose fin origin -anal fin terminus 70.7 42.7+12.9 28.5-74.6  Adipose fin length 42.5 26.6+8.0 17.4-46.5  Anal fin terminus -adipose fin terminus 36.8 21.7+6.6 14.6-37.9  Anal fin terminus -ventral caudal fin origin 20.9 11.1+3.7 7.5-20.9  Anal fin terminus -dorsal caudal fin origin 37 21.7+6.9 14.2-37.7  Adipose fin terminus -ventral caudal fin origin 49.9 27.9+9.0 18-48.7  Adipose fin terminus -dorsal caudal fin origin 30.1 17.1+5.7 9.7-30.1  Caudal peduncle depth 31.6 19.4+5.8 13.1-33.7  Number of vertebrae 40 40.07+0.47 39-41 923893584 1995-01-12 INHS D. Taphorn et al. Venezuela 7.6833334 near mouth of El Caujavito River, tributary of Orinoco River, southest of Cajarote -66.35 INHS 35880 state of Guarico Holotype 923893598 1979-11-19 AMNH Eastward et al. Venezuela 8.6066675 59 nautical miles from buoy, small cano emptying into cano Curiapo, Orinoco River -61.0 AMNH 96663 territorio federal delta Amacuro Paratype 923893580 1979-11-19 AMNH Eastward et al. Venezuela 8.6 very small primary cano on isla Guacujana south shore, Orinoco basin -60.933334 AMNH 96662 territorio federal delta Amacuro Paratype 923893573 1988-04-18 ANSP M. Rodriguez Venezuela 8.1 El Almacen L. Maldonado, Orinoco River -63.76389 ANSP 166790 state of Bolivar Paratype 923893591 1978-02-21 USNM J. Lundberg Venezuela 8.483334 small cano on W side of cano Paloma, Orinoco River -61.416667 USNM 233830 territorio federal delta Amacuro Paratypes 923893583 1988-04-13 ANSP M. Rodriguez Venezuela 8.215278 lago Merecure, Orinoco River, city of Bolivar -63.290278 ANSP 166466 state of Bolivar 923893581 1985-11-16 ANSP B. Chernoff et al. Venezuela 6.2 Orinoco River, at El Burro -67.433334 ANSP 162391 state of Amazonas 923893594 1988-04-26 ANSP M. Rodriguez Venezuela 8.1 lagoon El Maldonado, Site El Almacen, Orinoco River -63.76389 ANSP 166790 state of Bolivar 923893593 1983-01-24 AMNH San Fernando fish station technicians Venezuela 7.366667 cano Caicara, at bridge on road from Mantecal, Orinoco River -69.35 AMNH 77819 state of Apure 923893586 1987-05-28 INHS M. Rodriguez Venezuela 8.158333 lagoon Curita, Orinoco River -63.598611 INHS 29298 state of Anzoategui 923893590 1986-01-24 INHS D. C. Taphorn et al. Venezuela 7.988889 San Bartolo River at Bartolena ranch, Guarico River, Orinoco River drainage -66.65 INHS 61938 state of Guarico 923893596 1995-01-08 INHS D. C. Taphorn et al. Venezuela 8.070556 San Bartolo River, Natural Park Aguaro, Guariquito River, Orinoco River drainage -66.68055 INHS 34505 state of Guarico 923893578 1986-01-24 INHS D. C. Taphorn et al. Venezuela 7.9111114 Guariquito River, Orinoco River drainage -66.56111 INHS 62069 state of Guarico 923893599 1993-01-23 INHS L. M. Page et al. Venezuela 7.5763893 Apure River, Orinoco River, 2 km N of La Ve -69.263336 INHS 29853 state of Apure 923893606 1987-01-15 MCNG M. Rodriguez Venezuela 7.611111 laguna El Potrero (Las Majadas), Orinoco River -64.83055 MCNG 33258 state of Bolivar 923893600 1979-02-10 MCNG D. Taphorn et al. Venezuela -7.75 hato El Frio, Apure River, Orinoco River drainage -67.916664 MCNG 1629 state of Apure 923893604 1997-03-23 MCNG D. Rodriguez Venezuela Sipao River, 6 km up stream from mouth, Orinoco River MCNG 36049 district of Sucre, state of Bolivar 923893601 1997-12-12 MCNG D. Arana et al. Venezuela Payara River front of mouth of Manglar River, Orinoco River MCNG 38851 district of Penalver, state of Apure 923893609 1984-04-03 UF D. Taphorn et al. Venezuela laguna Chiriguare, Orinoco River UF 80868 state of Portuguesa 923893605 1981-03-22 UF Taphorn et al. Venezuela 2 km N of San Fernando de Apure, between km markers 305 & 306, Orinoco River drainage UF 78077 state of Guarico 923893595 1984-04-06 UF D. Taphorn et al. Venezuela 8.348611 Guasimito River, tributary Guanare River, SE of Arismendi at Chalana site, Orinoco River drainage -68.03889 UF 80651 state of Barinas 923893597 1979-11-20 UMMZ J. Baskin and D. Stewart Venezuela 8.633333 tidal stream, 49 nautic miles, Orinoco River -60.833332 UMMZ 211346 923893602 1983-01-25 USNM technicians of Apure fisheries Venezuela 7.583333 Apure River, side channel along dike opposite to municipal slaughter house, Orinoco River drainage -67.483333 USNM 258157 state of Apure 923893607 1983-01-20 USNM R. P. Vari et al. Venezuela 8.233334 cano W to highway from Calabozo San Fernando, about 35 km south of fundo Masaguaral (cano Falcon), Orinoco River -67.583333 USNM 260211 state of Guarico 923893610 1983-01-20 USNM R. P. Vari et al. Venezuela 8.233334 cano W to highway from Calabozo San Fernando, about 35 km south of fundo Masaguaral (cano Falcon), Orinoco River -67.583333 USNM 258152 State Of Guarico 923893603 1983-01-21 USNM technicians at Apure Fisheries Venezuela 7.883333 small cano of Apure River, Orinoco River drainage -67.48333 USNM 258155 state of Apure 923893608 1986-01 Photo Mark H. Sabaj Venezuela San Bartolo River (Orinoco River)