Key to species of Synochoneura based on the male genital characters

1. Valva long and narrow, distinctly narrowed beyond middle, forming a neck; sacculus very long, exceeding termination of costa ................................................................................................................. S. ochriclivis

- Valva short and broad, without distinctly narrowed neck; sacculus short, not reaching termination of costa......................................................................................................................................................................2

2. Distal part of valva slightly contracted; free termination of sacculus subquadrate; aedeagus slender........... .................................................................................................................................................. S. tapaishani

- Distal part of valva distinctly contracted; free termination of sacculus dentate; aedeagus stout ................... ........................................................................................................................................ S. dentana sp. nov.