Key to males of Thaia from China

1 Anal tube without apical process Thaia (Thaia) ........................................................................................................... 2

– Anal tube with apical process extending ventrally from 10th segment Thaia (Nlunga) ............................................. 7

2 Aedeagal shaft with one or more basal processes......................................................................................................... 3

– Aedeagal shaft without processes ................................................................................................................................. 5

3 Base of aedeagus with single long, fingerlike process ......................................................................... T . (Thaia) nigra

– Base of aedeagus with pair of processes....................................................................................................................... 4

4 Dorsal apodeme of aedeagus expanded, approximately scissorlike ............................................... T . (Thaia) oryzivora

– Dorsal apodeme of aedeagus small, approximately trapezoidal ....................................................... T . (Thaia) subrufa

5 Dorsal apodeme of aedeagus with pair of small, toothlike processes .......................................... T . (Thaia) formosana

– Dorsal apodeme of aedeagus without toothlike processes............................................................................................ 6

6 Aedeagal shaft long and slim, tubelike, without serrations .......................................................... T . (Thaia) longipenia

– Aedeagal shaft short, lamellate, with ventral serrate comb .............................................................. T . (Thaia) barbata

7 Apical process of anal tube bifurcate at apex ................................................................................. T . (Nlunga) sinuata

– Apical process of anal tube not bifurcate at apex ........................................................................................................ 8

8 Ventral appendage of pygofer with few small, serrations both at base and apex ......................... T. (Nlunga) anchora

– Ventral appendage of pygofer without serrations ......................................................................................................... 9

9 Aedeagus with two pairs of processes (Figs 7, 8) ....................................................... T. (Nlunga) mengyanga sp. nov.

– Aedeagus without processes .......................................................................................................... T . (Nlunga) maxima