Salminus hilarii Valenciennes, 1850

Lima, Flávio C. T., 2022, Revision of the smaller-sized dorados (Salminus), with comments on the monophyly of the genus and its biogeography (Characiformes: Bryconidae), Zootaxa 5226 (1), pp. 1-66 : 18-29

Salminus hilarii Valenciennes, 1850

( Figs. 8–10 )

Salminus hilarii Valenciennes in Cuvier & Valenciennes, 1850: 64–65 (in part; type locality: “Rio San-Francisco”...“rivières de l’interieur du Brésil ”); Kner, 1860: 51–52 (in part: “Irisanga”, Brazil); Ģnther, 1864: 349–350 (“Rio S. Francisco”, Brazil); Ļtken, 1875a: 227–232 (Rio das Velhas, Minas Gerais, Brazil; comparison with Salminus cuvieri = S. franciscanus ); Ļtken, 1875b: 142 (common name; rio S ã o Francisco, Brazil); Eigenmann, 1916: 91–92 (diagnosis in key; Brazil: “Bom Jardin. Rio Grande above the falls”; Piracicaba; “Sapina”; Salto Avanhandava); Ihering, 1929: 50, 75–76, 81 (Rio Tamanduateí; rio Mogi-Guaçu, S ã o Paulo, Brazil); Magalh ã es, 1931: 202–203, fig. 110 ( Brazil: “Estado de S. Paulo... estado de Minas”; natural history, fisheries); Ihering & Pereira, 1932: 5 (Rio Paranapanema, S ã o Paulo/ Paraná, Brazil; epizooty); Amaral Campos, 1944: 175 ( Brazil, S ã o Paulo: rio Camanducaia, Monte Alegre do Sul); Amaral Campos, 1945: 453 ( Brazil, rio Mogi-Guaçu, Cachoeira de Emas); Menezes, 1953: 358 (occurrence, Brazil, rio Jaguaribe basin; common name); Moraes & Schubart, 1955: 11–12 ( Brazil; distribution across the rio Paraná basin); Paiva, 1959: 1–23 ( Brazil: Ceará, rio Salgado, tributary of rio Jaguaribe, Icó: length-weight relationship, diet); Gomes & Azevedo, 1960: 136, 139 ( Brazil, S ã o Paulo: rio Camanducaia, Monte Alegre do Sul); Schubart, 1962: 27 ( Brazil, S ã o Paulo, rio Mogi-Guaçu); Britski, 1972: 89 ( Brazil, S ã o Paulo, rio Paraná basin); Godoy, 1975: 366–377 ( Brazil, S ã o Paulo, rio Mogi Guaçu; biology, natural history); Britski et al., 1984: 51–52, fig. 48 ( Brazil, Minas Gerais, rio S ã o Francisco, Três Marias dam); Northcote et al., 1985: 2707 ( Brazil, S ã o Paulo, rio Piracicaba basin); Castro & Arcifa, 1987: 495, 497 ( Brazil, S ã o Paulo: Cachoeira reservoir, rio Atibaia); Géry & Lauzanne, 1990: 117, 120, 122 (in part; distribution, lectotype designation); Godinho et al., 1991: 65 ( Brazil, Minas Gerais: rio Tijuco, tributary of rio Paranaíba); Shibatta & Garavello, 1993: 109–115 ( Brazil, upper rio Paraná and rio S ã o Francisco basins; morphometric comparisons); Gurgel & Costa, 1994: 61 (rio Jaguaribe basin, Brazil; occurrence); Agostinho et al., 1997: 184, 203 ( Brazil, Paraná: rio Paraná basin); Alves et al., 1998: 124, 126 ( Brazil, Minas Gerais: Itutinga reservoir, rio Grande); Carvalho et al., 1998: 327 ( Brazil, S ã o Paulo, rio Paranapanema, Jurumirim reservoir; occurrence); Agostinho et al., 1999: 243 ( Brazil, S ã o Paulo: Três Irm ã os dam, rio Tietê, occurrence before and after impoudment); Agostinho & Júlio Jr., 1999: 380 ( Brazil, Paraná and Mato Grosso do Sul, rio Paraná basin); Sato & Godinho, 1999: 410 ( Brazil, Minas Gerais, rio S ã o Francisco); Meschiatti et al., 2000: 139–140 ( Brazil, S ã o Paulo, rio Mogi Guaçu, lago do Diogo; occurrence); Alves & Pompeu, 2001: 183 ( Brazil, Minas Gerais, rio das Velhas); Nakatani et al., 2001: 110–114, fig. 25–26 (Rio Paraná basin, Paraná; eggs and larvae); Shibatta et al., 2002: 415 ( Brazil, Paraná, rio Tibagi basin); Vittar et al., 2002: 1–5 ( Argentina, Misiones, lower rio Iguazú, Iguazú National Park); Agostinho et al., 2003: 33, 57–58 ( Brazil, Paraná: rio Paraná basin, summary informations on biology and habitat); Barrella & Petrere, 2003: 65 ( Brazil, S ã o Paulo, rio Paranapanema, tributary of Jurumirim dam; rio Tietê, Mogi das Cruzes); Smith, 2003: 127, photo ( Brazil, S ã o Paulo: rio Sorocaba, tributary of rio Tietê); López et al., 2003: 19 (Iguazú National Park, below the waterfalls, Argentina; common name); Oliveira & Garavello, 2003: 131–133, 136 ( Brazil, S ã o Paulo: córrego Cabaceiras, rio Mogi Guaçu basin); Andrade et al., 2004: 123–128 ( Brazil, rio S ã o Francisco, Três Marias dam; breeding); Birindelli & Garavello, 2005: 43 ( Brazil, S ã o Paulo: ribeir ã o das Araras, tributary of rio Mogi Guaçu); Cetra & Petrere, 2006: 435 ( Brazil, S ã o Paulo, rio Corumbataí; occurrence); Gomiero & Braga, 2006: 58, 63, fig. 21 ( Brazil, S ã o Paulo, rio Jacaré-Pepira; occurrence); Luz-Agostinho et al., 2006: 64 ( Brazil, Goiás, rio Corumbá; occurrence); Langeani et al., 2007: 185 (upper rio Paraná basin, Brazil; occurrence); Pavanelli et al., 2007: 60 ( Brazil, Goiás, rio Corumbá basin; occurrence); Perez-Junior & Garavello, 2007: 331 ( Brazil, S ã o Paulo, ribeir ã o do Pântano, trib. rio Mogi Guaçu; occurrence); Villares Junior et al., 2007: 407–412 (length-weight relationship, condition fator; Brazil, S ã o Paulo, rio Sorocaba); Apone et al., 2008: 98 (photo), 102 ( Brazil, S ã o Paulo, rio Quilombo, rio Mogi Guaçu basin; occurrence); Honji et al., 2009: 109–121 (upper rio Tietê, S ã o Paulo, Brazil; oocyte development); Meschiatti & Arcifa, 2009: 139 ( Brazil, S ã o Paulo, rio Mogi Guaçu; occurrence); Oliva-Paterna et al., 2009: 361 ( Brazil, S ã o Paulo, rio Paranapanema, Jurumirim reservoir; length-weight relationships); Smith et al., 2009: 1017 ( Brazil, S ã o Paulo, rio Sorocaba; occurrence); Casali et al., 2010: 159–163 ( Brazil, Minas Gerais, rio Grande, Igarapava dam; occurrence in the fish ladder); Esguícero & Arcifa, 2010: 41–51 ( Brazil, S ã o Paulo, rio Jacaré-Guaçu; fragmentation of populations due to damming); Villares Junior, 2011: 288 ( Brazil, S ã o Paulo, rio Tatuí; occurrence); Arcifa & Esguícero, 2012: 719 ( Brazil, S ã o Paulo, rio Paranapanema, Ourinhos dam; occurrence in the fish passage); Domingos et al., 2013: 482–483 ( Brazil, Minas Gerais, rio Itapecerica; occurrence, photo); Oliveira et al., 2013: 264 ( Brazil, S ã o Paulo, rio Ipanema; occurrence); Nobile et al., 2015: 581 ( Brazil, S ã o Paulo, rio Taquari, rio Paranapanema basin; length-weight relationship); Oliveira et al., 2015: 4 ( Brazil, S ã o Paulo, rio Sapucaí-Mirim; occurrence); Silva et al., 2015: 547–553 ( Brazil, rio Grande, rio Tietê, and rio Paranapanema basins; genetic variation); Villares Junior & Goitein, 2015: 574–579 ( Brazil, S ã o Paulo, rio Sorocaba; diet); Cerqueira et al., 2016: 7 ( Brazil, S ã o Paulo, rio Itapetininga; occurrence); Villares Junior & Goitein, 2016: 905–911 (morphometric changes through ontogeny); Ota et al., 2018: 24-25, fig. 6d ( Brazil, Paraná and Mato Grosso do Sul, rio Paraná; short description); Vincentin et al., 2019: 4 ( Brazil, Mato Grosso do Sul, rio Ivinhema; occurrence); Jarduli et al., 2020: 7 ( Brazil, rio Paranapanema; occurrence); Reis et al., 2020: 457 ( Brazil, Paraná; rio Paraná, rio Paranapanema, and rio Piquiri subbasins).

Salmo melanurus Natterer in Kner, 1860: 52 (name not available, published as a synonym of Salminus cuvieri ).

Brycon erythrura Fowler, 1941: 191–192 , fig. 101 (type locality: “Rio Jaguaribe, Orós, Ceará ” [ Brazil]); Myers & Weitzman, 1966: 103 (cited as probably a Salminus ); Howes, 1982: 26 (as a species inquirenda); Géry & Lauzanne, 1990: 116 (as a putative synonym of Salminus hilarii ).

[not Castelnau, 1855: 60–61, pl. 31, fig. 1; Pellegrin, 1909: 157; Pearson, 1924: 49; La Monte, 1935: 8; Fowler, 1943: 243–244; Mago-Leccia, 1970: 73; Saul, 1975: 110; Santos et al., 1984: 41; Ortega & Vari, 1986: 9; Stewart et al., 1987: 29; Ferreira et al., 1988: 344; Barriga, 1991: 27; Lasso, 1992: 13; Begossi & Garavello, 1990: 348; Taphorn, 1992: 321–323; Ribeiro et al., 1995: 330; Winemiller et al., 1996: 23, 32; Taphorn et al., 1997: 74; Salinas-Coy & Agudelo-Córdoba, 2000: 57–58; Silvano et al., 2001: 60–61; Diaz-Sarmiento-Diaz & Alvarez-Léon, 2003: 313; Amaral, 2004: 80; Galacatos et al., 2004: 49; Lasso, 2004: 156–158; Wright & Flecker, 2004: 447, 449; Aloísio et al., 2005: 13; Bogotá-Gregory & MaldonadoOcampo, 2006: 69; Ortega et al., 2006: 103; Lucinda et al., 2007: 77; Maldonado-Ocampo et al., 2008: 173; Garavello et al., 2010: 577, 580; Morales-Betancourt & Lasso, 2011: 253–254; Ortega et al., 2011: 37; Venere & Garutti, 2011: 111; Albrecht et al., 2012: 206; Bartolette et al., 2012: 62; Usma-Oviedo et al., 2013:: 290–291; Bartolette et al., 2017: 10; Dagosta & de Pinna, 2019: 89; Silva et al., 2020: 5; Meza-Vargas et al., 2021: 20]

Diagnosis. Salminus hilarii has the lower scales counts among all Salminus species, although overlapping with the remaining Salminus , except with S. brasiliensis , presenting 54–72, modally 65, lateral-line scales, 9–12, modally 10, horizontal scales between dorsal-fin origin and lateral line and 4–7, modally 5, horizontal scales between lateral line and pelvic fin-insertion (vs. 79–102, modally 96, 14–18, modally 16, and 6–9, modally 8, in S. brasiliensis , 68–82, modally 77, 11–14, modally 12, 6–8, modally 6, in S. franciscanus , 64–81, modally 71, 11–13, modally 12, 5–7, modally 6 in S. affinis , 65–87, modally 75, 11–14, modally 12, and 4–8, modally 6, in S. iquitensis , and 61–74, modally 69, 10–13, modally 11, and 5–7, modally 6, in S. santosi , respectively). Salminus hilarii can be diagnosed from S. affinis , S. iquitensis , and S. santosi by lacking a dark, straight postorbital stripe extending across the contact area between infraorbitals 4 and 5 to upper portion of opercle (vs. presence), and from S. iquitensis , and S. santosi by lacking small stripes present at interradial membranes of caudal fin (vs. presence). Salminus hilarii can be diagnosed from S. franciscanus by presenting second dentary tooth in the outer tooth series roughly of the same size as the remaining teeth (vs. second dentary tooth in the outer tooth series considerably larger than remaining dentary teeth), and by presenting a small central caudal-fin extension (vs. central caudal-fin extension well developed). Additionally, living specimens of Salminus hilarii can be easily diagnosed from living specimens of S. brasiliensis and S. franciscanus by possessing an overall silvery color pattern, with a yellow to red caudal fin, and remaining fins reddish (vs. overall color pattern golden, with orangish fins). See the “Remarks”, below, for an additional discussion about the diagnosis of S. hilarii from its congeners.

Description. Morphometric data presented in Tables 2–3 . Middle-sized species, larger specimen examined 345 mm SL. Body moderately elongated, largest body height at level of dorsal-fin origin. Dorsal profile slightly convex from snout tip to vertical through anterior nostril, straight to slightly concave from later point to tip of supraoccipital process, slightly convex from later point to dorsal-fin origin, straight along dorsal-fin basis, and straight to slightly convex from dorsal-fin terminus to adipose-fin origin. Dorsal profile of caudal peduncle slightly concave. Ventral profile slightly convex from tip of lower jaw to pelvic-fin insertion, straight to slightly convex from later point to anal-fin origin, and approximately straight along anal-fin basis. Ventral profile of caudal peduncle slightly concave.

Head profile acute anteriorly, mouth terminal. Maxillary elongated, extending posteriorly slightly beyond vertical through posterior eye margin in specimens> 240 mm SL, typically not surpassing this limit in smaller specimens. Adipose eyelid well developed. Premaxilla with two teeth rows. Teeth of outer row teeth considerably larger than those of inner series other than for second tooth of inner row. Outer row with 5–12 teeth, approximately equal in size; teeth with distinct, elongate basal portion (shaft), and apical portion (crown). Crown triangular, angles possibly constituting poorly differentiated cusps. Inner tooth row with 7–16 teeth, symphyseal tooth relatively large, second tooth slightly smaller, third and subsequent teeth considerably smaller. Teeth of inner row morphologically similar to those from outer row, except for proportionally shorter shafts and being more massive overall. Middle portion of ventral margin of maxilla slightly concave. Maxilla with 19–45 teeth, similar in shape to those from outer row of premaxilla, but slightly smaller and decreasing very gradually in size posteriorly, with less developed crowns, last teeth roughly conical. Dentary with 18–45 teeth on primary, outer row morphologically similar to those from outer row in premaxilla, and other than first to third teeth, slightly smaller than those on premaxilla, second tooth larger than remaining teeth in specimens <110 mm SL; in larger specimens, second teeth only very slightly larger than remaining teeth. Remaining teeth gradually decreasing in size and presenting less developed crowns. Teeth of outer dentary row, outer premaxilla row, and maxilla with crowns slightly recurved lingually. Inner tooth row with 43–52 conical teeth arranged continuously from symphysis to terminus of inner rim of replacement teeth trench. Teeth at inner row oriented at right angle relative to teeth of primary row, with apices directed lingually.

Scales cycloid. Lateral line complete, extending from supracleithrum to caudal-fin base. Lateral line scales 54(1), 56(1), 57(2), 58(1), 59(1), 60(2), 61(9), 62(15), 63(19), 64(23), 65*(38), 66(34), 67(21), 68(12), 69(13), 70(7), or 72(1). Laterosensory tubes simple, straight or deflected downward. Horizontal scale series between dorsalfin origin and lateral line 9(10), 10(110), 11*(73), or 12(6). Horizontal scale series between lateral line and pelvic fin insertion 4(13), 5(271), 6*(48), or 7(2). Circumpeduncular scales 18*(1), 19(7), 20(50), 21(86), 22(40), 23(10), or 24(1).

Dorsal-fin rays ii, 9, single specimen ii, 8 and two specimens ii, 10. Dorsal-fin origin approximately midway between snout and hypural joint. First dorsal fin pterygiophore inserting behind neural spine of 13 th (1), 14 th (1), or 15 th (3) vertebrae. Anal fin rays iv, 19(1), 20(3), 21(31), 22(63), 23(55), 24*(31), 25(6), 26(1), or 27(1). First anal fin pterygiophore inserting behind hemal spine of 24 th (1), 25 th (2), 26 th (2), or 27 th (1) vertebrae. Last unbranched rays and first to second branched anal-fin rays longer; third to ninth ray gradually shortening, with remaining rays approximately equal in size. Pectoral fin-rays i, 12*(19), 13(94), 14(63), or 15(9). Pelvic-fin rays i, 7, a single specimen i, 6, two specimens i, 8. Principal caudal-fin rays 10/9. Anal fin with small hooks along last unbranched ray and anteriormost 9 th to17 th branched anal-fin rays in 18 specimens ( ANSP 69614–5 , 2 , 132.9 – 137.5 mm SL; CAS 24782 , 2 , 192.0–210.0 mm SL; MZUSP 45271, 243 mm SL, MZUSP 20475 , 2 , 224–226 mm SL, MZUSP 86921, 243 mm SL, MZUSP 20471 , 5 , 216–264 mm SL, MZUSP 3044 , 4 , 165.6 – 216 mm SL, MZUSP 45272 , 1, 211 mm SL). Hooks limited to posterior branch of ray. Pelvic fins with hooks on branched rays 1–6 in the same specimens, limited to posterior branch of ray. Scales sheath composed of two to three horizontal series covering basal portion of anal-fin rays. Caudal fin moderately forked. Laterosensory tube on caudal fin extending to caudal-fin terminus, with dorsally and ventrally oriented side branches along its length. Central caudal-fin extension present, small, discernible in specimens with well-preserved caudal-fin margins, at level of main rays 10–11, where laterosensory tube ends.

Four branchiostegal rays. First gill arch with 12(2), 13(3), 14(5), 15(7), or 16(1) lower gill-rakers, 11(6), 12(6), 13(5), 14(2), or 15(1) upper gill rakers and 1 at angle. Vertebrae 45(2), 46(1), or 47(4). Supraneurals 8(1), 10 (2), or 11(2).

Color in alcohol. Overall color of specimens still retaining guanine grey dorsally, body sides silvery ( Fig. 9A ); specimens lacking guanine light brown dorsally, with body sides beige ( Fig. 9B ). Top of head (including supraorbital), snout and anterior portion of maxilla brown; remaining infraorbitals and opercle silvery in specimens retaining guanine. Maxilla, gular area and dentary light brown. Humeral blotch present, little conspicuous, oval-shaped, horizontally elongated, formed by pigmentation subjacent to scales, lying immediately above lateral line, at level of anteriormost three scales. Narrow, straight dark stripes extending along trunk, formed by dark chromatophores concentrated at central-distal portion of each scale. Stripes present across all trunk, more conspicuous dorsally. Broad dark stripe across caudal peduncle, starting at level of fourth to seventh last scales, and gradually broadening and becoming more intense towards caudal-peduncle terminus. Caudal-peduncle stripe extending into distal portion of 4–5 middle caudal-fin rays. All fins clear, pectoral and pelvic fins almost devoid of small dark chromatophores, dorsal and anal fins with few scattered dark chromatophores, and adipose fin finely dotted with tiny dark chromatophores.

Color in life. Description based on pictures of a specimen from the Furnas reservoir, upper rio Grande, one from the rio Pardo, both provided by A.K. Zeinad, from a freshly collected specimen (MZUSP 86921, 329 mm SL), provided by J.C. Nolasco, and from several specimens collected at the rio Paraopeba and rio das Velhas (rio S ã o Francisco basin) provided by C.B.M. Alves ( Fig. 10 ). Sides of body clear, with silvery hue; dorsum and top of head grey, ventral area whitish. Reddish to golden irregular blotches present on central portion of opercle and/or infraorbital bones. Caudal fin with central rays above and below middle dark stripe, and distal portion, red (specimens from the rio Paraná basin; Fig. 10A–B ) or yellow, with mid- to distal portions reddish (specimens from the rio S ã o Francisco basin; Fig. 10C ). Pectoral and pelvic fins ranging from hyaline ( Fig. 10A–B ) to reddish ( Fig. 10C ). Dorsal, and anal fins ranging from hyaline ( Fig. 10A–B ) to presenting some yellow/reddish pigmentation ( Fig. 10C ). Adipose fin grey. Dark pigmentation similar to preserved specimens except for being less conspicuous.

Geographic variation. The comparison of extensive material of Salminus hilarii from both the rio Paraná and rio S ã o Francisco basins did not revealed any distinction in either morphometric or meristic features, with a complete overlap in all characters analysed (see Table 3 , for a comparison of morphometric data among all three populations of the species). There is a putative slight difference in color pattern in life between the populations of the rio Paraná and the rio S ã o Francisco basin, as specimens of the rio Paraná basin seem to possess a mostly red caudal fin, while specimens from the rio S ã o Francisco basin possess the caudal fin mostly yellow, with only the middle to distal portion red (see “Color in life”, above). Shibatta & Garavello (1993) made a morphometric comparison between populations of both basins using a principal component analysis, and were able to distinguish both populations, although with a considerable overlap ( Shibatta & Garavello, 1993, fig. 2). The overlap was interpreted by Shibatta & Garavello (1993: 113) as resulting from the similarity between some specimens from both basins. More recently, Machado et al. (2016) identified a 1.7% divergence in COI sequences within the species, one of the identified “molecular operational taxonomic unities” being confined to the rio S ã o Francisco basin, and the other occurring both at the upper rio Paraná and rio S ã o Francisco basin, and suggested that they represented putative distinct cryptic species. However, as noticed above, it is not possible to diagnose the Salminus hilarii populations from the rio S ã o Francisco and upper rio Paraná basin based on morphological characters (or else more than one species at the rio S ã o Francisco basin), and we suggest that the small genetic distance found between these populations is best considered as an evidence of a possible incipient case of speciation. We therefore conclude that the populations of S. hilarii from the rio Paraná and rio S ã o Francisco basins should be treated as a single species. The population from the rio Jaguaribe basin also did not differ in any morphometric or meristic features from the populations of the rio Paraná and rio S ã o Francisco basins.

Sexual dimorphism. As described in the Description, fin hooks are present at pelvic and anal fins of mature males (CAS 24782, 2, 192.0–210.0 mm SL; MZUSP 45271, 243 mm SL, MZUSP 20475, 2, 224–226 mm SL, MZUSP 86921, 243 mm SL, MZUSP 20471, 5, 216–264 mm SL, MZUSP 3044, 4, 165.6– 216 mm SL, and MZUSP 45272, 1, 211 mm SL). The specimens from the lots MZUSP 20471, MZUSP 45271, and MZUSP 20475 were dissected and were confirmed to be all males. Four dissected females presenting ripe ovaries with well-developed oocytes (MZUSP 19340, 246 mm SL; MZUSP 20475, 232 mm SL; MZUSP 45271, 2, 329–332 mm SL) does not possess any fin hooks. Godoy (1975: 369–370), based on the examination of several specimens from the rio Mogi Guaçu basin, reported that the presence of fin hooks in the anal fin is a condition unique to males, and that they disappear after the breeding season. Similarly to Salminus affinis (see under “Sexual dimorphism” of this later species), S. hilarii females grow larger than males. Godoy (1975: 371) reported that the largest female examined by him measured 42 cm TL and weighted 1 kg, whereas the larger male measured 32 cm TL and weighted 0.31 kg.

Common names. Brazil: “tabarana” (e.g., Magalh ã es, 1931; Godoy, 1975; Amaral Campos, 1944); “tubarana”, “tuburana”, “gitubarana”, “jutubarana” ( Fowler, 1941; Menezes, 1953; Paiva, 1959); “dourado-branco” ( Britski et al., 1984); “douradinho-voador” ( Alves & Pompeu, 2001); “traguira” (young specimens; Magalh ã es, 1931); Argentina: “dorado plateado” ( López et al., 2003).

Ecology, conservation. At the upper rio Paraná basin, Salminus hilarii occurs mainly in middle-sized rivers and large streams (e.g., Gomes & Azevedo, 1960; Godoy, 1975; Agostinho et al., 2003; Oliveira & Garavello, 2003; Birindelli & Garavello, 2005; Villares Junior & Goitein, 2015), rarely in floodplain lakes (e.g., Meschiatti et al., 2000; Esguícero & Arcifa, 2010), and typically favoring low-order waterbodies than S. brasiliensis , but occasionally both species can be found in syntopy. As all congeners, Salminus hilarii is considered to be ichthyophagous (e.g., Magalh ã es, 1931; Agostinho et al., 2003). Godoy (1975: 376) examined stomach contents of four specimens from the rio Mogi Guaçu (ranging from 8.2–20.5 cm TL), and reported exclusively small characins ( Astyanax spp. , Apareiodon affinis , and Parodon nasus ). Paiva (1959) examined stomach contents of 58 Salminus hilarii from the rio Salgado (rio Jaguaribe basin) and found mainly invertebrates (insects and shrimps) and a smaller proportion of fishes (small Characidae , Triportheus signatus , Pimelodella sp. , an unidentified Loricariidae , and, in a single stomach, another S. hilarii ), noticing that the frequency of fishes in the diet increased with the size of the specimens. Villares Junior & Goitein (2015) examined stomach contents of 198 specimens collected at the rio Sorocaba (Rio Paraná basin) and found exclusively fishes (mainly small characins) in its diet. Salminus hilarii was reported by Godoy (1975) as undertaking an upstream breeding migration during the rainy season. He specifically reported that three tagged specimens, marked between the months of October and November at the Cachoeira de Emas (rio Mogi Guaçu) were recaptured 51, 87, and 115 km upstream, after respectively, 12, 90, and 42 days ( Godoy, 1975: 374). According to Godoy (1975: 375), the spawning season of S. hilarii at the rio Mogi Guaçu occurs between December and January. Honji et al. (2009), based on the gonadosomatic index, considered that the breeding period of the species in the upper rio Tietê to happen between September and February, while Andrade et al. (2004) found specimens with mature gonads between October and January. The male specimens presenting fin hooks examined during the present study (CAS 24782, MZUSP 20471, MZUSP 20475, MZUSP 45271, MZUSP 45272, and MZUSP 86921), some of which confirmed to be ripe (see Sexual dimorphism, above) were captured during September, October, November, and March. Mature females with ripe gonads herein examined (MZUSP 20475, and MZUSP 45271) were collected in September and November. Salminus hilarii is a total spawner total ( Nakatani et al., 2001: 110). Ihering (1929: 75–76) reported a great spawning aggregation (called “piracema” in Brazil) of the species that happened circa 1914, at the rio Tamanduateí (a tributary of the rio Tietê, a locality currently within the urban area of the S ã o Paulo city), where a large number of specimens entered the floodplains, being intensely fished by the fishermen. During the subsequent days, larvae of S. hilarii were collected at the site ( Ihering, 1929). Godoy (1975: 375) reported a total fecundity ranging between 25,000 –30,000 oocytes in the species, while Ihering (1929: 81) reported a total fecundity of 38,000 –54,000 oocytes in specimens ranging between 310–360 mm TL, and the mean absolute fecundity of the species was calculated by Honji et al. (2009) to be 42,715 oocytes. The first maturation of females of the species was reported by Nakatani et al. (2001: 110) to happen around 230 mm TL, which is the size of the smallest mature female herein examined (MZUSP 20475, 232 mm TL). The smallest male herein examined presenting fin hooks and as such presumably mature is 165.6 mm SL (MZUSP 3044). Based on the examination of 382 specimens collected at the Três Marias dam (rio S ã o Francisco), Andrade et al. (2004) reported that the smallest male and female presenting mature gonads measured 195.0 and 207.0 mm SL, respectively. Based on specimens reared in captivity, Silva et al. (2015: 552) reported that S. hilarii reaches sexual maturity at the age of two years. The ontogenetic development of the species was described and illustrated by Nakatani et al. (2001: 110–114). Floodplain lakes were reported to be used by juveniles of the species ( Esguícero & Arcifa, 2010).

Salminus hilarii is a highly sought species by anglers, but it was never considered important in commercial fisheries due its relatively small size and low natural abundance (Schubart, 1949: 151; Monteiro, 1953; Godoy, 1975: 376), with the exception in the rio Jaguaribe basin, where the species was considered very important in the fisheries ( Menezes, 1953). The species has declined across most of its range due to environmental degradation such as water pollution and damming, but it is relatively resilient to anthropogenic impacts as seemingly viable populations are still present in areas with a long history of disturbances as the lotic stretches of some old reservoirs (e.g., Furnas reservoir, rio Grande basin; Jurumirim reservoir, rio Paranapanema; Três Marias reservoir, rio S ã o Francisco; e.g., Carvalho et al., 1998, Andrade et al., 2004) and in relatively short, isolated river stretches due to downstream water pollution (e.g., the upper rio Tietê above S ã o Paulo city). The fragmentation of the populations of S. hilarii due to damming and the pollution of river stretches acting as a barrier as the rio Tietê in the S ã o Paulo city was evidenced by Silva et al. (2015), who detected genetic differentiation among populations of the species in the rio Grande basin separated by several dams lacking any fish passage systems, and a low genetic diversity in the population from the upper rio Tietê. Esguícero & Arcifa (2010) also documented a morphometric differentiation between two populations of the species separated by an old hydroelectric dam that lack an efficient fish passage system at the rio Jacaré-Guaçu, a tributary of the rio Tietê. Although these studies show that there is evidence that populations of S. hilarii are undergoing some impacts due to the fragmentation of the habitat, our overall conservation assessment on the species is that it cannot be considered as threatened as it is still widespread and moderately common across much of its range. However, the population of S. hilarii occurring in the rio Jaguaribe basin in northeastern Brazil, where the species was considered to be abundant in the past (3,789 specimens fished between 1943 and 1947 in two reservoirs; Menezes, 1953: 358) is heavily impacted by damming, water abstraction, and sewage pollution, and should be considered as threatened with extinction (A.K. Zeinad and T.P.A. Ramos, pers. comm.).

Remarks. Salminus hilarii was supposed in the past to present a broad distribution across rivers basins of northern cisandean South America, i.e., the Orinoco, western Amazon, and rio Tocantins basins (e.g., Saul, 1975; Stewart et al., 1981; Santos et al., 1984; Géry & Lauzanne, 1990; Taphorn, 1992). We herein restrict the occurrence of S. hilarii to the upper rio Paraná, rio S ã o Francisco, and rio Jaguaribe basins in northeastern and southeastern Brazil, and adjacent areas in Paraguay and Argentina, as the populations from northern cisandean South America actually belong to S. iquitensis and S. santosi . Machado et al. (2016) had previously noticed that samples assigned to S. hilarii from the western Amazon and rio Tocantins basins had a 9.4–10.8% divergence in COI sequences from samples from the rio S ã o Francisco and upper rio Paraná basins.

Salminus hilarii was described by Valenciennes (in Cuvier & Valenciennes, 1850: 64–65) diagnosing it from Salminus cuvieri (= S. brasiliensis ). Most characters listed by Valenciennes (in Cuvier & Valenciennes, 1850) as the degree of sculpturing of the infraorbital bones, the shape of the first infraorbital, the degree of bifurcation of the caudal fin, and the size of the anal fin, are not truly diagnostic between both species. However, Valenciennes (in Cuvier & Valenciennes, 1850) noticed that the scales in S. hilarii are considerably larger and consequently scales counts in the species are much lower than in S. brasiliensis , which is indeed one of the diagnostic characters between both species. Valenciennes (in Cuvier & Valenciennes, 1850) examined specimens from the rio S ã o Francisco basin, collected by Auguste de Saint-Hilaire, and some from “l’intérieur du Brésil ”, collected by Castelnau. The specimens identified as S. hilarii collected by Castelnau actually belong to S. santosi (see the item “Remarks” of this species). Géry & Lauzanne (1990: 117) designated one of the specimens collected by Saint-Hilaire (MNHN A.8658) as the lectotype of Salminus hilarii , mentioning however that this designation had already being made by “Géry, 1980”. As this purported previous designation apparently refers rather to the date when Géry examined the type specimens and not a specific publication, the lectotype designation should be assigned to Géry & Lauzanne (1990).

Due to the overlap in scale counts presented by Salminus hilarii with the sympatric S. franciscanus , there was some confusion regarding the identity of both species in the early literature (i.e., Ļtken, 1875a, 2001; Steindachner, 1880; see Lima & Britski, 2007). It was only after Eigenmann (1916) that both species were definitely considered as distinct, even though the sole character used to distinguish S. hilarii and S. franciscanus (scale counts) actually overlaps between them. In spite of that, both species were considered as clearly distinct by Brazilian authors (e.g., Moraes & Schubart, 1955: 11; Britski et al., 1984: 51–52), due to the differences in maximum size, color pattern in life, and biology.

Kner (1860: 51–52) cited specimens of Salminus cuvieri from “Irisanga” (= Orissanga, currently Estiva Gerbi, rio Mogi-Guaçu basin, S ã o Paulo) and “Rio Cujaba” (rio Cuiabá, Mato Grosso). Kner (1860) clearly mixed specimens of S. hilarii and S. brasiliensis in his account, the specimen from Orissanga clearly referring to the earlier species as the common name recorded for the species by the collector, J. Natterer, was “tabarana”, while the specimen from Cuiabá undoubtedly should refer to S. brasiliensis , as the only species of the genus occurring in the rio Paraguai basin. An unavailable manuscript name by Natterer, Salmo melanurus , cited by Kner (1860: 52), is herein considered as a synonym of S. hilarii .

Fowler (1941: 191–192) described Brycon erythrura from the rio Jaguaribe, Ceará state, Brazil, and only compared it very succinctly with a single presumable congener, B. orbygnianus . The drawing of the holotype of B. erythrura ( Fowler, 1941: fig. 101) shows a fish much more similar to a Salminus , with a long and narrow maxillary bone and a well-developed third infraorbital (although its boundary with the fourth infraorbital bone was not depicted). Salminus hilarii was cited from the rio Jaguaribe basin by Menezes (1953) and Paiva (1959), the first suggesting that Brycon erythrura was a junior synonym of the species. However, subsequent authors mentioning this nominal species were apparently unaware of this suggestion, as Myers & Weitzman (1966) only pointed that Brycon erythrura probably belonged to the genus Salminus , and Géry & Lauzanne (1990: 116) indicating it to be likely a synonym of S. hilarii , without citing Menezes (1953) as corroborating this view. The examination of the holotype (ANSP 69608) and the remaining type-series of B. erythrura , as well as additional material from the rio Jaguaribe basin, confirmed it to be a synonym of S. hilarii . See the item “Geographic variation” for more comments concerning the population of S. hilarii from the rio Jaguaribe basin.

As noticed in the “Diagnosis”, Salminus hilarii possess the lower scale counts among all Salminus species, however, with a large overlap with its congeners, except for S. brasiliensis . Valenciennes (in Cuvier & Valenciennes, 1850), Eigenmann (1916), and Géry & Lauzanne (1990) pointed that S. hilarii possess a lower number of branched anal fin rays when compared with other Salminus species. However, anal fin branched rays counts of S. hilarii when compared with congeners largely overlap due to the great range of variation within the species (19–27, modally 22 in S. hilarii , vs. 21–27, modally 23, in S. affinis , 20–25, modally 23, in S. brasiliensis , 23–28, modally 25, in S. franciscanus , 20–25, modally 23, in S. iquitensis , and 18–24, modally 22, in S. santosi ).

Distribution. Salminus hilarii is widely distributed across the upper rio Paraná basin in Brazil, extending into adjacent Paraguay (río Monday and río Acaray) and Argentina (rio Iguaçu, below the falls; Vittar et al., 2002; López et al., 2003). It also occurs at the upper and middle rio S ã o Francisco, and in the isolated rio Jaguaribe basin, in northeastern Brazil ( Fig. 11 ). The species is nearly confined in the rio Paraná basin to its upper portion, above the drowned Sete Quedas/Guayrá falls, an area known for the high endemism of its ichthyofauna ( Langeani et al., 2007). However, the records of the species from Paraguay (río Acaray and río Monday) and one record from Brazil (MZUSP 21080) were done below the Sete Quedas/Guairá falls, before the closure of the Itaipu dam (see Discussion, below). Silva et al. (2020: 5) recorded the species for the rio S ã o Francisco basin in Bahia state, northeastern Brazil, based on two lots (UNT 12431, UNT 12457). These records are from the mainstream of the rio S ã o Francisco at Bom Jesus da Lapa. The northernmost record for S. hilarii in the rio S ã o Francisco basin in the present study is a specimen collected at the rio Verde Grande, Minas Gerais state (MZUSP 45280), near the border with Bahia state. Although the occurrence of S. hilarii in Bahia state is plausible, this species is always collected in tributaries and never in the mainstream of large rivers. All Salminus specimens examined by the author from Bahia state are S. franciscanus (see Lima & Britski, 2007). Since small specimens of S. franciscanus can be easily confused with S. hilarii (see Diagnosis and Remarks, above), we suggest that these records probably refer instead to S. franciscanus and thus, the occurrence of S. hilarii in Bahia state should be considered doubtful.

Material examined. Type material. MNHN A.8658 (1, 165.9 mm SL), “ Rio San Francisco , A. Saint-Hilaire ”; lectotype of Salminus hilarii Valenciennes ; MNHN A.8557 (1, 144.1 mm SL), same data; paralectotype of S. hilarii Valenciennes. ANSP 69608 (1, 182.0 mm SL), Brazil, Ceará, rio Jaguaribe, Orós. c. 6º14′S, 38º55′W; R. von Ihering, 1937; holotype of Brycon erythrura Fowler. ANSP 60609–11 (3, 143.8–163.0 mm SL) ; ANSP 69612–3 (2, 136.9–145.0 mm SL), same data; paratypes of Brycon erythrura Fowler. ANSP 69614–7 (4, 81.4–137.5 mm SL), Brazil, Ceará, rio Jaguaribe, Russas , c. 4º58′S, 37º53′W; R. von Ihering, 1937; paratypes of Brycon erythrura Fowler .

Not types. Brazil. Rio Jaguaribe basin, Ceará: UMMZ 147356 (3, 125.0– 224.1 mm SL), rio Salgado, Icó , c. 6º24′S, 38º52′W; R.S. Menezes, 1945 (?). USNM 143845 (1, 114.7 mm SL), rio Salgado, Icó , c. 6º24′S, 38º52′W; R.S. Menezes, Aug–Sept 1947. Rio São Francisco basin, Minas Gerais: LIRP 641 (1, 235.0 mm SL), S„o Roque de Minas, rio São Francisco , Fazenda Casca D′Anta , 20º19′S, 46º31′W; A.C. Lopes, 12 Dec 1993. LBP 11295 (5, 241.0–304.0 mm SL); ZUEC 17434 (1, 277.0 mm SL), São Roque de Minas, rio São Francisco , 20º20′53′′S, 46º4′11′′W; M. Mehanna & L. Milano, 14 Apr 2010. MCP 34641 (1, 231.6 mm SL), Iguatama, ribeirão São Miguel, trib. rio São Francisco , 20°12′S, 45°39′9′′W; B.P. Nogueira et al., 27 Sept 2003. MNRJ 24199 (4, 113.2– 116.4 mm SL), Lagoa Santa, córrego do Quebra , trib. rio das Velhas, c. 19º39′S, 43º51′W; N. Santos, J. Machado & H. Berla, Nov 1947. LBP 254 (1, 189.0 mm SL), Três Marias, rio São Francisco , c. 18º22′S, 45º17′W; C. Oliveira et al., 28 Oct 1996. MZUSP 19927 (1, 158.6 mm SL), rio São Francisco, Três Marias dam, c. 18º22′S, 45º17′W; CODEVASF, 1978. MZUSP 45257 (5, 135.1–181.0 mm SL); MZUSP 45258 (4, 142.0– 199.4 mm SL), rio S„o Francisco, Três Marias dam, c. 18º22′S, 45º17′W; A. Copriva, 10–12 Aug 1982. MZUSP 45259 (2, 212.0-255.0 mm SL); MZUSP 45260 (4, 206.0–251.0 mm SL), rio São Francisco, Três Marias dam, c. 18º22′S, 45º17′W; A. Copriva, 21 March–4 May 1983. MZUSP 45256 (6, 153.7– 171.9 mm SL), Morada Nova de Minas, rio S„o Francisco, Três Marias dam, c. 18º22′S, 45º17′W; Y. Sato, 4–5 Oct 1982. MCP 14055 (2, 232.1– 232.7 mm SL), rio São Francisco, Três Marias dam, c. 18º22′S, 45º17′W; Y. Sato, June 1989. MCP 14122 (5, 121.4– 217.4 mm SL), rio São Francisco , between Três Marias and Pirapora; Y. Sato, Nov 1987. MZUSP 73749 (1, 106.3 mm SL), Corinto, rio Bicudo, fazenda Bom Jardim , 18°21′31′′S, 44°35′30′′W; C.B.M. Alves & P.S. Pompeu, 14 Aug 2001. MZUSP 73834 (1, 255.0 mm SL), Curvelo, rio das Velhas, fazenda Xavante , 18°53′22′′S, 44°8′15′′W; C.B.M. Alves & P.S. Pompeu, 14 Dec 1999. MZUSP 47311 (3, 108.1– 145.8 mm SL); USNM 345759 (2, 110.6- 122.8 mm SL), tributary of rio Jequitaí , at road BR-135, between Buenópolis and Engenheiro Dolabela, c. 17º30′S, 44º3′W; Exp. MZUSP / USNM /UFSCAR, 20 July 1994. LIRP 4670 (2, 165.0–170.0 mm SL), Jequitaí, rio Jequitaí (15 km downstream Jequitaí), 17º14′30′′S, 44º25′W; F.A. Bockmann, 15 Nov 1995. LBP 28317 (1, 79.0 mm SL), Guarda Mor, trib. rio Escuro ( rio Paracatu basin), 17º44′53′′S, 47º5′40′′W; B.F. Melo, G.S.C. Silva, R. Devidé & L.H. Silva, 15 Jan 2019. MZUSP 47467 (1, 141.1 mm SL), Montes Claros, rio Verde , between Francisco Sá and Montes Claros, 16º39′0′S, 43º42′5′′W; Exp. MZUSP/USNM/UFSCAR, 23 July 1994. MCP 16711 (2, 197.3–213.0 mm SL), Montes Claros, rio Verde Grande, road Montes Claros / Janaúba , 16°39′1′′S, 43°42′49′′W; R.E. Reis, J.P. Silva, E.L. Pereira & S.A. Schaefer, 20 Jul 1993. ANSP 171720 (2, 170.6- 175.7 mm SL), Francisco Sá, rio Catitu, 32 km N of Montes Claros, road to Janaúba , 16º31′18′′S, 43º40′49′′W; S.A. Schaefer, W.G. Saul, R.E. Reis, et al., 20 Jul 1993. MCP 18055 (3, 221.4– 232.3 mm SL); MNRJ 18055 (3, 230.0– 232.3 mm SL), Palmital, rio Preto (trib. rio Paracatu ), near ASCEB, c. 16°12′S, 47°20′W; C. A. Figueiredo & D.F. Moraes Jr., 15 Dec 1998. MNRJ 18132 (3, 229.4– 239.5 mm SL); MNRJ 18153 (2, 193.0– 231.9 mm SL); MNRJ 18262 (1, 274.5 mm SL); MNRJ 18263 (1, 253.5 mm SL), Palmital, rio Preto (trib. rio Paracatu ), near ASCEB, c. 16°12′S, 47°20′W; C. A. Figueiredo & F. A. Bockmann, 7 Nov 1998. MNRJ 17613 (2, 224.1– 246.3 mm SL); MNRJ 18134 (3, 221.7– 240.9 mm SL); MNRJ 18155 (1, 267.0 mm SL), Palmital, rio Bezerra (mouth of lagoa Perta-Pé), trib. rio Preto (trib. rio Paracatú ), 15º59′4′′S, 47º11′52′′W; F.A. Bockmann & C. A. Figueiredo, 10 Nov 1998. MNRJ 18116 (1, 167.8 mm SL), Palmital, rio Bezerra (mouth of lagoa Perta-Pé), trib. rio Preto (trib. rio Paracatú ), 15º59′4′′S, 47º11′52′′W; C.A. Figueiredo & D.F. Moraes Jr., 19 Dec 1998. MNRJ 18156 (1, 261.8 mm SL); MNRJ 18159 (1, 211.2 mm SL), Palmital, rio Preto, trib. rio Paracatu , below cachoeira do Repuxo , fazenda Mata Velha ; F.A. Bockmann & C. A. Figueiredo, 9 Nov 1998. MNRJ 18135 (1, 263.4 mm SL), Palmital, rio Preto (trib. rio Paracatu ), above Cachoeira de Queimados , c. 16°12′S, 47°20′W; F.A. Bockmann & C. A. Figueiredo, 11 Nov 1998. MZUSP 45280 (2, 125.6– 129.2 mm SL), Manga, rio Verde Grande , trib. rio S„o Francisco, 5 km from Gado Bravo, c. 14º56′S, 43º30′W; G. B. Santos, 7 Sept 1986. NMW 5686 (2, 130.0–133.0 mm SL), “Rio San Francisco & Rio das Velhas” [no precise locality]; no collector or date specified. Distrito Federal: MNRJ 18118 (1, 65.5 mm SL), rio Preto (near mouth of rio Bezerra), trib. rio Paracatu , near to road to Brasília , c. 16º2′S, 47º19′W; C.A. Figueiredo & D.F. Moraes Jr., 19 Dec 1998. Rio Paraná basin, Goiás: CAS 24782 (2, 192.0–210.0 mm SL), Planaltina , c. 15º38′S, 47º40′W; C. Ternetz, 11 Sept 1923. MZUSP 47772 (1, 102.1 mm SL), Goiânia, rio Meia Ponte , c. 16º35′S, 49º19′W; D.F. Pereira, no date. MCP 34580 (1, 284.7 mm SL), Terezópolis de Goiás, ribeirão João Leite (trib. rio Meia Ponte ), 16°31′29′′S, 49°08′31′′W; F.L. T. Garro, 11 Oct 2003. MNRJ 17613 (2, 142.9– 156.2 mm SL), rio São Francisco (trib. rio Paranaíba ), c. 16º26′, 50º21′W; D. Sagim Jr., 4 May 1997. MZUSP 73367 (1, 314.0 mm SL), Itumirim, rio Corrente, trib. rio Paranaíba , c. 18º31′S, 52º6′W; J.C. Garavello & M.L. Mussara, 28 Nov–1 Dec 1994. ZUEC 7020 (1, 113.0 mm SL), Rio Verde, córrego das Pedras, fazenda Lagoa das Pedras ; B.F. Amaral & O.C. Oliveira, 26 Jan 1974. LIRP 3436 (1, 285.0 mm SL), Catal „o, rio S„o Bento, fazenda Vitória , Chapadão da Anta Gorda , 17º46′54′′S, 47º31′58′′W; E.S. R. Sá, 26 Apr 2002. LIRP 3561 (2, 246.3– 261.8 mm SL): Catalão, rio São Bento, fazenda Vitória , Chapadão da Anta Gorda , 17º46′54′′S, 47º31′58′′W; no collector specified, 26–27 Jul 2002. MNRJ 19773 (1, 117.1 mm SL), Catal „o, rio S„o Marcos, trib. rio Paranaíba , fazenda Dorvinas , 18°4′5′′S, 47°40′26′′W; C.A. Figueiredo, F.A. Bockmann & A.P. R. Pires, 23 Sept 1999. MNRJ 19725 (1, 17.0 mm SL), Davinópolis, rio São Bento, afl. rio São Marcos , 18º8′1′′S, 47º38′23′′W; C.A. Figueiredo, F.A. Bockmann & A.P. R. Pires, 27 Sept 1999. MCP 28311 (1, 185.4 mm SL), Davinópolis, rio São Bento , 18°6′58′′S, 47°37′13′′W; C. Lucena, J. Silva, E. Pereira & A. Cardoso, 22 Jan 2001. MZUSP 84497 (3, 119.6– 345 mm SL), Campo Alegre, rio Corrente (trib. rio Paranaíba ), 18°39′17′′S, 51°53′06′′W; G. R. Aloísio, 29 May 2003. Minas Gerais: MNRJ 18165 (1, 257.3 mm SL); MNRJ 18173 (1, 217.7 mm SL), Palmital, rio S„o Marcos, trib. rio Paranaíba, c. 16°07′S, 47°19′W; F.A. Bockmann & C.A. Figueiredo, 11–12 Nov 1998. LIRP 6549 (1, 315.0 mm SL), Perdizes, rio Araguari, UHE Nova Ponte (reservoir), 19º18′2′′S, 46º50′34′′W; F. Apone et al., 11 Sept 2008. MZUSP 38874 (9, 168.5–291.0 mm SL), rio Paranaíba, UHE Bocaina, c. 18º29′S, 47º56′W; Leme Engenharia S/A, Nov 1987 – June 1988. ZUEC 6784 (1, 253 mm SL), Uberlândia, rio Tejuco (trib. rio Paranaíba), c. 19º20′S, 48º24′W; A. Giaretta, 17 Jul 1999. LBP 29521 (1, 276.0 mm SL), Boa Esperança, ribeir„o Marimbondinho, Furnas Reservoir , 21º4′18′′S, 45º33′44′′W; A. Nobile, 30 May 2019. MNRJ 17079 (1, 146.1 mm SL), Ibituruna, rio das Mortes, trib. rio Grande, near Ibituruna , c. 21°08′S, 44°43′W; P.M.C. Araújo, F.A. Bockmann & F. Regalo, 14 Feb 1998. MZUSP 20471 (6, 211.0–264.0 mm SL), rio Grande, represa dos Camargos , c. 21º17′S, 44º37′W; CETESB, 2–3 Oct 1975. MZUSP 20468 (2, 287.0–296.0 mm SL), Alfenas, rio Grande, Furnas reservoir, c. 21°26′S, 45°57′W; CETESB, 2–3 Oct 1975. LBP 320 (1, 174.0 mm SL): Alfenas, Furnas reservoir, rio Grande , c. 21°26′S, 45°57′W; S.F. Andrade & S. Marques, 20 Oct 1996. FMNH 57590 (1, 128.4 mm SL): Bom Jardim de Minas, rio Grande , above fall, c. 21º57′S, 44º11′W; J.D. Haseman, 7 July 1908. LIRP 7205 (1, 215.0 mm SL), Jacutinga, rio Mogi Mirim (trib. rio Mogi Guaçu ), PCH Jacutinga , 22º15′29′′S, 46º40′34′′W; F. Apone et al., 1 June 2009. MZUSP 45271 (3, 243.0– 332.0 mm SL), rio Grande, at border between Minas Gerais and S„o Paulo states (no precise locality); CETESB, Sept 1980. Mato Grosso do Sul: MZUSP 20263 (2, 149.2– 153.9 mm SL), rio Paraná, Ilha Solteira (cofferdam, left margin), c. 20º26′S, 51º24′W; Exc. MZUSP, 25–28 May 1972. NUP 3723 (2 of 5, 206.0–209.0 mm SL), Taquaruçu, rio Ivinheima, c. 22º28′S, 53º19′W; Nupélia, March 2005. São Paulo: MZUSP 47936 (1, 214.0 mm SL), Palestina, rio Turvo, bairro Formiga (presently Boturuna), c. 20º14′S, 49º29′W; V. Garutti, 27 July 1977. MZUSP 1970 (1, 168.4 mm SL), rio Feio (= rio Aguapeí); F. Ģnther, 1905. MZUSP 20475 (3, 224.0–232.0 mm SL), Volta Grande reservoir, rio Grande, c. 20º7′S, 48º0′W; CETESB, 6–7 Nov 1975. MZUSP 2056 (1, 204.0 mm SL), Franca, c. 20º30′S, 47º20′W; E. Garbe, 1910. LIRP 104 (1, 263.0 mm SL), Cajuru, ribeirão da Boiada (trib. rio Pardo), 21º25′S, 47º13′W; Exc. Setor de Zoologia, 15 Nov 1985. MZUSP 19516 (1, 159.7 mm SL), rio Pardo, Limoeiro dam, c. 21º37′S, 47º0′W; Dep. Prod. Animal, 29 Feb 1964. MZUSP 19650 (2, 112.9– 116.5 mm SL), rio Pardo, Limoeiro dam, c. 21º37′S, 47º0′W; H. Britski, 13 Apr 1964. MZUSP 19515 (1, 285.0 mm SL), rio Pardo, Limoeiro dam, c. 21º37′S, 47º0′W; C.M. Machado, 29 Feb 1964. MCP 14436 (1, 192.2 mm SL); USNM 302489 (3, 191.0–204.0 mm SL), Santa Rosa do Viterbo, rio Pardo, below fish ladder of Itaipava, 21°25′S, 47°20′W; R. M.C. Castro, 25 Oct–14 Nov 1984. MZUSP 53461 (1, 220.4 mm SL), S„o José do Rio Pardo, rio do Peixe , below UHE Rio do Peixe , c. 21º36′S, 46º48′W; P. Gerhard, 18 Sept 1997. LIRP 364 (1, 122.0 mm SL), Luís Antônio, Lagoa do Diogo, rio Mogi Guaçú , 21º37′26′′S, 47º48′22′W; R. M.C. Castro et al., 22 Oct 1999. MZUSP 45276 (2, 134.3– 152.7 mm SL), Luís Antônio, Lagoa Nova, trib. rio Mogi-Guaçú , c. 21º36′S, 47º50′W; A. Copriva, 27 May 1981. CAS 79294 (1, 248.0 mm SL); CAS 79295 (1, 278.0 mm SL), Pirassununga, Rio Mogi Guaçu, Cachoeira de Emas , c. 21º55′S, 47º22′W; M.P. Godoy, 23 March 1970. LBP 82 (5, 155.0–242.0 mm SL), Pirassununga, rio Mogi-Guaçú, Cachoeira de Emas , 21º55′37′′S, 47º22′4′′W; C. Oliveira, R. Devidé & M.L. Carvalho, 4 Aug 1995. LIRP 14493 (9, 123.1– 230.7 mm SL); Pirassununga, rio Mogi-Guaçú, Cachoeira de Emas , c. 21º55′S, 47º22′W; O. Schubart, 19 Apr 1943. MZUSP 1528 (3, 196.5–293.0 mm SL), Pirassununga, rio Mogi-Guaçú, Cachoeira de Emas , c. 21º55′S, 47º22′W; no collector specified, 1908. MZUSP 19340 (1, 246.0 mm SL), Pirassununga, rio Mogi-Guaçu, Cachoeira de Emas , c. 21º55′S, 47º22′W; E. Dente, 1947. MZUSP 19390 (1, 104.9 mm SL), Pirassununga, rio Mogi-Guaçu, Cachoeira de Emas , c. 21º55′S, 47º22′W; Exc. Departamento de Zoologia, 29 June–1 Aug 1962. MZUSP 19461 (2, 123.1–134.0 mm SL), Pirassununga, rio Mogi-Guaçu , Cachoeira de Emas , c. 21º55′S, 47º22′W; Exc. Departamento de Zoologia , 1 May 1963. MZUSP 19462 (3, 75.2–130.0 mm SL); MZUSP 19469 (2, 98.8–174.1 mm SL), Pirassununga, rio Mogi-Guaçu, Cachoeira de Emas , c. 21º55′S, 47º22′W; Exc. Departamento de Zoologia , 1–6 May 1963. MZUSP 19479 (1, 107.2 mm SL); MZUSP 19480 (3, 95.2–116.0 mm SL), Pirassununga, rio Mogi-Guaçu, Cachoeira de Emas , c. 21º55′S, 47º22′W; Exc. Departamento de Zoologia, 24 July 1963. MZUSP 19482 (2, 126.6– 190.3 mm SL), Pirassununga, rio Mogi-Guaçu , Cachoeira de Emas , c. 21º55′S, 47º22′W; Exc. Departamento de Zoologia, 25 Aug 1963. MZUSP 19488 (1, 88.9 mm SL), Pirassununga, rio Mogi-Guaçu , Cachoeira de Emas , c. 21º55′S, 47º22′W; P.E. Vanzolini & H. Britski, 20–21 Aug 1963. MZUSP 19497 (1, 177.9 mm SL), Pirassununga, rio Mogi-Guaçu, Cachoeira de Emas , c. 21º55′S, 47º22′W; H. Britski, 22 Oct 1963. MZUSP 45263 (7, 195.6–248.0 mm SL), Pirassununga, Rio Mogi Guaçu, Cachoeira de Emas , c. 21º55′S, 47º22′W; A. Copriva, 10 July 1984. MZUSP 45267 (1, 131.6 mm SL), Pirassununga, rio Mogi Guaçú, Cachoeira de Emas , c. 21º55′S, 47º22′W; A. Copriva, 2 Sept 1973. MZUSP 45264 (2, 239.0–263.0 mm SL), Pirassununga, rio Mogi-Guaçú, Cachoeira de Emas , c. 21º55′S, 47º22′W; A. Copriva, 31 Oct 1983. MZUSP 80934 (3, 123.9– 144.4 mm SL), Pirassununga, rio Mogi-Guaçu, Cachoeira de Emas , c. 21º55′S, 47º22′W; P.E. Vanzolini & R. Rebouças, Sept 1962. MZUSP 19476 (1, 99.0 mm SL); MZUSP 19648 (1,107.6 mm SL), Pirassununga, rio Jaguari-Mirim , at its mouth, 21º58′53′′S, 47º17′37′′W; R. Kloss, 19 Feb 1965. CAS 152634 (1, 198.0 mm SL), Pirassununga, rio Mogi Guassu ; O. Schubart, 1943. MZUSP 2067 (1, 269.0 mm SL), Pirassununga ; no collector specified, 1907. MZUSP 35740 (4, 107.7– 130.2 mm SL), rio Mogi-Guaçu, Cachoeirinha ; Exc. DZ, 17 Feb 1963. MZUSP 45266 (3, 141.1– 158.9 mm SL), rio Mogi-Guaçú [no specific locality]; A. Copriva, 31 March–29 April 1982. MZUSP 45261 (2, 143.0– 194.4 mm SL), rio Mogi Guaçú [no specific locality]; A. Copriva, 26 Feb–22 May 1981. MZUSP 45262 (2, 198.9–241.0 mm SL), rio Mogi-Guaçú [no specific locality]; A. Copriva, 26 Feb–8 Oct 1980. MZUSP 45265 (1, 226.0 mm SL), rio Mogi Guaçú [no specific locality]; A. Copriva, 10 Jul 1984. MZUSP 45272 (4, 211.0–262.0 mm SL), rio Mogi-Guaçú [no specific locality]; A. Copriva, 19 Sept–5 Dec 1983. MZUSP 40113 (8, 2 c&s, 81.9–175.7 mm SL), Pereira Barreto, rio Tietê , c. 20º41′S, 51º7′W; T. Nakaya, 14 April 1989. MZUSP 3044 (12, 160.0–218.0 mm SL), Macaubal, ribeirão Ponte Nova , c. 20º49′S 50º0′W; J. Lima, 1941. FMNH 57595 (1, 141.3 mm SL), Salto Avanhandava, rio Tietê , c. 21º13′S, 49º57′W; J.D. Haseman, 15 Sept 1908. ZUEC 3661 (1, 255.0 mm SL): Buritama, rio Tietê, near UHE Nova Avanhandava , c. 21º7′S, 50º13′W; S.P.B. Sazima & I. Sazima, 14 May 1998. MZUSP 19962 (2, 110.5– 141.1 mm SL), Penápolis, rio Tietê , c. 21º16′S, 49º51′W; F. Casasco, 20 Oct 1972. MZUSP 83372 (1, 199.4 mm SL), Bariri, rio Tietê, below UHE Bariri dam, 22°8′50′′S, 48°45′06′′W; A. Akama, 3–7 Nov 2003. ZUEC 11008 (1, 168.6 mm SL): Jaú, fazenda Salto São Pedro, Pouso Alegre , 22º12′56′′S, 48º37′12′′W; J.L. Hübner Jr., 23 Oct 2013. LIRP 10177 (8, 151.1–275.0 mm SL), Gavião Peixoto, rio Boa Esperança (trib. rio Jacaré Guaçu ), 21º52′16′′S, 48º31′2′′W; A. Esguícero, 17 Apr 2013. MZUSP 45278 (1, 165.8 mm SL), Araraquara, rio Jacaré Guaçu, “Saltinho da Ilha”, fazenda Alabama , c. 21º52′S, 48º16′W; J. R. Moreira, 18 Oct 1984. MZUSP 45277 (2, 208.0–252.0 mm SL), São Carlos, rio JacaréGuaçú, Usina Santana , c. 22º4′S, 48º3′W; A. Copriva, June 1982. MZUSP 45279 (1, 114.4 mm SL), Araraquara, rio Jacaré Guaçú, UHE Gavião Peixoto , 21º51′S, 48º29′22′′W; J.C. Garavello, 26 Nov 1982. MZUSP 45275 (3, 226.0– 297.0 mm SL), rio Jacaré-Guaçú [no specific locality]; A. Copriva, 2 June–24 Sept 1982. MZUSP 19510 (4, 157.2– 266.0 mm SL), rio Tietê, Barra Bonita , c. 22º31′S, 48º32′W; Dep. Prod.Animal, 30 Aug 1963. CAS 11749 (1, 151.9 mm SL), Piracicaba , c. 22º43′S, 47º39′W; no collector specified, Nov 1906. FMNH 57591 (1, 280.0 mm SL): Piracicaba , c. 22º43′S, 47º39′W; J.D. Haseman, 23 July 1908. MZUSP 20264 (1, 170.4 mm SL), Corumbataí, rio Corumbataí , c. 22º14′S, 47º37′W; H. Britski, 14 Jan 1972. MZUSP 19492 (1, 247.0 mm SL), Corumbataí, rio Corumbataí , c. 22º14′S, 47º37′W; V. M. Britski, 12 Oct 1963. MZUSP 83691 (2, 121.3– 151.9 mm SL), Corumbataí, rio Corumbataí , 22°12′S, 47°37′W; S.E. Lima & I.B. Cardone, June 2000. MZUSP 19673 (2, 125.7– 127.8 mm SL), Americana , represa de Americana, c. 22º43′S, 47º16′W; Depto. Prod. Animal, 23 July 1965. ZUEC 4874 (1, 141.0 mm SL); ZUEC 5418 (1, 171.2 mm SL), Sumaré, ribeirão Quilombo (trib. rio Atibaia ), c. 22º48′S, 47º17′W; J. Vas- concellos-Filho, Oct–Nov 1977. CAS 24797 (2, 265.0–300.0 mm SL); MZUSP 1536 (4, 226.0–245.0 mm SL), Itatiba , c. 22º58′S, 46º50′W; J. Lima, 1907. MZUSP 2087 (2, 256.0-273.0 mm SL), Itatiba , c. 22º58′S, 46º50′W; J. Lima, Nov 1907. MZUSP 3362 (1, 271.0 mm SL), Monte Alegre do Sul, ribeirão do Chico , c. 22º42′S, 46º43′W; J. Lima, no date. LBP 19722 (1, 225.0 mm SL), Salto, rio Piraí (trib. rio Jundiaí ), 23º11′6′′S, 47º14′19′′W; D.F. Souza, R. Devidé & A. Nobile, 21 Mar 2015. CAS 77543 (1, 161.3 mm SL), S ã o Paulo, rio Tietê; H. von Ihering, 1901– 1905. MZUSP 1546 (4, 158.5–191.0 mm SL), S ã o Paulo, rio Tietê (purchased); no collector specified, Aug 1905. MZUSP 2035 (1, 161.1 mm SL), S ã o Paulo, rio Tietê ; no collector specified, June 1894. LIRP 12665 (1, 320.0 mm SL), Embu-Guaçu, rio Embu-Guaçú (trib. rio Tietê ), 23º49′2′′S, 46º48′39′′W; A. Oliveira, 13 Jan 2016. CAS 24781 (1, 198.0 mm SL), São Paulo, Ipiranga , c. 23º35′S, 46º36′W; H. von Ihering, 1901-1905. MZUSP 2038 (1, 181.7 mm SL), São Paulo, Ipiranga , c. 23º35′S, 46º36′W; J. Lima, Jan 1905. MZUSP 2001 (1, 220.0 mm SL), São Paulo, rio Tamanduateí, Ipiranga , c. 23º35′S, 46º36′W; J. Lima, Sept 1904. MZUSP 1791 (1, 122.6 mm SL), São Paulo, Ipiranga, rio Tamanduateí , c. 23º35′S, 46º36′W; J. Lima, 1909. MZUSP 1656 (6, 108.7– 124.3 mm SL), São Paulo (purchased at the market); no collector or date specified.; MZUSP 86921 (3, 243.0–329.0 mm SL), Biritiba-Mirim, rio Tietê , 23°34′05′′S, 46°00′38′′W; O. T. Oyakawa, J.L. Birindelli & J.C. Nolasco, 21 March 2005. FMNH 57592 (2, 119.2– 120.8 mm SL), “Sapina” [not located], rio Tietê ; J.D. Haseman, 23 July 1908. MZUSP 3049 (1, 145.0 mm SL), rio Tietê [no specific locality]; A. Marques, 1941. MZUSP 45273 (4, 185.9–223.0 mm SL), rio Tietê [no specific locality]; CESP, Aug–Oct 1979. LBP 30183 (3, 291.0–335.0 mm SL), Borebi, rio Claro , 22º45′39′′S, 49º2′18′′W; A.B. Nobile & F.P. Lima, 7 March 2020. LBP 84 (15, 111.6– 326.3 mm SL), Itatinga, Jurumirim reservoir, rio Paranapanema , c. 23º20′S, 48º34′W; C. Oliveira, R. Devidé & M.L. Carvalho, 14 June 1995. LBP 2711 (4, 175.0– 200.0 mm SL), Itatinga, Jurumirim reservoir, rio Paranapanema , c. 23º20′S, 48º34′W; R. Devidé, 20 Dec 1999. LBP 6481 (6, 253.0–267.0 mm SL), Itatinga, Jurumirim reservoir, rio Paranapanema , c. 23º20′S, 48º34′W; N.S. Marques, 11 June 2008. LBP 13305 (1, 114.4 mm SL), Angatuba, Jurumirim reservoir, Lago do Coqueiral , rio Paranapanema , 23º29′35′′S, 48º37′7′′W; G. Kurchevski & F.P. Lima, 7 Apr 2011. LIRP 8946 (1, 330.0 mm SL), Ourinhos, rio Paranapanema, UHE Ourinhos (fish ladder), 23º4′12′′S, 49º50′17′′W; T.N. Pereira, 15 Jul 2009. MZUSP 45274 (7, 115.0–220.0 mm SL), rio Paranapanema [no specific locality]; CESP, 14–20 May 1979. FMNH 3418 (5, 97.8–117.9 mm SL): “ Sao Paulo ”; H.E. Williams, Sept 1900. MZUSP 1967 (3, 156.0– 157.1 mm SL); MZUSP 2011 (1, 206.0 mm SL), “S ã o Paulo ”; no collector specified, 1902–1905. Paraná: MZUSP 21615 (1, 169.0 mm SL), rio Paraná, Guaíra (above Sete Quedas falls ), c. 24º4′S, 54º15′W; CETESB, 1977–1980. NUP 1892 (3, 121.2– 155.4 mm SL), Querência do Norte , rio Paraná, c. 22º59′S, 53º36′W; Nupélia, 23 Aug 1989. NUP 1893 (3, 90.2–207.1 mm SL), Porto Rico , c. 22°46′S, 53°15′W; Nupélia, 1983–1993. MZUSP 21080 (1, 225.0 mm SL), rio Paraná, below Sete Quedas falls , c. 24º7′S, 54º20′W; CETESB, 1977–1980. MZUSP 374 (1, 237.0 mm SL), Castro , c. 24º47′S, 50º0′W; E. Garbe, 1907. Paraguay: MZUSP 19852 (1, 276.0 mm SL), Depto. Alto Paraná, río Monday , c. 25º35′S, 54º37′W; CETESB, July–Aug 1977. MZUSP 82102 (1, 98.3 mm SL), Depto. Alto Paraná, dam at río Acaray, north to Ciudad del Leste , km 7 of road 14, c. 25º27′S, 54º39′W; C. Dlouhy, April 1982. USNM 247317 (1, 93.9 mm SL): Depto. Alto Paraná, reservoir on dam at río Acaray ; L. Naylor & B. Abrell, 16 May 1982. Incorrect localities: MNRJ 13400 (1, 186.9 mm SL), “Manaos”; Comiss ã o Rondon, 1909. CAS 20367 (1, 163.6 mm SL), “ Ilha Grande, Rio de Janeiro ”; no collector specified, 1905.

Figures

FIGURE 8. Salminus hilarii: (A) lectotype, MNHN A.8658, 165.9 mm SL, “rio San Francisco”; (B) ANSP 69608, 182.0 mm SL, Brazil, Ceará, rio Jaguaribe; holotype of Brycon erythrura Fowler (photo by Kyle Luckenbill; left side, reversed).

FIGURE 9. Salminus hilarii: (A) MZUSP 86921, 329 mm SL, Brazil, São Paulo, rio Tietê; (B) MZUSP 53461, 220.4 mm SL, Brazil, São Paulo, rio do Peixe; (C) MZUSP 47467, 141.1 mm SL, Brazil, Minas Gerais, rio Verde.

FIGURE 10. Salminus hilarii, living/freshly collected specimens. (A) MZUSP 86921, 329 mm SL, Brazil, São Paulo, rio Tietê; (B) Brazil, Minas Gerais, Furnas reservoir; (C) Brazil, Minas Gerais, rio Paraopeba. Photo A by J.C. Nolasco, B by A.K. Zeinad, and C by G.N. Salvador.

FIGURE 11. Map of eastern Brazil, showing the distribution of Salminus hilarii (red dots).