part of overlaps develops from leg joint mesothoracic leg mesothoracic coxa mesothoracic trochanter mesothoracic coxa-trochanter joint distal joint of mesothoracic coxa The joint between the distal end of the mesothoracic coxa and the proximal end of the trochanter. The fossa (socket) of this joint is part of the coxa. The condyle (ball) is part of trochanter. proximal joint of mesothoracic trochanter JTr FBbt:00007663 fly_anatomy.ontology coxa-trochanter joint presumptive mesothoracic coxa-trochanter joint