Key to the species of Pterophoridae from Hong Kong

1 Wings uncleft .................................................................................................. Ochyrotica yanoi Arenberger

- Wings cleft...................................................................................................................................................2

2 Third lobe of hindwing with one vein ........................................................................................................ 3

- Third lobe of hindwing with two veins......................................................................................................11

3 Forewing cleft near base or at middle......................................................................................................... 4

- Forewing cleft at distal part.........................................................................................................................5

4 Valvae asymmetrical........................................................................................ Diacrotricha fasciola Zeller

- Valvae symmetrical ........................................................................... Sphenarches anisodactylus (Walker)

5 Forewing with distinct terminal margin and anal angle in both lobes........................................................ 6

- Forewing without terminal margin and anal angle in first lobe .......................... Exelastis pumilio (Zeller)

6 Valva bifid or “bird-headed” in shape distally.............................................................................................7

- Valva simple, rounded distally ......................................... Platyptilia calodactyla (Denis & Schiffermüller)

7 Valva bifid distally......................................................................................................................................8

- Valva somewhat “bird-headed” in shape distally ....................................................................................... 9

8 Valva between sacculus and cucullus deeply indented........................................... Nippoptilia minor Hori

- Valva between sacculus and cucullus not indented .............................................. Nippoptilia vitis (Sasaki)

9 Valva with a large overriding cucullus ....................................................... Asiaephorus sythoffi (Snellen)

- Valva without overriding cucullus.............................................................................................................10

10 Saccus elongate, forked apically ...................................................... Lantanophaga pusillidactyla (Walker)

- Saccus subtriangular, acute apically .............................. Stenoptilodes taprobanes (Felder & Rogenhofer)

11 Forewing cleft at near 2/3, lobes relatively wide.......................................................................................12

- Forewing cleft at middle or before, lobes slender.....................................................................................14

12 R4 stalked with R3 or R 5 in forewing ............................................................ Adaina microdactyla (Hübner)

- R2 - R5 free in forewing..............................................................................................................................13

13 Right sacculus with sclerotized finger-shaped process at apex .................. Hellinsia sichuana Arenberger

- Right sacculus fused with valva at apex, without finger-shaped process ........ Hellinsia lienigiana (Zeller)

14 Left sacculus with stout spiny process ....................................................... Pterophorus attenuatus sp. nov.

- Left sacculus with relatively slender process...........................................................................................15

15 Sacculus with nearly “S-shaped” process, anellus with arm from middle .................................................... ......................................................................................................... Pterophorus pentadactylus (Linnaeus)

- Sacculus with semicircular process, anellus with arm from distal 2/3 ............ Pterophorus maolanensis Li