1	A. Hind femur partly to entirely black	2
–	B. Hind femur entirely yellow to reddish brown	4
2(1)	A. Mesopleuron black below precoxal groove	M. gustavogutierrezi
–	B. Mesopleuron pale yellow to orange-brown below precoxal groove	3
3(2)	A. Face and gena predominantly black	M. geoffbarnardi
–	B. Face and gena predominantly yellow.	M. gregburtoni
4(1)	A. Mesopleuron black below precoxal groove	M. gretchendailyae
–	B. Mesopleuron pale yellow to light brown below precoxal groove.	5
5(4)	A. Propodeum and first metasomal tergum black	M. lucianocapelli
–	B. Propodeum and first metasomal tergum yellowish brown	6
6(5)	A. Hind femur reddish brown.	M. grettelvegae
–	B. Hind femur yellow	M. fredsingeri