title: The annual reproductive cycle of the snail Megalobulimus abbreviatus (Bequaert, 1948) (Gastropoda, Pulmonata).
abstract: Morphological changes in the sexual organs of the pulmonates were observed throughout a year and correlated with reproductive-cycle periods. Reproductive-organ weights of the snail Megalobulimus abbreviatus were recorded seasonally and gonad sections were analyzed morphologically. The weights were used to obtain the organosomatic index. Mean oocytic diameter and oocytic maturation index were based on gonad sections. It was concluded that M. abbreviatus is an iteroparous snail whose annual reproductive cycle is characterized by mating and egg laying throughout spring and early summer, and also by reproductive system preparation, occurring over the remainder of the summer until the end of winter, for a new breeding season.
authors.affiliation: Laboratório de Histofisiologia Comparada, Departamento de Ciências Morfológicas, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, Brazil. angelocmh@terra.com.br
authors.forename: A C M
authors.initials: AC
authors.lastname: Horn
authors.forename: A
authors.initials: A
authors.lastname: Achaval
authors.forename: D M
authors.initials: DM
authors.lastname: Zancan
mesh_terms: D000818:Animals; D005260:Female; D006066:Gonads / Q000166:cytology / Q000254:growth & development*; D008297:Male; D012098:Reproduction / Q000502:physiology; D012621:Seasons; D012908:Snails / Q000502:physiology*