Fig. 8

Schematic diagram of the morphogenetic events observed in the midgut symbiotic organ during the development of P. stali. Blue, orange, and gray show host’s intestinal epithelia, symbiotic bacteria, and food flow, respectively. a Newborn first instar nymph. b First instar nymph 1–2 days after hatching. c First instar nymph 2–3 days after hatching. d Second instar nymph on the day of molting. e Second, third and fourth instar nymphs. f Early fifth instar nymph. g Mid fifth instar nymph. h Late fifth instar nymph to adult. For detail, see the main text