Hyphessobrycon langeanii,

Lima, Flávio C. T. & Moreira, Cristiano R., 2003, Three new species of Hyphessobrycon (Characiformes: Characidae) from the upper rio Araguaia basin in Brazil, Neotropical Ichthyology 1 (1), pp. 21-33: 22-25

publication ID

http://doi.org/ 10.1590/S1679-62252003000100003

publication LSID

lsid:zoobank.org:pub:97088D40-7832-43E4-8CB7-6DCB9AD317F7

DOI

http://doi.org/10.5281/zenodo.5070220

persistent identifier

http://treatment.plazi.org/id/3AA99B23-86C0-402F-B056-0F499DFD1474

taxon LSID

lsid:zoobank.org:act:3AA99B23-86C0-402F-B056-0F499DFD1474

treatment provided by

Carolina

scientific name

Hyphessobrycon langeanii
status

new species

Hyphessobrycon langeanii  , new species Figs. 1 - 4View FigView FigView FigView Fig

Holotype. MZUSP 75127View Materials (50.4 mm SL): Brazil, Mato Grosso, município de Alto Araguaia, córrego Mosquito, km 476.3 of Ferronorte railroad, 17°25’8”S, 53°13’60”W; C. R. Moreira & F.C. T. Lima, 19 May 2001.GoogleMaps 

Paratypes. All localities in Brazil, Mato Grosso, município de Alto Araguaia, unless noted otherwise  : MZUSP 73313View Materials (166, 8 cs, 15.4-58.5 mmSL)  ; MCZ 162370View Materials (5,29.5-31.8 mmSL)  ; USNM 371922View Materials (5, 26.3-31.8 mm SL);DZSJRP 5467 (5,28.7-34.0 mm SL)  ; ZUEC 6174View Materials (5,26.7- 31.7 mm SL); samedataasholotype  . MZUSP 73322View Materials (97, 12.8-34.8 mm SL), córrego do Sapinho, km 474.4 of Ferronorte railroad, 17°25’55”S, 53°14’34”W; CGoogleMaps  . R. Moreira & F.C  . T. Lima , 19May 2001  . MZUSP 73256View Materials (259, 8.1-34.3 mm SL)  ; MNRJ 24780View Materials (5, 22.5-30.4 mm SL); córrego Gordura, km 491.4 of Ferronorte railroad, 17°18’20”S, 53°16’22”W; CGoogleMaps  . R. Moreira & F.C  . T. Lima , 15 May 2001  . MZUSP 73272View Materials (27,14.1-37.7 mmSL), córrego Boiadeiro, km 487.08 of Ferronorte railroad, 17°20’1”S, 53°14’53”W; CGoogleMaps  . R. Moreira & F.C  . T. Lima , 16 May 2001  . MZUSP 73362View Materials (43, 14.6-29.0 mm SL), córrego do Rancho, below Lagoa do Veado ; 17°16’12”S, 53°24’52”W; CGoogleMaps  . R. Moreira & F.C  . T. Lima , 22 May 2001  . MZUSP 73286View Materials (6, 23.1-32.6mm SL), córrego Jaguatirica, km 496.46 of Ferronorte railroad, 17°16’26”S, 53°17’49”W; CGoogleMaps  . R. Moreira & F.C  . T. Lima , 17 May 2001  . MZUSP 73309View Materials (30, 15.5-32.1 mm SL), córrego Bandeira, km 478.35 of Ferronorte railroad, 17°24’5”S, 53°13’32”W; CGoogleMaps  . R. Moreira & F.C  . T. Lima , 18 May 2001  . MZUSP 41405View Materials (62, 13.6-29.0 mm SL), córrego do Rancho (headwaters) at swamp close to the road, c. 17°16’S, 53°24’W; L. P.S. Portugal & F. Langeani, 8 March 1989GoogleMaps  . MNRJ 20351View Materials (2, 21.7-24.0 mm SL), córrego do Rancho , BR-364, 17°12’48”S, 53°20’17”W; F.A.G. Melo, P.A. Buckup and MGoogleMaps  . R.S. Melo , 13 Feb 2000  . MZUSP 41451View Materials (99, 15.8-32.3 mm SL), Goiás, município de Santa Rita do Araguaia, córrego Empantanado , fazenda “Heral” (Herval in a map consulted) (c. 17°32’S, 53°11’W); L. P.S. Portugal & F. Langeani, 7 February 1989GoogleMaps  .

Diagnosis. Hyphessobrycon langeanii  can be distinguished from all congeners by the presence of a single well-defined, round to horizontally oval humeral spot, similar to the one found in species of the Astyanax bimaculatus (Linnaeus)  complex (vs. humeral spot absent, double, or variously developed, never round to horizontally oval). It can also be distinguished from its congeners, except H. reticulatus Ellis  , by the combination of a reticulate dark pigmentation pattern, a broad, horizontally-elongate caudal-peduncle blotch, a narrow dark stripe extending along the central caudal-fin rays, 5 or 6 horizontal scale rows between the dorsal-fin origin and the lateral line, 4 or 5 horizontal scale rows between the lateral line and the pelvic-fin origin, and 15-20 branched anal-fin rays. Hyphessobrycon langeanii  can be distinguished from H. reticulatus  by the possession of a conspicuous, dark round to oval humeral spot (vs. relatively faint, vertically-elongate humeral spot), a horizontally-elongate caudal-peduncle blotch (vs. vertically-elongate caudal-peduncle blotch), the midlateral dark stripe relatively wide and faint (vs. midlateral dark stripe extremely narrow and well-defined), and infraorbitals 3 and 4 co-ossified (vs. separated).

Description. Morphometric data of the holotype and paratypes are presented in Table 1. Body compressed, moderately slender, greatest body depth at pelvic-fin origin. Dorsal profile of head convex from upper lip to vertical through middle of orbit; slightly concave from latter point to tip of supraoccipital spine. Predorsal profile of body convex, dorsal-fin base posteroventrally inclined, straight to slightly convex in smaller individuals (less than 50 mm SL), and convex in larger specimens (see Figs. 2-3View FigView Fig). Body profile straight to convex from end of base of dorsal fin to adipose fin; slightly concave between latter point to origin of dorsalmost procurrent caudal-fin ray. Ventral profile of head and body convex from lower lip to vertical through pectoral-fin insertion; slightly convex from latter point to pelvic-fin insertion. Ventral profile between pelvic-fin insertion and anal-fin origin straight. Body profile along anal-fin base straight to slightly convex and posterodorsally slanted. Ventral profile of caudal peduncle slightly concave.

Jaws equal, mouth terminal.Maxilla reaching middle of orbit. Premaxillary teeth in two rows ( Fig. 4View Fig). Outer row with 2(2), 3(16), or 4*(45) uni- to tricuspid teeth. Inner row with 4(8) tetrato hexacuspid teeth. Maxilla with 1(8) tri- to pentacuspid tooth. Dentary with 4(8) large, tetra- to heptacuspid teeth followed by 4(1), 5(5), 6(1), or 7(1) smaller uni- to tricuspid teeth.

Scales cycloid, with few radii. Lateral line incompletely pored, with 6(4),7(6), 8*(13), 9(18), 10(11), 11(3), or12(1)perforated scales. Lateralseriesscalesincludingperforatedscales 30(1), 31(6), 32(17), 33*(16), 34(10), 35(5), or 36(1). Horizontal scale rows between dorsal-fin origin and lateral line 5(7) or 6*(49), not including scale of predorsal series situated just anterior to first dorsal-fin ray. Horizontal scale rows between lateral line and pelvic-fin insertion 4*(53) or 5(3). Predorsal scales 10*(8), 11(33), 12(13), or 13(2). Circumpeduncular scales 12(10), 13*(26), or 14(20).Single row of 5-7 scales covering base of anterior most anal-fin rays.

50.4 mm SL, Brazil, Mato Grosso, município de Alto Araguaia, Dorsal-fin rays typically ii,9, ii, 8 in one specimen. Dorsalfin origin at middle of standard length. Base of last dorsal-fin ray at vertical through anal-fin origin. First dorsal-fin pterygiophore inserting behind neural spine of 10th(2) or 11th(6) vertebra. Adipose fin present, but vestigial in one specimen. Anal-fin rays iii,15(1), 16(2), 17(11), 18*(28), 19(10), or 20(4). First anal-fin pterygiophore inserting behind hemal spine of 16th(5) or 17th(2) vertebra. Pectoral-fin rays i,10(14), 11*(22), 12(19), or 13(1). Tip of pectoral fin reaching vertical through pelvic-fin insertion. Pelvic-fin rays i,6*(3) or i,7(53). Caudal fin forked, lobes rounded, and similar in size. Principal caudal-fin rays 10+9(8). Ten (2), 11(1), 12(1), or 13(3) dorsal procurrent caudal-fin rays, and 9(1), 10(3), 11(2), or 12(1) ventral procurrent caudal-fin rays. First gill arch with 5(1), or 6(7) epibranchial, 7(5), or 8(3) ceratobranchial, 1(8) on cartilage between ceratobranchial and epibranchial, and 1(2), or 2(6) hypobranchial gill-rakers. Four (8) branchiostegal rays, 3(8) on anterior ceratohyal, and 1(8) on posterior ceratohyal. Vertebrae 31(1), 32(3), 33(3), or 34(1). Supraneurals 4(1), or 5(7).

Color in alcohol. Ground color light beige. Guanine present on opercle, infraorbitals, and sides of body. Dark chromatophores densely concentrated on dorsal surface of head, and anterior surface of lower jaw. Small, dark chromatophores present on maxilla, ventral margin of orbit, and first and second infraorbitals; remaining infraorbitals with larger and more scattered dark chromatophores. Ventral portion of head pale, almost devoid of dark chromatophores. Dorsal midline of body with dense concentration of dark chromatophores. Dark chromatophores concentrated mainly on posterior margin of scales of dorsolateral portion of body, resulting in a reticulate pattern. Ventrolateral portion of body with fewer dark chromatophores, present mainly on posterior margin of scales. Humeral spot well-defined, black, and round to horizontally oval. Thin vertical lines extend posterodorsally and anteroventrally from humeral spot. Narrow dark, midlateral stripe running from immediately posterior to humeral spot to caudal-peduncle blotch. Caudal-peduncle blotch large, welldefined, and horizontally-elongate, its depth ranging from half to two-thirds of caudal peduncle depth (compare Figs.1- 3View FigView FigView Fig; notice that Fig. 2View Fig is slightly overexposed and consequently caudal peduncle blotch is not so conspicuous). Narrow, dark stripe on three middle caudal-fin rays running from caudalpeduncle blotch to distal margin of fin. Remaining portions of caudal fin with scattered dark chromatophores. Dorsal and anal fins hyaline, with small dark chromatophores scattered on interradial fin membranes; chromatophores more concentrated on distal portion of five anterior dorsal-fin rays, and distal margin of anal fin. Pectoral and pelvic fins almost hyaline, with few dark chromatophores. Adipose fin dusky.

Color in life. Description based on three photographed specimens (MZUSP 73272, 2 ex, 31.8-37.7 mm SL; MZUSP 73313, 1 ex, 58.5 mm SL; Figs.2-3View FigView Fig). Ground color beige. Sides of head, and body golden. All fins, except pelvic fin, yellow. Pelvic fin and anterior portion of anal fin orange.

might indicate a tolerance of broader ecological conditions by Hyphessobrycon langeanii  than is the case of its congeners in the upper rio Araguaia (see “Ecological notes” of H. eilyos  and H. weitzmanorum  , below).

Stomach contents of two cleared and stained individuals yielded ants, a beetle, chironomid larvae, unidentified Microcrustacea, diatoms and filamentous algae.

Etymology. The new species is named after our colleague Francisco Langeani, who first collected the new species.

Table 1. Morphometric data for Hyphessobrycon langeanii. Measurements based on the holotype (MZUSP 75127) and 55 paratypes (MZUSP 41405, 1 ex.; MZUSP 41451, 7 ex.; MZUSP 73256, 2 ex.; MZUSP 73272, 6 ex.; MZUSP 73309, 2 ex.; MZUSP 73313, 30 ex.; MZUSP73322, 8 ex.).

holotype n range mean
Standard length (mm) 50.4 56 26.7-58.5 -
Percents of standard length        
Depth at dorsal-fin origin 35.1 56 32.4-38.5 35.3
Snout to dorsal-fin origin 53.8 56 52.6-58.4 55.9
Snout to pectoral-fin origin 28.8 56 27.0-31.1 28.9
Snout to pelvic-fin origin 48.4 56 46.0-51.3 48.6
Snout to anal-fin origin 66.7 56 62.2-67.9 65.5
Caudal peduncle depth 11.3 56 10.2-13.5 11.7
Caudal peduncle length 14.1 56 11.1-16.7 13.9
Pectoral-fin length 16.7 56 16.7-21.1 18.7
Pelvic-fin length 15.5 56 12.1-19.2 16.5
Dorsal-fin base length 12.9 56 10.3-14.5 12.9
Dorsal fin height 24.2 55 22.5-28.2 26.0
Anal-fin base length 24.4 56 21.8-28.5 25.1
Anal-fin lobe length 17.1 54 14.2-20.3 17.5
Eye to dorsal-fin origin 41.7 56 39.7-44.7 42.3
Dorsal-fin origin to caudal peduncle 51.4 56 46.5-53.1 49.9
Bony head length 28.4 56 26.8-31.1 29.2
Percents of head length
Horizontal eye diameter 27.3 56 24.4-37.5 32.5
Snout length 25.2 56 19.5-26.9 23.0
Least interorbital width 35.0 56 29.9-37.3 33.3
Upper jaw length 41.3 56 37.5-47.0 42.5
R

Departamento de Geologia, Universidad de Chile

T

Tavera, Department of Geology and Geophysics