Organisms
Research Projects	Research Group	Organisms	Collection	DNA Labs
Albinaria land snails I first came across the genus Albinaria when it was suggested to me by Edi Gittenberger as a possible project for my MSc. Taking his advice, I spent a year studying the distribution and evolution of the Albinaria species of Central Crete. I then went on to do my PhD on the species complex of A. hippolyti. The text below is taken from my PhD thesis. Shells of ten endemic central-Cretan Albinaria species   An aggregate of aestivating A. corrugata.   Albinaria snails belong to the family Clausiliidae. Like all members of this family, they have slender, spindle-shaped shells with a complex of folds and lamellae in the aperture. These folds partly serve to support the clausilium, a protective, door-like structure and a unique characteristic of the Clausiliidae. The genus occurs all over Greece, Cyprus, and parts of Turkey and the Lebanon. Our knowledge of its ecology and life-history is still relatively fragmentary, but the following outline may serve as a well-established summary. The snails live on limestone rocks, where they feed on the microflora. They are active only during the wet season, that is, in Mediterranean lowlands, from November through April. Eggs are laid shortly after the beginning of the wet season. The development from a juvenile to a fully-grown shell takes two to three wet seasons. During the intermittent dry seasons, the snails, young and adults alike, aestivate ("the warm weather equivalent of hibernation"--Gould, 1985) on the rocks or in crevices inside the rocks. For aestivation, aggregates are often formed, sometimes reaching sizes of many hundreds of individuals. During the last dry season prior to sexual maturation, the subadult snail (the shell of which is already fully developed, albeit thinner than that of an adult) increases the size of its genital organs while thickening the shell wall. At the end of this process, with shell wall and genitalia fully formed, the animal is considered adult. Copulation then takes place during the first weeks of autumn rains. Population densities can sometimes be very high, in spite of heavy predation by beetle larvae of the family Drilidae. These insects attack the snails during their aestivation, by perforating the shell and eating the snail inside. In all, almost 100 species are currently recognised in Albinaria, each with its own characteristic morphology. Some of these are relatively uniform and wide-spread, such as certain species from the Pelopónnisos and mainland Greece. Others are much more localised and restricted to a single valley or to an islet, or wide-spread but subdivided into many subspecies. One of the most conspicuous features of their distributions, is the general lack of geographical overlap. In other words, at any one locality, only one of these 100 species is usually found. In some cases two species may be present, but rarely more. It seems that the whole genus' range is divided into a sort of patchwork, with all species fulfilling equivalent ecological roles in their respective patches. This has led Gittenberger (1991) to suggest that the Albinaria radiation is a non-adaptive one, as opposed to the classical examples of adaptive radiations, where the diversification is both morphological and ecological. A Drilus (Coleoptera: Drilidae) larva emerging through the perforation it made in the shell of its prey, an Albinaria spratti (photo: J. Goud). Aperture of a shell of A. corrugata inflata, partly opened up to show the arrangements of folds and lamellae and the clausilium. A newly-hatched Albinaria spratti in a laboratory cage.   A clutch of Albinaria christae eggs, laid in a laboratory cage.   Related websites: Francisco Welter-Schultes' sites on Albinaria research and Albinaria bibliography (both highly recommended!)