Distribution of palp sensory surface characters within Trichoptera. A. Localization of sensory fields on maxillary palp segments: on the fifth segment (blue), on the third and fourth segments (green), total reduction of sensory fields (red); B. Degree of development of apical sensory complex on the palps: on both pairs of palps (blue), only on maxillary palps (green), only on labial palps (yellow), total reduction of apical sensory complexes on both pairs of palps (red). The phylogenetic tree is based on the data from Holzenthal et al. 2007a.