The mesosoma's the middle part of the body, or tagma, of arthropods whose body's composed of three parts, the other two being the prosoma and the metasoma. It bears the legs, and, in the case of winged insects, the wings. In Apocrita Hymenoptera (wasps, bees and ants), it consists of the three thoracic segments and the first abdominal segment (the propodeum). For historical reasons, in ants it's commonly referred to by the alternative name alitrunk.(External Link)(External Link)(External Link)… (More on Mesosoma)