Brycon devillei ( Castelnau, 1855 )

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 : 51-53

Brycon devillei ( Castelnau, 1855)

Chalceus devillei Castelnau, 1855: 69 , pl. 36, fig. 2 (Type locality “ Bahia”). Brycon devillei: Howes, 1982: 24 –25, fig. 17 (holotype; brief description). [not Amaral-Campos, 1950; Araújo, 1996; Sunaga & Verani, 1991; Vieira et al., 2008; Azevedo et al., 2011; Travenzoli et al.,

2015]

Summary information on meristics. Lateral line scales 53. Horizontal scale rows between dorsal-fin origin and lateral line 9. Horizontal scale rows between lateral line and pelvic-fin 4. Circumpeduncular scales 18. Dorsal-fin rays ii, 9. Pectoral-fin rays i, 13. Pelvic-fin rays i, 7. Anal-fin rays iii, 23. Outer premaxillary teeth row with 10 teeth. Four teeth in second, inner premaxillary row, plus 2 teeth between the first and third rows. Fifteen dentary teeth at the main series. Twenty-five maxillary teeth. First branchial arch with 13 lower, 1 at angle, and 12 upper gill rakers. Morphometric data of the holotype presented in Table 8 .

Remarks. Brycon devillei is only known from its holotype ( MNHN 4517 ), which has as its stated type-locality “ Bahia ” . Castelnau, who collected and described the species, spent a year as the French consul in Salvador (the capital city of Bahia) in 1849 ( Papavero, 1971). “ Bahia ” was often used in the XIX zoological and botanical literature to refer to Salvador and surrounding areas . No Brycon specimens were examined in the present study from the northern coastal river systems adjacent to Salvador, with the exception of a single B. vonoi specimen apparently collected immediately southward from Salvador at the rio Una (see item “Remarks” of B. vonoi , below). The holotype of Brycon devillei is distinct from B. vonoi by possessing a distinctly pointed head profile (vs. head profile relatively blunt), a fifth infraorbital bone considerably wider than high (vs. fifth infraorbital bone about as wide as high; see Fig. 6 ), and a higher number of horizontal scale rows between dorsal-fin origin and lateral line (9, vs. 7–8). Overall, the holotype of Brycon devillei is very similar and virtually undistinguishable from B. insignis , a species occurring considerably southward, in the rio Paraíba do Sul and coastal river systems from Rio de Janeiro, eastern Brazil (see item “Distribution” of B. insignis , above). Castelnau stayed in Rio de Janeiro during June to October of 1843 ( Papavero, 1971) and collected some fishes in the area (e.g., the holotype of Loricariichthys castaneus , a species restricted to coastal river systems from rio Doce basin southward to rio Ribeira de Iguape basin in eastern Brazil ; Reis & Pereira , 2000). Kullander & Lucena (2006: 134) remarked that the type-locality of Crenicichla lacustris , said to have been collected at “ Bahia ” by Castelnau (1855), was probably an error, since the species was never collected so far northward into the northern coastal rivers of Bahia, the most setentrional known locality being the rio Buranhém in southern coastal Bahia . They proposed that the holotype of Crenicichla lacustris was more likely collected in the Rio de Janeiro area, where the species is in fact quite common ( Kullander & Lucena, 2006: 134). It seems also possible that the holotype of Brycon devillei was collected in the Rio de Janeiro area, instead of Bahia . In that case, Brycon devillei would have to be considered a senior synonym of B. insignis . However, given our current lack of knowledge on the Brycon populations occurring in the coastal river systems north from the rio Pardo , it seems more cautious to await for additional information on the Brycon species occurring in the area, before proposing such a change. To complicate further the issue, at least one specied described by Castelnau (1855) bearing the locality “ Bahia ”, was demonstrated to be based on specimens very likely collected in rivers draining the southern portion of Bahia state ( Silva & Malabarba, 2016). Until the matter can be satisfactorily settled, we prefer to consider Brycon devillei as a species inquirenda.

Material examined. MNHN 4517 (1, 145.5 mm SL): “ Bahia ”. F. de Castelnau, no date. Holotype of Chalceus devillei Castelnau.

Figures

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.

Tables

TABLE 8. Morphometric data of the holotype of Brycon devillei, MNHN 4517.

Standard length (SL)		145.5
Percentages of standard length
Depth at dorsal-fin origin		26.8
Snout to dorsal-fin origin		55.3
Dorsal-fin base length		12.1
Posterior terminus of dorsal fin	to adipose fin	23.1
Posterior terminus of dorsal fin	to hypural joint	38.1
Snout to pelvic-fin insertion		48.2
Snout to anal-fin origin		65.9
Anal-fin base length		26.3
Caudal peduncle length		14.6
Dorsal-fin height		23.2
Pectoral-fin length		20.4
Pelvic-fin length		16.5
Caudal peduncle depth		8.4
Head length		27.5
Percentages of head length
Head height		69.0
Snout length		30.8
Upper jaw length		48.0
Horizontal eye diameter		24.3
Post-orbital length		46.3
Least interorbital width		31.3