Larval trematodes (Brachylaemidae) from the slugs Milax sowerbii (Férussac), Agriolimax reticulatus (Müller) and Arion lusitanicus Mabille

Abstract

1. Metacercariae are recorded from the kidney tissues of slugs. Over 3000 slugs belonging to ten species were examined. Infection was confined to Milax sowerbii (Férussac) and Agriolimax reticulatus (Müller) apart from a few infected specimens of Arion ater (Linnaeus) or A. lusitanicus Mabille. Only one sporocyst was discovered and this occurred in A. lusitanicus.2. Four distinct stages in metacercarial development are described—the caudal stage (0·7 × 0·3 mm.), the feeding stage (0·9 × 0·5 mm.), the corrugated stage (1·3 × 0·7 mm.) and the mature metacercaria (2·5 × 1·0 mm.). The corrugated stage is so-named because of the distinctive appearance of its cuticle.3. Both the cercaria and metacercaria belong to the genus Brachylaemus (Dujardin, 1843) Blanchard 1847 and they probably belong to the same species. Since the life history is not known, no trivial name has been given to the organism.