Type material of the species of Alloxysta described by Cameron and Fergusson and deposited in the Natural History Museum of London has been revised. Seven species are considered valid: Alloxysta abdera Fergusson, 1986, A. basimacula (Cameron, 1886), A. crassa (Cameron, 1889), A. mullensis (Cameron, 1883), A. piceomaculata (Cameron, 1883), A. pleuralis (Cameron, 1879) and A. semiaperta Fergusson, 1986. A. basimacula, A. crassa, A. maculicollis (Cameron, 1886), A. perplexa (Cameron, 1889) and A. piceomaculata are here removed from synonymy with A. macrophadna (Hartig,1841). A. ruficeps (Cameron, 1883) is removed from synonymy with A. victrix (Westwood, 1833). A. caledonica (Cameron, 1886) and A. perplexa are here synonymized with A. basimacula. A. maculicollis, A. ruficeps and A. ruficollis (Cameron, 1883) are here synonymized with A. castanea (Hartig, 1841). A. ancylocera (Cameron, 1886) was correctly synonymized with A. fuscicornis (Hartig, 1841), A. curvicornis (Cameron, 1883) was correctly synonymized with A. victrix and A. filicornis (Cameron, 1889) was correctly synonymized with A. macrophadna. Complete redescriptions and illustrations are given for valid species. A key for all the Alloxysta species found so far in Great Britain is given.
Figitidae, Charipinae, Alloxysta, Cameron, Fergusson.