Skeletomuscular differences in the thorax of winged and non-winged forms of Camponotus camelinus (Smith) (Hym., Formicidae)

Comparative study of the thorax between the non-winged and winged forms of the ant Camponotus camelinus Smith brings to light some interesting skeletomuscular differences. In the winged form, the pro-, the meso-, and the metathoracic components of the thorax are loosely associated, while the pronotum is reduced. The mesoalinotum and mesopectus are differentiated into sclerites by sutures and ridges as in other winged Hymenoptera, but absent in the non-winged form. The metanotum is demarcated from the mesonotum, the propodeum and the metapectus. The metapectus follows the same pattern as does the mesopectus. The first and second phragmata are present. The meso- and meta-endosternites are stout and connected to each other by intersegmental muscles. The different wing sclerites and processes are differentiated from the surrounding components of the thorax. The muscle controlling the wing movements are well developed. Some other muscles which are present in the non-winged form are either displaced or are absent in the winged form.