Taxonomy and natural history of 18 Ropalidia species (Hymenoptera, Vespidae) of Madagascar

Abstract

Eighteen species of Ropalidia Guérin-Méneville, 1831 of Madagascar are treated, viz. those of which females and males were found together on one or more nests in the 1970s. The main purpose is to define the species by male and female characters since the latter alone are insufficient to distinguish closely related species. Ten new species are described: R. cocoscola, R. cauponae, R. merina, R. mysterica, R. favulorum, R. kojimai, R. rosae, R. cincinnata, R. perplexa and R. linearecta. R. flavoviridis Kojima, 1998 is a valid species, not a synonym of R. dubia (de Saussure, 1853). Seven species are redescribed with emphasis on male characters: R. shestakowi (von Schulthess, 1931), R. grandidieri (de Saussure, 1890), R. variabilis (de Saussure, 1890), R. phalansterica (de Saussure, 1853), R. carinata (de Saussure, 1890), R. dubia (de Saussure, 1853) and R. fraterna (de Saussure, 1900). Field notes on shape and location of nests are summarized and numbers of foundresses and subdominant females, as far as determined by dissection, reported. Various eulophid and tachinid parasitoids emerged from the nests; an attack by the ichneumonid Hemipimpla pulchripennis (de Saussure, 1890) is described.