Key to Oriental and Palearctic genera of Deltocephalini (males)

1. Posterior margin of pygofer lobe pectinate................................................... Ctenurella Vilbaste

- Posterior margin of pygofer lobe entire, unmodified........................................................... 2

2. Pygofer lobe with elongate dorsal process arising near base and extended distad................... Paramesodes Ishihara

- Pygofer lobe without elongate dorsal process (one or more small teeth or internal sclerotized ridges may be present)........ 3

3. Aedeagal shaft very elongate, more than 1 ½ times length of connective, without preapical processes.................... 4

- Aedeagal shaft short to moderately long, less than 1 ½ times length of connective, with or without preapical processes...... 6

4. Subgenital plate and pygofer very long............................................... Wyushinamia Zhang & Duan

- Subgenital plate and pygofer not elongated.................................................................. 5

5. Forewing with numerous extra crossveins in corium and clavus, apex of aedeagus entire................ Polyamia DeLong

- Forewing with, at most, 1–2 extra crossveins; apex of aedeagus bifid......................... Yuanamia Zhang & Duan

6. Aedeagal shaft with paired processes....................................................................... 7

- Aedeagal shaft without paired processes (apex may be bifid)................................................... 10

7. Aedeagal processes arising basad of gonopore............................................................... 8

- Aedeagal processes arising laterad or distad of gonopore....................................................... 9

8. Aedeagal processes short, toothlike, apex of shaft extended well beyond gonopore................... Peitouellus Vilbaste

- Aedeagal processes long, spinelike, apex of shaft terminating at gonopore......................... Alobaldia Emeljanov

9. Aedeagal processes serrate............................................................. Maiestas Distant (part)

- Aedeagal processes entire................................................... Miradeltaphus Dash & Viraktamath

10. Aedeagal shaft strongly compressed over distal two-thirds, apex with ventral asymmetrical spine.... Matsumuratettix Metcalf

- Aedeagal shaft tubular, symmetrical, without distal spine...................................................... 11

11. Forewing usually with extra crossveins in clavus; aedeagal shaft with median apical notch in ventral view...... Endria Oman

- Forewing without extra crossveins in clavus; aedeagal shaft apex without median notch in ventral view................................................................................................... (Deltocephalus group) 12

12. Aedeagal shaft with apex in lateral view bluntly rounded................................... Deltocephalus Burmeister

- Aedeagal shaft with apex in lateral view terminating in sharp point.............................................. 13

13. Aedeagal shaft with slender ventroapical spine much narrower than shaft in lateral view.................. Recilia Edwards

- Aedeagal shaft slender and tapered throughout length in lateral view, without ventral spine narrower than shaft............................................................................................... Maiestas Distant (part)