title: The morphology of free-living stages and immature parasites of Rhabdias paraensis (Nematoda: Rhabdiasidae), a parasite of Rhinella marina (Anura: Bufonidae) in Brazil.
abstract: Rhabdias paraensis Santos, Melo, Nascimento, Nascimento, Giese et Furtado, 2011 was described based on fully gravid worms. Further investigations on the free-living stages, immature worms and young individuals were facilitated by cultivation in the laboratory, which allowed us to add new information about the morphology and development of the species. Observations on the free-living development of R. paraensis showed that the life cycle is typical of Rhabdias, with alternation of gonochoristic and hermaphroditic generations and without homogony. Males of the free-living generation were different from those in several species of the genus studied previously. In the original description, the excretory glands and duct were absent in gravid specimens of R. paraensis, while in this study, distinct excretory glands and a duct were observed in immature and young individuals. Additionally, we recognised the separation of the buccal capsule walls into anterior and posterior portions and described the specific shapes of these portions in lateral and apical view. Studies on the morphology and development of free-living stages of Rhabdias spp. from Neotropical regions may provide additional information for species determination.
authors.forename: Francisco Tiago de Vasconcelos
authors.initials: FT
authors.lastname: Melo
authors.forename: Luciana de Cássia Silva
authors.initials: Lde C
authors.lastname: do Nascimento
authors.forename: Lilian Cristina
authors.initials: LC
authors.lastname: Macedo
authors.forename: Jeannie Nascimento
authors.initials: JN
authors.lastname: dos Santos
authors.forename: Yuriy
authors.initials: Y
authors.lastname: Kuzmin
mesh_terms: D000825:Animal Structures / Q000033:anatomy & histology; D000818:Animals; D001938:Brazil; D002024:Bufo marinus / Q000469:parasitology*; D005260:Female; D008297:Male; D008853:Microscopy; D017172:Rhabditoidea / Q000033:anatomy & histology* / Q000302:isolation & purification