Cheumatopsyche concava

13. Cheumatopsyche concava species group

Species in this group are characterised by having a unilobed segment X with apicoventral setal lobes almost completely fused with segment X (Fig. 13). All processes or lobes on segment X are fused, except for the pair of small, wart-like, more or less elevated, lateral setose areas. The pair of apicoventral setal lobes are usually fused with the apicolateral margins of segment X, and are delineated only by their setose surfaces. The dorsal and lateral interlobular gaps are absent. The pair of wart-like lateral setose areas, the vestigia of the preanal appendages, are located centrally on segment X. The spiny ventrocaudal spiny lobe on segment IX are present or absent. This species group is distributed in South and South-East Asia, including the South-East Asian archipelago.