Porrorhynchus (Porrorhynchus) marginatus Laporte, 1835

Gustafson, Grey T. & Miller, Kelly B., 1835, Revision of the Southeast Asian Whirligig Beetle GenusPorrorhynchusLaporte, 1835 (Coleoptera: Gyrinidae: Gyrininae: Dineutini), The Coleopterists Bulletin 1835 (4), pp. 675-714 : 675-714

Porrorhynchus (Porrorhynchus) marginatus Laporte, 1835

( Figs. 1A , 2C , 3A–B , 4 , 8 , 9 , 13C , 14 , 17A, 17D, 17G )

Trigonocheilus rostratus: Dejean 1833: 59 , 67 [nomen nudum, synonymy by Aubé 1838a: 406]

Porrorhynchus marginatus Laporte 1835: 108 [original description]; Aubé 1838a: 406, pl. 46, fig. 4 [redescription and habitus image], 1838b: 759 [redescription], 1840: 170 [redescription]; Hope 1838: 145 [list of type species]; White 1847: 48 [specimen holdings]; Desmarest 1851: 224, fig. 399 [redescription and dorsal habitus]; Lacordaire 1854: 440 [minor description]; Wood 1874: 69, fig. 28 [redescription, illustration]; Hagen 1890: 228 [checklist]; Duncan 1891: 311 [minor description]; Laporte 1910: 170 [redescription]; Balke et al. 2004: 570, Fig. 5A [distribution, dorsal habitus]; Jäch et al. 2012: 66 [distribution]. Miller and Bergsten 2012: figs. 9D, 12B, 15D, 16A, 20B [morphology].

Porrhorhynchus tenuirostris Régimbart 1877a: 21 [description], 1877b: 111, fig. 4 [redescription, dorsal habitus].

Porrhorhynchus marginatus: Régimbart 1877b: 110 , Pl. 6 fig. 3 [revision, elytron], 1882: 427, pl. 12, fig. 49, fig. 49a [redescription, range extension, elytron, foreleg], 1884: 270 [checklist], 1892a: 740 [checklist], Régimbart 1902: 5 [distribution], 1907: 152 [distribution].

Porrhorhynchus marginatus var. tenuirostris: Régimbart 1882: 428 [new status, redescription], 1884: 470 [checklist], 1892a: 740 [checklist].

Porrhorrhynchus marginatus: Zimmermann 1917: 139 [locality and holdings information]; Peschet 1923: 122 [review]; Hatch 1926b: 450 [minor description].

Dineutus (Porrorhynchus) marginatus: Ochs 1926: 139 [new status, checklist], 1927b: 242 [distribution, habitat note], 1927a: 116 [distribution], 1928: 44 [distribution], 1929a: 248 [distribution], 1930: 16 [catalog], 1931: 472 [distribution], 1937: 111 [locality data], 1940a: 5 [locality data], 1940b: 33 [distribution, habitat, variation], 1953: 220 [locality data]

Dineutus (Porrorhynchus) marginatus tenuirostris: Ochs 1926: 139 [new status, checklist], 1930: 17 [catalog].

Dineutus (Porrorhynchus) marginatus mjöbergi: Ochs 1926: 139 [nomen nudum, checklist], 1926: 193 [original description], 1928: 44 [redescription], 1930: 17 [catalog]. New synonymy.

Porrorhynchus (Porrorhynchus) marginatus: Brinck 1955: 103 [new status].

Type Material Examined. Porrorhynchus marginatus Laporte, 1835 lectotype here designated (1 ♀ card mounted, Fig. 17A ): “ Rostratus / (Java.) [handwritten black ink on card mount base, handwriting unknown]//” (1 ex. MVMA) .

Porrorhynchus tenuirostris Régimbart, 1877 lectotype here designated (1♂ pinned, Fig. 17D ): “MUSEUM PARIS/ COCHINCHINE/ HARMAND 1876 [white label, printed black ink]// yellow disk [underneath is handwritten 9/ 668 in black ink]// 7 [handwritten in black ink on small beige square]// MUSEUM PARIS/ MUSEUM PARIS COLL MAURICE REGIMBART/ 1908 [white label with thin black border, type black ink]// TYPE [red label, black ink]// LECTOTYPE [red label, black ink]//” (1 ex. MNHN) . Paralectotypes (3: 1 ♂ pinned, 2 ♀♀ pinned): Same labels as lectotype except without yellow disk or beige square and with “ PARALECTOTYPE [red label, black type]// ” (3 ex. MNHN) .

Dineutus (Porrorhynchus) marginatus mjobergi Ochs, 1926 lectotype here designated (1 ♂ pinned, with aedeagus on point, Fig. 17G ): “ ♂ [white label, typed black ink]// Mt. Dulit/ 3,500 f. [beige label, typed black ink]// Coll./ G.Ochs [white label, typed black ink]// Cotypus [red label with black borders, typed black ink]// P. marginatus / subsp. mjobergi / Type! Ochs/ 1924 [beige label, handwritten in ink, handwriting

appears to be Ochs’]// mjobergi Ochs [beige label with black border, handwritten in ink, handwriting appears to be Och’ s]// LECTOTYPE [red label, typed black ink]//” (1 ex. SMF). Paralectotype (1 ♀ pinned): Same data as lectotype except ♀ symbol label and without mjobergi Ochs label and with “ PARALECTOTYPE [red label, typed black ink] (1 ex. SMF) .

Type Designations. After much searching, only a single specimen located in the Laporte Foreign Insect Collection of the MVMA could be found and reliably considered part of the syntype series for P. marginatus . Furthermore, this specimen has the name “ rostratus ” on the card ( Fig.17A ), likely being the origin for the eponymous nomen nudum. Again, because Laporte did not indicate how many specimens he examined, we follow Recommendation 73F of ICZN (1999) and do not regard this specimen as the unique holotype, but instead here designate it as the lectotype for P. marginatus .

Régimbart (1877a) mentions having many examples from Cochinchine from Dr. Harmand, with Phu-Quoc in quotes for his description of P. tenuirostris . In the MNHN collection, there are numerous specimens collected by Harmand, however, only four specifically state Cochinchine on the label and as being collected in 1876. There are many more specimens in the Régimbart collection collected by Harmand, but these have Lakhon as the locality and the collection date as 1878. Given that the publication date is 1877, only those aforementioned four specimens are here considered as part of the syntype series. The specimen selected as the lectotype ( Fig. 17D ) is a male specimen already possessing a label that says “TYPE”. While there is a second description of P. tenuirostris given by Régimbart (1887b), it is the same situation as that encountered with P. brevirostris and should be similarly regarded as a redescription, requiring no additional lectotype designation.

The situation encountered with P. landaisi latilimbus applies also to P. marginatus mjobergi . Therefore, a lectotype is here designated.

Additional Material Examined. INDONESIA: " Borneo ": (3 ex. NMPC) , " Borneo ": Coll. Mus. Vindob. (1 ex. NHMW) ; " Borneo / Sunda Isl. " (2 ex. UMRM) , " Borneo ": 1891, leg. Chaper (4 ex. MNHN) ; same as previous except: 1926, leg. E. Mjöberg, (5 ex. MCZ) ; " Bivang Riv. ", 1926, leg. E. Mjöberg (67 ex. MCZ) ; " Riv. Mandar ", 1897, leg. Fr. Buffat, Coll. MAURICE REGIMBART 1908 (1 ex. MNHN) ; same as previous except: 7.xi.1897, Coll. MAURICE REGIMBART 1908 (9 ex. MNHN) ; " Bohac " (1 ex. NMPC) . East Kalimantan: Kac. Pujungan, Kayan-Mentarang Nat. Reserve , 2°52′N 115°49′E, 378m, 20.ii.-4.iii.1993, leg. D.C. Darling, lowland diptero. Forest / WWF station, Lalut Birai / rocky stream (Nggeng), IIS 930003, ROMEnt Spec. No. 1739, 3150 (4 ex. 2 ROME, 2 CNC) ; same as previous except: 6.vi.1993, leg. D.C. Darling & Rosichon U., lowland diptero. Forest / WWF station, Lalut Birai / small stream above Nggeng River , IIS 930330, ROMEnt Spec. No. 3098, 3141 (3 ex. ROME) . West Kalimantan (“ Borneo ”): "Riv. Sambey", near Ngabang ("pres Ngabang "), 1897, leg. J.B. Ledru, ZML. 2010/ 342-344 (3 ex. MZLU) . Java: (1 ex. NMPC) ; Java: Coll. MAURICE REGIMBART 1908 (1 ex. MNHN) ; Java : leg. O. Koechlin (1 ex. NMPC) ; " Jiansberge ", Coll. M. SÉDILLOT (2 ex. MNHN) . " Sumatra ": Coll. MAURICE REGIMBART 1908 (1 ex. MNHN) ; " Sumatra ": " Balighe ", x.90- iii.91, leg. E. Modigliani (8 ex. ZMUC) ; same as previous except: ZML. 2010/ 345,346,347,354 (4 ex. MZLU) ; same as previous except: Coll. MAURICE REGIMBART 1908 (1 ex. MNHN) ; " Sumatra ": " Palembang ", coll. R. Peschet (7 ex. MNHN) ; "Sumatra": "Manna" (likely the Manna River ), 1901, leg. M. Knappert, Coll. Mus. Vindob. (1 ex. NHMW) ; same as previous except 1902, Coll. Mus. Vindob. (1 ex. NHMW) ; " Sumatra ": " Indrapoera ", Coll. MAURICE REGIMBART 1908 (1 ex. MNHN) . North Sumatra: " Ober Langkat ", "Sumatra/ Sunda Isl. ", "ix-x" (2 ex. UMRM) , Bohorok , vi.1975, leg. P. Blum (1 ex. NHMW) ; Nias , "Hili Madjedja", N. Nias, "4 de trim".1895, leg. I.Z. Kannegieter, ZML.2010/ 348-350 (3 ex. MZLU) ; Gunung Leuser Ntl. Prk., Bukit Lavang env., 26.iv.2004, leg. D. Trávníček, Jiří Hájek Collection (2 ex. NMPC) . West Sumatra: "NSG Lemba Harau", 15km NE Payakumbuh (" Payakumbu "), 11.ii.1991, leg. Jäch ,, 12b, (3 ex. NHMW) ; Siberut Island, Salappa vill. Env. , Labuan Bajau , ii.2006, leg. St. Jakl, Jiří Hájek Collection (2 ex. NMPC) ; same as previous except: xii.2005, leg. St. Jakl, Jiří Hájek Collection (2 ex. NMPC) ; Siberut Island, " Toteburu-Bakeuluk , 17. ii.1991, leg. Schödl, 22 (13 ex. NHMW) ; same as previous except: leg. Jäch, 22 (26 ex. NHMW) ; Siberut Island , "Toteburu", "W Muarasiberut", 16. ii.1991, leg. Jäch, 21 (2 ex. NHMW) . LAOS: Champasak: Ban Houei Khong (" Houei Kong "), iii.1965, J.A. Rondon Collection (5 ex. BPBM) ; Muang Paxong, Ban Thongvay, Bolaven plateau, 15°14.398′N 106°31.806′E, 1000-1200m, 7-16. vi.2008, leg. A. Solodovnikov & J. Pedersen, disturbed primary rainforest (2 ex. ZMUC) . Khammouane: Phon Tiou , 11-12.vi.1965, J.A. Rondon Collection (3 ex. BPBM) ; Ban Khoun Nguen env., 18°07′N 104°29′E, 250m, 4-16, 25- 30.xi.2000, leg. E. Jendek & P. Pacholátko (227 ex. NMW) . Luang Namtha: " Nam Youan ", 7km N of Ban Muangsing, 21°14′N 101°8′E, 1.v.1997, leg. W.J. Rainboth & S. Virawong (2 ex. UMMZ) ; 10-20km NW Luang Namtha, 600m, 17.vi.1996, leg. Schillhammer, 29, (2 ex. NHMW) . Luang Prabang: "A THENG", 1888, leg. A. Pavie (12 ex. MNHN) ; Houay Houp (" Houay Houn "), ca. 16km upstream from mouth at Nam Ou , 3.iii.1998, leg. W.J. Rainboth & K.P. Bounkhamvongsa (2 ex. UMMZ) . Sainyabuli (" Sayaboury "): 18. viii.1966, leg. "Native Collector" (1 ex. BPBM) ; Sainyabuli (" Sayaboury "), 29.iii.1966, leg. "Native Collector" (5 ex. BPBM) ; same as previous except: 20.v.1966 (3 ex. BPBM) . Vientiane: "Ban Van Eue", 15.vii.1965, leg. "Native Collector" (2 ex. BPBM) ; same as previous except: 1-15.ix.1965 (2 ex. BPBM) ; same as previous except: 30. ix.1965 (7 ex. BPBM) ; same as previous except: 30.xi.1965 (5 ex. BPBM) ; same as previous except: 30.i.1966 (1 ex. BPBM) ; same as previous except: 15.ii.1966 (1 ex. BPBM) ; same as previous except: 16.iii.1966 (2 ex. BPBM) ; same as previous except: 15.v.1966 (1 ex. BPBM) ; same as previous except: 31.v.1966 (22 ex. BPBM) ; same as previous except: 30.xi.1966 (1 ex. BPBM) ; same as previous except: 15.xii.1966 (2 ex. BPBM) ; same as previous except: 30.iii.1967 (1 ex. BPBM) ; same as previous except: 30. viii.1967 (1 ex. BPBM) ; same as previous except: 1-15.ix.1967 (1 ex. BPBM) ; Phou Khao Khouay (" Phou Kou Khouei "), 15.ii.1966, leg. "Native Collector" (8 ex. BPBM) ; same as previous except: 15.iv.1966, leg. (3 ex. BPBM) ; Phou Khao Khouay , 18°20.369′N 102°48.523′E, 700- 800m, 26-31.v.2008, leg. A. Solodovnikov & J. Pedersen, strongly disturbed primary rainforest (1 ex. ZMUC) ; Phou Khao Khouay Ntl. Pr. env., Tad Luek Waterfall , 200m, 1-8.vi.1996, leg. Schillhammer, 15 (1 ex. NHMW) ; same as previous except: 300m, 16 (4 ex. NHMW) . Xiangkhouang " Xieng Khouang ": 21.iii.1915, leg. Vitalis, coll. R. Peschet (1 ex. MNHN) . Uncertain locality within Laos : "Bas-Laos": ii.1900, leg. Barthélemy (1 ex. MNHN) ; " Lakhon ", 1878, leg. Harmand, Coll. MAURICE REGIMBART 1908 (13 ex. MNHN) ; " Tonkin " 1886, leg. Langue (4 ex. MNHN) ; " Tonkin ", "central", 1911, leg. A. Krempf (1 ex. MNHN) ; " Tonkin ", "region de Chim-Hua et de Tuyen-Quan", 1901, leg. A. Weiss (2 ex. MNHN) ; " Tonpheng ", 29.v.1966, leg. "Native Collector" (1 ex. BPBM) ; same as previous except: 16.xii.1966 (1 ex. BPBM) . MALAYSIA: Melacca : leg. de Morgan (1 ex. MNHN) ; Pahang: 4 km W Rompin, " Selendang ", 29.iv-6. v.1993, leg. I. Jenis (3 ex. NHMW) ; same as previous except: leg. Strba (5 ex. NHMW) ; Pahang: Taman Negara Ntl. Prk. , 3°36′52″N 102°29′11″E, 21.viii.2003, leg. G. Svenson, GJS21080301 (5 ex. MSBA) . Perak: Kwala-Kangsar, Coll. MAURICE REGIMBART 1908 (2 ex. MNHN) ; Kwala- Kangsar , 1902, leg. Grubauer, Coll. Mus. Vindob. (3 ex. NHMW) . Sabah: Tawau Hills, Tawau River , 7-10.vi.1998, leg. J. Kodada & F. Ciampor (20 ex. NHMW) . Sarawak: " Baram ", 1910, leg. H.W. Smith (1 ex. MCZ) ; " Tuba ", 18.i.1979, leg. Gärdenfors, Hall, Hansson, & Samuelsson (15 ex. MZLU) ; Kapit , ca. 40km SE Kapit, iii.1994, leg. J. Kodada (9 ex. NHMW) ; Kapit, "Rumah Ugap vill.", Slut riv., 3-9.iii.1994, leg. J. Horák (12 ex. NHMW) ; same as previous except: leg. J. Horák, Jiří Hájek Collection (3 ex. NMPC) ; Kuching, 80km S Kuching, Kampung Ana Rais , 18.ii.1993, leg. M. Jäch (1 ex. NHMW) ; Miri , 8 km NE Bario, stream in jungle, 24.vi.2003, leg. D. Trávníček, Jiří Hájek Collection (1 ex. NMPC) ; Miri, Kelabit Hi., 6km E Bario, Pa Ukat , 1000m, 27.ii.1993, leg. M. Jäch, 15 (1 ex. NHMW) ; Miri, Gunung Mulu Ntl. Prk. (" Mulu N.P. "), Long iman, 4.iii.1993, leg. M. Jäch, 20 (1 ex. NHMW) ; same as previous except: 3-5.iii.1993, leg. Zettel, (14 e) (1 ex. NHMW) ; same as previous except: small stream, 4°0.207′N 114°49.267′E, 20.x.2006, leg. K.B. Miller, KBM20100601 (5 ex. MSBA) ; Miri, Sungai Kelimau , "ca. 1.3 km above mouth", 3°24′36″N 114°3′00″E, 12.ix.1980, leg. M.H. Ang, Acc. 4302-3 (EN-0002) (2 ex. ROME) ; Sri Aman, Batang Ai Ntl. Prk., Engkari riv., "E Bandar Sri Amman", 19-20.ii.1993, leg. Zettel, 7 (3 ex. NHMW) . MYANMAR: Mandalay: 8km E Pyin Oo Lwin, " Pwe Kauk Wf. ", 22°03.523′N 96°31.956′E, 1070m, 19.x.1998, leg. Schillhammer, 20 (1 ex. NHMW) . Tanintharyi: " Tenasserim ", Mus. Westerm (1 ex. ZMUC) , same as previous except: leg. Helfer (14 ex. NMPC) . THAILAND: " Siam ": Coll. MAURICE REGIMBART 1908 (1 ex. MNHN) ; THAILAND: viii.1984 (3 ex. ZMUC) . Chaiyaphum: Phu Khieo Wildlife Sanctuary , "Nam Prom", 4.iv.1994, leg. W. Shepard, WDS A 1053 (7 ex. NHMW) . Chanthaburi: 15km E Chanthaburi City, stream at Philiu Waterfall , 29.i.1995, leg. P.P. Chen (1 ex. NHMW) . Chiang Mai: " Soppong-Pai ", 1800m, 1-8.v.1993, leg. Pacholatko & Dembicky (1 ex. NHMW) . Chumphon: Khun Mae Yam Oum Wildlife Sanct., Haew Lome Waterfall water surf., 09°43′N 98°40′E, 122m, 22.v.2005, leg. Sites, Vitheepradit, & Prommi, L-785b (2 ex. UMRM) . Kanchanaburi: Amphur Sangkhla Buri, Heuy Kob , 15°13′N 98°22′E, 289m, 13.iv.2002, leg. UMC and CMU teams, gravel stream, L-339 (11 ex. UMRM) ; Amphur Sai Yok, Thong Pha Phum Reforestation Station, Mae Nam Noi , 14°31′N 98°37′E, 204m, 12.iv.2002, leg. UMC and CMU teams, L-335 (9 ex. UMRM) ; 30km N Thong Pha Phum, sm. Mount. Riv. , sec. veget, neustic, 14°58′11″N 98°38′35″E, 160m, 13.xii.2010, leg. Freitag, 22b (1 ex. NHMW) . Loei: Dan Sai , "Lomie Mt.", 1.iii.1955, leg. R.E. Elbel, ZML. 2010/ 356 (1 ex. MZLU) ; Na Haeo , river bank, 15.v.2003, leg. P. Grootaert, J. Constant, & K. Smets, Light trap (3 ex. IRSB) ; Phu Luang Wildlife Sanctuary , 700-900m, 8-14.x.1984, leg. Karsholt, Lomholdt, & Nielsen (8 ex. ZMUC) ; Phu Rua Nat. Prk., Nam Tok Huay Pai , waterfall, 10.vi.1998, leg. Sites, Simpson, & Vitheepradit, L-175 (1 ex. UMRM) . Mae Hong Son: " Ban Si Lang ", 19 19′N 97 59′E, 1200m, 23-31.v.1991, leg. Dembicky (1 ex. NHMW) ; Huai Sua Tao , v.1992, leg. Dembicky (1 ex. NHMW) . Mukdahan: Phu Pa Yon Ntl. Prk., Keang Pho Waterfall , 16°45.368′N 104°14.736′E, 314m, 23.iv.2004, leg. A. Vitheepradit, margin, L-634 (9 ex. UMRM) . Nakhon Nayok: Khao Yai Ntl. Prk. , ca. 700m, 29.ix-6.x.1984, leg. Karsholt, Lomholdt, & Nielsen (6 ex. ZMUC) . Nakhon Ratchasima: Khao Yai Ntl. Prk. , 14°20′N 101°30′E, 1000m, 26.iii.1992, leg. E. Hüttinger (10 ex. NHMW) ; Khao Yai N. D., 700-800m, 31. iv.1990, leg. E. Fuller (3 ex. NHMW) . Nan: Ban Pha Khap, 15-20.v.1992, leg. P. Pecholatko (2 ex. NHMW) ; Mae Charim Ntl. Prk., Nam Wa River , 18°36′N 100°59′E, 335m, 13.iii.2002, leg. CMU Team (2 ex. UMRM) . Phang Nga: Amphur Khura Buri, Tumbon Bang Won , 08°59′N 98°26′E, 45m, 27.iv.2002, leg. Vitheepradit & Kirawanich, gravel stream, L-375 (23 ex. UMRM) ; Khao Lak surr., 10. i.2003, leg. H. Forster (6 ex. NHMW) ; Khura Buri , "Baan Tumnang", W of Si Phang Nga Ntl. Prk., 29. xi.2006, leg. H. Zettel, 48 (4 ex. NHMW) . Phetchabun: 5 km E Sila, " Mae Nam Pa Sak ", 2.iii.1994, leg. W. Shepard, WDS A 1025 (1 ex. NHMW) ; Khao Kor Non-Hunting Area, Sridit Waterfall , 16°37′N 100°56′E, 702m, 11.v.2004, leg. Vitheepradit & Prommi, water surface, L-677 (1 ex. UMRM) . Rayong: Khao Chamao-Khao Ntl. Prk. (" Khao Chamao NP "), 12.xii.1990, leg. Jäch, 14 (1 ex. NHMW) . Sakon Nakhon: " Keek poo", 9.xi.1954, leg. R.E. Elbel ZML.2010/ 357 (1 ex. MZLU); " 11 km NE Kham Poem ", " Huai Ya ", 5.iii.1994, leg. W. Shepard, WDS A 1027 (4 ex. NHMW) . Saraburi: Khao Yai Ntl. Prk., Lamtok Khlong , 2.i.2008, leg. R.W. Sites, L-1025 (9 ex. UMRM) . Songkhla: Ton Nga Chang Ntl. Prk., stream at Buddhist temple, 30.i.1995, leg. B.J. Nichols, L-81 (3 ex. UMRM) ; same as previous except: 6.vii.1997, leg. R.W. Sites, L-127 (24 ex. UMRM) ; same as previous except: 9.vi.2001, L-236 (54 ex. UMRM) ; Khoa Nam Khang (" Khao Nam Chang "), SW Na Thawi ("SW Nathawee "), 13.i.1995, leg. R. Sites & B. Nichols (5 ex. UMRM) ; 102 km SE Amphur Hat Yai, Amphur Na Tawee, Khao Nam Khang Ntl. Prk. , 6°36′N 100°36′E, 100m, 15.vi.2001, leg. R.W. Sites, L- 246 (5 ex. UMRM) . Surat Thani: Khao Sok Ntl. Prk. , 5-9.vi.1999, leg. D. Šanc, Jiří Hájek Collection (5 ex. NMPC) ; same as previous except: 15.1.2003, leg. H. Forster (5 ex. NHMW) . Yala: Betong , "Gunung Cang dun vill.", 25.iii-22. iv.1993, leg. J. Strnad (1 ex. NHMW) . Uncertain locality within Thailand: Khao Yai Ntl. Prk. , 14.xi.1988, leg. Jäch, 2 (3 ex. NHMW) . VIETNAM: Đắk Lắk: ca. 2km SE Ban Don, Yok Don Ntl. Prk. H.Q., 12°53′N 107°48′E, 22-31.v.1997, leg. D. C. Darling & D.C. Currie, UV/MV light, ROM 974004 (3 ex. ROME) ; same as previous except: leg. D.C. Darling, D.C. Currie, & A. Guidotti, MV light, ROM 974019 (1 ex. ROME) ; 8km SW Ban Don, Yok Don Ntl. Prk., Dak Ken R., 12°53′N 107°48′E, 16-22.vi.1997, leg. B. Hubley, Dipterocarp forest, ROM 974105 (40 ex. ROME) . Gia Lai: 20 km N of Pleiku , 650m, 9.v.1960, leg. L.W. Quate (1 ex. BPBM) ; 25 km SW of Pleiku , 400m, 12.v.1960, leg. L.W. Quate (1 ex. BPBM) ; 40 km NW An Khe, Buon Luoi , 14°10′N 108°30′E, 620-750m, 28.iii-12.iv.1995, leg. Pacholatko & Dembicky (47 ex. NHMW) ; An Khe Dist., Tram Lap. Azun R., 2km NW on trail from forestry building, 14°27′N 108°33′E, 18.vi.1996, leg. B. Hubley & D.C. Currie, 1° rainforest edge/ coffee plantation, ROM 961059 (8 ex. ROME) ; An Khe Dist., 5.2km NE Tram Lap on forest road, Dacklest River , 14°24′N 108°33′E, 900m, 22-23. vi.1996, leg. B. Hubley & D.C. Currie, 200m upstream bridge/ stream margin/ deep pools, ROM 961086, ROMEnt Spec. No. 17529-17536 (8 ex. ROME) ; An Khe Dist., 3km E. Buoenloy, small stream 6km on logging road past Cha River , 25.vi.1996, leg. N. Orlov, ROM 961093 (1 ex. ROME) . Hòa Bình (" Hoa Binh "): 1919, leg. R.P.A. de Cooman, ZML.2010/ 355 (1 ex. MZLU) . Lâm Đ ồng: Fyan , 900-1000m, 11.vii-9. viii.1961, leg. N.R. Spencer (5 ex. BPBM) ; 15km SW Bẚo Lộc, 11°27′N 107°43′E, 900m, 22-24.iv.1995, leg. Pacholatko & Dembicky (8 ex. NHMW) . M'Đrăk : E of Buon Ma Thuot ("BanMeThuot"), 400-600m, 8-19.xii.1960, leg. C.M. Yoshimoto (5 ex. BPBM) . Ngh ệ An: Phúc SƠn (" Phuc-Son "), xi-xii, leg. H Fruhstorfer, ZML.2010/ 353 (1 ex. MZLU) ; same as previous except: Coll. MAURICE REGIMBART 1908 (1 ex. MNHN) . Ninh Thu ận: Phan Rang ("Pha- Rang "), leg. H. Fruhstorfer, (1 ex. NHMW) ; same as previous except: ZML.2010/ 351-352 (2 ex. MZLU) . Qu ảng Tr ị: "Cua Tung", H.C. Fall Collection (1 ex. MCZ) , Da Krong Nature Reserve , 16°37′N 106°47′E, 5-10.vii.2011, leg. J. Constant & J. Bresseel, day collecting, I.G.:31.933 (4 ex. IRSB) ; same as previous except: 16°37′N 106°47′E, Light trap, I.G.:31.933 (1 ex. IRSB) . Uncertain localities within Vietnam : "Houtabo", "Se-Souk", 1897, leg. J.M. Bel (1 ex. MNHN) ; " Karyu Danar ":, 200m, 13-28.ii.1961, leg. N.R. Spencer (10 ex. BPBM) . Uncertain localities: "Inde, Bellary, ou Ceylan", 1896, leg. De Morgan (3 ex. MNHN) ; "Indes Or.", "Marc 1196-36" (1 ex. MNHN) ; " Cochinchine ", 1878, leg. Pierre (2 ex. MNHN) ; " Cochinchine ", ii.1900, leg. Barthélemy (1 ex. MNHN) ; " Muang You ", 26.v, coll. R. Peschet (1 ex. MNHN) . No locality information: "Patra Ignota" (1 ex. MNHN) ; [illegible handwriting in ink] (1 ex. NMPC) ; [illegible handwriting in ink], coll. R. Peschet (1 ex. MNHN) ; ZML. 2010/ 359 (1 ex. MZLU) ; 334, ZML.2010/ 358 (1 ex. MZLU) ; leg. Plason, Coll. Mus. Vindob. (1 ex. NHMW) ; 1871, " Fieber / Mulmeir ", Coll. Mus. Vindob. (1 ex. NHMW) ; Mus. Westerm (2 ex. ZMUC) ; [illegible handwriting in pencil] (1 ex. ZMUC) .

Type Locality. Java, Indonesia .

Diagnosis. Orbital ridge with yellow lateral margins; labrum highly elongate and in the form of an isosceles triangle ( Fig. 1A ). Antenna with six flagellomeres ( Fig. 2C ). Dorsally olive green to bronzy brown; yellow lateral margins complete on elytra, extending to elytral apices, nearly always interrupted in basal third by a dark spot, associated in males with swelling for reception of fore leg ( Fig. 1A ). Elytral apices spinose, apicolaterally with sawtooth-like spines; sutural angle produced to a short point; one large parasutural spine; last sawtooth-like spine at the epipleural angle larger and more projecting than the rest, often strongly produced and spinose ( Fig. 1A ).

Porrorhynchus marginatus can be distinguished from all other species of the genus in having the orbital ridge with yellow margins and the elytral apices with a single parasutural spine and buzzsawlike serration apicolaterally ( Fig. 1A ). The species most similar to P. marginatus is P. depressus ( Fig. 1D ), however, these two species drastically differ in size (with P. marginatus normally being much larger) and the shape of the labrum (with that of P. marginatus being much more elongate and acuminate and in the form of an isosceles triangle), Finally, the non-overlapping distributions of the two species should easily separate the two.

Description. Size: ♂ L: 13.7 – 18.1 mm, W: 7.6–10.8 mm; ♀ L: 12.2–15.1 mm, W 7.1–8.7 mm. Habitus: Medium to very large members of genus; body form often tear-drop shaped, broadest posteriad middle, attenuated anteriorly, especially in large males, other populations elongate oval, evenly attenuated anteriorly to posteriorly, especially in females; in lateral view, convex, strongly humped in scutellar region, depressed posteriorly/ anteriorly; in anterior and posterior views, steeply sloped towards lateral margins from strongly humped scutellar region. Coloration: Dorsally head, pronotum, and elytra olive green to bronzy brown; labrum yellow basomedially; pronotum/ elytra with yellow lateral margins; elytral margin apicolaterally dark, turquoise-blue reflections apicolaterally mediad end of yellow lateral margins in some individuals; venter yellow; ultimate maxillary palpomere not darkened; fore legs with tibia black in proximal 1/2, profemora black api- cally. Head: Vertex with even covering of lightly impressed punctures, separated from nearest puncture by ca. 2–3X diameter of a puncture; orbital ridge with yellow margin; frons similarly punctate as vertex, punctures mostly concentrated apicomedially, fronto-lateral margins very lightly wrinkled to non-wrinkled, frontoclypeal suture with posterior margin nearly straight, lateral margins nearly straight, meeting posterior margin at ca. 120° angle; clypeus with punctation most evident at anterior margin, punctures separated from nearest puncture by ca. 2–3X diameter of a puncture, becoming more densely spaced anteriorly; antennal flagellum with 6 complete flagellomeres, ultimate flagellomere at least 2X longer than penultimate, trapezoidal; labrum in form of isosceles triangle, punctation absent basomedially, in association with yellow coloration, strongly present apically, punctation well-impressed and dense, separated from nearest puncture by 0.5–1.5X diameter of a puncture; maxillary and labial palpi similar in shape ( Fig. 8D ), both hatchet-form with anterior margin of maxillary palp and ventral margin of labial palp weakly curved, posterior margin of maxillary palp/dorsal margin of labial palp more strongly curved, apex of both truncate. Thorax: Pronotum with even covering of finer, weakly impressed punctures separated from nearest puncture by 2–3X diameter of a puncture, reticulation less impressed medially, becoming very well-impressed laterally, very shallow transverse depression often present medially, lateral marginal depression present; protrochanteric setose patch situated apicolaterally; protibial spine projecting forward; male protarsi not laterally broadened, not noticeably dorsally convex, shape as in Fig. 8A , ultimate male protarsomere ca. 2X as long as wide; ultimate protarsomere of female ca. 1.5X length of penultimate; elytra with reticulation effaced in scutellar and sutural regions, reticulation present apically/laterally, being very strongly impressed marginally, elytral discs with even covering of finely impressed, punctation, distance between nearest punctures ca. 2–3X diameter of a puncture; lateral marginal depression broad, strongly expanded posteriad humeral region; yellow lateral margin complete, ending apicolaterally at elytral apices, nearly always interrupted in basal 1/3 by darkly colored spot, in males associated with swelling created by cavity for reception of fore leg, apicolateral margins of elytra with triangular sawtooth-like spines, final spine at the epipleural angle often strongly elongate, spine-like, elytral apices spinose ( Fig. 1A ), with single parasutural spine, sutural angle produced; mesoventral apex not noticeably acuminate, evenly narrowed basally to apically; meso- and metacoxae similar, mesocoxae with posteriorly projecting process, processes strongly acuminate, almost spine-like ( Fig. 8C ); male mesotarsal claws as in Fig. 8E , with ventral margin flatly rounded, anterior claw not significantly narrowed apically. Genitalia: Aedeagus ( Fig. 10 ) with median lobe ca. 5/6 length of parameres, parallel-sided in basal 1/2, some populations with medial constriction, moderately laterally expanded in apical 1/2, acuminate in apical 1/4, apex truncate; in lateral view, apex briefly and strongly curved dorsally; parameres in dorsal view with lateral margins briefly expanded in apical 1/3, setose in apical 1/5, apex with apicomedial margin straight to oblique reflexed in apical 1/5, medial margin arcuately reflexed after apical 1/5 until basal 1/2; lateral margins often constricted in basal 1/5; in lateral view, ventral margin of parameres often evenly curved anteriorly to posteriorly. Female reproductive tract ( Fig. 13C ) with narrow, elongate, tubiform spermatheca; gonocoxae short, lateral margin straightly angled towards apex, apex obliquely truncate.

Sexual Dimorphism. Males tend to be larger in size than females; some males exhibit a broader body form, having their outline laterally expanded posteriad elytral mid-length, giving large males a more attenuated feel anteriorly. Females tend to be much more elongate in appearance, being evenly attenuated posteriorly and apically.

Variation. This widespread species is highly variable in body form and size ( Fig. 9 ). Specimens examined from more northern mainland latitudes tend to be more elongate and narrowly oval in overall body form and with a much more acute labrum ( Fig. 9B, C, D ), with some larger specimens reaching some fairly long body lengths ( Fig. 9B ). Specimens from along the Malay Peninsula tend to be smaller in overall body length, with a more evenly oval body form and broader labrum ( Fig. 9F, G, H ). Specimens from Borneo run the gamut of body forms, but notably include a unique race containing very large and broad males (described as a formal subspecies, D. marginatus mjobergi , Fig. 9O ). The largest specimens of P. marginatus come from East Kalimantan ( Fig. 9O ). These specimens also have relatively blunt metacoxal processes relative to other populations ( Fig. 8Q ).

Distribution. The most widely distributed species in the genus, P. marginatus is found throughout most of Southeast Asia from as far northwest as Zayü Co., China ( Jäch et al. 2012), east to Vietnam, and south to Java, including Borneo, but notably absent from the Philippines and east of Wallace’ s line ( Fig. 14 ).

Biology. Label data support the previous observation ( Ochs 1927b) that P. marginatus is found in smaller forested streams, often above 100 m and up to 1,000 m. This species has been implicated as sensitive to water quality, being found only in streams in the Malay Peninsula not contaminated by tailings from tin mines ( Ochs 1927b).

Discussion. This species exhibits great variation in body form ( Fig. 9 ). However, similar variation was not exhibited elsewhere in external morphology ( Fig. 8 ). The northern populations exhibiting a more narrow body form, formally described by Régimbart (1877a) as P. tenuirostris , exhibit no other significant variation. Régimbart (1882) identified his “ tenuirostris ” as being mere variation and synonymized it himself. Only later would the name be re-instated by Ochs (1926). Given this name was only based on variation in outline, with other southern populations having a narrow outline (i.e., Fig. 9I ), this name is formally synonymized here again.

The aedeagus shows considerable variation ( Fig. 10 ). Most populations have a narrow elongate median lobe that is weakly constricted medially and strongly acuminate apically. Populations from Sumatra ( Fig. 10I, J, K ) have a shorter and broader aedeagus, with a thicker median lobe. However, all populations, including the Sumatran, exhibit the same general form of the median lobe, being laterally expanded in their apical half, then acuminate in the apical quarter with a truncate apex, and having the same length to paramere proportions, being just shorter than the parameres. Importantly, all medial lobes have the apex curved dorsally in lateral view. The greatest degree in variation was exhibited by the apex of the parameres. Specimens from Sumatra have broad and mostly rounded apices to the parameres ( Fig. 10J, K ), while other populations have strongly truncate apices ( Fig. 10D, E, H, I ), and many with the apex more-or-less evenly rounded ( Fig. 10A, F, L, M, N ). However, all the parameres had a consistent obliquely truncate medial margin to the apex and a lateral expansion in their apical third. Furthermore, the difference in paramere morphology could not be attributed to any single region. The broader median lobe of the Sumatran populations was the only consistent morphological difference exhibited among the aedeagi of the P. marginatus specimens examined. However, this does not correspond to any formally described subspecies.

Porrorhynchus marginatus mjobergi was described from very large specimens collected from Borneo’ s Mount Dulit. Other specimens from Borneo are similarly robust and among the largest specimens examined. However, the broad body size is not consistent among specimens from Borneo. Specimens from East Kalimantan match P. m. mjobergi well and do exhibit a minor unique morphology apart from the more robust dorsal habitus of males. The metacoxal apex ( Fig. 8Q ) has broader and more rounded apices. The labra of the specimens examined are also broader and rounder than those of other populations. The aedeagus, however, exhibits no substantial difference from other populations ( Fig. 10N ). Given the potential isolation of the population to the mountains of central Borneo and some of the unique features exhibited, P. marginatus mjobergi may be deserving of subspecies status pending a phylogenetic analysis. However, morphologically, there is nothing to merit continuing this distinction as a formally named taxon until phylogenetic evidence gives credence to its distinction.

While the species has been suggested to be sensitive to water quality, it has a very large range, unlike the two other members of Porrorhynchus s. str. Given its large range and common occurrence in museums, it is not likely of conservation concern currently. We propose the common name of the margined snouted whirligig for P. marginatus .

Figures

Fig. 1. Porrorhynchus species, dorsal habitus. A) P. marginatus, B) P. landaisi, C) P. indicans, D) P. depressus, E) P. misoolensis. Scale bar = 5 mm.

Fig. 2. Porrorhynchus species, right antenna (anterior view above, posterior view below. A) P. landaisi, B) P. indicans, C) P. marginatus, D) P. depressus. Scale bars = 0.5 mm.

Fig. 3. Porrorhynchus marginatus, male. A) Protrochanter, marked area shows protrochanteric setose patch, scale bar = 400 μm, B) Protrochanteric setose patch, scale bar = 50 μm.

Fig. 4. Porrorhynchus marginatus, male, profemur. Scale bar = 1 mm.

Fig. 8. Porrorhynchus marginatus. Specimen from Chumphon, Thailand: A) Protarsus, scale bar = 1 mm, B) Metacoxal apex, scale bar = 0.5 mm, C) Mesocoxal apex, scale bar 0.5 mm, D) Maxillary (above) and labial (below) palpi, scale bar = 0.5 mm, E) Mesotarsal claws, scale bar = 0.5 mm. Specimen from Khammouane, Laos: F) Protarsus, scale bar = 1 mm, G) Metacoxal apex, scale bar = 0.5 mm, H) Mesocoxal apex, scale bar 0.5 mm, I) Maxillary (above) and labial (below) palpi, scale bar = 0.5 mm, J) Mesotarsal claws, scale bar = 0.5 mm. Specimen from Dac Lac, Vietnam: K) Protarsus, scale bar = 1 mm, L) Metacoxal apex, scale bar = 0.5 mm, M) Mesocoxal apex, scale bar = 0.5 mm, N) Maxillary (above) and labial (below) palpi, scale bar = 0.5 mm, O) Mesotarsal claws, scale bar = 0.5 mm. Specimen from East Kalimantan, Malaysia: P) Protarsus, scale bar = 1 mm, Q) Metacoxal apex, scale bar = 0.5 mm, R) Mesocoxal apex, scale bar 0.5 = mm, S) Maxillary (above) and labial (below) palpi, scale bar = 0.5 mm, T) Mesotarsal claws, scale bar = 0.5 mm. Specimen from Manna, Sumatra: U) Protarsus, scale bar = 1 mm, V) Metacoxal apex, scale bar = 0.5 mm, W) Mesocoxal apex, scale bar = 0.5 mm, X) Maxillary (above) and labial (below) palpi, scale bar = 0.5 mm. Specimen from Java: Y) Protarsus, scale bar = 1 mm, Z) Metacoxal apex, scale bar = 0.5 mm, AA) Mesocoxal apex, scale bar 0.5 mm, BB) Maxillary (above) and labial (below) palpi, scale bar = 0.5 mm, CC) Mesotarsal claws, scale bar = 0.5 mm.

Fig. 9. Porrorhynchus marginatus, dorsal habitus showing populational variation. A) Mandalay District, Myanmar, B) Loei Province, Thailand, C) Khammouane Province, Laos, D) Đắk Lắk Province, Vietnam, E) Saraburi Province, Thailand, F) Chumphon Province, Thailand, G) Songkhla Province, Thailand, H) Pahang, Malaysia, I) Gunung Leuser, Sumatra, J) West Sumatra, Sumatra, K) Siberut Island, Sumatra, L) Manna, Sumatra, M) Java, N) Kapit District, Sarawak, Malaysia, O) East Kalimantan, Indonesia. Scale bars = 5 mm.

Fig. 13. Porrorhynchus species, female reproductive tract. A) P. landaisi, B) P. indicans, C) P. marginatus, D) P. depressus, E) P. misoolensis. More heavily sclerotized areas indicated in gray. Scale bars = 1 mm.

Fig. 14. Map showing distribution of Porrorhynchus s. str. species. Triangles = P. landaisi; circles = P. marginatus; square = P. indicans.

Fig. 17. Type specimens. A) Porrorhynchus marginatus, holotype and label, B) Porrorhynchus depressus, holotype, C) Dineutus depressus jamurensis, paratype, D) Porrorhynchus tenuirostris, lectotype and labels, E) Dineutus depressus moszkowskii, holotype, F) Dineutus depressus versteegi, holotype, G) Dineutus marginatus mjobergi, lectotype and labels, H) Dineutus depressus misoolensis, paratype.

Fig. 5. Porrorhynchus indicans aedeagus. A) Dorsal view, B) Lateral view, C) Ventral view. Scale bar = 1 mm.

Fig. 10. Porrorhynchus marginatus, aedeagi, lateral and dorsal views, showing populational variation. A) Mandalay District, Myanmar, B) Loei Province, Thailand, C) Khammouane Province, Laos, D) Đắk Lắk Province, Vietnam, E) Saraburi Province, Thailand, F) Chumphon Province, Thailand, G) Songkhla Province, Thailand, H) Pahang, Malaysia, I) Gunung Leuser, Sumatra, J) Siberut Island, Sumatra, K) Manna, Sumatra, L) Java, M) Kapit District, Sarawak, Malaysia, N) East Kalimantan, Indonesia. Scale bars = 1 mm.