Stichonodontinae Eigenmann, 1910

Melo, Bruno F, Ota, Rafaela P, Benine, Ricardo C, Carvalho, Fernando R, Lima, Flavio C T, Mattox, George M T, Souza, Camila S, Faria, Tiago C, Reia, Lais, Roxo, Fabio F, Valdez-Moreno, Martha, Near, Thomas J & Oliveira, Claudio, 2024, Phylogenomics of Characidae, a hyper-diverse Neotropical freshwater fish lineage, with a phylogenetic classification including four families (Teleostei: Characiformes), Zoological Journal of the Linnean Society (Zool. J. Linn. Soc.) 202 (1), pp. 1-37 : 22

Stichonodontinae Eigenmann, 1910 , new usage

Type genus: Stichonodon Eigenmann, 1903 .

Included genera: Hasemania , Hemigrammus (in part), Hyphessobrycon (in part), Moenkhausia (in part), Nematocharax Weitzman, Menezes and Britski, 1986 , and Stichonodon .

Definition: The least inclusive crown clade that contains Stichonodon insignis , Moenkhausia xinguensis (Steindachner, 1882) , and Hyphessobrycon stegemanni Géry, 1961 . This is a minimum-crown-clade definition. See Figure 5 for a reference phylogeny of Stichonodontinae.

Etymology: From the ancient Greek στίΧος (stˈiːko͡ʊz) meaning a row or line of soldiers or a line of poetry and ὀδών (ˈo͡ʊdɑːn) meaning tooth.

Remarks: The phylogeny inferred from the UCE loci resolves Stichonodontinae as monophyletic ( Fig. 5), reflecting previous analysis of molecular characters (Mariguela et al. 2013, Betancur-R et al. 2019, Melo et al. 2022a). Moenkhausia is paraphyletic with one clade containing M. britskii Azevedo-Santos and Benine,2016 , M.grandisquamis (Müller and Troschel, 1845) , M. pankilopteryx Bertaco and Lucinda, 2006 , M. surinamensis Géry, 1965 , M. xinguensis (Steindachner, 1882) (type species of Moenkhausia ), and M. restricta Soares and Benine, 2019 , whereas the other clade includes M. abyss Oliveira and Marinho, 2016 , M. costae (Steindachner, 1907) , M. dichroura (Kner, 1858) , M. heikoi Géry and Zarske, 2004 , M. intermedia Eigenmann, 1908 , M. ischyognatha Petrolli and Benine, 2015 , M. lata Eigenmann, 1908 , M. sthenosthoma Petrolli and Benine, 2015 , and Stichonodon insignis (type and only species of the genus). Moenkhausia lepidura (Kner, 1858) , M. nigromarginata Costa, 1994, and Nematocharax oenustus Weitzman et al., 1986 (type species of the genus) are successive branching lineages leading to a clade containing Hasemania , species currently classified with Hemigrammus and Moenkhausia , Hemigrammus sp. Leticia, Hyphessobrycon stegemanni Géry, 1961 , and Hyphessobrycon sp. Araguaia ( Fig. 5).

Similar to several characid genera, Moenkhausia is traditionally characterized by a combination of characters that include five multicuspid teeth in the inner premaxillary series, caudal fin partially covered by scales, and complete lateral line (Eigenmann 1917). Hasemania is diagnosed by the absence of the adipose fin (Ellis 1911). Stichonodon differs from other characids by the keel-shaped ventral area, two series of teeth in the premaxilla,

and dentary in a single series of teeth (Eigenmann and Myers 1929). Nematocharax is diagnosed by a combination of elongate branched rays of the dorsal, pelvic, and anal fins, two rows of premaxillary teeth in adults, and an almost complete row of teeth along the free ventral maxillary border (Weitzman et al. 1986). However, all these characters are polymorphic in these lineages, requiring the proposal of new diagnoses based on shared derived features among species within these monophyletic groups. Stichonodontinae probably originated in the Amazon– Orinoco–Guianas with multiple transitions to La Plata and upland rivers of the São Francisco and Atlantic coastal drainages ( Fig. 5).