Eugoa, Walker, 1858

Bayarsaikhan, Ulziijargal, Bucsek, Karol & Bae, Yang-Seop, 2018, A review of the genus Eugoa Walker (Lepidoptera, Erebidae, Arctiinae, Lithosiini) in Cambodia, with the description of a new species, Zootaxa 4403 (3), pp. 469-494 : 470-471

Key to the species of the genus Eugoa from Cambodia based on male genitalia

1 Tegumen shouldered................................................................................... 2

- Tegumen not shouldered................................................................................ 5

2 Valvae elongate, with rounded apex....................................................................... 3

- Valvae stout, with irregularly shaped apex.................................................................. 4

3 Uncus subtrapezoidal; inner surface of tegumen densely spinous; cornuti absent........................... E. gabrielae

- Uncus not subtrapezoidal; tegumen sparsely spinous internally; aedeagus with small apical spines and two sclerotized plates in vesica................................................................................... E. arguta n. sp.

4 Uncus almost 90ångled; tegumen with slender, finger-shaped apical branches; apex of valvae rectangular, with claw-shaped ampulla in 1/3; aedeagus with a bundle of short spines apically and an irregular cornutus in vesica......... E. obliquipuncta

- Uncus not 90ångled; tegumen with membranous, arch-shaped apical branches; apex of valvae finger-shaped, with leaf-shaped ampulla in basal area; aedeagus with a spine-shaped cornutus............................................. E. latera

5 Apical process of sacculus present....................................................................... 6

- Apical process of sacculus absent......................................................................... 8

6 Saccular process bifurcated; juxta distinct................................................................. 7

- Saccular process not furcated; juxta indistinct.......................................................... E. nata

7 Saccular process asymmetrically bifurcated; apex of valvae rounded; juxta X-shaped; aedeagus with an irregular cornutus.......................................................................................... E. vasta n. comb.

- Saccular process symmetrically bifurcated; apex of valvae rectangular; juxta triangular; aedeagus with several spine-shaped cornuti..................................................................................... E. bidentata

8 Valvae with digitate ampullae........................................................................... 9

- Valvae without digitate ampullae........................................................................ 10

9 Ampullae slender, covered with setae whole of length.................................................. E. khmera

- Ampullae robust, inner surface setose............................................................ E. malayicola

10 Valvae symmetrical................................................................................... 12

- Valvae asymmetrical.................................................................................. 11

11 Apex of valvae rounded; sacculus robus; juxta with two vertical, band-shaped plates; aedeagus sclerotized distal half.................................................................................................. E. tineoides

- Apex of valvae angled; sacculus slender; juxta with two arch-shaped plates; aedeagus sclerotized whole of length.................................................................................................... E. unicolora

12 Saccus weakly developed or absent...................................................................... 13

- Saccus well developed................................................................................ 17

13 Costal margin of valvae with a large medial spine-shaped process; saccus absent.................... E. formosicola n. st.

- Costal margin of valvae lacking a medial; saccus weakly developed............................................. 14

14 Apex of valvae rectangular............................................................................. 15

- Apex of valvae not rectangular.......................................................................... 16

15 Uncus slender, half the length of tegumen; apex of valvae sub-rectangular, not dentate apically; costal margin of valvae curved subapically, without hook-shaped subapical process.................................................... E. cernyi

- Uncus stout, with almost the same length of tegumen; apex of valvae rectangular, weakly dentate apically; costal margin of valvae curved medially, with hook-shaped subapical process......................................... E. kuznetzovi

16 Valvae robust, tapering, weakly angled apex, lacking spines........................................... E. tessellata

- Valvae slender, elliptical-shaped apex with two asymmetrical spines..................................... E. mangle

17 Valvae robust, with a large, conic process at middle of costal margin; saccus rounded, with almost half the length of tegumen............................................................................................. E. muluana

- Valvae slender, without a medial process; saccus not rounded................................................. 18

18 Saccus wineglass-shaped; apex of valvae rounded; aedeagus without cornutus....................... E. aliquotpunctata

- Saccus not wineglass-shaped; apex of valvae not rounded; aedeagus with cornutus................................. 19

19 Valvae tapering with acute apex; saccus boat-shaped; aedeagus with a slender spine........................ E. bipuncta

- Valvae elongate with weakly dentate apex; saccus rectangular; aedeagus with a bundle of short spines............ E. lucea