Fig. 3
From: Morphological responses to feeding in ticks (Ixodes ricinus)
Ixodes ricinus, histological micrographs of the cuticle in fasting, semi-engorged and fully engorged condition. a Adult female in fasting condition, transition between scutum and alloscutum. b Adult female, fasting, cuticle of the scutum. c Adult male, cross section through the opisthosoma with cuticle of the dorsal scutum covering the body. d Fasting female, section through the lateral region of the opisthosoma showing dorsal and ventral alloscutum, and cross-sections through midgut diverticula and tracheae. e Semi-engorged female, section through the alloscutum. f Fully engorged female, high power light micrograph of a section through the alloscutum. g Fully-engorged female, section through the cuticle of the alloscutum, epidermis and midgut epithelium. Note two large tracheae squeezed between midgut epithelium and epidermis. Abbreviations: AS, alloscutum; BC, basal cells of midgut diverticula; CF, cuticular folds; CS, cuticula sensillum; DC, digestive cell; EN, endocuticula; EPD, epidermis; EX, exocuticula; LMDG, lumen of midgut diverticulum; M, muscle; PC, procuticle; S, scutum; T, trachea. Arrowheads indicate pore canals. In Figures a-g, scale bar = 50 μm