Diversity and distribution patterns of some mesophyll‐feeding leaf hoppers of temperate woodland canopy

Temperate woodland canopy as a habitat for insects is discussed. A general account is given of the Typhlocybinae as the mesophyll‐feeding guild of canopy feeders. Three sampling sites in South Wales are described, from which adult leaf‐hoppers were sampled regularly from twelve species of trees during 1974. Rearing records, based on the sampling of last instar nymphs and subsequent rearing of adults, are given. Over 20 000 adult insects of thirty‐five identified species were taken during 1974. Results are analysed to compare species associations with different tree species. Most leaf‐hoppers show very distinct specific plant‐dependent distributions within the canopy. Many are dominantly associated with only one host plant. Others show more complicated patterns of associations. Only one species was found on all trees sampled. The patterns of leafhopper distributions in woodland canopy are compared with previously described grassland habitats. The relative permanence and size of trees may be important factors. Examples of groups of ecologically similar species coexisting together are discussed.