Data are presented on aspects of the group structure anc! social behaviour of warthogs Phacochoerus aethiopicus (Pallas, 1767) in the Andries Vosloo Kudu Reserve (AVKR), Eastern Cape Province, South Africa. The social structure of warthogs is one of small groups, usually solitary males or bachelor groups, matriarchal groups consisting of adult females with juveniles and/or yearlings, or yearling groups. Mean group size was 2.21. Forty five percent of warthogs sighted were solitary. There was a seasonal variation in the mean group size. Differences in social interactions between various age and sex classes are described. Breeding of the warthogs in the AVKR was seasonal with the females coming into oestrus at the end of May and farrowing towards the end of November. The mating system is promiscuous with males roaming during the mating season, mating with numerous females, and females mating with more than one male. Non-offspring nursing occurred.
The following new taxa are described and illustrated, Oryzaephilus euneutus sp. nov., from Namibia and the Republic of South Africa, Oryzaephilus mucronatus sp. nov., from Namibia, Afronausibius pumilus sp. nov., from Gabon and Cameroon, Metacorimus - mroczkowskii gen. et sp. nov., from Cameroon, and Saunibius moyseyi gen. et sp. nov., from Sudan and Ghana.