Hypostomus pyrineusi Miranda-Ribeiro 1920

Jonathan W. Armbruster, 2003, The species of the Hypostomus cochliodon group (Siluriformes: Loricariidae)., Zootaxa 249, pp. 1-60 : 46-49

Hypostomus pyrineusi Miranda-Ribeiro 1920

(Fig. 20)

Hypostomus pyrineusi Miranda-Ribeiro 1920 : 9, pls. 3-4.

Material examined: BOLIVIA. Beni:, Río Curiraba, Río Madeira dr. Campamento Trapiche, USNM 305281, 1, (119.8) . Río Itenez, Río Beni - Río Madeira dr. 5 km S Costa Marques, Brasil, 1 km above mouth of Río Baures, AMNH 39941, 1, (210.1) . Río Itenez, Río Beni dr. 9 km SE of Costa Marques, Brasil, UMMZ 204399, 5, (139.9-226.7) . Río Itenez, Río Beni - Río Madeira dr. opposite Costa Marques, Brasil, AMNH 39758, 2, (92.0-213.4) . Río Itenez, Río Beni - Río Madeira dr. playa pond, 9 km SE Costa Marques, Brasil, AMNH 40108 (none measured) . Río Maniqui, Río Marmore - Río Madeira dr. San Borja, INHS 36995, 2, (162.7-176.0) . BRAZIL. Acre: Rio Macauhan, Rio Yaco - Rio Purus dr. vicinity of Rio Macauhan, USNM 94653, 1, (122.5) . Rio Macaua, Rio Iaco dr. near Sena Madueira, 09°20’S, 68°45’W, AMNH 12599, 1, (113.5) . Amazonas: Rio Jamari, MNRJ 863, 1, (204.0) , Holotype: ECUADOR. Napo: Río Catapino, Río Corrientes - Río Napo dr. MCNG 9724, 1, (174.8) . Río Pucuno, Rio Suno - Rio Napo dr. 00°47’S, 77°16’W, USNM 177222, 1, (71.3) . Río Lushian, Río Misahuali dr. at bridge E of Rucullacta, 00°54’42”S, 77°48’48”W, CAS 106013 . Shansho Caño, USNM 124875, 1, (100.5) . PERU. Amazonas: Río Marañon dr. 1 km upstream from Caterpiza, LACM 42005-13, 2, (84.1-89.5) and LACM 42003-8, 2, (150.6-174.3) . Río Marañon dr. 100 m downstream from Caterpiza, LACM 41996-9, 1, (137.1) and LACM 41972-3, 1, (140.9) . Río Marañon dr. 300 m upstream from Caterpiza, LACM 41813-1, 1, (207.7) . Río Marañon dr. 500 m upstream from Caterpiza, LACM 41992-7, 4, 1 cs, (162.4-190.1) and LACM 42010-8, 1, (108.0) . Río Marañon dr. 800 m upstream from Caterpiza, LACM 41834-1, 1, (131.2) . Río Marañon dr. Caterpiza, LACM 41873-7, 1, (180.7) , LACM 41882-4, 1, (180.9) , LACM 41884-1, 1, (198.9) , LACM 41887-5, 1, (160.3) , LACM 42009-10, 1, (133.9-164.9) , LACM 41898-2, 1, (140.0) , LACM 41893-9, 2, 1 cs, (152.8-163.2) , LACM 42115-8, 1, (104.7) , LACM 41895-6, 1, (152.8-163.2) , and LACM 42116-4, 1, (93.0) . Quebrada Kayamasa, Río Marañon dr. 40 km upstream from Caterpiza, FMNH 97016, 1, (140.9) , LACM 41872-4, 2, (150.9-187.7) , LACM 41846-4, 1, (199.7) , LACM 41852-1, 1, (173.6) , and LACM 41853-4, 2, (136.7-156.4) . Quebrada Pastazilla, Río Santiago - Río Marañon dr. LACM 39947-8, 2, (208.5-215.1) . Quebrada Yutupiza, Río Marañon dr. LACM 36337-10, 1, (159.4) . Río Cenepa, Río Marañon dr. near San Antonio, LACM 39638-3, 3, 1 cs, (94.2-202.8) . Río Huampani, Río Marañon dr. Maja Quebrada, LACM 36359-2, 1, (228.0) . Río Marañon, Río Amazonas dr. at and across from Sta. Maria de Nieva and confluence of Río Nieva, FMNH 97017, 2, (110.6-131.9) . Río Santiago, Río Marañon dr. at La Poza, LACM 41724-17, 1, (131.5) , LACM 41723-10, 1, (130.5) , LACM 41729-39, 1, (147.7) , LACM 41730-11, 1, (128.8) , LACM 39883-11, 3, 1 cs, (137.9-170.8) . Huanaco:, Río Huallaga, Río Ucayali dr. at Tingo Maria, CAS 56754, 2, 1 cs, (79.6-86.1) and CAS 95117, 2, 1 cs, (69.7-160.5) . Río Rondos, Río Monzon dr. vicinity of Tingo Maria, just above new bridge site, ANSP 38873 (none measured) . Loreto: Río Amazonas, Atlantic Ocean dr. INHS 39358 (none measured) . Río Amazonas, Atlantic Ocean dr. 21.1 mi NE Iquitos bearing 22°, 03°30’30”S, 73°03’28”W, INHS 39122 (65.2) . Río Amazonas, Atlantic Ocean dr. at Pueblo Gallito, INHS 36939, 1, (80.3) . Río Itaya, Río Amazonas dr. approx. 10 km S Santa Clara, INHS 36877, 1, (94.8) . Río Nanay, Río Amazonas dr. well above Morona cocha, ANSP 38874 (none measured) . Río Napo, Río Amazonas dr. at Mazan, INHS 36565 (none measured) . Madre de Dios:, Caño Pachija, Río Madre de Dios dr. Manu National Park, Pakitza, from mouth to 7 km upstream, USNM 319601, (81.2) . Caño Picaflor, Río Madre de Dios dr. Pakitza, Caña Brava Trail #19, USNM 319353, 1, (114.1) . Tributary, Río Tambopata - Río Madre de Dios dr. stream enters Río Tambopata from S bank approximately 500 m downstream of Explorer’s Inn boat landing, 12°49’35”S, 69°17’30”W, USNM 264049, 1, (178.5) . Tributary to Río Madre de Dios, on S side about 10 km downstream of junction of Río Tambopata and Río Madre de Dios, 12°30’S, 69°10’W, USNM 263911, 1, (130.1) . Tributary, Río Tambopata - Río Madre de Dios dr. second stream entering Río Tambopata on SW shore upstream of mouth of Río La Torre, 12°49’40”S, 69°18’W, USNM 264050, 2, (143.0-202.6) .

Diagnosis: Hypostomus pyrineusi is distinguished from most members of the H. cochliodon group except some H. cochliodon , H. levis , H. ericius , H. oculeus , and H. taphorni by having 0-10 (usually 0; Fig. 2B) odontodes on the opercle (vs. 11 or more). Hypostomus pyrineusi further differs from H. hemicochliodon and H. sculpodon by lacking a ridge on the pterotic-supracleithrum (Fig. 5B), by the presence of large, spoonshaped teeth (vs. teeth intermediate; Fig. 1C vs. B), and a lack of a buccal papilla; from H. ericius , H. hemicochliodon , H. oculeus , and H. sculpodon by lacking strong, sharp keels on the lateral plates; from H. levis by having an adipose fin; from H. cochliodon by having the spots more numerous and close-set on the body (vs. spots absent or widely spaced); and from H. taphorni by having pigmentation on the lobes of the caudal fin equally distributed (vs. lower lobe darker than upper).

Description: See Hypostomus cochliodon group description for more details. Morphometric data given in Table 5. Body typically almost entirely dark brown with medium to large spots present. Spots on head fairly large when compared to those of H. hondae , H. pagei , and H. taphorni . Spots increasing in size and fading posteriorly, absent on caudal peduncle. Spots on abdomen typically large, some specimens with medium-sized spots, spots never as small as in H. taphorni ; (Fig. 22). Spots occasionally absent and entire fish dark brown (almost black). Caudal fin may be entirely spotted, but caudal-fin membranes and rays typically black or black distally and light proximally; caudal-fin spines typically spotted although some specimens with entirely black caudal-fin spines; caudal fin not bicolored. Abdomen colored as sides, sometimes slightly lighter. Color in juveniles as in adults, but spots comparatively larger and abdomen generally white and unspotted.

Dorsal fin short, rarely reaching preadipose plate when depressed. Depressed pectoralfin spine ventral to pelvic fin reaches 2-3 plates beyond pelvic-fin rays. Tip of pectoral-fin spine of nuptial males with stout, recurved, hypertrophied odontodes.

Keels weak to moderately developed. Orbits forming moderate ridge slightly raised above medial surface of head; ridges of dorsal and lateral aspect of head fairly well-developed. Longitudinal ridge on pterotic-supracleithrum beginning at posterodorsal corner of eye formed from raised bone and slightly larger odontodes absent. Opercle usually supporting no odontodes, but occasionally one to three odontodes are present. Nuptial body odontodes present (Fig. 2B). Plates in skin anterior to dorsal-fin spine absent or few (Fig. 6A; Table 7).

Each jaw with 5-14 teeth (mode = 8), teeth large and spoon-shaped. Average angle between dentaries 55° (SD = 7°; range: 43°-69°, N=30). Lateral line plates 26-31; dorsal plates 8-9; interdorsal plates 4-7; adipose caudal plates 9-16.

Range: Found in the Río Madeira drainage of Bolivia and Brazil, the Ríos Napo, Ucayali, Marañon and upper Río Amazonas drainage of Peru, and the Río Napo drainage of Ecuador, (Fig. 8). Hypostomus pyrineusi is sympatric with H. ericius , H. hemicochliodon , and H. oculeus and is potentially sympatric with H. levis .