Stenothemus, Bourgeois, 1907

Yang, Yuxia, Ge, Shujuan, Yang, Xingke & Liu, Haoyu, 2021, Taxonomic revision of the species of Stenothemus from Southwest China (Coleoptera, Cantharidae), with the descriptions of five new species, European Journal of Taxonomy 757 (1), pp. 1-36 : 32-34

publication ID	https://doi.org/ 10.5852/ejt.2021.757.1409
publication LSID	lsid:zoobank.org:pub:171E0461-2EFC-4E53-8FC3-D902A1AE26DA
DOI	https://doi.org/10.5281/zenodo.5038624
persistent identifier	https://treatment.plazi.org/id/03C7082F-3C54-8F30-FF67-FA1BFADCFD4B
treatment provided by	Felipe
scientific name	Stenothemus
status

Treatment

Key to the species of Stenothemus from Southwest China

1. Pronotum subrounded, with protruding and acute posterior angles ................................................. 2

– Pronotum subquadrate, with nearly rectangular and obtuse posterior angles .................................. 7

2. Elytra yellow, with irregular dark brown markings .......................................................................... 3

– Elytra yellow or brown, without dark markings ............................................................................... 4

3. Aedeagus ( Fig. 2G‒I View Fig ): ventral process of each paramere nearly parallel to dorsal plate in lateral view, laterophyses feebly exceeding middle emargination between dorsal plates; female reproductive system ( Fig. 4C View Fig ): spermathecal duct very long, slightly longer than diverticulum ............................ .................................................................................................................... S. diffusus Wittmer, 1974

– Aedeagus ( Fig. 6A‒C View Fig ): ventral process of each paramere at an obvious angle to dorsal plate in lateral view, laterophyses clearly exceeding middle emargination between dorsal plates; female reproductive system ( Fig. 8A View Fig ): spermathecal duct moderately long, much shorter than diverticulum .............................................................................................. S. grahami Wittmer, 1974

4. Aedeagus: dorsal plate of each paramere acute at apex .................................................................... 5

– Aedeagus: dorsal plate of each paramere rounded at apex ............................................................... 6

5. Body larger, more than 7.5 mm in length; aedeagus ( Švihla 2004: figs 155‒156): apical part of dorsal plate strongly narrowed, middle emargination between dorsal plates very deep, longer than half its length .............................................................................................................. S. jindrai Švihla, 2004

– Body smaller, 6.6 mm in length; aedeagus ( Fig. 10G‒I View Fig ): apical part of dorsal plate slightly narrowed, middle emargination between dorsal plates moderately deep, nearly as long as half its length ........ ...................................................................................... S. jindraimimus Y. Yang & X. Yang sp. nov.

6. Body yellow, pronotum darkened at anterior angles; aedeagus ( Švihla 2004: figs 161‒163): dorsal plates of parameres separated from each other, ventral process of each paramere slightly thickened apically ............................................................................................................. S. benesi Švihla, 2004

– Body brown, pronotum lightened at anterior angles; aedeagus ( Fig. 2A‒C View Fig ): dorsal plates of parameres approaching each other, ventral process of each paramere distinctly thickened apically .................. ............................................................................................... S. shaanxiensis Švihla, 2004 stat. nov.

7. Body uniformly black ( Fig. 1E View Fig ) ..................................................................... S. dundai Švihla, 2004

– Body at least bicolored ..................................................................................................................... 8

8. Pronotum distinctly widened anteriorly; aedeagus ( Fig. 6D‒F View Fig ): dorsal plates of parameres conjoined, with a rounded emargination in middle of apical margin .... S. minutissimus (Pic, 1933) comb. nov.

– Pronotum nearly parallel-sided; aedeagus: dorsal plates of parameres separated ............................ 9

9. Middle antennomeres without smooth impressions in males ......................................................... 10

– Middle antennomeres with smooth impressions in males ...............................................................11

10. Head, pronotum and scutellum testaceous, elytra yellow .... S. singularicollis (Pic, 1933) comb. nov.

– Head and pronotum black brown, scutellum yellow, elytra black ( Fig. 5C View Fig ) .. S. tryznai Švihla, 2004

11. Antennae flattened or thickened, very long, almost reaching apices of elytra in males ................. 12

– Antennae simple filiform, moderately long, at most extending to ¾ length of elytra in males ...... 13

12. Antennomeres IV‒XI flattened; aedeagus ( Fig. 11A‒C View Fig ): ventral process distinctly thickened apically, bent dorsally in lateral view; apex of laterophyses exceeding middle emargination between dorsal plates ..................................................................................... S. laticornis Y. Yang & H. Liu sp. nov.

– Antennomeres IV‒XI cylindrically thickened; aedeagus ( Fig. 10A‒C View Fig ): ventral process slightly narrowed apically, bent ventrally in lateral view; apex of laterophyses not reaching middle emargination between dorsal plates ............................ S. chongqingensis Y. Yang & H. Liu sp. nov.

13. Pronotum yellow, nearly as long as wide; aedeagus ( Fig. 10D‒F View Fig ): lateroapical part of dorsal plate longitudinally ridged; female reproductive system ( Fig. 12C View Fig ): diverticulum and spermatheca extremely long, diverticulum much shorter than spermatheca ........................................................... ................................................................................................. S. flavicollis Y. Yang & S. Ge sp. nov.

– Pronotum reddish brown or black, distinctly longer than wide; aedeagus: dorsal plate not ridged; female reproductive system: diverticulum and spermatheca moderately long, diverticulum much or slightly longer than spermatheca .................................................................................................... 14

14. Aedeagus ( Fig. 2D‒F View Fig ): ventral process of each paramere moderately long, apex of laterophyses not reaching middle emargination between dorsal plates; abdominal sternite VIII ( Fig. 3B View Fig ): lateroapical angles widely rounded, posterior margin roundly emarginate in middle, sclerotized membrane simple, without rectangular longitudinal sclerite ............................. S. davidi ( Pic, 1926) comb. nov.

– Aedeagus ( Fig.6G‒I View Fig ): ventral process of each paramere short, apex of laterophyses clearly exceeding middle emargination between dorsal plates; abdominal sternite VIII ( Fig. 7D View Fig ): lateroapical angles triangular and protruding, posterior margin rectangularly emarginate in middle, sclerotized membrane with a rectangular sclerite present at center and a small longitudinal sclerite on each side ............... ................................................................................................ S. gracilis Y. Yang & X. Yang sp. nov.

Note

Stenothemus kansuensis Pic, 1933 is not included in the key because the type was not located by us.