Enithares sinica (Stål)

Polhemus, Dan A., 2020, Nine new species of Enithares (Heteroptera: Notonectidae) from New Guinea, with distributional notes on other species and an updated world checklist, Zootaxa 4772 (1), pp. 132-182 : 176

Enithares sinica (Stål)

Enithares sinica (Stål) 1854:241

Material examined. VIETNAM, Ho Chi Minh City: 1 female, pond beside orchid house at Saigon Botanical Garden, 14 m ., 10°47′15′′N, 106°42′25′′E, 20 November 2014, CL 6011, D. A . Polhemus ( BPBM) . Lai Châu Prov.: 3 males, 3 females, Nam Na River and Nam Ceung stream trib., 15.5 km. N. of Lai Châu, 200 m ., 22°08′52′′N, 103°11′33′′E, water temp. 21.5° C. (trib.), 11 April 2000, 10:00–13:00 hrs., CL 4409, D. A . Polhemus, J. T. Polhe- mus and P. Nguyen ( USNM) . Lào Cai Prov.: 4 males, 11 females, crest of pass N. of Mt. Fan Si Pan , 18 km. NW of Sa Pa on Lai Chau road, 1980 m., 22°21′10′′N, 103°45′57′′E, water temp. 16° C., 8 April 2000, 09:00–11:00 hrs., CL 4400, D. A . Polhemus, J. T. Polhemus and P. Nguyen ( USNM) ; 1 male, rocky stream 12 km. NW of Sa Pa on Lai Chau road, 1815 m., 22°22′22′′N, 103°47′35′′E, water temp. 18.5° C., 8 April 2000, 15:30–16:45 hrs., CL 4404, D. A . Polhemus, J. T. Polhemus and P. Nguyen ( USNM) . Quang Ninh Prov.: 16 males, 7 females, waterfall nr. Yen Tú pagoda, 580 m ., 21°09′09′′N, 106°42′58′′E, water temp. 16° C., 26 March 2000, CL 4380, J. T. Polhemus and P. Nguyen ( USNM). Hai Hung Prov .: 16 males, 5 females, Khe La stream, 22 km. N. of Chi Linh, 160 m ., 21°13′32′′N, 106°29′44′′E, water temp. 18° C., 25 March 2000, CL 4375, J. T. Polhemus and P. Nguyen ( USNM)

Discussion. Males of E. sinica may be immediately recognized by the large, sharp tooth on the male hind femur, and the distinctive, tridentate metaxyphus in both sexes. The above records serve to clarify the broad distribution of this species in Vietnam. Enithares sinica appears to occur in a mutually exclusive pattern with other species in the genus, indicating that it may have differing ecological requirements.

Ecological notes. Enithares sinica ranges from Japan south through China to Taiwan, Vietnam, Laos, the Malay Peninsula and the Philippines, but has never been recorded from Thailand or the islands of the Malay Archipelago ( Zettel et al. 2012). Similar to E. ciliata , it is capable of utilizing both natural and man-made water features, and can sometimes be found in urban settings. This is illustrated by a specimen, listed above, taken by the author from an unshaded ornamental pool about 1 m in depth on the landscaped grounds of the Saigon Botanical Garden.