Description of adult and larva of Ichnestoma pringlei n. sp (Coleoptera Scarabaeidae Cetoniinae), with notes on its biology and ecology

There are at present 10 described species in the primitive genus Ichnestoma Gory & Percheron 1833. These are all phylogenetic and geographic relicts o f high evolutionary and conservation interest. The discovery of a new speci es, I. pringlei n. sp., and the first description of a larva (third instar) of this genus are reported here. New information is also presented on thei r life-cycle and on the dependence of their activities on rainfall patterns , particularly in the semi-arid region of the Karoo. In this region, larvae seem to take 2 years to complete growth and metamorphosis since they feed only after major rainfall events, while remaining inactive and deep undergr ound during dry periods. Adults emerge from their cocoons only after summer rains of at least 15 mm. They lack functional mouth parts and are unable t o feed. Their life span is only 3-5 days. Because females are completely fl ightless and unable to disperse, species of the genus are extremely vulnera ble to environmental degradation. It seems likely that they may play a key role in the decomposition of dead plant matter, especially in dry and clay- rich soils where other primary decomposers are scarce.