Metrocoris inthanon Chen & Nieser, 1993

A. D., Tran & Polhemus, D. A., 2017, The genus Metrocoris Mayr, 1865 (Gerromorpha: Gerridae) in Vietnam, with descriptions of five new species, Raffles Bulletin of Zoology 65, pp. 109-149 : 128-130

Metrocoris inthanon Chen & Nieser, 1993

( Figs. 18, 19 , 84, 85 , 91–93 )

Metrocoris ciliatus den Boer, 1965: 23–26 , Figs. 36, 40 , 46 (female paratypes from Laos).

Metrocoris inthanon Chen & Nieser, 1993: 57–59 , Figs. 154, 162, 170 (type locality: Doi Inthanon, Chiang Mai, Thailand); Zettel & Chen, 1996: 152, 177 (records from Vietnam).

Material examined. VIETNAM: Phu Tho Prov.: 1 male, 3 females (apt), Xuan Son N’Park, Kim Thuong, Tan Ong stream, site 3, ca. 4 km from Chin Tang waterfall, coll. Tran A.D. et al., 6 June 2013, TAD1336 ( ZMHU) ; 1 male, 1 female (apt), Xuan Son N’Park, Kim Thuong, Tan Ong stream, site 3, ca. 4 km from Chin Tang waterfall, coll. Tran A.D. et al., 28 August 2013, TAD1342 ( ZMHU) . Thanh Hoa Prov.: 1 female (apt), Pu Luong Nature Reserve, Ba Thuoc, Co Lung, Ban Khuyn, Khuyn stream, coll. Pham T.D., 18 March 2013, PL1303 ( ZMHU) . Nghe An Prov.: 1 male, 3 females (apt), Pu Mat N’Park, Khe Kem waterfall & stream, site #1, coll. Ngo Q.H., 20 December 2012, NQH1203 ( ZMHU) ; 1 male (apt), Pu Mat N’Park, Khe Kem stream, site #2, ca. 300 m downstream from waterfall, coll. Ngo Q.H., 20 December 2012, NQH1204 ( ZMHU) ; 1 male, 1 female, Pu Mat N’Park, Khe Kem stream, site #3, coll. Ngo Q.H., 20 December 2012, NQH1205 ( ZMHU) ; 1 male, 1 female (apt), Pu Mat N’Park, Khe Kem stream, site #4, coll. Ngo Q.H., 20 December 2012, NQH1206 ( ZMHU) ; 3 males, 1 female (apt), Pu Mat Nature Reserve, SW. of Con Cuong, Kem waterfall, 400 m asl, vic. 18°58′13″N, 104°48′03″E, water temp. 22°C, 1 April 2000, CL 4385, coll. J.T. Polhemus & P. Nguyen ( USNM, BPBM) ; 4 males, 6 females (apt), Bac stream, nr. Pu Mat Nature Reserve , 200 m asl, vic. 18°59′18″N, 104°50′33″E, water temp. 24°C, 2 April 2000, CL 4388, coll. J.T. Polhemus & P. Nguyen ( USNM, BPBM) . Ha Tinh Prov.: 1 male, 3 females (apt) , 1 female (mpt), Vu Quang N’Park, Song Con, old Sao La station , coll. Tran A.D., 25 April 2003, TAD0307a ( ZRC) . Quang Binh Prov.: 1 male, 2 females (apt), Phong Nha N’Park, Cha Noi, Khe Khai, coll. Hoang Q.K. & Dinh V.K, 5 August 2002, VNQB0201 ( ZRC) ; 1 male (mpt), Phong Nha N’Park, Khe Gat, Cha Noi, coll. Hoang Q.K. & Dinh V.K., 4 April 2003, VNQB0301 ( ZRC) ; 4 males, 2 females (apt), 1 female (mpt), Phong Nha, Cha Noi, Khe Con Khai stream, coll. Tran A.D., 13 July 2004, DY0402 ( ZRC) ; 1 male (apt), Phong Nha, a stream near Forest Ranger station 37, coll. Tran A.D., 15 July 2004, DY0405 ( ZRC) ; 2 males, 3 females (apt), Phong Nha, Chay stream, coll. Tran A.D., 17 July 2004, DY0410 ( ZRC) . Gia Lai Prov.: 15 males, 15 females (apt), 40 km NW. An Khe, Buon Luoi , 14°10′N, 108°30′E, 620–750 m asl, coll. Pacholátko & Dembicky, 28 March–12 April 1995 ( NHMW, ZRC) ; 19 males, 20 females (apt), 3 females (mpt), Tral Stream, 60 km N. of An Khe , 700 m asl, 14°20′28″N, 108°34′49″E, water temp. 23.5°C, 22 March 2001, CL 4309, coll. D.A. Polhemus, J.T. Polhemus & P. Nguyen ( USNM, BPBM) ; 2 females (mpt), small stream 2 km N. of Tram Lap along forest road, 19 June 1996, ROM-961066, 14°26′N, 108°33′E, primary rainforest, 900 m asl, coll. B. Hulbey ( USNM) . Ninh Thuan Prov.: 1 female (apt), Nui Chua N’Park, suoi Lo O, coll. Quang N.V., 26 June 2004, NC-03 ( ZRC) ; 1 female (apt), Nui Chua N’Park, unknown location, coll. Quang N.V., 26 June 2004, NC-15 ( ZRC) .

LAOS: Champasak Prov.: 5 females (apt), Bolavens plateau E. Pakse, 50 km E. Muang Paksong, 700 m asl, coll. Schillhammer (9), 27 May 1996 ( NHMW) . Vientiane Prov.: 2 males, 3 females (apt), Ban Van Heue, ~ 20 km E. of Phou Khao Khouay park HQ, 1039 m asl, vic. 18°17′44″N, 102°53′48″E, 29 March 1966, coll. J.L. Gressit et al. ( BPBM) . THAILAND: Mae Hong Son Prov.: 3 males, 2 females (apt), NW. Thailand, waterfall near Mae Sariang, coll. C.M. Yang & T.B. Lim, 11 September 1998, YCM219 ( ZRC) .

Diagnosis. Dorsum with extensive dark markings. Both male and female with dense black setae on all thoracic pleura. Male: fore femur slender, not modified ( Fig. 84 ). Male genitalia moderate in size: tergum 8 with median notch on posterior margin; pygophore sub-ovate; proctiger elongate; paramere curved with distal part slightly broad and apex blunt ( Figs. 91–93 ); endosoma as in Chen & Nieser (1993: 170). Female: sternum 7 large, not constricted laterally, posterior margin slightly produced ( Fig. 85 ).

Figures

Figs. 18–31. Dorsal colour patterns of Metrocoris species. 18, 19: M. inthanon, specimens from Vietnam, Nghe An Prov., Pu Mat Nature Reserve (CL 4385). 20, 21: M. sicilis, new species, paratypes, from Vietnam, Hanoi, Ba Vi N’Park (CL 4393). 22, 23: M. triangulatus, specimens from Vietnam, Kontum Prov., 60 km NW. of Kontum (CL 4280). 24, 25: M. nigriventris, new species, paratypes, from Vietnam, Lai Chau Prov., 12 km N. of Lai Chau (CL 4410). 26, 27: M. monticola, new species, paratypes, from Vietnam, Lao Cai Prov., Sa Pa, Sin Chai (TAD1363). 28, 29: M. sapa, new species, paratypes, from Vietnam, Lao Cai Prov., Sa Pa, Nui Xe (TAD0416). 30, 31: M. tenuicornis, specimens from Vietnam, Gia Lai Prov., 60 km N. of An Khe (CL 4309).

Figs. 80–90. Morphological features of Metrocoris species. 80–83: M. ciliatus, macropterous male. 80: right fore leg. 81, 82: left paramere, two different views. 83: endosomal sclerites, lateral view. 84, 85: M. inthanon. 84: right fore leg of male. 85: apex of abdomen, female, ventral view. 86–90: M. triangulatus. 86–89: male holotype. 86: A, right fore leg. 87: left paramere. 88, 89: endosomal sclerites, lateral and dorsal views. 90: abdomen of female, ventral view (80, 84, 86 same scale; 81–83 same scale; 85, 90 same scale).

Figs. 91–93.Metrocoris inthanon, variations of male parameres. 91: specimen from Vietnam, Nghe An Prov., Pu Mat Nature Reserve (CL 4388). 92: specimen from Laos, Vientiane Prov., Ban Van Heue. 93: specimen from Vietnam, Gia Lai Prov., 60 km N. of An Khe (CL 4309).

Figs. 32–43. Parameres of Metrocoris species. 32: M. stranguloides, specimen from Vietnam, Gia Lai Prov., 60 km N. of An Khe (CL 4309). 33: M. bilobatoides, specimen from Vietnam, Lao Cai Prov., 12 km NW. of Sa Pa (CL 4404). 34: M. johnpolhemi, new species, specimen from Vietnam, Lai Chau Prov., Nam Ceung stream (CL 4409). 35: M. quynhi, specimen from Vietnam, Lao Cai Prov., 18 km NW. of Sa Pa (CL 4400). 36: M. obscurus, specimen from Vietnam, Lao Cai Prov., 4 km NE. of Sa Pa (CL 4407). 37: M. acutus, specimen from Vietnam, Hai Hung Prov., 22 km N. of Chi Linh (CL 4375). 38: M. nigrofascioides, specimen from Vietnam, Binh Dinh Prov., An Khe Pass (CL 4291). 39: M. sicilis, new species, specimen from Vietnam, Hanoi, Ba Vi N’Park (CL 4393). 40: M. triangulatus, specimen from Vietnam, Gia Lai Prov., N. of Tram Lap (ROM-961066). 41: M. ciliatus, paratype, from Vietnam, Lai Chau Prov., Muong Te (TAD1329). 42: M. nigriventris, new species, paratype, from Vietnam, Lao Cai Prov., 20 km NE. of Sa Pa (CL 4406). 43: M. monticola, new species, paratype, from Vietnam, Lao Cai Prov., Sa Pa, Sin Chai (TAD1363).

Figs. 44–55. Morphological features of Metrocoris species. 44–46: M. stranguloides. 44, 45: right fore legs of male. 46: sternum 7 of female, ventral view. 47–51: M. bilobatoides. 47, 48: right fore leg of male, same scale. 49, 50: tergum 7 of female, dorsal view (49: specimen from Tam Dao; 50: specimen from Lao Cai). 51: sternum 7 of female, ventral view. 52–55: M. vietnamensis (52–55 reproduced and modified from Tran & Zettel, 2005). 52, 53: right fore legs of male. 54: left paramere. 55: sternum 7 of female, in situ (44, 45, 47, 48, 52, 53 same scale; 46, 49–51, 55 same scale).