Acalitus essigi Hassan 1928

Acalitus essigi (Hassan, 1928)

(Fig. 1)

Type host and locality. Hassan (1928) had not clearly specified the type host or locality but stated that A. essigi was first reported by Essig and Smith (1922) on Himalaya blackberry in California, USA. Keifer (1941) redescribed this species from Rubus vitifolius Cham. & Schlechtendal collected in Sacramento, California, to “definitely characterize the red-berry mite”.

Distribution. Widespread in Europe and the USA and also recorded from Australia, New Zealand, and Chile on many species of Rubus.

Relation to the host. The feeding activity of A. essigi is the causal agent of “red berry disease”, which results in incomplete, uneven ripening of the fruit, and is a particular problem for late maturing varieties (de Lillo & Duso, 1996).

Collection data. England, Norfolk, Norwich, commercial plant nursery site, low numbers of adult females and males on R. fruticosus, 26.viii.2009; England, Kent, Tonbridge, commercial plant nursery site, low numbers of adult females, males and nymphs on R. fruticosus, 07.x.2009 and 12.xi.2009.

Remarks. The first record of eriophyoid mites causing “red berry disease” in England appears to have been made by Massee (1931), who recorded damage from East Malling, Kent, and Kirdford, West Sussex, and listed the host plants as wild and cultivated blackberries, loganberry and Himalaya berry, but did not provide any specific plant names. Massee (1961) confirmed A. essigi from slide mounted specimens and reported it from Rubus spp. from East Malling, Preston, Lancashire and Southfleet, Kent, and reported it as “locally common”.