title: A new Hyphessobrycon (Ostariophysi: Characiformes: Characidae) from the middle Amazon basin, Brazil.
abstract: Hyphessobrycon montagi, new species, is described from tributaries of the Rio Arapiuns, a left margin affluent of the lower Rio Tapajós, Amazon basin, Pará, Brazil. The new species can be diagnosed from all its congeners by the possession of a combination of two well-defined humeral blotches, connected by a narrow stripe, and a caudal peduncle blotch. A putatively monophyletic Hyphessobrycon heterorhabdus species-group, restricted to H. heterorhabdus, H. amapaensis, and H. eschwartzae, is herein proposed based on shared derived features of color pattern. Alternative proposals of a "Hyphessobrycon heterorhabdus group" presented in the recent literature are evaluated and criticized.
authors.affiliation: Museu de Zoologia da Universidade Estadual de Campinas "Adão José Cardoso", Caixa Postal 6109, 13083-863, Campinas, SP, Brazil.; Email: fctlima@gmail.com.
authors.forename: Flávio C T
authors.initials: FC
authors.lastname: Lima
authors.affiliation: Universidade Federal do Piauí, Campus Profª. Cinobelina Elvas, Bom Jesus, PI, Brazil.; Email: dpcoutinho@ufpi.edu.br.
authors.forename: Daniel P
authors.initials: DP
authors.lastname: Coutinho
authors.affiliation: Museu Paraense Emílio Goeldi, Caixa Postal 399, 66040-170, Belém, PA, Brazil.; Email: wolmar@museu-goeldi.br.
authors.forename: Wolmar B
authors.initials: WB
authors.lastname: Wosiacki
mesh_terms: D058500:Animal Fins / Q000033:anatomy & histology; D000818:Animals; D001938:Brazil; D060126:Characidae / Q000033:anatomy & histology* / Q000145:classification; D017753:Ecosystem; D005260:Female; D008297:Male; D009055:Mouth / Q000033:anatomy & histology; D014070:Tooth / Q000033:anatomy & histology