7. Parena taiwana species group

This species group contains only one species endemic in south China. It is characterized by: dorsum yellowish brown; antennae slender, extended beyond elytra base; retinacular ridge of right mandible about two-thirds length of terebral ridge (Fig. 2D); elytra intervals strongly punctate; elytral apices evenly rounded; males with biseriate adhesive setae near the full length of mesotarsomere 1 ventrally; median lobe of aedeagus very slender (AL/AW 5.5–6.0), apical lamella thin; gonocoxite II of ovipositor nearly ovate, apex with six ensiform setae, two on each angle and two near the middle.

This species group is unique in the subgenus for its males with adhesive setae on mesotarsomere 1 and male genitalia very slender. These two genital characters are in accord with some groups of the subgenus Parena . In P. taiwana, the adhesive setae occupy nearly the full length of mesotarsomere 1, whereas in subgenus Parena, the adhesive setae at most occupy slightly more than the apical half of mesotarsomere 1. Based on many other important characters mentioned above, we assigned P. taiwana into the subgenus Bothynoptera and considered that it is not closely related to species of subgenus Parena . Although P. taiwana is very similar to the P. tripunctata group in external features and female ovipositor, we consider P. taiwana to be relatively isolated in the subgenus because of its atypical male genitalia and the pattern of tarsal adhesive setae.