Non-marine mollusks of the northern Narinda karst, north-western Madagascar

The non-marine mollusc fauna of the northern part of t1he Narinda karst of north-western Madagascar, mostly from the Anjajavy Peninsula and Analalava District is enumerated based on collections made in the past 20 years. 102 species are recorded (73 terrestrial, 12 freshwater and 17 littoral). Twenty four are described as new species: Omphalotropis lavanensis n. sp., Boucardicus crassus n. sp., Boucardicus malama n. sp., Boucardicus minoratus n. sp., Cyclotopsis pectinata n. sp., Tropidophora narindana n. sp., Tropidophora tenona n. sp., Tropidophora jugia n. sp., Tropidophora neoliratoides n. sp., Tropidophora rovidrovitra n. sp., Gulella foucaultia n. sp., Gulella martiniana n. sp., Gulella anjajavyensis n. sp., Gulella volontany n. sp., Gulella antonibe n. sp., Parvedentulina lavana n. sp., Microcystis zorony n. sp., Microcystis embertoni n. sp., Sitala dickensi n. sp., Ctenophila tangolika n. sp., Kalidos unistriata n. sp., Kalidos quadrangulata n. sp., Kalidos narindana n. sp., and Kalidos mahafatifaty n. sp. A further six are new records for Madagascar. We propose two changes of genera and one new synonym. Madagascar’s dry forest continues to decline in area and much of the forest in the region is fragmentary. Three species were only recorded from old shells and may be locally extinct.