mesoplastron
/ˌmɛsə(ʊ)ˈplastr(ə)n/Zoology
noun
A dermal bone present in the plastron of certain turtles (including most extant pelomedusids).
Origin
Late 19th century. From meso- + plastron. Compare mesoplastral, and xiphiplastron, entoplastron, hyoplastron, hypoplastron.