FIGURE 2 in Structure and phylogenetic significance of the sternum V glands in Trichoptera 2884

FIGURE 2. Drawings based on wholemounts. The structures are viewed through the cuticle, anterior is to the left with down being mesal; thus all drawings show the left gland. Muscle fibres are grey and all structures are drawn as if they were transparent. Transparency of cuticle is not indicated. A: Stenopsychodes mjoebergi female (Stenopsychidae), Trichoptera-type opening muscle originating mesally on cuticle of sternum V and inserting on the gland duct wall just inside gland opening. The secretory tissue was not discernible, possibly due to decomposition. The muscle fibres around the reservoir are found only on the side towards the cuticle. B–E: Philopotamidae, note scaly patches around gland opening. B and C: Wormaldia arizonensis female and male, respectively, note the presence of both Lepidoptera-type and Trichoptera-type opening muscles. D and E: W. planae female and male, respectively, only Lepidoptera-type opening muscle present. Go, gland opening; Ip, insertion point for muscle; Op, origin point for muscle; Rs, gland reservoir; Sc, secretory cells; T-t, Trichoptera-type opening muscle; L-t, Lepidoptera-type opening muscle.