Pulmonata

The genus Peronia Fleming, 1822 includes all the onchidiid slugs with dorsal gills. Its taxonomy is revised for the first time based on a large collection of fresh material from the entire Indo-West Pacific, from South Africa to Hawaii. Nine species are supported by mitochondrial (COI and 16S) and nuclear (ITS2 and 28S) sequences as well as comparative anatomy. All types available were examined and the nomenclatural status of each existing name in the genus is addressed. Of 31 Peronia species-group names available, 27 are regarded as invalid (twenty-one synonyms, sixteen of which are new, five nomina dubia, and one homonym), and four as valid: Peronia peronii (Cuvier, 1804), Peronia verruculata (Cuvier, 1830), Peronia platei (Hoffmann, 1928), and Peronia madagascariensis (Labbé, 1934a). Five new species names are created: P. griffithsi Dayrat & Goulding, sp. nov., P. okinawensis Dayrat & Goulding, sp. nov., P. setoensis Dayrat & Goulding, sp. nov., P. sydneyensis Dayrat & Goulding, ...

Shell variability of the steppe mollusk Chondrula tridens from 18 micropopulations in the forest–
steppe zone of the Volga Upland was studied. It was found that larger specimens of C. tridens with welldevel
oped teeth inhabit the central and eastern parts of the territory. Specimens in the northwestern part of the
upland are characterized by small shells, the highest degree of roundness, and mostly reduced teeth in the
mouth. The main factors that determine variability in the size and proportions of shells are the average daily
temperatures increasing from the northwest to the south, the reduction in the total precipitation, the decrease
in the soil moisture content, and, possibly, the increased content of carbonates in the soil.