In situ hybridization of AfimHDG2. (A) Sagittal section of the Aristolochia fimbriata flower at S6; note expression in the abaxial epidermis of the perianth, and weak expression in its adaxial counterpart. (B–D) Transverse (B) and longitudinal (C, D) sections of the limb at low (B), mid- (C) and high (D) magnification. (E–G) Transverse (E) and longitudinal (F, G) sections of the tube at low (E), mid- (F) and high (G) magnification. (H–J) Transverse (H) and longitudinal (I–J) sections of the utricle at low (H), mid- (I) and high (J) magnification. (K) Transverse section of the leaf. (L–M) Longitudinal section of the floral pedicel (L) and detail of its the hooked trichomes (M). Arrow/bar signs point to detailed expression patterns; ab, abaxial epidermis; ad, adaxial epidermis; fi, fimbriae; g, gynostemium; l, leaf; lb, limb; mv, midvein; ov, ovary; pd, pedicel; t, tube; u, utricle. Scale bars: 100 µm (A, B, E, H); 150 µm (C, F, I); 200 µm (D, G, J); 60 µm (K–M).