Mouthpart palp sensilla of basal Trichoptera families

A comparative SEM study of palp sensory surfaces in 25 caddisfly species representing seven families reveals types sensilla: long trichoid, blunt chaetoid, campaniform, mushroom-like pseudoplacoid, petaloid, thick basiconic and thin sensilla. Long trichoid chaetoid sensilla are present on all segments both pairs palps. First second maxillary palps bear groups sclerotised their medial surface. Other labial have shorter thinner mainly ventromedial surfaces. Campaniform usually occur the first segment Mushroom-like pseudoplacoid may occupy or only distal ones. Petaloid form fields apical most studied species. Thick complexes tips comparison with Lepidoptera suggests similarity conservative evolution The reconstructed ground plan for Trichoptera Amphiesmenoptera is provided.