The continental malacofauna of Arabia and adjacent areas, VII. The family Achatinidae (Coeliaxinae, Subulininae) in the Socotran Archipelago (Gastropoda, Pulmonata).

The endemic fauna of achatinoid terrestrial molluscs for the Socotran Archipelago (Yemen) is revised. The main group falls into two genera, viz. Riebeckia E. v. Martens, 1883 with five species and Balfouria Crosse, 1884 with seven species, two of which are here described as new to science, i.e. Balfouria nitida n. sp., and Balfouria minima n. sp. Another globally distributed species could be found, and the endemic Zootecus species of the outer island of Abd el-Kuri is illustrated. The highly specialised shell structure of Balfouria is discussed, which is used to camouflage the animals with a mixture of clay and mucus protecting the shell during the individual lifetime of a specimen. [ABSTRACT FROM AUTHOR]