Key to species of the annulignatha- group in China (based on male genitalia)

1 Valva arched or sinuate on ventral margin................................................................. 2

- Valva triangularly projected on ventral margin.............................................................. 3

2 Valva arched on ventral margin, gnathos banded anteromedially, costa with an apical spine (Fig. 45).. M. sinuicosta sp. nov.

- Valva sinuate on ventral margin, gnathos elliptical anteromedially, costa without an apical spine (Fig. 44)................................................................................................... M. artivalva sp. nov.

3 Costa with a sub-quadrate process near base, sacculus with a digitate process dorsoapically (Fig. 43).................................................................................................... M. annulignatha sp. nov.

- Costa with a banded process near base, sacculus with a narrow triangular or a sub-rounded process dorsoapically......... 4

4 Sacculus with a sub-rounded dorsoapical process, aedeagus without spines at apex (Wang 2006a: Fig. 8)..... M. bifoliolata

- Sacculus with a narrow triangular dorsoapical process, aedeagus with spines at apex (Fig. 46)...... M. taiwanensis sp. nov.