Helochares (Hydrobaticus) nipponicus Hebauer, 1995

Dong, Xue & Bian, Dongju, 2021, Three new species and two new records of Helochares (Hydrobaticus) MacLeay 1871 from China (Coleoptera: Hydrophilidae: Acidocerinae), Zootaxa 4950 (1), pp. 166-180 : 175

Helochares (Hydrobaticus) nipponicus Hebauer, 1995

( Figs. 15–16 , 22 )

Helochares striatus Sharp, 1873: 60 .

Helochares (Hydrobaticus) nipponicus Hebauer, 1995: 6 .

Material examined: 7 exs. (IAECAS): Jilin Province, Baishan City, Baoquanshan Town, Bapandao Village , 2017.07.02, 41°29’35”N, 127°34’7”E, 962 m, leg. Peng.

Diagnosis. Habitus as in Figs. 15–16 . BL: 4.8–5.0 mm, BW: 2.5–2.8 mm. Body oval, moderately convex. Head and pronotum dark brown, elytra, ventral side and apex of tarsal claws black. Clypeus dark brown, broad; anterior margin broadly emarginate; frontoclypeal suture distinct; a pair of splayed black marks on frons. Pronotum with a dark mark near anterior margin medially. Elytra widest at midpoint, then slightly attenuated posteriorly. Strial punctures distinctly recognized, and interstrial punctures dense which smaller than the strial punctures.

Aedeagus ( Fig. 22 ) 1.0 mm long, strongly narrowed in distal 1/3. Basal piece short, about 0.3-times of aedeagus length. Parameres with long spines crossing or nearly crossing at apex ( Fig. 22a ). Median lobe broadly membranous, accompanied with a medial sea anemone-like structure ( Fig. 22b ).

Distribution. China: Jilin (new record species to China); Japan; South Korea.

Figures

FIGURES 13–16. Habitus. 13, 14. Helochares (Hydrobaticus) minor; 15, 16. Helochares (Hydrobaticus) nipponicus. 13, 15. Dorsal view; 14, 16. Ventral view.

FIGURES 21–24. Aedeagus (ventral view). 21. Helochares (Hydrobaticus) minor (a. Sea anemone-like structure in membranous inner sac; b. Dentiform bulges); 22. Helochares (Hydrobaticus) nipponicus (a. Parameres; b. Sea anemone-like structure in membranous inner sac); 23. Helochares (Hydrobaticus) lentus (a. Lateral margins of median lobe; b. Long spines; c. Parameres); 24. Helochares (Hydrobaticus) neglectus (a. membranous inner sac).