Brycon insignis Steindachner, 1877

Lima, Flávio C. T., 2017, A revision of the cis-andean species of the genus Brycon Müller & Troschel (Characiformes: Characidae), Zootaxa 4222 (1), pp. 1-189 : 36-42

Brycon insignis Steindachner, 1877

( Figs. 22–24 )

Brycon insignis Steindachner, 1877: 587 –591, pl. 4, figs.1, 1a (not 2, 2a; see Steindachner, 1879c: 50, footnote: “Taf. IV, Fig.1 [nicht Fig. 2 …]) (Type locality “Rio Parahyba bei Campos und Mendez; Rio Jequitinhonha”, restricted herein to “Rio Parahyba bei Campos und Mendez”); Steindachner, 1879c: 50 (as a possible synonym of B. devillei ); Howes, 1982: 24, 32 (discussion; possible synonym with B. devillei ); Almeida-Toledo et al., 1996: 36, 38 (karyotype); Menezes et al., 2007: 110 (photograph; distribution, ecology, conservation status); Hilsdorf et al., 2008: 48–50, 277 (photo) (distribution, ecology, conservation); Matsumoto & Hilsdorf, 2009: 395 –402 (Brazil, rio Paraíba do Sul basin; genetic variation); Travenzoli et al., 2015: 6, 8–11, 14 (Rio Paraíba do Sul, Itaocara, Rio de Janeiro; cytogenetics, phylogenetics relationships, molecular taxonomy)..

Catabasis acuminatus Eigenmann & Norris, 1900: 358 (Type locality “Rio Tieté”); Roberts, 1969: 437 –438 (holotype, discussion).

Megalobrycon piabanha A. Miranda-Ribeiro, 1902: 5 (Type locality “Cataguazes, rio Pomba”).

Megalobrycon piabagna: A. Miranda-Ribeiro, 1905: 153 –154 (rio Pomba, Minas Gerais).

Brycon falcatus (non Müller & Troschel): Pellegrin , 1909b: 149 (“ Rio Grande ”; specimen MNHN 1909–214 examined).

Megalobrycon piabanga (sic): Magalhães, 1931: 155 –156, fig. 81 (Rio Paraíba do Sul; natural history).

Brycon acuminatus: Howes, 1982: 4 –6 (Taubaté, Rio Paraíba do Sul; discussion).

Brycon sp.: Bizerril, 1995: 69 (Rio de Janeiro, rio São João).

Brycon devillei (non Castelnau): Araújo, 1996: 116, 119, 121 (Rio de Janeiro, rio Paraíba do Sul, São Fidélis).

Brycon opalinus (non Cuvier): Bizerril & Primo, 2001: 54–56, 201, 208, 231, 255, 259, 263, fig. 27 (Rio de Janeiro: rio São João; rio Macaé; Lagoa Feia at rio Ururaí and rio Macabu; rio Itabapoana; rio Paraíba do Sul and its tributaries rio Muriaé, rio Pomba, and rio Imbé at Lagoa de Cima); Bidegain et al., 2002: 81, 90 (Lagoa Feia system, Rio de Janeiro; occurence, importance in fisheries).

Diagnosis. Brycon insignis can be diagnosed from all remaining cis-andean Brycon species, with the exception of B. stolzmanni , B. coxeyi , B. coquenani , B. vermelha , B. howesi , B. dulcis , B. ferox , B. vonoi , B. opalinus , and B. nattereri by possessing a color pattern consisting in a humeral blotch and a caudal peduncle blotch, without body stripes or other obvious color markings on caudal and anal-fins (vs. body stripes and caudal/anal fin color markings present) (see Fig. 5 ). Brycon insignis can be diagnosed from these species, with the exception of B. howesi , B. vermelha , and B. coquenani , by possessing a fifth infraorbital bone considerably wider than high (vs. fifth infraorbital bone about as wide as high; see Fig. 6 ). Brycon insignis can be diagnosed from B. coquenani by possessing a higher head (63.1–75.9 % of head length, mean 68.9, vs. 59.8–64.9 %, mean 61.4, in B. coquenani ), by possessing pointed tri- to pentacuspidate dentary teeth, with moderately developed lateral cusps (vs. pointed, trito tetracuspidate dentary teeth, with lateral cusps poorly developed; see, however, the item “Remarks”, below, on individuals formely assigned to Catabasis acuminatus ), and by mature males displaying hooks only in anal fin (vs. mature males displaying hooks in all rayed fins, including caudal fin). Brycon insignis can be distinguished from B. vermelha by presenting darkened dorsal, caudal, and anal-fins in both living and preserved specimens (vs. dorsal, caudal, and anal-fins reddish in living, clear in preserved, B. vermelha specimens). Brycon insignis can be distiguished from Brycon howesi by possessing 51–65, modally 58 lateral line scales (vs. 46–50, modally 49 in B. howesi ), 9–11, modally 10 horizontal scale rows between the dorsal-fin origin and the lateral line (vs. 7–9, modally 8 in B. howesi ), 4–7, modally 5 horizontal scales rows between the lateral line and pelvic fin (vs. 3–5, modally 4 in B. howesi ) and a pointed snout in profile in B. insignis (vs. snout pointed, but rounder, in B. howesi ). For more comparisons among Brycon insignis , B. vermelha , and B. howesi , see the item “Remarks” of these latter two species.

Description. Morphometric data are presented in Table 5 . Large-sized species, largest examined specimen 493.0 mm SL. Body moderately slender. Largest body height slightly ahead of dorsal-fin origin. Dorsal body profile slightly convex from upper lip margin to vertical through anterior naris, moderately convex from latter point to basis of supraoccipital process, and moderately convex from latter point to dorsal-fin origin, straight along dorsal-fin basis, and straight to slightly convex from dorsal-fin basis to adipose-fin origin. Dorsal profile of caudal peduncle slightly concave. Ventral profile slightly convex from lower lip to pelvic-fin insertion, straight to slightly convex from this point to anal-fin origin and approximately straight along anal-fin base. Ventral profile of caudal peduncle slightly concave.

Head profile conspicuously acute anteriorly, mouth terminal. Jaws anisognathous, premaxillary projecting slightly relative to dentary, outer row of premaxillary teeth and in some specimens also second row exposed when mouth is closed. Maxillary long, extending posteriorly to slightly posterior to middle of pupil. Adipose eyelid well developed. Premaxillary teeth in three rows; teeth of third row largest. Five (1), 7 (6), 8 (12), 9 (13), 10 (9), 11 (6) ou 12 (3) tricuspidate teeth in outer series. Three (1), 4 (21), 5 (18), 6 (6), or 7 (1) tri- to pentacuspidate teeth in second, inner premaxillary row, plus 1 (14), 2 (23), or 3 (12) tricuspidate teeth between the first and third rows. Two teeth in third premaxillary row, medial teeth largest, symphyseal teeth smaller, slightly tilted towards each other, both pentacuspidate. Maxillary with distal portion distinctly expanded and rounded in profile. Eighteen to 33 maxillary teeth, slightly smaller than teeth of first premaxillary row, anterior teeth tricuspidate, posterior teeth unicuspidate. Dentary with 9 (1), 10 (1), 11 (4), 12 (7), 13 (5), 14 (10), 15 (10), 16 (6), or 17 (3) 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, tetra, tri- to unicuspidate. Inner (lingual) series consisting of a small, single unicuspid symphyseal tooth, situated immediately posterior to symphyseal dentary teeth of main series, plus row of 23–37 small, unicuspidate teeth, originating on lingual crest of dentary replacement trench at level of the fourth to sixth teeth of main series. Inner symphyseal teeth absent in 6 out of 19 specimens examined for this character. Larger specimen displaying symphyseal teeth 220.3 mm SL (MZUSP 2091); specimens larger than 230 mm SL (MCZ 21112, MZUSP 103029, MZUSP 88515, MZUSP 19128) lacking symphyseal teeth. A single specimen smaller than 220 mm SL lacking symphyseal teeth (MNRJ 4716, 138.3 mm SL).

Scales cycloid. Lateral line complete, from supracleithrum to caudal-fin base. Fifty-one (2), 52 (2), 53 (5), 54 (6), 55 (5), 56 (8), 57 (5), 58 (9), 59 (5), 60 (2), 61 (2), 62 (2), 63 (4) ou 65 (1) scales in lateral line series. Laterosensory tube simple in small (<200 mm SL) specimens, deflected upwards in the first 5–6 scales, downwards in the remaining lateral-line scales. Larger specimens (> 200 mm SL) with branched tubules, mostly bifurcated in middle-sized (230–270 mm SL) specimens but some scales with 3–5 tubules in the larger (> 290 mm SL) specimens examined. Horizontal scale rows between dorsal-fin origin and lateral line 9 (9), 10 (25), or 11 (22). Horizontal scale rows between lateral line and pelvic-fin 4 (7), 5 (27), 6 (17), or 7 (3). Circumpeduncular scales 16 (3), 17 (2), 18 (9), 19 (10), 20 (12), 21 (12), or 22 (3).

Dorsal-fin rays ii, 9. Dorsal fin origin slightly ahead of middle of SL. First dorsal-fin pterygiophore inserting behind neural spine of 13th vertebra. Anal-fin rays iii (not including first, small unbranched ray only visible in the cs specimen), 21 (2), 22 (2), 23 (10), 24 (9), 25 (12), 26 (17), or 27 (5). First anal-fin pterygiophore inserting behind haemal spine of 24th vertebra. Last unbranched and anterior 3–4 branched anal-fin rays longer, remaining rays progressively shorter towards anal-fin end. Anal fin displaying numerous (c. 18–22 per fin-ray main branch) middle-sized hooks on last unbranched and posterior main branch of branched rays 10–20, associated with dense, gelatinous tissue in six specimens (MZUSP 2091, 209.0– 220.3 mm SL; MZUSP 79092, 187.2 mm SL; MZUSP 88515, 235.0–247.0 mm SL; MZUSP 107280, 260.0 mm SL). A single hook per ray segment. Sheath of scales covering basis of anal-fin rays composed of two scale rows, lower scale row formed by 25–30 rectangular scales. Pectoral-fin rays i, 11 (1), 12 (10), 13 (27), 14 (15), or 15 (1). Pelvic-fin rays i,7. Main caudal-fin rays 10/9. Caudal fin forked, lobes slightly pointed.

Four branchiostegal rays, three on anterior ceratohyal and one on posterior ceratohyal. First branchial arch with 11 (2), 12 (6), 13 (10), 14 (12), 15 (3), or 16 (1) lower, 1 at angle, and 11 (4), 12 (14), 13 (12), 14 (3), or 17 (1) upper gill rakers. Vertebrae 45 (2). Supraneurals 9 (1).

Coloration in alcohol. Description based on wild-caught, recently collected specimens (MZUSP 88515 and MZUSP 103045); the majority of remaining examined specimens faded, either due to a long period of conservation (> 60 years) or for being originally captive, stocked specimens raised in clear-water, sun-lit ponds. Top of head, snout, supraorbital, sixth infraorbital, upper portion of fifth infraorbital, and dorsal portion of body dark-brown. Second, third, and fourth infraorbitals light brown, with a silvery hue. Opercle mainly silvery, with some lightbrown tinge. Dentary, maxillary, gular area and lower portion of body clear, with a cream tinge. Lateral portion of body light-grey, silvery in specimens retaining a considerable amount of guanine (e.g., MCZ 21112, MZUSP 62746). Scales above lateral line on lateral surfaces of body with dark pigmentation concentrated on scales margins, forming a tenuous reticulated pattern in specimens MZUSP 88515 and MZUSP 103045. Humeral blotch present, moderately conspicuous, approximately rounded in shape, situated immediately above lateral line, its anterior margin at level of second to third, extending longitudinally to posterior margin of fourth to fifth lateral line scales, and vertically less than one scale high. Lateral surfaces of body above lateral line, and posterior to dorsalfin, presenting longitudinal stripes formed by dark pigmentation on central portion of scales in specimens MZUSP 88515 and MZUSP 103045. Large, moderately conspicuous, oval-shaped caudal peduncle blotch, extending along 8–11 last lateral-line scales. All rayed fins with a considerable amount of dark pigmentation at the interradial membranes (discernible even in some severely faded specimens, e.g., MZUSP 2091), imparting a overall dark coloration to these fins. Caudal-fin with a poorly discernible, roughly V-shaped blotch, formed by dark pigmentantion situated on outer caudal-fin rays. Adipose fin light-grey to light-brown.

Color in life. Description based on a specimen photographed alive at the CESP-Paraibuna fish hatchery and from photographs of specimens MZUSP 103045, immediately before fixation. Top of head and snout dark. Dentary and maxillary clear. Dorsal portion of body plumbeous. Opercle, infraorbital bones, and lateral portion of body silvery. Humeral blotch inconspicuous; caudal peduncle blotch moderately conspicuous. All fins, except adipose fin, darkened. Caudal fin with outer fin-rays dark, forming a roughly V-shaped blotch.

Sexual dimorphism. Five specimens (MZUSP 2091, 209.0– 220.3 mm SL; MZUSP 79092, 187.2 mm SL; MZUSP 88515, 235.0–247.0 mm SL; MZUSP 107280, 260.0 mm SL) possess anal-fin hooks. Hooks are, however, absent from pelvic- and remaining fins. One specimen (MZUSP 2091) proved to be a male after dissection. At the CESP-Paraibuna fish hatchery, mature males were in fact distinguished from females due to the presence of analfin hooks (L. Girardi, pers. comm, 1999).

Common names. “ Piabanha ”; “piabanha-vermelha” ( Miranda-Ribeiro, 1902: 254); “biririca” (juvenile specimens, rio Itabapoana, V. L.M. Santos, pers. comm.).

Distribution. Known from the rio Paraíba do Sul basin at São Paulo, Rio de Janeiro, and Minas Gerais states, plus several smaller coastal river drainages at Rio de Janeiro state, i.e., rio Guandu, rio Macaé, rio São João, rio Imbé and Lagoa Feia system, and rio Itabapoana, at the border of Rio de Janeiro and Espírito Santos states ( Fig. 25 ). Specimens from the rio Macaé were not examined in the present study, but the species also occurs at this small river system according to Bizerril & Primo (2001). Extirpated from much of its original range (see “Conservation”, below).

Ecological notes. Stomach contents of a dissected specimen (MZUSP 2091) contained a whole, nonmasticated fruit and flowers remains. Bizerril & Primo (2001: 55, as B. opalinus ) reported insects from stomachs of specimens collected at the rio Paraíba do Sul. Magalhães (1931: 156) reported smaller fishes as the main dietary item of B. insignis . Males achieve maturity at the second year of age, with about 20 cm TL, while females mature at the third year of age, at the size of 25 cm TL ( Salgado et al., 1997). Microsatellite anaylsis of populations across the rio Paraíba do Sul basin showed significant differentiation among distinct populations (Matsumoto & Hilsdorf, 2008).

Conservation. Brycon insignis was reported as being a common fish in the rio Paraíba do Sul basin in the past ( Magalhães, 1931). Machado & Abreu (1952) recorded that Brycon insignis was the second more important fish in the commercial fisheries in the rio Paraíba do Sul basin, with annual landings of 15–22 tonnes in the São Paulo portion of the basin alone. The steep decline of the populations of the species, already foreseeing by Magalhães (1931), was due to combination of several factors, the main being water pollution (both sewage and industrial pollution) and deforestation of the riparian forest. The introduction of the dourado, Salminus brasiliensis , into the rio Paraíba do Sul basin in the mid-1950’s decade is also mentioned by older fishermen as an important cause of decline of the species, probably due to competition and/or predation. The last record of Brycon insignis into the portion of the rio Paraíba do Sul basin in São Paulo state was during the late 1980’s decade ( Salgado et al., 1997). The species is still reported as occurring in the middle/lower stretches of the rio Paraíba do Sul basin at the Rio de Janeiro state (e.g., Bizerril & Primo, 2001; G. Sousa per A.W. Hilsdorf, pers. comm.), but some recent catastrophic fish killings due to the leakage of pesticides and other pollutants have occurred in the basin, the latter in November 2008. Brycon insignis was apparently extirpated from two small coastal river systems where it once occurred, the rio Guandu and the rio Macaé. The record for the rio Guandu is based on a single specimen collected at the former Imperial farm at Santa Cruz, during the Thayer Expedition, in 1865 (MCZ 21112). This specimen was labelled as being collected at the rio Grande, which Higuchi (1992) identified as being a small river system draining into the Lago da Tijuca, currently within the urban area of Rio de Janeiro city ( Bizerril & Primo, 2001: 135–136). However, since the latter river lies very far from the Santa Cruz Imperial farm (more than 30 km in a straight line), we believe that the specimen was actually collected in the rio Guandu, a larger river system much closer to the imperial farm and a known locality for other Thayer Expedition specimes (as “Rio Quenda” or “Quendu”). The rio Guandu has been severely altered during the XX century and a continual occurrence of the species in this river system is highly unlikely. As for the rio Macaé, recent collecting efforts in the basin failed in locating the species (M.G. Brito, pers. comm.). Brycon insignis is officially considered as a threatened species in Brazil, under the category “critically endangered” (Hilsdorf, Lima & Matsumoto, 2008). Stocked populations of the species are kept in two fish hatcheries stations at São Paulo and Rio de Janeiro states (CESP-Paraibuna, Paraibuna, and Projeto Piabanha , Itaocara, respectively). There is still a reasonable genetic variability as shown by microsatellite loci in wild Brycon insignis , but considerably little variation in the captive stock of the species (Matsumoto & Hilsdorf, 2009).

Remarks. Steindachner (1877) originally described Brycon insignis based on an unspecified number of syntypes from the “Rio Parahyba bei Campos und Mendez, Rio Jequitinhonha”. There are some discussion in the literature whether syntypes of Steindachner’s species described based on material collected by the Thayer Expedition should be considered as only the specimens present at the NMW collection or should also encompass material deposited at MCZ, which were examined by Steindachner during his stay at Harvard in several periods between April 1870 until his final departure from the United States in December 1873 ( Steindachner, 1875a: 499; Herzig-Straschil, 1997). Schaefer (1997: 49) considered that only specimens deposited at the NMW should be considered types, an opinion that has not been unanimously accepted. For example, Vari (1992: 48) designated a MCZ specimen as the lectotype of Steindachnerina bimaculata , quoting Steindachner’s description of the species where he refers to “numerous specimens… in the Museum at Cambridge” (Steindachner, 1876: 79). There are in fact a few more more references by Steindachner to material deposited at the MCZ, which points out that he has not necessarily relied exclusively on material brought by him to the NMW in his descriptions of species based totally or partially on material collected by the Thayer Expedition (for example, Leporinus mormyrops ; Steindachner, 1875b: 244). A possible compromise solution to this problem would be to recognize, as Vari (1992) did, the MCZ material as typical only in the relatively few descriptions of fishes based on material collected by the Thayer Expedition where Steindachner specifically mentioned specimens from the “Museum zu Cambridge”. With this view in mind, we opted for not considering as belonging to the typical series the specimens deposited at the MCZ belonging to the same original lots from which the material used by Steindachner (1877) in his descriptions of the two Brycon species based on material collected by the Thayer Expedition, B. insignis and B. ferox . We found three lots at the NMW collection which can be assigned as belonging to the syntypical series used by Steindachner (1877): NMW 62925 (2), NMW 62926 (1, 113.5 mm SL), and NMW 62927 (1, 71.6 mm SL). Label information for the lots NMW 62925 and NMW 62926 states only that they were collected at the “Rio Parahyba”, with no further locality information. The specimen NMW 62927 was collected at the “Rio Jequitinhonha”, and actually belong to the species herein described as Brycon howesi (see “Remarks” of this species). In order to dispel any doubts concerning the identity of Brycon insignis , we therefore select the smaller specimen of the lot NMW 62925 (144.8 mm SL), which is the syntype in better overall condition, as the lectotype of Brycon insignis , the remaining syntypes becaming, thus, paralectotypes. As noticed by Steindachner (1879c: 50, footnote), the indication of the plate in Steindachner (1877: 135) is incorrect, Brycon insignis being actually the species portrayed in figures 1 and 1a, figures 2 and 2b referring to B. ferox . Steindachner (1879c: 50) considered Brycon insignis as a synonym of B. devillei , an opinion that prevailed in the literature for a long time (e.g., Howes, 1982). Brycon devillei is considered herein as a species inquirenda (see the item “Remarks” under this species, below).

Megalobrycon piabanha A. Miranda-Ribeiro (1902: 254) was described from the rio Pomba, a tributary of the rio Paraíba do Sul at Minas Gerais state, Brazil, based on a large (520 mm TL) specimen. A little after, the same author ( A. Miranda-Ribeiro, 1905) redescribed and figured the species, unjustifiably ammending its name to Megalobrycon piabagna . Searches in the MNRJ collection failed in locate the holotype of Megalobrycon piabanha . However, the description and illustration given by A. Miranda-Ribeiro (1902, 1904), as well as the provenance of the specimen, leave no doubt that this name represents a junior synonym of Brycon insignis .

Catabasis acuminatus Eigenmann & Norris (1900: 358–359) was described from the “Rio Tieté”, São Paulo state, Brazil. As discussed under the item “Remarks” of the genus Brycon , the genus Catabasis was for a long time considered as possibly related to Salminus ( Eigenmann & Norris, 1900; Roberts, 1969; Géry, 1977). Howes (1982: 4–6), based on the examination of a single specimen (MZUSP 1533), was the first to consider Catabasis merely as a synonym of Brycon . He also considered that Catabasis acuminatus was probably a synonym of B. ferox , a supposition mainly based on the comparison of the specimen available to Howes (1982) with the illustration of Brycon ferox in Steindachner (1877) . As noted above, the indication of the figures in Steindachner (1877, plate 4) are shifted, so what Howes (1982: 28) was in fact suggesting was that Catabasis acuminatus was probably a synonym of Brycon insignis . Catabasis acuminatus was noted by its peculiar dentition, consisting exclusively in unicuspid teeth ( Roberts, 1969: 437–438; Howes, 1982: 4). The only other Brycon species known to possess exclusively unicuspid teeth is Brycon coquenani (see above). However, from the examination of both the specimen identified by Howes (1982) as Brycon acuminatus , as well as the holotype of Catabasis acuminatus (CAS 11894) we were unable to identify any other character differentiating this purported species from B. insignis . Similar-sized, typical Brycon insignis possess teeth with small, poorly developed lateral cusps, a condition not completely dissimilar to the condition found in the specimens assigned to Catabasis acuminatus . We consider the absence of cusps in the specimens assigned to Catabasis acuminatus should be interpreted as constituting intraspecific variation within Brycon insignis , and, thus, that Catabasis acuminatus should be considered a synonym of B. insignis . As for the type-locality of Catabasis acuminatus , said to be at an unspecified locality in the rio Tietê system (rio Paraná basin), no further records for Brycon insignis for the rio Paraná system exist. The rio Tietê is now a highly disturbed river system, its upper reaches heavily polluted by sewage and industrial discharges ( Jorge, 2006), and its middle and lower reaches dammed by a series of hydroelectric reservoirs. Meagre information is available on the ichthyofauna of the rio Tietê prior to the drastic environmental deterioration of this river system (e.g., Ihering, 1929). However, it is quite unlikely that a large fish species, targeted by fishermen like a Brycon species would not have been reported again if really occurring in the rio Tietê basin. We consider that the reported type-locality of Catabasis acuminatus is incorrect, and that the holotype of this nominal species was probably collected somewhere in the rio Paraíba do Sul basin.

Material examined. Type material: NMW 62925:2 (1, 144.8 mm SL): " Rio Parahyba, Jan. 1874; Steindachner don." Lectotype of Brycon insignis Steindachner , by present designation . NMW 62925:1 (1, 167.7 mm SL); NMW 62926 (1, 113.5 mm SL): same data as lectotype. Paralectotypes . CAS 11894 (1, 135.1 mm SL), Brazil, São Paulo, rio Tietê ; H. von Ihering, 1901–1905. Holotype of Catabasis acuminatus Eigenmann & Norris.

Non types: Brazil, São Paulo: MZUSP 51309 (1, 253.7 mm SL) ; MZUSP 62746 (2, 217.9– 310.4 mm SL); MZUSP 42045 (4, 1 cs, 143.1–195.8 mm SL); MZUSP 104939 (1, 493.0 mm SL): CESP-Paraibuna fish hatchery (stocked from specimens collected at Caçapava , rio Paraíba do Sul, c. 23°6’S, 45°43’W) . MZUSP 19128 (1, 365.5 mm SL), Rio Paraíba do Sul, Cachoeira Paulista , c. 22°39’S, 45°00’W ; J.T. Braga, May 1981 . MZUSP 1553 (1, 143.1 mm SL), São Paulo, Taubaté , rio Paraíba do Sul, c. 22°58’S, 45°36’W ; E. Garbe, 1911. CAS 68912 (1, 161.2 mm SL), “ São Paulo ” (no precise locality); collector unknown, 1902

Rio de Janeiro, rio Paraíba do Sul basin: MCZ 21114 (1, 135.3 mm SL) ; MCZ 21115 (4, 130.5– 149.8 mm SL), “ Mendez ” [rio Paraíba do Sul or tributary at Mendes , 22°32'S, 43°44' W] ; C.F. Hartt & E. Copeland, 1865. MCZ 21110 (7, 154.0– 178.5 mm SL): “ Muriahé ” [rio Muriaé at Muriaé , 21°8'S, 42° 23'W]; C.F. Hartt & E.Copeland, 1865 . MCZ 21117 (5, 148.8– 231.6 mm SL), “ Campos ” [Rio Muriaé at Campos dos Goytacazes, 3 miles from town, 21°43’S, 41°22’W]; C.F. Hartt & E. Copeland, 1865 . CAS 68832 (1, 258.0 mm SL), rio Paraíba do Sul drainage [precise locality uncertain]; Bourget, date not specified [1865–1866] . MNRJ 18246 (1, 198.8 mm SL), Itaperuna, Valão de São Domingos (tributary of rio Muriaé , rio Paraíba do Sul basin, 21°16'S, 41°46'W; D.F. Moraes Jr. et al., 22 Feb 1990. MNRJ 11226 (1, 101.8 mm SL), Itaperuna, córrego do Toiama, trib . Rio Muriaé, road BR-393 (Bom Jesus do Itabapoana-Santo Antônio de Pádua), c. 21°14'0''S, 41°55'30''W; D.F. Moraes Jr., G.W. Nunan & L.C. Alvarenga, 15 Jan 1982 . MNRJ 4761 (1, 138.3 mm SL), Fazenda da Salgada and São José, between Itaperuna and Miracema; A.L. Carvalho, no date . MZUSP 3043 (1, 236.8 mm SL), Cardoso Moreira, rio Muriaé (tributary of rio Paraíba do Sul), 21°29’S, 41°36’W; O. Pinto, July 1941 . MZUSP 103045 (4, 194.5–259.0 mm SL): Campos dos Goytacazes, Rio Muriaé, near its mouth, c. 21°42’S, 42°31’W ; collector not especified, 2002. MNHN 1909-214 (1, 287.7 mm SL): Rio Grande (tributary of rio Paraíba do Sul), c. 21°37’S, 41°49’W ; C. Jobert, c. 1878. MZUSP 79088 (2, 141.7– 148.3 mm SL); MZUSP 79091 (1, 146.5 mm SL): Fish hatchery, Projeto Piabanha , Itaocara (stocked from specimens collected at the middle rio Paraíba do Sul) . Rio de Janeiro, coastal river systems: MCZ 21112 (1, 232.2 mm SL) , Santa Cruz [rio Grande (Arroio Fundo), in urban Rio de Janeiro, at Fazenda Santa Cruz , 22°53'S, 43°43'W]; D. Pedro II, leg. D. Bourget, April 1865 . MZUSP 88515 (2, 235.0–247.0 mm SL), Silva Jardim, Rio São João, near mouth at Lagoa de Juturnaíba , 22°34'S, 42°18'W; collector not specified, Oct 2005 . MZUSP 103029 (1, 291.0 mm SL), Campos dos Goytacazes, rio Imbé , c. 21°47’S, 41°33’W ; G. Sousa, 2000. MZUSP 79092 (1, 187.2 mm SL), Fish hatchery at Itaocara ( Projeto Piabanha ) (stocked from specimens collected at Campos dos Goytacazes, rio Imbé , c. 21°47'S, 41°33'W) ; G. Souza, no date. MZUSP 2091 (5, 140.3– 220.3 mm SL); CAS 11817 (1, 228.0 mm SL); CAS 11816 (1, 213.0 mm SL); Quiçamã, Lagoa Feia , c. 21°57’S, 41°22’W; E. Garbe, Dec 1911 . MZUSP 107280 (1, 260.0 mm SL): Campos dos Goytacazes, fish market (probably from Lagoa Feia ); O.T. Oyakawa et al., 3 Sept 2004 . Rio de Janeiro / Espírito Santo, rio Itabapoana system: MCZ 21116 (9, 144.0– 191.8 mm SL), Itabapoana [Rio Itabapoana at Itabapoana , 21°17’S, 40°59’W] ; C.F. Hartt & E. Copeland, 1865. MZUSP 79087 (3, 193.5–231.0 mm SL): rio Itabapoana , c. 21°17’S, 40°59’W; F. Daudt, 14 Aug 2002 . Minas Gerais, rio Paraíba do Sul system: ZUEC 6384 (1, 251.0 mm SL): Itamarati de Minas, rio Novo (trib. rio Pomba ), 21°28’36’’S, 42°51’36’’W; D.M. Rosa, Feb 2011.

Figures

FIGURE 1. Ventral view of premaxillary teeth arrangement in Brycon falcatus, MZUSP 94987, 368.7 mm SL. Scale bar: 5 mm.

FIGURE 2. Ventral view of premaxillary teeth arrangement in Brycon howesi, MZUSP 103685, 207.0 mm SL. Scale bar: 2 mm.

FIGURE 5. Diagrammatic representation of the patterns of dark colour markings found among cis-andean Brycon species, represented by selected species. A. Brycon stolzmanni. B. Brycon coxeyi. C. Brycon insignis. D. Brycon nattereri. E. Brycon hilarii. F. Brycon whitei. G. Brycon amazonicus. H. Brycon gouldingi. I. Brycon melanopterus. J-L. Brycon falcatus.

FIGURE 6. Diagrammatic representation of the head profile, maxillary and infraorbitals showing the distinct morphologies found among cis-andean Brycon species, represented by selected species. A. Brycon amazonicus, MZUSP 3815, 152.3 mm SL. B. Brycon insignis, MCZ 21112, 232.2 mm SL. C. Brycon dulcis, MZUSP 1531, 146.6 mm SL. D. Brycon falcatus, MZUSP 3845, 195.1 mm SL. E. Brycon opalinus, MCZ 21123, 210.5 mm SL. F. Brycon orbignyanus, MZUSP 3900, 108.9 mm HL. G. Brycon ferox, MCZ 60934, 310.3 mm SL. H. Brycon orthotaenia, MZUSP 2007, 188.7 mm SL. I. Brycon polylepis, MZUSP 70413, 203.9 mm SL. J. Brycon stolzmanni, UMMZ 185306, 120.0 mm SL.

FIGURE 22. Brycon insignis, lectotype, NMW 62925: 2, 144.8 mm SL: Brazil, Rio de Janeiro, rio Paraíba do Sul.

FIGURE 23. Brycon insignis, MZUSP 103045, 259.0 mm SL: Brazil, Rio de Janeiro, rio Paraíba do Sul.

FIGURE 24. Brycon insignis, MZUSP 62746, 310.4 mm SL: Brazil, São Paulo, rio Paraíba do Sul.

FIGURE 25. Map of eastern Brazil, showing known localities of Brycon insignis (red dots), B. vermelha (grey dots), and B. howesi (black dots; dark star indicates type-locality).

Tables

TABLE 5. Morphometric data of Brycon insignis (A: lectotype, NMW 62925: 2; B: holotype of Catabasis acuminatus, CAS 11894).

	A	B	n	Range	Mean
Standard length (SL)	144.8	135.1	53	113.5–365.5	-
Percentages of standard length
Depth at dorsal-fin origin	26.4	27.5	31	25.0–32.0	28.1
Snout to dorsal-fin origin	54.4	52.3	53	48.7–55.7	53.1
Dorsal-fin base length	10.8	9.3	53	9.3–13.3	11.6
Posterior terminus of dorsal fin to adipose fin	23.0	20.7	53	20.7–25.7	23.3
Posterior terminus of dorsal fin to hypural joint	37.3	34.7	53	32.4–39.9	36.3
Snout to pelvic-fin insertion	48.2	50.0	30	44.4–51.6	47.6
Snout to anal-fin origin	66.3	68.5	52	62.6–70.2	66.7
Anal-fin base length	23.1	-	50	22.5–27.5	24.4
Caudal peduncle length	13.9	10.4	53	10.4–16.1	13.7
Dorsal-fin height	19.6	-	45	16.0–22.1	20.0
Pectoral-fin length	18.1	-	48	15.6–20.9	18.2
Pelvic-fin length	14.4	-	50	11.5–17.1	14.8
Caudal peduncle depth	7.7	7.6	47	7.3–9.3	8.2
Head length	30.0	29.2	53	25.4–32.5	28.0
Percentages of head length
Head height	65.4	63.8	53	63.1–75.9	69.1
Snout length	30.6	-	52	25.6–33.4	29.8
Upper jaw length	50.7	45.8	53	42.9–51.2	48.5
Horizontal eye diameter	22.6	17.0	53	17.0–25.6	21.4
Post-orbital length	49.3	48.1	53	46.8–54.8	50.4
Least interorbital width	28.3	28.1	53	26.3–37.7	32.1