Wing‐polymorphism in British species of Longitarsus beetles (Chrysomelidae: Alticinae)

. The incidence of wingpolymorphism is investigated in thirty‐seven of the forty‐one species of Longitursus currently on the British list and twenty‐five species are shown to exhibit variation in wing development. These variations are classified into three groups, fully developed, reduced and vestigial, the reduced form being further divided into three sub‐groups. Variation in wing shape between sexes of a species is recorded and illustrated for the first time. Abdominal wing‐folding spicule patches, previously unrecorded in this genus, are described and illustrated by SEM photographs. Previous work on Longitarsus wing‐polymorphism is briefly reviewed and possible correlations with sex, morphology, distribution and host plant affinities assessed. Records and personal observations of flight in Longitursus species are summarized and the relative unimportance of this ability in a saltatorial group discussed. A table is provided setting out the results of the investigation.