Indosialis, Lestage, 1927

Piraonapicha, Kanyakorn, Sangpradub, Narumon, Jaitrong, Weeyawat & Liu, Xingyue, 2020, The alderfly genus Indosialis Lestage, 1927 (Megaloptera: Sialidae) in Thailand and Laos, with a description of a new species, Zootaxa 4786 (2), pp. 233-253 : 252

Key to species of Indosialis based on male (modified from Liu et al. 2008)

1. Head and pronotum orange ( Fig. 2 ); sac-like structure indistinct or absent in genitalia ( Figs. 4 , 15 )..................... 2

- Head and pronotum brown ( Figs. 10 , 11 ); large sac-like structure present in genitalia ( Figs. 13 , 15 )...... I. siamensis sp. nov.

2. Gonocoxite 9 in lateral view robust ( Fig. 4 ); gonostyli 11 straightly directed posteriad, closely spaced with each other ( Liu et al. 2008: fig. 15)...................................................................................... 3

- Gonocoxite 9 in lateral view slender ( Liu et al. 2008: fig. 13); gonostyli 11 slightly curved ventrolaterally, distinctly separated from each other ( Liu et al. 2008: fig. 14)..................................................... I. minora (Banks)

3. Gonocoxite 9 in lateral view with distal one third narrowed ( Fig. 4C )................ I. bannaensis Liu, Yang & Hayashi

- Gonocoxite 9 in lateral view with distal one third inflated ( Liu et al. 2008: fig. 11)............. I. indicus Liu, Flint & Yang

Figures

FIGURE 2. Indosialis bannaensis, lateral view. A. male; B. female. Scale bar: 5.00 mm.

FIGURE 4. Indosialis bannaensis, male genitalia, A. dorsal view; B. ventral view; C. lateral view; D. caudal view. S9: sternum 9; gx9: gonocoxite 9; gst11: gonostylus 11; gx11: fused gonocoxites 11; T9: tergum 9; e: ectoproct. Scale bar: 0.50 mm.

FIGURE 10. Indosialis siamensis sp. nov. (Holotype, THNHM-I-16801), male, A, B. dorsal view; C. lateral view. Scale bars: 5.00 mm.

FIGURE 11. Indosialis siamensis sp. nov. (paratype), female in lateral view. Scale bar: 5.00 mm.

FIGURE 13. Indosialis siamensis sp. nov., male genitalia (paratype), A. dorsal view; B. ventral view; C. lateral view; D. caudal view. Sac.: sac-like structure. Scale bar: 0.20 mm.

FIGURE 15. Indosialis spp. Indosialis siamensis sp. nov. (A, C, E, G); Indosialis bannaensis (B, D, F, H). A, B. dorsal view; C, D. ventral view; E, F. lateral view; G, H. caudal view. Scale bar: 0.20 mm (A, C, E, G); 0.50 mm (B, D, F, H).