Bryconops munduruku, Silva-Oliveira, Cárlison, Canto, André Luiz C. & Ribeiro, Frank Raynner V., 2015

Silva-Oliveira, Cárlison, Canto, André Luiz C. & Ribeiro, Frank Raynner V., 2015, Bryconops munduruku (Characiformes: Characidae), a new species of fish from the lower Tapajós River basin, Brazil, Zootaxa 3994 (1), pp. 133-141: 134-138

publication ID

http://dx.doi.org/10.11646/zootaxa.3994.1.7

publication LSID

lsid:zoobank.org:pub:D9D78466-2E20-4BAA-8520-E0F2FBBDDB1D

DOI

http://doi.org/10.5281/zenodo.5671719

persistent identifier

http://treatment.plazi.org/id/4268F84B-2257-4F02-FF41-E9F8DED21B82

treatment provided by

Plazi

scientific name

Bryconops munduruku
status

new species

Bryconops munduruku   , new species

( Figures 1–3 View FIGURE 1 View FIGURE 2 View FIGURE 3 ; Table 1 View TABLE 1 )

Holotype. INPA 46510, male, 76.6 mm SL, Brazil, Pará State, Aveiro, igarapé Açu, tributary of the right margin of the Tapajós River, about 10 km of the city of Aveiro, 0336’ 0.99 ’’S 5514 ’ 59.14 ’’W, 23 May 2013, C. Silva-Oliveira & S. R. Oliveira.

Paratypes. All collected with holotype, Brazil, Pará State, Tapajós River basin: MCP 48315 View Materials (5, 34.0– 79.6 mm SL); INPA 46511 (11, 33.5–91.7 mm SL; 2 c&s, 31.8–74.1 mm SL); UFOPA-I-00655 (7, 33.4–96.4 mm SL; 5 c&s, 47.6–63.3 mm SL).

Diagnosis. Bryconops munduruku   differs from its congeners, except B. inpai   and B. piracolina   , by possessing a black adipose fin (vs. adipose fin hyaline in alcohol). It differs from B. inpai   and B. piracolina   by possessing a hyaline band on the black adipose-fin base (vs. entirely black adipose fin in B. piracolina   and B. inpai   ). Bryconops munduruku   differs further from B. piracolina   by having a hyaline dorsal fin (vs. presence of a large black blotch on the dorsal-fin base). Bryconops munduruku   differs from other species of the subgenus Creatochanes   , except B. inpai   , by possessing two humeral blotches (vs. lack of humeral blotch or humeral region with a single humeral blotch in B. humeralis   and B. vibex   ). It differs further from B. inpai   due to the uniform color pattern on the posterior portion of the side of the body (vs. presence of a dark stripe extending posteriorly from the half of the anal-fin base onto the base of the middle caudal-fin rays).

Description. Morphometric data presented in Table 1 View TABLE 1 . Body shape compressed, greatest body depth located just anterior to dorsal-fin origin. Dorsal profile of body slightly convex from snout tip to dorsal-fin origin; straight to slightly concave from dorsal insertion to adipose-fin origin, gently sloping to beginning of caudal peduncle.

Caudal peduncle concave along dorsal and ventral margins. Ventral profile of head and body convex from lower lip to pelvic-fin origin, and straight from this point to anal-fin origin. Ventral profile straight and posterodorsally inclined along anal-fin base.

Mouth terminal. Posterior extension of maxilla reaching junction between second and third infraorbital bones ( Fig. 2 View FIGURE 2 ); third infraorbital moderately developed, reaching preopercle ventrally. Supraorbital bone present. Premaxillary teeth in two rows, with midcentral cusp more developed than remaining cusps; outer teeth row with 5 * (9) or 6 (3) tricuspid teeth; inner tooth row with 5 * (10) pentacuspid teeth. Maxillary with 1 (2), 2 * (15), or 3 (1) tri- or tetracuspid teeth on contralateral parts ( Fig. 3 View FIGURE 3 ). Dentary with 5 (2) or 6 * (6) penta- or hexacuspid teeth, followed by 6 smaller conical teeth.

Dorsal-fin rays ii, 8 (3) or ii, 9 * (28); first unbranched ray about one-half length of second unbranched ray. Dorsal-fin origin slightly ahead of mid-body, positioned vertically through anterior third of pelvic-fin base. Posterior margin of dorsal fin straight to slightly concave. Adipose-fin origin approximately at vertical through base of 18 th to 19 th anal fin branched rays. Principal caudal-fin rays i,8,8,i (7) or i,8,9,i* (23). Lobes of caudal fin unequal, lower lobe slightly longer than upper lobe. Dorsal procurrent caudal-fin rays 14 (5), ventral procurrent caudal-fin rays 13 (4) or 14 (1). Pectoral-fin rays i, 10 (15) or i, 11 * (15). Tip of pectoral fin reaching slightly beyond half of distance between pectoral and pelvic fins. Pelvic-fin rays i, 7 *(30). Pelvic fin originating at vertical through middle of dorsal-fin base, reaching slightly beyond half the distance between pelvic and anal fins. Anal-fin rays iii, 23 * (16), iii, 24 (6), iii, 25 (6), or iii, 26 (2). Anal-fin origin located posterior to vertical through base of last dorsal-fin ray. Last unbranched anal-fin ray and first to fourth branched rays slightly longer than remaining anal-fin rays. Distal margin of anal fin concave.

Lateral line reaching base of caudal-fin rays. Longitudinal scales in lateral line 44 (6), 45 * (18), or 46 (8). All scales of lateral line pored. Scale rows between lateral line and dorsal-fin origin 7 * (22) or 8 (8); scale rows between lateral line and pelvic-fin origin 3 * (18) or 4 (12). Predorsal scales 10 (9) or 11 * (5), arranged in a regular series. Scale rows around caudal peduncle 15 (5) or 16 * (3). Precaudal vertebrae 19 (5); caudal vertebrae 22 (1) or 23 (4); total vertebrae 41 (1) or 42 (4). Supraneurals 7 (4). First dorsal fin pterygiophore located between 11 th and 12 th vertebrae. Gill rakers of first gill arch 16 (5): 2 (5) hypobranchial, 7 (5) ceratobranchial, 1 (5) on cartilage between ceratobranchial and epibranchial, 6 (5) epibranchial. Gill rakers setiform. Branchiostegal rays 5: 4 (5) on ceratohyal and 1 (2) on epihyal.

Color in alcohol. Overall ground coloration of body dusky brown to yellowish. Dorsal profile of head and snout dark. Infraorbitals, maxillary, and ventral region of opercle silver. Infraorbital 5 and dorsal portion of opercle with scattered chromatophores. Lips and anterior portion of maxilla with dense concentration of chromatophores. Gular region light. Dorsolateral region of body darkened. Scales of lateral region of body with chromatophores concentrated on posterior borders. Two humeral spots present; first humeral spot conspicuous, vertically elongated, extending over three rows of scales above lateral line and horizontally over two rows of scales; second humeral spot inconspicuous, vertically elongated; its form resembling the number 3. Dorsal-fin rays darkened from base to mid-section, light at distal portion. Black adipose fin, but hyaline along its base. Caudal fin with concentrated chromatophores on half nearest most external rays of ventral and dorsal lobes. Pectoral, pelvic, and anal fins hyaline, with few scattered chromatophores.

Color in life. General body color reddish on dorsolateral region above lateral line; light grey from lateral line to ventral scale series. Upper portion of head, opercle, intraorbital bones, and maxilla dark grey. Upper margin of orbit red; anterior and posterior margins yellowish. Dorsal fin red from base to mid-length of rays; distally hyaline. Black adipose fin, with narrow hyaline band at base. Caudal fin red at base to mid-length of dorsal and ventral rays; distal region of lobes hyaline. Pectoral and pelvic fins, as well as first anal-fin rays, yellow.

Sexual dimorphism. Mature males bear hooks on the anal, pelvic, and dorsal-fins rays. Dorsal and pelvic-fin hooks are smaller, fewer in number and spine-like. Anal-fin hooks larger and more numerous, present from distal half of the third unbranched ray, decreasing in number and size to 15 th branched ray. Hooks absent in females.

Distribution. Bryconops munduruku   is known from the igarapé Açu, a tributary on the right margin of the Tapajós River, about 10 km from Aveiro, Pará State, Brazil ( Fig. 4 View FIGURE 4 ).

Etymology. The specific epithet is given in allusion to a tribe of Munduruku   Indians denominated Tapajós- Tapera, who settled on the right margin of the Tapajós River, giving rise to what today is the city of Aveiro, the type locality of Bryconops munduruku   . A noun in apposition.

Ecological notes. igarapé Açu presents clear water running over sandy beds. Its headwaters are located within the limits of the Tapajós National Forest and are densely covered by marginal vegetation. Representatives of Bryconops munduruku   were collected in rapid flowing waters among stretches, where it occurs syntopically with Bryconops cf. giacopinii   , Hyphessobrycon cf. agulha   , Hemigrammus   sp., and Moenkhausia comma   .

TABLE 1. Morphometric data of holotype and 30 paratypes of Bryconops munduruku. Holotype is included in the ranges and means. SD = standard deviation.

  Holotype Range Mean SD
Standard Length (mm) 76.6 31.8–96.4 61.4 -
Percents of Standard Length      
Predorsal length 41.4 41.4–50.6 48.8 1.6
Preanal length 66.7 60.4–67.3 65.3 1.4
Prepelvic length 49.0 47.4–52.6 49.8 1.3
Prepectoral length 26.4 25.5–29.1 27.1 0.8
Dorsal-fin base length 13.1 9.8–17.9 14.5 1.4
Dorsal origin to pectoral origin 37.3 31.5–38.5 35.8 1.7
Dorsal origin to pelvic origin 33.7 27.1–35.3 31.9 2.0
Dorsal terminus to anal origin 35.1 27.6–37.8 34.1 2.5
Dorsal terminus to anal origin 28.1 21.5–30.8 27.4 2.2
Dorsal terminus to pelvic origin 33.4 27.7–35.4 32.1 1.9
Dorsal terminus to anal terminus 31.9 26.3–35.3 31.0 1.7
Dorsal terminus to adipose origin 22.1 21.3–26.6 22.9 1.1
Adipose terminus to hypural plate 14.6 11.7–16.0 14.4 1.1
Pectoral origin to pelvic origin 23.8 20.6–25.6 23.2 1.1
Anal-fin base length 25.7 24.6–29.5 27.2 1.2
Anal origin to adipose origin 30.4 27.1–33.0 30.1 1.6
Length of caudal peduncle 12.4 9.6–14.3 12.5 1.0
Adipose origin to base of last anal-fin ray 10.8 10.8–13.5 12.4 0.7
Maxillary length 14.0 13.1–15.7 14.1 0.7
Snout length 8.0 5.9–8.2 6.9 0.6
Horizontal orbit diameter 8.4 7.1–12.0 9.7 1.0
Head length 26.0 22.2–29.2 26.1 1.4
Percents of Head Length      
Tip of snout to tip supraoccipital spine 86.4 81.7–102.7 89.1 4.6
Maxilla to pectoral origin 45.7 44.6–59.8 50.8 3.9
Maxilla to posterior margin of opercle 55.8 51.7–69.3 57.8 3.7
Anterior margin of orbit to maxilla 38.2 32.6–46.7 39.2 2.7
Posterior margin of orbit to opercle 41.0 31.3–48.7 36.7 3.9
Maxillary length 53.8 48.5–60.7 54.0 2.1
Snout length 30.7 21.5–32.0 26.3 2.2
Horizontal orbit diameter 32.2 32.2–44.7 7.5 2.8
INPA

Instituto Nacional de Pesquisas da Amazonia

MCP

Pontificia Universidade Catolica do Rio Grande do Sul