title: A new species of Pisionidens (Aiyar & Alikunhi, 1943) (Annelida: Sigalionidae) from Southeastern Brazil.
abstract: Herein we describe specimens found along the southeastern coast of Brazil which belong to a new species, P. caissara sp. nov. This species differs from the other species of the genus by the glabrous antennae and palps, proboscis extending up to the sixth segment, jaws with smooth cutting edge and a pair of lateral wing-like sheaths, two pairs of seriate male copulatory organs, first pair of testes on segment 19 and ovaries from segment 26 onward. Reproductive characters commonly used for characterizing species are also discussed.
authors.affiliation: Programa de Pós-Graduação em Biologia Marinha e Ambientes Costeiros, Universidade Federal Fluminense; CEP: 24020-141, Outeiro de São João Batista, Niterói, Rio de Janeiro, Brazil.; Email: vrmiranda@ig.com.br.
authors.forename: Vinícius Da Rocha
authors.initials: VD
authors.lastname: Miranda
authors.affiliation: Departamento de Biologia Animal, Universidade Federal Rural do Rio de Janeiro; Caixa Postal 74524; CEP 23851-970, Seropédica, Rio de Janeiro, Brazil.; Email: acbrasil@gmail.com.
authors.forename: Ana Claudia Dos Santos
authors.initials: AC
authors.lastname: Brasil
authors.affiliation: Departamento de Biologia Marinha, Universidade Federal Fluminense; CEP: 24020-141, Outeiro de São João Batista, Niterói, Rio de Janeiro, Brazil.; Email: cinthyasantos@id.uff.br.
authors.forename: Cinthya Simone Gomes
authors.initials: CS
authors.lastname: Santos
mesh_terms: D063147:Animal Distribution; D000825:Animal Structures / Q000033:anatomy & histology / Q000254:growth & development; D000818:Animals; D049628:Body Size; D001938:Brazil; D017753:Ecosystem; D005260:Female; D008297:Male; D009929:Organ Size; D011077:Polychaeta / Q000033:anatomy & histology / Q000145:classification* / Q000254:growth & development