Steindachner, 1879a : 152
Steindachner, 1879b : 170
Pearson, 1937 : 90
A revision of the cis-andean species of the genus Brycon Müller & Troschel (Characiformes: Characidae)
Lima, Flávio C. T.
Zootaxa
2017
4222
1
1
189
NH8L
Steindachner, 1879
Steindachner
1879
[151,621,1342,1368]
Actinopterygii
Bryconidae
Brycon
Animalia
Characiformes
16
17
Chordata
species
stolzmanni
Brycon stolzmanni Steindachner, 1879a: 152(Type locality, “Chota”; brief description); Steindachner, 1879b: 170, pl. 2, figs.6, 6a (full description); Pearson, 1937: 90(Peru: Balsas; Paipay, Rio Crisnejas; Tingo de Pauca, Rio Marañon; Pusoc, above Balsas).
Diagnosis. Brycon stolzmannican be distinguished from all remaining cis-andean Bryconspecies, except B. coxeyi, by possessing a distinct patch of dark pigmentation on the opercle (vs. patch of dark pigmentation on the opercle absent in the remaining cis-andean Bryconspecies) and infraorbital series not closed, with the orbital margin partially delimited by the frontal bone (vs. infraorbital series closed, frontal excluded from the orbital series by the contact between the supraorbital and the sixth infraorbital bone). Brycon stolzmannican be distinguished from B. coxeyiby possessing the dark patch of pigmentation on the opercle diffuse and covering the upper half of the bone (vs. dark patch of pigmentation on opercle very conspicuous and typically lying at its center).
Description.Morphometric data are presented in Table 1. Relatively small-sized species, largest examined specimen 214.0 mm SL. Body moderately high. Largest body height at dorsal-fin level. Dorsal body profile slightly convex from upper lip margin to vertical through anterior naris, slightly concave to slightly convex from latter point to basis of supraoccipital process, and moderately convex from latter point to dorsal-fin origin, straight along dorsal-fin basis, straight to slightly convex from dorsal-fin terminus to adipose-fin origin. Dorsal profile of caudal peduncle slightly concave. Ventral profile slightly convex from lower lip to pelvic-fin insertion, slightly convex to straight from this point to anal-fin origin and approximately straight along anal-fin base. Ventral profile of caudal peduncle slightly concave. TABLE 1.Morphometric data of Brycon stolzmanni(A: lectotype, NMW 62731). A n Range Mean Standard length (SL) 124.5 36 66.6–185.5 - Percentages of standard length Depth at dorsal-fin origin 33.0 36 29.9–34.0 31.8 Snout to dorsal-fin origin 52.0 36 48.5–53.4 51.0 Dorsal-fin base length 12.4 36 10.6–14.9 12.6 Posterior terminus of dorsal fin to adipose fin 21.8 36 21.1–26.6 23.6 Posterior terminus of dorsal fin to hypural joint 39.0 36 35.5–42.9 39.0 Snout to pelvic-fin insertion 52.0 34 47.9–53.3 49.9 Snout to anal-fin origin 69.4 36 63.3–69.4 66.0 Anal-fin base length 22.5 35 19.4–23.9 22.0 Caudal peduncle length 13.5 36 13.5–18.8 17.1 Dorsal-fin height 22.2 36 16.2–25.1 20.9 Pectoral-fin length 20.3 36 18.4–22.7 20.1 Pelvic-fin length 14.9 36 13.6–17.6 15.2 Caudal peduncle depth 11.5 36 10.2–12.1 11.4 Head length 29.4 36 26.2–31.1 27.8 Percentages of head length Head height 79.8 36 76.7–90.8 82.8 Snout length 26.0 36 23.0–30.1 26.8 Upper jaw length 42.9 35 40.4–45.3 43.2 Horizontal eye diameter 21.3 36 21.3–28.9 24.0 Post-orbital length 52.5 36 49.0–56.3 52.6 Least interorbital width 32.0 35 27.0–37.5 32.1 Head profile rounded to slightly acute anteriorly, mouth terminal. Maxillary extending posteriorly to vertical slightly anterior to middle of pupil. Adipose eyelid well developed. Premaxillary teeth in three rows; teeth of third row largest. Five (7), 6 (16), 7 (10) or 8 (1) tricuspidate teeth in outer series. Two (4), 3 (25), or 4 (7) tri- to pentacuspidate teeth in second, inner premaxillary row, plus 3 (30) or 4 (6) tricuspidate teeth between the first and third rows. Two teeth in third premaxillary row, medial teeth largest, symphyseal teeth smaller, both pentacuspidate. Maxillary with distal portion expanded and rounded in profile. Eleven to 18 maxillary teeth, slightly smaller than teeth of first premaxillary row, anterior teeth tricuspidate, posterior teeth unicuspidate. Dentary with 6 (1), 7 (3), 8 (1), 9 (1), or 10 (1) teeth in main series. Anterior four dentary teeth assymetrical, considerably larger and bulkier than remaining teeth, tetra- to pentacuspidate, each with central cusp distinctly larger than remaining cusps. Remaining dentary teeth progressivelly smaller, tri- to unicuspidate. Inner (lingual) series consisting of a single unicuspid symphyseal tooth, considerably smaller than teeth of main series anterior to it, plus row of 5 small, unicuspidate teeth, originating at level of 7th tooth of main series. Scales cycloid. Lateral line complete, from supracleithrum to caudal-fin base. Forty-three (1), 44 (3), 45 (6), 46 (10), 47 (12), 48 (3), or 49 (1) scales in lateral line series; laterosensory tube simple, tube often deflected downwards. Horizontal scale rows between dorsal-fin origin and lateral line 8 (17), 9 (16), or 10 (3). Horizontal scale rows between lateral line and pelvic-fin 4 (4), 5 (15), or 6(17). Circumpeduncular scales 16 (18), 17 (9), or 18 (9). Dorsal-fin rays ii, 9. Dorsal fin origin slightly anterior to middle of SL. First dorsal-fin pterygiophore inserting behind neural spine of 12th vertebrae. Dorsal fin displaying numerous (c. 10–35 per fin-ray main branch) small hooks on last unbranched and posterior main branch of all branched rays in one specimen (ROM 55348, 128.8 mm SL). Anal-fin rays iii (not including first, small unbranched ray only visible in the cs specimen), 19 (1), 20 (6), 21 (16), 22 (12), or 23 (1). First anal-fin pterygiophore inserting behind haemal spine of 22th vertebrae. Last unbranched and anterior 2–3 branched anal-fin rays longer, remaining rays progressively shorter towards anal-fin end. Anal fin displaying numerous (c. 15–35 per fin-ray main branch) small hooks associated with dense, gelatinous tissue on last unbranched and posterior main branch of all branched rays except posteriomost ray in one specimen (ROM 55348, 128.8 mm SL). Small hooks also present in the anterior main anal-fin branch in the two anteriormost anal-fin rays. Sheath of scales composed of a single series composed by 16–20 rectangular scales, covering basis of anal-fin rays. Pectoral-fin rays i, 11 (1), 12 (15), 13 (18), or 14 (2). Pelvic-fin rays i,7. Branched pelvic-fin rays with minutes hooks (c.10 per branch) on distal portion of posterior ray branches in one specimen (ROM 55348, 128.8 mm SL). Main caudal-fin rays 10/9. Caudal fin forked, lobes rounded. Four branchiostegal rays. First gill arch with 11(1) lower gill rakers, 11(1) upper gill rakers and 1 at angle. Vertebrae 43 (1). Supraneurals 9 (1). FIGURE 7. Brycon stolzmanni, lectotype, NMW 62731:1, 124.5 mm SL: Peru, Cajamarca, Chota. FIGURE 8. Brycon stolzmanni, ROM 52237, 160.5 mm SL: Peru, Cajamarca, Río Huacabamba. Coloration in alcohol.Top of head, snout, supraorbital, sixth and dorsal portion of fifth infraorbitals, and dorsal portion of body dark grey to dark brown. Dentary, maxillary, lower infraorbitals, gular area and ventral portion of body light to cream-colored. Opercle dark-colored, its lower half dark-grey, suffused with silvery pigmentation, while upper half dark brown. Humeral blotch present, split in two halves, lower half more conspicuous, roughly triangular-shaped, with the apex directed downwards, crossed at its lower portion by the lateral line, extending horizontally from the third to the fifth to sixth lateral line scales. Upper half of humeral blotch less conspicuous, separated from lower half of humeral blotch by a narrow clear-colored area, two and a half scales rows high. Caudal peduncle blotch present, relatively conspicuous, rounded, extending throughout 3–4 last lateral line scales into basis of 3–4 innermost caudal-fin rays. Caudal, anal and dorsal-fins with numerous small dark chromatophores scattered over interradial membranes. Pectoral and pelvic-fins with relatively few dark chromatophores on interradial membranes. Adipose fin dark brown, with a conspicuous clear-colored rounded spot at its basis. FIGURE 9. Brycon stolzmannni, ZUEC 6850, 101.4 mm SL, Peru, Amazonas, Río Tingo. Sexual dimorphism.The single examined specimen bearing hooks on dorsal, pelvic- and anal-fins (ROM 55348, 128.8 mm SL) was found to be a male upon dissection. The largest specimen examined, NMW 62728 (214.0 mm SL), is a female with well-developed ovaries, which does not possess fin hooks.
Distribution. Brycon stolzmanniis known from the upper Río Marañonand its tributaries at the Departamentos Cajamarca, Lambayeque, and Amazonas, Peru( Fig. 10). Fowler (1943: 4)and Howes (1982: 44)incorrectly assigned the species for the Pacific slope of the Andean cordillera. FIGURE 10.Map of northwestern South America showing known localities of Brycon stolzmanni(red dots), and B. coxeyi(black dots). Ecological notes. Brycon stolzmanniis recorded from Andean rivers in altitudes ranging at least from 870– 1087 meters high. The typelocality, Chota, is situated in the headwaters of the RíoChamaya, a tributary of the upper Río Marañon, at a considerably higher altitude (2400 meters high). However, its is uncertain whether the typespecimens were collected at Chota itself or in a neighboring river valley, and consequently we did not included this record in the altitudinal range cited above. The Río Marañonand its tributaries at the area of occurrence of Brycon stolzmanniare swift-flowing, white-water rivers possessing coarse gravel and rocky substrates running over braided channels, deeply entrenched in valleys crossing the mountains.
Remarks. Steindachner (1879a: 152)succinctly described Brycon stolzmanni, a complete description and a illustration of the species appearing a little later (1879b: 22). The species was described based on two specimens collected at Chota, upper Río Marañon basin, Departamento Cajamarca, Peru. The two syntypes (NMW 62731) were examined, the largest of which is herein designated as the lectotype of the species. There have been almost no subsequent published information on the species, and in fact, Pearson (1937)report of the species for several localities in the upper Río Marañon basin in Peru was the sole paper to add original information on the species up to now.
Material examined. Typematerial. NMW62731:1 ( 1, 124.5 mmSL): Chota( Peru, Depto. Cajamarca, Rio Marañonbasin, c. 6°33’S, 78°39’W); Stolzmann, no date. Lectotypeby present designation of Brycon stolzmanniSteindachner. NMW62731:2 (1, 88.4 mmSL); same data as lectotype. Paralectotype. Non types. Allfrom Peru, Rio Maranõndrainage. Departamento Cajamarca: ROM52237 (5 of 51, 146.8– 160.5 mmSL), approx. 74 kmW of road going N to Jaen, between Pucara and Guabal, Chamaya River, Huacabamba River(tributary Amazon/ Marañondrainage), c. 5°57’S, 79°13’W; E. Holm& J. Patalas, 8 Jul 1986. CAS77371 (69, 27.3–72.5 mmSL), RioCrisnejas, at mouth of RioPaipay at Paipay, c. 7°21’S, 77°53’W; N.E. Pearson, Aug 1923. NMW 62728 (1, 214.0 mm SL); NMW62933 (1, 88.5 mmSL), Celendín, Hacienda Callacate, 6°46'S, 78°16'W; W. Taczanowski, 1880. MUSM41333(9, 20.5–37.2 mmSL): Celendín, RíoLlanguat ( Río Marañonbasin), 6°47’19’’S, 78°12’55’’W; H. Ortega et al., 25 Sept 2011. Departamento Amazonas: ROM55347 ( 1, 163.7 mmSL), Luya, Huanabamba, about 16 kmby road upstream from Balsas, Amazon/ Marañondrainage, 6°52'S, 78°00'W; E. Holm et al., 27 June 1986. ROM55348 (2, 128.8– 132.7 mmSL), confluence of “El Río” (creek running through Balsas) at Puerto Balsas, 6°50'S, 78°01'W; E. Holm et al., 28 Jun 1986. UMMZ 185306 (28, 49.6–130.7 mmSL); UMMZ216716(5, 107.3– 185.5 mmSL): Rio Maranõnat Balsas, 6°50’S, 78°1’W; N.E. Pearson, July 1923. CAS77370 (ex IU 17599) (6 of 94, 20.9–33.2 mmSL), Río Marañon, Pusoc( Guayabamba), above Balsas, c. 6°57’S, 78°00’W; N.E. Pearson, Aug 1923. CAS77372 (32, 21.5–42.9 mmSL), Río Marañonat Tingo de Pauca, mouth of RíoCrisnejas, c. 7°20’S, 77°49’W; N.E. Pearson, Sept 1923. MUSM10611(5, 65.8–94.0 mm SL): RíoUctubamba, Lluhuana; F. Chang, 23 Nov 1996. MUSM40548(1, 85.0 mm SL): Bongará, Shipasbamba, RíoUctubamba (trib. Río Marañon), 5°54’45’’S, 78°3’50’’W; M. Jaico et al., 12 Jul 2011. MUSM 41145 (44, 45.9–105.2 mmSL); ZUEC6850(4, 58.9–101.4 mmSL): Amazonas, Bongara, Jazan, RíoTingo (trib. RíoUctubamba), 5°55’2’’S, 78°4’35’’W; M. Hidalgo& I. Corahua, 29 June 2011. MUSM41146(8, 62.1–99.0 mm SL): Amazonas, Bongara, Jazan, RíoUtcubamba (island), 5°55’1’’S, 78°4’32’’W; M. Hidalgo& I. Corahua, 29 June 2011. Departamento Lambayeque: MUSM30230(1, 35.5 mmSL): Ferreñafe, Kañaris, CCA Huancabamba, RíoCañariaco, mouth at RíoHuancabamba, 5°56’15’’S, 79°15’47’’W; B. Renjifo & V. Meza, 24 May 2007. Without data:MUSM uncat. ( 1, 133.7 mmSL, cs).
1425222693
NMW
Peru
-6.55
Rio Maranon
1304
-78.65
Chota
20
21
1
Cajamarca
holotype
1425222678
NMW
Peru
-6.55
Rio Maranon
1304
-78.65
Chota
20
21
1
Cajamarca
lectotype
1425222671
1986-07-08
ROM
E. Holm & J. Patalas
Peru
Non
-5.95
Rio Maranon
1305
-79.21667
All
20
21
1
Cajamarca
holotype
1425222676
[151,1372,871,896]
CAS
Peru
-7.35
Paipay
1303
-77.88333
20
21
1
Rio
holotype
1425222688
NMW
Peru
-6.7666664
Hacienda Callacate
1304
-78.26667
Celendin
20
21
1
Rio
holotype
1425222695
2011-09-25
MUSM
W. Taczanowski & H. Ortega
Peru
-6.788611
Celendin
21
-78.21527
20
21
MUSM 41333
1
Rio
holotype
1425222687
1986-06-27
ROM
E. Holm
Peru
Luya
-6.866667
Balsas
1303
-78.0
Huanabamba
20
21
1
Amazonas
holotype
1425222684
ROM
Peru
-6.8333335
Puerto Balsas
1303
-78.01667
Balsas
20
21
1
Rio
holotype
1425222668
1923-07
UMMZ
N. E. Pearson
Peru
-6.8333335
Balsas
1303
-78.01667
20
21
UMMZ 216716
1
Rio Maranon
holotype
1425222692
CAS
Peru
Pusoc
-6.95
Balsas
1303
-78.0
Guayabamba
20
21
1
Rio Maranon
holotype
1425222701
1923-08
CAS
N. E. Pearson & Tingo de Pauca
Peru
-7.3333335
Tingo de Pauca
1303
-77.816666
20
21
1
Rio Maranon
holotype
1425222702
1996-11-23
MUSM
Lluhuana & F. Chang
Peru
Rio
20
21
MUSM 10611
1
Rio
holotype
1425222699
MUSM
Peru
-5.9125
Shipasbamba
21
-78.06389
Bongara
20
21
MUSM 40548
1
Rio
holotype
1425222700
[630,1381,1340,1365]
ZUEC
Peru
Jazan
Bongara
20
21
ZUEC 6850
1
Amazonas
holotype
1425222694
Peru
-5.917222
Rio
21
-78.076385
20
21
1
Rio
holotype
1425222707
[764,1223,1375,1400]
2011-06-29
I. Corahua
Peru
Hidalgo
20
21
1
Hidalgo
holotype
1425222719
MUSM
Peru
Jazan
Bongara
20
21
MUSM 41146
1
Amazonas
holotype
1425222712
[698,1241,1412,1437]
Peru
-5.9169445
Rio
21
-78.075554
20
21
1
Rio
holotype
1425222713
2011-06-29
I. Corahua
Peru
Hidalgo
20
21
1
Hidalgo
holotype
1425222704
[425,1367,1447,1472]
MUSM
Peru
Kanaris
Ferrenafe
20
21
MUSM 30230
1
Lambayeque
holotype
1425222708
CCA
Peru
-5.9375
Huancabamba
21
-79.263054
20
21
1
Rio
holotype