The influence of aestivation in land snails on the larval development of Muellerius cf. capillaris (Metastrongyloidea: Protostrongylidae).

The larval development of Muellerius cf. capillaris in aestivating Trochoidea seetzenii and Theba pisana was delayed: in the first snail 82% of the parasites remained as second-stage larvae (L2) after as much as 90 days, and in the second snail 60% remained as L2 after 50 days. Reactivation of T. seetzenii after 59 days of aestivation caused the larvae to develop to the third stage (L3). The number of recovered larvae among T. seetzenii was consistently higher in active vs aestivating snails (P < 0.05). Such differences were not evident among T. pisana (P > 0.05). In active T. pisana, larval development was faster than in active T. seetzenii, whereas there were no such differences between aestivating snails of these 2 species. Aestivating infected T. seetzenii had lower body weights than same-size active non-infected, as well as infected snails. Aestivating infected T. pisana were not weighed, but they too exhibited poor body condition.