Figure 1.

(A) O. smaragdina arolium in the retracted (Top) and the extended phases (Bottom). (B) Sagittal section of a honeybee hind-leg pretarsus. (C and D) Whole mounts of pretarsi in A. mellifera and O. smaragdina, respectively. (E) O. smaragdina, inner view of ventral arolium cuticle. (F) O. smaragdina, dorsal view into opened arolium. (G and H) O. smaragdina, dissected arcus, lateral views. (H) Nonsclerotized arcus arm. (I) A. mellifera, dissected arcus with attached arolium cuticle. ac, arcus; ag, arolium gland; ar, arolium; cl, claw; hc, hemocoel; la, lateral arolium walls; ma, manubrium; pl, planta; up, unguitractor plate; ut, unguitractor tendon; op, opening. [Bars = 100 μm (A–E), 50 μm (F, G, and I), and 20 μm (H).]