Key to species of Macrotrichia gen. n. (males)

1. Aedeagus with single process arising from dorsal apodeme; a bifurcate subapical process of style along inner margin ................................................................................................................... M. flavomarginata (Kuoh & Cai) n. comb.

- Aedeagus with paired processes arising from dorsal apodeme; an unforked subapical process of style along inner margin ........................................................................................................................................................................... 2

2. Subapical process of style triangular, directed somewhat posteriorly; aedeagal shaft long and curved dorsally, tapering gradually in lateral view (Figs. 15, 16) ........................................................................................... M. deltata sp. n.

- Subapical process of style hook-like, directed anteriorly; aedeagal shaft short and straight, apex abruptly sharp in lateral view (Figs. 21, 22) ................................................................................................................... M. hamata sp. n.