mesosternum
From ZooTerms (Dictionary of Invertebrate Zoology)
mesosternum (noun; Greek mesos, middle; sternon, breast): 1. (Arthropoda: Crustacea) In some Decapoda Brachyura, the median plate of the sternum.
2. (Arthropoda: Insecta) In Hymenoptera, the ventral part of the mesothorax; between the fore and mid-coxae.
