The solitarily living Stegodyphus africanus and S. sabulosus we found in the field also as parasites in colonies of S. dumicola. Neotenic interspecific tolerance leaves S. dumicola defenseless against hostile congeneric species.

Female and male S. dumicola                    Female S. africanus    © Seibt

Neotenic interspecific tolerance leaves Stegodyphus dumicola (females 8.5 mm total body length, 62 mg) defenseless against large hostile congeners (female Stegodyphus africanus 15.0 mm, 383 mg)

Literature
Seibt, Uta, Wickler, Ilse & Wickler, Wolfgang 1998: Dispersal in the solitary Stegodyphus africanus and heterospecific grouping with the social Stegodyphus dumicola (Araneae, Eresidae).Journal of Arachnology 26, 97-100

Wickler, Wolfgang & Seibt, Uta 1988: Two species of Stegodyphus spiders as solitary parasites in social S.dumicola colonies (Araneida, Eresidae). Verhandlungen des naturwissenschaftlichen Vereins Hamburg (NF) 30, 311-317.