Estratégia de história de vida e recaracterização morfológica Sarasinula linguaeformis (Semper, 1885) (Eupulmonata, Veronicellidae)

Abstract

Veronicellidae includes the only native slugs in Brazil, unlike the other slugs with occurrence in the national territory which are all introduced species. This family is characterized by great diversity and wide distribution. However, it can be considered as a neglected group, since the knowledge about morphological, biological and ecological aspects is restricted to few genera and species. These gastropods are hermaphrodites, but little is known about the relative success of self-fertilization and cross-fertilization. In the present work we performed a morphological and morphometric study of. S. linguaeformis, as well as the revision of the distribution of Sarasinula spp. in Brazil. We also have characterized the life history strategy of this species. The results revealed considerable morphological variability among individuals and a wide distribution of the group in the Brazilian territory. We also investigated the following life history traits: growth, time to sexual maturity, number of eggs per reproductive event, hatchability, and mortality. The isolated slugs presented higher values of the linear measurements taken for the notum, hyponotum and pedal gland, compared to the paired slugs. On the other hand, paired individuals reached maturity earlier, with a minimum of 158 days, whereas isolated individuals reached maturity at least at the age of 181 days. Paired snails performed a greater number of reproductive events (84), producing in average 57 eggs/event; while isolate snails perform only 12 reproductive events, producing 17 eggs/event. Our results showed that self-fertilization is not a successful reproductive strategy of S. linguaeformis and that slugs in the presence of coespecifics invest energy in reproduction while in the absence of coespecifics they invest in growth.