Key to Chalcovietnamicus species groups and species

1. Embolus screw-like, without large embolic disc (ED) hidden between palpal bulb and cymbium; retromargin of chelicerae with one large fissidentate tooth of four cusps (Logunov 2020: figs 5–6)......................................... C. naga

- Embolus not screw-like, with large embolic disc (ED) hidden between palpal bulb and cymbium; retromargin of chelicerae with one bicuspid tooth (Figs 141–146)................................................... 2 ( Chalcovietnamicus s. s.)

2. Body with three conspicuous golden setal bands on carapace and dorsal abdomen (Figs 105–109; 118–125); a large apical flag-like embolic apophysis (EA) present on the dorsal side of embolus (Figs 116–117, 133–134)....... 3 (vietnamensis- group)

- Body covered with dense khaki setae (Figs 1–11, 29–30, 41–48, 70–76, 88–94); dorsal side of embolus lacking large apical flag-like embolic apophysis (EA; Figs 60–65).................................................. 4 ( daiqini -group)

3. Males with golden setal bands on lateral sides of dorsal carapace (Wang & Li 2022: fig. 4C); embolus without distal retro-ventral keel (dk; Fig. 117); in females, accessory glands (AG) visible in dorsal view of vulva (Fig. 115).............. C. lii

- Males have no golden setal bands of scale setae on lateral sides of dorsal carapace (Figs 120, 124), embolus with distal retro-ventral keel (dk; Fig. 133); in females, accessory glands (AG) invisible in dorsal view of vulva (Fig. 136)... C. vietnamensis

4. Median part of embolus bent near 90° in ventral view (Figs 97, 101); median septum of epigynum obviously raised (Fig. 99); distance between spermathecae longer than diameter of each spermatheca (Figs 100, 104)............ C. weihangi sp. nov.

- Median part of embolus not bent near 90° in ventral view (Figs 141–146); median septum of epigynum not raised (Figs 17, 35, 54, 82); distance between spermathecae shorter or equal to diameter of each spermatheca (Figs 17, 36, 55, 83)........... 5

5. Embolus S-shaped in ventral view (Fig. 80); copulatory ducts (CD) shorter than diameter of spermathecae, turning of copulatory ducts very close to spermathecae (Figs 83, 87)............................................... C. terbakar sp. nov.

- Embolus not S-shaped, almost straight or weakly bent in ventral view (Figs 141–146); copulatory ducts not as above...... 6

6. Embolus concave at dorsal side (Figs 66–68); atria small, diameter of atria shorter than 1/3 of diameter of spermathecae (Figs 55, 58)............................................................................... C. marusiki sp. nov.

- Embolus not concave at dorsal side; atria relatively large, diameter longer than 1/3 of diameter of spermathecae.......... 7

7. Apical extension of embolus (aE) obviously backswept (Figs 60–61); copulatory ducts (CD) not obviously bent in ventral view (Fig. 17)..................................................................................... C. daiqini

- Apical extension of embolus (aE) not backswept (Figs 63–65); median part of copulatory ducts (CD) obviously bent (near 90°; Fig. 36) in ventral view................................................................. C. logunovi sp. nov.