Bryconamericus scleroparius (Regan, 1908)

Mirande, Juan Marcos, 2010, Phylogeny of the family Characidae (Teleostei: Characiformes): from characters to taxonomy, Neotropical Ichthyology 8 (3), pp. 385-568 : 520

Bryconamericus scleroparius clade

Bryconamericus brevirostris (Günther) ?, B. emperador (Eigenmann & Ogle) ?, B. guaytarae Eigenmann & Henn ?, B. loisae (Géry) ?, B. multiradiatus Dahl ?, B. peruanus (Müller & Troschel) ?, B. scleroparius , B. simus (Boulenger) ?, B. terrabensis Meek ?, B. zeteki Hildebrand ?.

Bryconamericus scleroparius was included in the Astyanax clade in the hypothesis of Mirande (2009). In this study instead this species is the sister group of a large clade of characids composed of the subfamilies Aphyocharacinae , Aphyoditeinae , Cheirodontinae , Gymnocharacinae , and Stevardiinae . Bryconamericus scleroparius shares with B. brevirostris , B. emperador (with eight or nine branched dorsal-fin rays), B. peruanus , B. scopiferus guaitarae (= B. guaytarae ), and B. simus ( Eigenmann, 1917) the presence of nine branched dorsal-fin rays and a relatively high number of anal-fin rays. Géry (1977) included these species plus B. caucanus Eigenmann , B. loisae , B. multiradiatus , B. phoenicopterus (Cope) , B. terrabensis , and B. zeteki in a Bryconamericus peruanus group, defined by the relatively high number of anal-fin rays, but not necessarily having nine branched dorsal-fin rays. Among these species, Bryconamericus caucanus and B. phoenicopterus have only eight branched dorsal-fin rays (as in true Bryconamericus ), according to Eigenmann (1917), and these two species are not putatively considered in this clade. Román-Valencia (2000) mentioned that Bryconamericus dahli has between 8 and 10 branched dorsal-fin rays. Such intraspecific variation is rare among characids, but this species is also tentatively included in this clade. As Bryconamericus exodon , the type species of the genus, is included in the Stevardiinae , B. scleroparius and close relatives should be transferred to another genus. Eretmobrycon bayano Fink , transferred to Bryconamericus by Román-Valencia (2000) has also 9 branched dorsal-fin rays, at least in some individuals ( Román-Valencia, 2002). Bryconamericus bayano is phylogenetically related to Bryconamericus emperador and B. scleroparius according to Román-Valencia & Vanegas-Ríos (2009). Although that hypothesis was based only in a molecular Maximum Likelihood approach and they did not propose synapomorphies relating these species, it constitute the single reference about the relationships of B. bayano . According to the results obtained herein and considering the hypothesis of Román-Valencia & Vanegas-Ríos (2009), it is possible that Eretmobrycon should have to be resurrected to include not only B. bayano but also B. scleroparius and close relatives.

Autapomorphies of Bryconamericus scleroparius :

1. Rhinosphenoid (47): (1> 0) absent. Reversal of synapomorphy 2 of the Characidae . Paralleled in nodes 207, 260, 280, and 298 and in Aphyocharax nattereri , Attonitus ephimeros , Brycon orbignyanus , Hollandichthys multifasciatus , Pseudocorynopoma doriae , and Salminus brasiliensis .

2. Branching of laterosensory canals of fourth or fifth infraorbitals (74): (0> 1) present. Paralleled in the Bryconops clade, in nodes 167, 177, 218, 260, and 276, and in Chalceus macrolepidotus and Piaractus mesopotamicus .

3. Foramen in posterior region of metapterygoid (168): (1> 2) in form of incomplete arch, bordered posteriorly by hyomandibula. Reversal of synapomorphy 10 of node 205. Paralleled in Pseudocorynopoma doriae .

4. Position of ventral end of posttemporal (253): (0> 1) posterior to lateral margin of epioccipital. Paralleled in nodes 211 and 228 and in Hoplias cf. malabaricus , Markiana nigripinnis , Probolodus heterostomus , and Prochilodus lineatus .

5. Number of branched anal-fin rays (288): (0> 1) 25 or more. Reversal of synapomorphy 3 of node 200. Paralleled in nodes 208, 255, and 263 and in Nematobrycon palmeri .

6. Uroneurals (306): (0> 1) two pairs. Reversal of synapomorphy 15 of node 205. Paralleled in the Tetragonopterinae , in nodes 276 and 300, and in Galeocharax humeralis and Markiana nigripinnis .