Mesopleura: in Diptera, the space before the root of the wing between the dorso- and sternopleural sutures: in Hymenoptera, the piece below the insertion of the wings.
Mesopleural bristles: in Diptera, are inserted in the angle formed by the dorso-pleural and meso-pleural sutures.
Mesopleural suture: in Diptera, runs from the root of the wings downward and separates the meso-pleura from the pteropleura.
Mesopleuron: the lateral surface of the meta-thorax.
Mesosternal cavity: in Elateridae, the opening into which the prosternal spine or mucro is fitted.
Mesosternal epimera: in Coleoptera; the narrow pieces separating the meta-sternal from the meta-sternal episterna.
Mesosternal episterna: Coleoptera; on each side of mesosternum between anterior border and epimera; generally separated by a distinct suture.
Mesosternal lobes: in Orthoptera; = mesosternellum, q.v.
Mesosternellum: in Orthoptera, two median lobes of the mesosternum, one on each side of the deep median notch: in general, the sternellum of the mesothorax.
Mesosternum: the underside or breast of the meta-thorax.