Tijdschrift voor Entomologie 160 (2017) 89–138

An initial survey of aquatic and semi-aquatic Heteroptera (Insecta) from the Cardamom Mountains and adjacent uplands of southwestern , with descriptions of four new species Dan A. Polhemus

Previous collections of aquatic Heteroptera from Cambodia have been limited, and the biota of the country has remained essentially undocumented until the past several years. Recent surveys of aquatic Heteroptera in the Cardamom Mountains and adjacent Kirirom and Bokor plateaus of southwestern Cambodia, coupled with previous literature records, demonstrate that 11 families, 35 genera, and 68 species of water bugs occur in this area. These collections include 13 genus records and 37 species records newly listed for the country of Cambodia. The following four new species are described based on these recent surveys: Amemboa cambodiana n. sp. (Gerridae); Microvelia penglyi n. sp., Microvelia setifera n. sp. and Microvelia bokor n. sp. (all Veliidae). Based on an updated checklist provided herein, the aquatic Heteroptera biota of Cambodia as currently known consists of 78 species, and has an endemism rate of 7.7%, although these numbers should be considered provisional pending further sampling. Keywords: Heteroptera; Cambodia; water bugs; new species; new records Dan A. Polhemus, Department of Natural Sciences, Bishop Museum, 1525 Bernice Street, Honolulu, HI 96817 USA. [email protected]

Introduction of collections or species records from the country in Aquatic and semi-aquatic Heteroptera, commonly the period preceding World War II. Following that known as water bugs, are a group of worldwide dis- war, the country’s traumatic social and political his- tribution with a well-developed base of taxonomy. As tory left it isolated until the 1990s, and therefore such, they have proven to be a useful entomological unvisited by collectors. Despite a renewed interest component for biodiversity surveys in many parts of in the survey of aquatic Heteroptera in neighbor- the world. This paper provides the results of targeted ing countries, such as and , from collections of this group in the Cardamom Moun- the mid-1980s onward, Cambodia continued to re- tains area of southwestern Cambodia. The paucity main overlooked and unvisited, in part because of of previous work is illustrated by the fact that of the the hazards involved with the numerous land mines 78 species listed in this paper, 37 represent new and that had been planted throughout the country. Only previously unpublished records for the country. in 2017 was a first preliminary checklist of aquatic The aquatic Heteroptera biota of Cambodia re- Heteroptera published for the country, containing mained essentially un-sampled until the last several records of 41 species, based primarily on collec- years. In contrast to other French colonial possessions tions from nine widely scattered localities (Zettel in Indochina, there seems to be no documentation et al. 2017). By contrast, the current report, although

Tijdschrift voor Entomologie 160: 89–138, Appendices 1–2, Figs 1–58. [ISSN 0040-7496]. brill.com/tve © Nederlandse Entomologische Vereniging. Published by Koninklijke Brill NV, Leiden. Published 15 December 2017. DOI 10.1163/22119434-00002068 Downloaded from Brill.com10/07/2021 06:11:13PM via free access

90 Tijdschrift voor Entomologie, volume 160, 2017 limited to the Cardamom Mountains and adjacent plateaus that extend progressively to the southeast highlands in the southwestern third of Cambodia, (Fig. 1); these latter two plateaus are also referred represents a more targeted and comprehensive set of to as the Elephant Mountains. All these areas were aquatic Heteroptera collections from 27 more geo- sampled in the course of the present surveys. graphically proximal localities. The Cardamom Mountains lie in southwestern Cambodia, south of the Tonle Sap basin, and west of the Mekong River. The overall form of the uplift Description of study area is that of a sandstone cuesta, dipping to the south- Although the central portion of Cambodia is com- west, and breaking to the northeast. The mountain posed of extensive lowlands that border the Mekong slopes are for the most part gentle, and the summit River and its tributary Tonle Sap river and lake sys- ridges of relatively even height, with the highest el- tem, the country also contains various upland areas. evations being Phnom Samkos at 1,717 m, Phnom These include the narrow and elongate Dangrek Tumpor at 1,516 m, and Phnom Kmoch at 1,220 m. Range that forms the border with Thailand along the Although sometimes also considered as part of the margin of the in Oddar Meanchey Cardamom Mountains, the 1813 m and Preay Vihear Provinces; the southern terminus massif to the northeast is of completely different geo- of the Annamite Mountains that extend into the Vi- logical origin, and is topographically separated from rachey National Park area of Ratnakiri Province in the Cardomom uplift by an intervening lowland bar- the far northeast; a western extension of the basalt rier; as such, is in not considered as part of the Car- plateaus typical of the Vietnamese Central High- damom Mountains for the purposes of this report. lands which extend into the eastern Mondulkiri The Cardamom Mountains also continue westward Province; and the extensive Cardamom Mountain some distance into Thailand, and isolated outliers of uplift that occupies the southwest quarter of the the uplift also form offshore islands in the Gulf of country, primarily in the provinces of , Koh Thailand, such as Phu Quoc Island, which is admin- Kong, Kampong Speu, and . istered by Vietnam. It is this latter Cardamom uplift that was the focus Aquatic diversity is influenced by stream of the current study. The Cardamom uplift is com- bed profile and composition, which is in turn in- posed of three major geomorphological units that lie fluenced by regional geology. Although a number of along the western margin of the Kampot Fold Belt studies have examined the overall tectonic setting of (Fyhn et al. 2016), and are separated by interven- Indochina, local field geology remains poorly con- ing gaps below 250 m elevation: the Cardamom strained, and published geological maps are often Mountains themselves, and the Kirirom and Bokor inaccurate. As such, the discussion below is based

Fig. 1. View to the southeast from a high point on the Kirirom Plateau at 715 m elevation, showing typical topog- raphy and vegetation of the southwestern Cambodian highlands. The forest in the foreground on the left side of the valley is dominated by Tenassarim pine (Pinus merkusii), while the forest on the right side of the valley is a wetter semi-deciduous broadleaf forest. The blue ridge in the distance is the Elephant Mountains, terminating in the Bokor Plateau visible in the left-central portion of the uplift, and supporting montane evergreen broadleaf . Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 91 largely on mining company and NGO reports (Save Sap lake and river system may be a graben (a down- Cambodia’s Wildlife 2006; Earth Worx 2009; JICA ward-dropped fault block) lying between the elevat- 2010). Based on these sources, the surface geology ed Mesozoic sandstone exposures of the Cardamom of the Cardomom Mountains in the areas covered Mountains and respectively (Run- during the current survey consists of Mesozoic del 1999). Whatever its original mode of genesis, the sandstone formations of Triassic to Cretaceous age Tonle Sap basin is now infilled with Quaternary to with interbedded conglomerates, shales, evaporites recent sediments, many of them sandy and derived and coal measures, all formed in continental mar- from the bordering mountains. Rivers traversing the gin or shallow-water marine environments. These lowlands between the Cardamom Mountains and sandstones appear to be correlative with those of the lake, such as the Bori Bo River sampled dur- the Khorat Plateau of eastern Thailand (Fyhn et al. ing this study, thus tend to be shallow and braided, 2010, 2016), and although the stratigraphy and pe- ­occupying broad, sandy, unshaded beds, and support trology of the Thai formations have been described aquatic insect species assemblages different from in detail by LaMoreaux et al. (1958), no similarly de- those seen in the rocky mountain foothills. tailed treatment is currently available for Cambodia. The Mesozoic sandstones of Cambodia have also Based on the work of LaMoreaux et al. (1958), and been partially eroded, creating many small windows mining company reconnaissance, the Cambodian which reveal the underlying Palaeozoic basement sandstones as a whole consist of a lower Triassic se- rocks, consisting of metamorphic and granitic forma- quence that is moderately folded and forms subdued tions (Earth Worx 2009). These basement rocks are topography, unconformably overlain by a Jurassic more broadly exposed in the northwestern section to Cretaceous sequence that is only gently folded of the Cardamom uplift. The Mesozoic sandstones (Earth Worx 2009). In eastern Thailand the upper have also been intruded at various points by small sequence is generally horizontal and forms large, to medium-sized dioritic to granitic plugs. Most of flat-topped, mesa-like hills, while in the Cardamom these intrusive bodies have large, irregular hornfels Mountains this sequence is tilted, dipping to the halos created by contact metamorphosis. In some southwest toward the . The older cases hornfels areas without apparent intrusives in- Triassic sandstone series is not extensively exposed in dicate the presence of plugs at a shallow depth below the Cardamom Mountains, but does crop out at the the current erosion surface. Because geological maps northwestern end of the range, and in small areas of Cambodia are incomplete at a local scale, there at the eastern end of the north slope as well (Save are often many more of these small-sized intrusive Cambodia’s Wildlife 2006). bodies present than currently indicated. The result The majority of the streams sampled during this of these processes is that even in areas with a pre- survey thus lay in areas dominated by sandstone ex- dominantly sandstone surface petrology, streambeds posures. These streams often traverse long reaches can be found with a more varied mixture of rock floored by sheets of sandstone bedrock, with little types in their cobbles and gravels, as was seen during fine substrate, and as such have poorly developed the present survey at the O Sarb Morth stream near hyporheic zones, as well as poor catchment buffer- Vealveang in , at the Sva Slab River ing capacity for heavy rainfall events, rendering their along the base of the Kirirom Plateau, and in rivers discharge patterns extremely flashy. The main chan- draining the Aural District of Kampong Speu Prov- nels of these catchments therefore represent harsh ince. Such systems have species assemblages which environments for aquatic , many of which differ from, and are often richer than, those seen in concentrate instead along the stream margins or in the sandstone-bedded catchments. riparian rheocrenes. In addition, the sandstone par- Forest cover is relatively intact in the Cardamom ent material in these catchments weathers to acidic Mountains as a whole, particularly in comparison lithosols (Rundel 1999), runoff from which creates to other areas of Indochina. The soils of the uplift acidic amber-colored waters high in tannins. The re- are generally sandy, relatively poor in nutrients, and sult is that these sandstone-bedded streams were ob- in many cases form only a thin layer over the un- served to support lower species richness for aquatic derlying bedrock. This phenomenon is particularly Heteroptera in comparison to those flowing in sand evident in certain ridgetop areas where balds, or veals, or cobble beds derived from other rock types. develop, having a vegetation of low-stature grasses As noted, the Mesozoic sandstones of the Carda- and sedges, sometimes with scattered stands of Me­ mom Moutains dip southwest, toward the Gulf of laleuca or Tenasserim pines, Pinus merkusii (Webb Thailand, and break away as scarps to the northeast, 2005). The result of these poor soil characteristics facing the Tonle Sap river and lake basin. In addi- is that agricultural development has been limited in tion, the entire uplift tilts downward along strike (its these mountains, except along certain valley floors longitudinal axis) from northwest to southeast. This which contain a thicker fill of more fertile alluvium, suggests that the depression containing the Tonle or in areas where localized basalt flows have formed Downloaded from Brill.com10/07/2021 06:11:13PM via free access

92 Tijdschrift voor Entomologie, volume 160, 2017 richer soils. In these areas rice and tree crops can be generally flow in rocky, high gradient beds (Fig. 7), grown, as was observed at Thmar Bang village, in and exhibit significant annual variations in dis- the Arang River drainage. Otherwise, much of the charge, with wet season total flows being very high. original forest cover still remains at the present time Many of the larger rivers in this sector have now been in the headwaters of most major stream catchments, widely dammed for hydropower, changing their an- which has conserved their aquatic habitats. nual discharge patterns, sediment loads, and biotic The northwest-to-southeast orientation of the characteristics. The Areng River, visited during this Cardamom Mountain axis has also produced a no- study, is the major exception, being still undammed. table difference in precipitation on the southwestern On the Tonle Sap side of the range, draining to vs northeastern flanks of the range. The southwest- the Mekong River, streams have lower base flow, are ern slopes, facing the Gulf of Thailand, receive high perennial to intermittent, and occupy lower gradi- rainfall, 3600–5300 mm per annum, depending on ent beds of cobbles or sand (Figs 8, 9). Rivers here elevation. By contrast, the northeastern slopes of the are also shallower, and often braided in their lower range are significantly drier, with rainfall in the range reaches. Annual peak discharges are much lower, and of 1400–2000 mm per annum (Rundel 1999), and few dams are present. Very few perennial streams with some areas in the adjacent lowlands receiving were observed on the northeast side of the Carda- less than 1300 m. This difference in rainfall is reflect- mom Mountains at elevations above 300 m, even in ed in the character of the vegetation spanning the the rainy season. As a result, the samples undertaken uplift, with taller stature, closed canopy, evergreen during the current surveys were made primarily from rainforest on the windward southwestern slopes (Figs the wet, southwestern face of the mountains, or from 2, 3), contrasting with lower stature, open canopy, streams exiting the mountain foothills at modest el- mesic to dry forests, often seasonally deciduous to evations in the Mekong River drainage. varying degrees, on the leeward northeastern slopes The Cardamom uplift extends southeastward (Figs 4–6). In particular, to the lee of the crest, the through the Kirirom and Bokor plateaus, known upper elevation forests are mesic evergreen forma- collectively as the Elephant Mountains, which are of tions, intergrading into semi-deciduous forests in the same geological composition as the Cardamom the foothills, while the lower elevation forests at the Mountains (Rundel 1999), although with their stra- base of the mountains are dry deciduous dipterocarp ta more flat-lying rather than tilted southwest, and forests, often dominated by Dipterocarpus obtusifolius they are treated as part of the same general orogeny (Rundel 1999). for purposes of this report. The Kirirom Plateau lies The disparate distribution of precipitation across on the border of Koh Kong and Kampong Speu the Cardamom uplift also manifests itself in effects provinces, reaching a maximum elevation of 705 m, on hydrology. On the Gulf of Thailand side of the and is composed of an elevated, relatively horizontal- mountains there are numerous perennial streams lying block of Jurassic to Cretaecous sandstone. and rivers at elevations from sea level up to at least Similar to the Cardamom Mountains, the Kirirom 550 m, some of them amber water systems. These Plateau possesses wet evergreen broadleaf forests on

Fig. 2. Wet lowland evergreen broadleaf forest near Thmar Bang village at about 400 m elevation, on the southeast- ern flank of the Cardamom Mountains facing the Gulf of Thailand. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 93

Figs 3–6. Exemplar forest formations of the southwestern Cambodian highlands. — 3, Wet montane broadleaf rainforest, Bokor Plateau summit, 1000 m; 4, middle elevation pine forest dominated by Pinus merkusii, Kirirom Plateau, 700 m; 5, semi-deciduous broadleaf forest, Cardamom Mountain foothills at Rolak village, 150 m; 6, dry deciduous broadleaf forest dominated by Dipterocarpus obtusifolius, northeastern base of Kirirom Plateau, 100 m. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

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Figs 7–10. Exemplar freshwater habitats of southwestern Cambodia. — 7, Stream in bed of sandstone plates on the road to Thmar Bang village, 355 m elev., Koh Kong Prov., CL 6017; 8, stream in semi-deciduous broadleaf forest at Rolak village, along the eastern edge of the Cardamom Mountains, 145 m elev., Kampong Speu Prov., CL 6041; 9, lowland stream bordered by bamboo east of Aural, flowing in a bed of sand and granitic cobbles derived from the Phnom Aural massif, 75 m elev., Kampong Speu Prov., CL 6044; 10, upland pond surrounded by montane rain forest on the Bokor Plateau, 985 m elev., Kampot Prov., CL 6036. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 95 its southwestern flank facing the Gulf of Thailand, to ecological conditions greatly changed from those and dry dipterocarp forest on its northeastern flanks that originally prevailed. In addition, widespread use facing the central Cambodian plain. The gently roll- of pesticides and other agricultural chemicals have ing summit of the plateau is covered in an extensive further impacted these lowland systems. Despite open forest of Pinus merkusii (Figs 1, 4), the largest this, certain lowland sites may still be found which such stand in Cambodia (Rundel 1999). The stream support relatively intact assemblages of genera and valleys on the plateau summit contain a floristically species not seen at higher elevations. rich evergreen to semi-deciduous broadleaf mesic forest, which often continues downslope on the drier northeastern side as a narrow band of riparian gal- Material and methods lery forest traversing the pine and dry dipterocarp Collections of aquatic Heteroptera were made dur- zones. Streams draining the southwestern flanks of ing two trips to Cambodia, from 30 August to 2 the Kirirom Plateau are perennial and high volume, September 2015, and again from 21 May to 4 June often flowing in channels of sandstone bedrock, as at 2016, respectively. Specimens were obtained by vi- Thmor Roung, or in beds of mixed boulders, rocks sual searching and hand netting, with the average and cobbles. By contrast, streams draining the drier amount of time spent at a given station being one interior face of the plateau on the northeast side are hour. Familiarity with the ecology of the groups lower volume or seasonally intermittent, dropping involved is a prerequisite for such rapid survey pro- over sandstone ledges, as at the waterfall near Cham- tocols, since many species inhabit particular circum- bok, or flowing in sandy beds. The northeast corner scribed microhabitats not intuitively obvious to a of the Kirirom Plateau abuts an exposure of rhyolite non-specialist. All of the voucher specimens collect- and dacite basement rock, which forms numerous ed were preserved in 75% ethanol and transported to bedrock chutes and rapids in the channel of the Sva the Bishop Museum in Honolulu, Hawaii (BPBM) Slab River that curls around the base of the plateau for detailed analysis and identification. Synoptic se- on this side. ries were dry mounted on pins or points, with dupli- The Bokor Plateau, lying to the southwest of cates retained in alcohol. Voucher specimens from the Kirirom Plateau beyond the low pass at Pich the collections obtained during the course of these Nil where Highway 4 crosses the range, is another surveys are deposited in the Bishop Museum, with large block of Jurassic to Cretaceous sandstone, but holotypes of new species described and duplicates of is more significantly elevated than Kirirom, reaching other species where available placed in the United a maximum elevation of 1081 m. The southwestern States National Museum of Natural History, Smith- flank of the plateau rises abruptly from the narrow sonian Institution, Washington, DC (USNM). All coastal plain, and therefore receives a significant specimens listed were collected by the author unless amount of precipitation, having the highest average otherwise noted. Measurements in the new species annual rainfall in Cambodia, although rivers in this descriptions are given in millimeters. area are short and with very steep profiles, falling The stations sampled for aquatic insects in south- over sandstone ledges. The extensive Kampot River western Cambodia are listed below. Latitudes and system drains the northeastern flank of the plateau, longitudes were taken using a Garmin GPS 45 hand- accumulating much of the runoff from the very wet held global positioning system. Altitudes were taken summit area, and is the site of a large hydroelectric using an alitimeter reading in feet (reading given in dam. The plateau summit itself lies near 1000 m brackets), with metric conversions provided. Wa- and is relatively level, with a dense, tangled upland ter temperatures were obtained using a hand-held broadleaf evergreen forest (Fig. 3) containing numer- thermometer, with the bulb 2.5 cm below the water ous small streamlets and ponds (Fig. 10). These cold, surface. CL numbers refer to a collection number- very wet uplands harbor aquatic Heteroptera species ing system used by the author to cross-reference field not seem elsewhere during the current surveys. notes, photographs, and other metadata to individ- The alluvial lowlands surrounding these uplifts ual collection sites. The site numbers correspond to have been populated for many centuries, and their those on the map in Fig. 11. hydrological systems consequently subjected to ex- tensive alteration for rice cultivation. This trend was Site 1 Cambodia, Koh Kong Prov., Cardamom excerbated during the years of gover- Mountains, O An Dart River, at high- nance, when extensive systems of weirs and canals way bridge ~73 km SE of Koh Kong, 27 m were constructed on the Mekong Basin side of the [90 ft], 11°16'38''N, 103°19'47''E, water Cardamom uplift (Himel 2007), in many cases link- temp. 26°C, 30 August 2015, 11:45–13:00 ing formerly separated river systems. As such, the hrs, CL 6015. Smoothly flowing amber-water aquatic Heteroptera biota of the Cambodian low- stream in sandy bed, surrounded by disturbed lands consists of species that have been able to adapt lowland evergreen rainforest. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

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Fig. 11. Map of aquatic Heteroptera collecting sites in southwestern Cambodia, plotted against vegetation classes. Dark green areas indicate semi-deciduous or evergreen broadleaf forests; pale green areas indicate deciduous diptero- carp forest; tan areas indicate cultivated lowlands; pale blue areas indicate wetlands.

Site 2 Cambodia, Koh Kong Prov., Cardamom 11°36'13''N, 103°29'34''E, water temp. Mountains, shaded forest streamlet on road 25.5°C, 31 August 2015, 10:00–10:15 hrs, to Thmar Bang village, 420 m [1375 ft], CL 6018. Large, swift mountain river with 11°36'14''N, 103°15'38''E, water temp. banks shaded by low elevation evergreen 26°C, 30 August 2015, 16:45–17:30 hrs, rainforest. CL 6016. Rocky first-order stream densely shaded by dwarf evergreen rainforest forest Site 5 Cambodia, Koh Kong Prov., ­Cardamom on sandstone. Mountains, ponds and ditches at ­Thmar Daun Peov village, 192 m [630 ft], Site 3 Cambodia, Koh Kong Prov., Cardamom 11°37'43''N, 103°31'46''E, water temp. Mountains, cascading stream in sandstone 28°C, 31 August 2015, 11:45–14:00 hrs, CL bed on road to Thmar Bang village, 355 m 6019. Artificial ponds and ditches set amid [1165 ft], 11°35'26''N, 103°13'50''E, water village fields, mostly unshaded. temp. 26°C, 30 August 2015, 17:45–18:30 hrs, CL 6017. Rocky first-order upland Site 6 Cambodia, Koh Kong Prov., Cardamom stream dropping through bed of sandstone Mountains, Toeuk Noeng River, 9 km SSE of plates, partially shaded by dwarf evergreen Thmar Bang village crossroads, 165 m [550 rainforest forest on sandstone (Fig. 7). ft], 11°37'33''N, 103°28'51''E, water temp. 26°C, 31 August 2015, 14:45–16:00 hrs, Site 4 Cambodia, Koh Kong Prov., Cardamom CL 6020. Moderately large, swiftly flowing Mountains, Arang River, 152 m [500 ft], river with alternating deep pools and rapids Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 97

over exposures of sandstone bedrock, banks forest, ~3 km NW of Chambok village, shaded by montane evergreen rainforest on 95 m [315 ft], 12°24'19''N, 104°06'01''E, sandstone. water temp. 28.5°C, 21 May 2016, 09:30– 10:30 hrs, CL 6033. Small stream in sandy Site 7 Cambodia, Koh Kong Prov., Cardamom bed with alternating shallow riffles and Mountains, stream ~31 km NE of Koh deeper pools, partially shaded by semi- Kong on road to Pursat, 310 m [1020 ft], decidous mesic forest, bamboo and second- 11°41'43''N, 103°06'57''E, water temp. ary thorn scrub. 26°C, 1 September 2015, 10:00–10:40 hrs, CL 6021. Smoothly flowing, moderate sized Site 13 Cambodia, Kampong Speu Prov., Sva Slab stream with banks shaded by montane ever- river at rapids in igneous bedrock, ~4.5 km green rainforest. NW of Chambok village, 95 m [310 ft], 12°24'45''N, 104°05'025''E, water temp. Site 8 Cambodia, Koh Kong Prov., Cardamom 30.5°C, 21 May 2016, 11:00–12:15 hrs, Mountains, stream in sandstone bed cross- CL 6034. Large premontane river with deep ing pine barren on road from Koh Kong pools, traversing sill of diabase bedrock with to Pursat, 405 m [1330 ft], 11°49'29''N, scattered water-filled potholes, banks par- 103°04'14''E, water temp. 25°C, 1 Septem- tially shaded by semi-decidous mesic forest, ber 2015, 11:50–12:20 hrs, CL 6022. Swiftly bamboo and secondary thorn scrub. flowing, moderate-sized stream emerging from montane evergreen broadleaf forest and Site 14 Cambodia, Kampot Prov., Elephant Moun- traversing open, grassy pine barren with scat- tains, Bokor Plateau, rocky stream in wet tered Pinus merkusii. upland forest, ~20 km from Hwy 3 on road to Bokor resort, 965 m [3165 ft], Site 9 Cambodia, Koh Kong Prov., Cardamom 10°37'33''N, 104°04'10''E, water temp. Mountains, ponded stream on road from 22°C, 22 May 2016, 08:00–09:00 hrs, CL Koh Kong to Pursat, 540 m [1770 ft], 6035. Small stream heavily shaded by dense 12°00'58''N, 103°10'47''E, water temp. evergreen montane rainforest. 24.5°C, 1 September 2015, 13:45–14:30 hrs, CL 6023. Stream emerging from montane Site 15 Cambodia, Kampot Prov., Bokor Plateau, evergreen rainforest and forming large, un- pond in wet upland forest, ~22 km from shaded pond on upstream side of road, with Hwy 3 on road to Bokor resort, 985 m swift outlet through road culvert. [3240 ft], 10°37'42''N, 104°03'14''E, wa- ter temp. 22°C, 22 May 2016, 09:30–10:15 Site 10 Cambodia, Pursat Prov., Cardamom Moun- hrs, CL 6036. Deep pond with grassy mar- tains, O Sarb Morth stream (= Sap Mat gins, set amid dense evergreen montane stream), N of Vealveang village on road rainforest (Fig. 10). to Pursat, 230 m [760 ft], 12°18'31''N, 103°06'36''E, water temp. 27°C, 2 Sep- Site 16 Cambodia, Kampot Prov., Elephant Moun- tember 2015, 08:00–09:30 hrs, CL 6024. tains, Bokor Plateau, stream in sandstone Shallow, moderately swift stream in gravel bed, ~15 km from Hwy 3 on road to Bokor bed with spring-fed side channel, partially resort, 815 m [2675 ft], 10°37'48''N, shaded by disturbed evergreen rainforest and 104°05'11''E, water temp. 23°C, 22 May secondary regrowth. 2016, 11:00–12:15 hrs, CL 6037. Steeply dropping stream in bed of horizontal sand- Site 11 Cambodia, Prov., Bori stone strata, with alternating pools and small Bo River at Hwy 4 bridge, 20 m [70 ft], trickling cascades, partially shaded by ever- 12°23'04''N, 104°29'11''E, water temp. green montane rainforest. 29°C, 2 September 2015, 15:00–15:45 hrs, CL 6025. Broad, shallow, unshaded Site 17 Cambodia, Sihanoukville Prov., Carda- river in sandy bed, bordered by secondary mom Mountains, river in sandstone bed at vegetation. Thmor Roung recreation area, 65 m [210 ft], 11°11'05''N, 103°56'00''E, water temp. Site 12 Cambodia, Kampong Speu Prov., small per- 28.5°C, 24 May 2016, 10:00–11:30 hrs, CL ennial stream in disturbed semi-deciduous 6038. Large premontane river flowing over

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98 Tijdschrift voor Entomologie, volume 160, 2017

sandstone bedrock and gravel, with alternat- and crossroads, 75 m [255 ft], 11°38'57''N, ing deep pools and shallow rapids, bordered 104°11'46''E, water temp. 30°C, 29 May by disturbed low elevation evergreen rain- 2016, 11:00–11:30 hrs, CL 6044. Moder- forest on sandstone ately flowing stream in gravel bed with alter- nating deep pools and shallow riffles, shaded Site 18 Cambodia, Sihanoukville Prov., Cardamom along its margins by bamboo and secondary Mountains, rocky stream crossing Hwy 4, thorn scrub (Fig. 9). ~6 mi. SW of pass at Pich Nil, 45 m [155 ft], 11°11'07''N, 104°01'52''E, water temp. Site 24 Cambodia, Kampong Speu Prov., outflow 28.5°C, 24 May 2016, 12:00–13:00 hrs, CL stream from diked wetlands on Hwy 4, 10 6039. Moderately large, swift stream in bed km E of Krong , 35 m [115 ft], of boulders, rocks and gravel, bordered by 11°28'40''N, 104°35'56''E, water temp. disturbed secondary vegetation. 31°C, 29 May 2016, 12:45–13:30 hrs, CL 6045. Moderately swift stream in unshaded Site 19 Cambodia, Kampong Speu Prov., hot artificial channel draining extensive diked springs and outflow creek 9.5 km W of wetlands. village and crossroads, 105 m [340 ft], 11°43'26''N, 104°03'19''E, water Site 25 Cambodia, Kampong Speu Prov., Kirirom temp. 45°C (spring head), 37°C (outflow Plateau, Tachot Stream, crossing at first creek), 28 May 2016, 07:15–07:40 hrs, CL bridge on road up to summit, 315 m [1035 6040. Unshaded thermal spring outflows ft], 11°32'42''N, 104°55'23''E, water temp. on valley floor surrounded by open grassy 27°C, 4 June 2016, 08:45–09:20 hrs, CL pastures. Note: no aquatic Heteropera were 6046. Small, slowly flowing stream with taken at this unusual site. deep pools and shallow riffles, surrounded by recently cleared gardens and second growth. Site 20 Cambodia, Kampong Speu Prov., Carda- mom Mountains, trib. to Thom River, 1 km Site 26 Cambodia, Kampong Speu Prov., Kirirom E of Rolak Kong Cheung village at forest Plateau, Tasek Stream, crossing at second ranger station, 145 m [474 ft], 11°43'30''N, bridge on road up to summit, 640 m [2095 103°50'54''E, water temp. 28.5°C, 28 ft], 11°19'23''N, 104°04'59''E, water temp. May 2016, 09:00–1300 hrs, 29 May 2016, 25°C, 4 June 2016, 9:30–10:30 hrs, CL 08:00–09:00 hrs, CL 6041. Moderate sized 6047. Moderately swift stream in gravel premontane foreland stream in bed of rocks bed, heavily shaded by broadleaf evergreen and gravel, partially shaded by semi-decidu- gallery forest corridor within upland pine ous mesic forest (Fig. 8). forest dominated by Pinus merkusii. Site 21 Cambodia, Kampong Speu Prov., Carda- Site 27 Cambodia, Kampong Speu Prov., Kirirom mom Mountains, Thom River, 2 km W of Plateau, roadside reservoir in pine forest, 690 Rolak Kong Cheung village, 185 m [610 m [2260 ft], 11°20'01''N, 104°03'08''E, ft], 11°43'15''N, 103°49'21''E, water temp. water temp. 32°C, 4 June 2016, 10:45– 28.5°C, 28 May 2016, 14:00–15:00 hrs, CL 11:30 hrs, CL 6048. Open reservoir with 6042. Moderately large, swift premontane grassy margins surrounded by upland pine river with extensive overflow channels, heav- forest dominated by Pinus merkusii. ily shaded by evergreen gallery forest. All species listed in the following taxonomic section Site 22 Cambodia, Kampong Speu Prov., rocky represent new records for the country of Cambodia stream 7 km E of Rolak Kong Cheung village, unless otherwise noted. 135 m [440 ft], 11°42'43''N, 103°53'55''E, The following abbreviations are used for specimen water temp. 28.5°C, 29 May 2016, 09:00– depositories: 09:45 hrs, CL 6043. Slowly flowing stream in gravel bed with alternating deep pools and shallow riffles, shaded along its margins by BPBM Bernice P. Bishop Museum, Honolulu, bamboo and secondary thorn scrub. Hawaii, USA USNM United States National Museum of Site 23 Cambodia, Kampong Speu Prov., stream in ­Natural History, Smithsonian Institution, gravel bed 9 km E of Aoral District village Washington, DC, USA Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 99

Taxonomy D.A. Polhemus (BPBM); 6 wingless males, 6 wing- In the species treatments below, only abbreviated less females, Cardamom Mountains, Toeuk Noeng locality data is provided. For complete data regard- River, 9 km SSE of Thmar Bang village crossroads, ing any particular record, the reader is referred to 165 m [550 ft], 11°37'33''N, 103°28'51''E, water the preceding list of sampling localities. Complete temp. 26°C, 31 August 2015, 14:45–16:00 hrs, CL locality data for comparative Vietnamese localities 6020, D.A. Polhemus (BPBM). referenced in the text may be found in Appendix 2. Description Infraorder Gerromorpha Apterous male (Fig. 14). Body length 3.60 mm; max- Family Gerridae imum width (across thorax) 1.25 mm. Subfamily Cylindrostethinae Matsuda Color. Black Russet brown with limited dark brown to black markings on pronotum, mesonotum, dorsal Cylindrostethus costalis Schmidt abdomen, pleurae and venter (Fig. 14), and patches Cylindrostethus costalis Schmidt, 1915: 364. of silvery setae present on acetabulae and pleurae. Head russet brown with a faintly indicated V-shaped Material examined. Cambodia, Kampong Speu Prov.: black mark posteromedially; eyes dark red; tylus 1 winged male, 4 winged females, nr. Chambok, CL 6033; and antennal tubercles dark, bearing patches of sil- 2 winged males, 3 winged females, nr. Rolak, CL 6041; very setae; antennae with segment I medium brown, 1 winged male, 1 winged female, nr. ­Rolak, CL 6042; segments II–IV darker brown; rostrum yellowish- 1 winged female, nr. Rolak, CL 6043; 2 winged females, brown, with a ventromedial line and apex black. Pro- nr. Aoral, CL 6044; 1 winged male, Kirirom, CL 6047. notum russet brown, with a pair (1 + 1) of irregularly Ecological notes. This large, black-colored gerrid elongate dark patches to either side of longitudinal ­species was common on the lowland streams of midline, these patches initiating at anterior prono- . It seems to be an adapt- tal margin, tapering posteriorly, not quite attaining able generalist which can tolerate a modest degree of posterior pronotal margin (Fig. 14); propleura with habitat alteration and degraded water quality. narrow, weakly indicated longitudinal dark stripe centrally, bearing small patches of silvery setae be- Subfamily Eotrechinae Matsuda low eyes and on fore acetabula. Mesonotum russet brown, with a pair (1 + 1) of irregularly elongate Amemboa cambodiana n. sp. dark patches to either side of longitudinal midline, Figs 14–16, 19–24 these patches extending posteriorly for only half the mesonotal length (Fig. 14); mesopleuron with a Type material. Holotype, wingless male, Cambodia, strongly developed longitudinal stripe running from Kampot Prov., Elephant Mountains, Bokor Plateau, anterior margin to near metanotal suture, inner por- stream in sandstone bed, ~15 km from Hwy 3 on tion of this dark stripe bearing band of silvery se- road to Bokor resort, 815 m [2675 ft], 10°37'48''N, tae; mesoacetabula dark, bearing prominent patch 104°05'11''E, water temp. 23°C, 22 May 2016, of silvery setae. Metanotum broadly dark centrally 11:00–12:15 hrs, CL 6037, D.A. Polhemus and across anterior margin, russet brown laterally, (USNM). Paratypes: Cambodia, Kampot Prov., 9 bearing scattered very short, recumbent gold setae winged males, 2 winged females, 10 wingless males, on anterior half, these setae also extending onto ad- 10 wingless females, same data as holotype (USNM, jacent inner angles of metapleuron. Legs medium BPBM); 6 winged males, 6 winged females, 2 wing- brown, tarsi black. Abdominal tergites dark brown, less females, Elephant Mountains, Bokor Plateau, with central portions of tergites VI–VIII russet rocky stream in wet upland forest, ~20 km from brown, connexiva dark russet brown; both abdomi- Hwy 3 on road to Bokor resort, 965 m [3165 ft], nal tergites and connexiva bearing scattered very 10°37'33''N, 104°04'10''E, water temp. 22°C, 22 short, recumbent gold setae. Ventral surface yellow- May 2016, CL 6035, D.A. Polhemus (BPBM); Kam- ish-brown, posteromedial portion of mesosternum pong Chhnang Prov.: 10 wingless males, 6 wingless and longitudinal midline of abdomen suffused with females, Bori Bo River at Hwy 4 bridge, 20 m [70 darker brown. ft], 12°23'04''N, 104°29'11''E, water temp. 29°C, 2 Structural characteristics. Head — Width/length = September 2015, 15:00–15:45 hrs, CL 6025, D.A. 0.85/0.70, eye width 0.25, interocular width 0.50; Polhemus (BPBM). Koh Kong Prov.: 1 wingless lengths of antennal segments I–IV = 0.75, 0.70, male, Cardamom Mountains, cascading stream in 0.80, 1.05 respectively; rostrum length 1.45, extend- sandstone bed on road to Thmar Bang village, 355 m ing on mesosternum. [1165 ft], 11°35'26''N, 103°13'50''E, water temp. Pronotum — Width/length = 0.90/0.50; mesono- 26°C, 30 August 2015, 17:45–18:30 hrs, CL 6017, tum length 1.15; metanotum length 0.25. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

100 Tijdschrift voor Entomologie, volume 160, 2017

Figs 12–16. Amemboa species, dorsal habitus, appendages omitted. Figs 12, 13. A. burmensis, paratype specimens from Burma, Shingbwiyang. 12. Apterous male. 13. Apterous female. Figs 14–16. A. cambodiana, n. sp., specimens from Cambodia, Bokor Plateau, CL 6037. 14. Apterous male. 15. Apterous female.Downloaded 16. Macropterous from Brill.com10/07/2021 male. 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 101

Figs 17–19. Amemboa species, male right fore femur, dorsal view. 17. A. kumari, paratype specimen from India, Karnataka, Mudigere. 18. A. burmensis, paratype specimen from Burma, Shingbwiyang. 19. A. cambodiana, n. sp., specimen from Cambodia, Kampot Prov., Bokor Plateau, CL 6037. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

102 Tijdschrift voor Entomologie, volume 160, 2017

Figs 20–24. Amemboa cambodiana n. sp., male genitalia, specimen from Cambodia, Kampot Prov., Bokor Plateau, CL 6037. 20. Proctiger, dorsal view. 21. Pygophore, ventral view. 22. Pygophore, left ventrolateral oblique view, showing form of posterior projection. 23. Endosoma, lateral view. 24. Endosoma, dorsal view.

Legs — Fore femur slightly incrassate, bearing 2 middle femur/tibia/tarsal I/tarsal II = 3.10/2.30/ tufts of stiff black setae on distal half, these tufts of 0.90/0.45; hind femur/tibia/tarsal I/tarsal II = roughly equal size, separated by a gap about 2× the 3.20/1.20/0.50/0.35. width of each tuft (Fig. 19); fore tibia very slightly Male genitalia — Pygophore roughly triangular, sinuate on basal half, bearing a fringe of short, dense bearing a small, bulb-like apical process (Fig. 20). black setae along inner margin on basal two-thirds Proctiger with lateral process elongate, slightly ex- (Fig. 19); lengths of leg segments as follows: fore ceeding posterior margin of abdominal tergite VIII, femur/tibia/tarsal I/tarsal II/ = 1.35/1.30/0.20/0.30; with distal sections gently curving and slightly Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 103 convergent when viewed dorsally (Fig. 21), slightly between the two species, with A. burmensis bearing a sinuate and oriented horizontally with inwardly basal patch of dark setae that is lacking in A. cambo­ hooked apices in oblique lateral view (Fig. 22); diana, a more elongate sub-distal tuft near the center endosoma with internal sclerites asymmetrical of the femur, and a denser, less pointed tuft distally (Figs 23, 24). on the femur (compare Figs 18 and 19); c) the male Apterous female (Fig. 15). Similar to wingless male in fore tibia in A. burmensis is more sinuate and bears general structure and coloration with following ex- a more prominent fringe of short, dense, dark setae ceptions: body form larger and more robust, length centrally in comparison to A. cambodiana (compare 4.30 mm; maximum width across thorax 1.60 mm. Figs 18 and 19); and d) in A. cambodiana the pro- Fore legs simple, slender, lacking setal tufts or other cesses on the male proctiger are slightly hooked at modifications. Abdominal tergites VII–IX angled the apices in oblique lateral view (Fig. 22), whereas downward at approximately 45°, cupped within in A. burmensis they are not. Both species are similar concavity formed by upraised margins of abdominal in having a small, bulb-like process at the apex of the ventrite VI. male pygophore (Fig. 20), but in A. cambodiana this Macropterous male (Fig. 16). Similar to apterous process is slightly more elongate. male in general structure and coloration, with fol- Amemboa cambodiana also bears certain morpho- lowing exceptions: body length inclusive of wings logical similarities to A. kumari J. Polhemus & An- 4.80–4.90 mm, exclusive of wings 3.90 mm, maxi- dersen (1984), described from the Western Ghats of mum width across humeral angles of pronotum 1.30 India. However, an examination of a wingless male mm; pronotum prolonged posteriorly, length along and wingless female of the latter species from “S. longitudinal midline 1.50 mm, anterior lobe russet India, Karnataka, Mudigere area, c. 900 m, 2–10. brown, posterior lobe dark blackish brown, a pair xi.1977, Zool. Mus. Copenhagen Exp.”, both para- (1 + 1) of irregular black stripes running length of types determined by N.M. Andersen, reveals clear pronotum to either side of longitudinal midline, hu- differences between the two species. In particular, meral angles and posterior margin also blackish, sur- the more sub-distal setal tuft on the male foreleg in face of posterior lobe set with numerous fine, recum- A. kumari is small and acuminate, whereas in A. bent golden setae; wings very long, exceeding apex of cambodiana it is broad and truncate (compare abdomen, blackish brown, veins set with very short, Figs 17, 19). In addition, the processes on the male recumbent, golden setae (Fig. 16), venation well de- pygophore are sinuate and apically acute in A. ku­ marcated, defining 5 closed cells extending into pos- mari when viewed ventrally, whereas in A. cambodi­ terior half of wing. ana they are gently curved and their apices broadly Macropterous female. Similar to winged male in gen- rounded (Figs 21, 22); when viewed posteriorly, eral structure and coloration, with following excep- these processes are narrow, slightly sinuate, and acu- tions: body length inclusive of wings 5.25 mm, ex- minate apically in A. kumari, vs broad and apically clusive of wings 4.40 mm, maximum width across blunt in A. cambodiana. The dorsal color patterns humeral angles of pronotum 1.50 mm. also differ, with A. kumari having a more orange– Etymology. The name “cambodiana” refers to the brown ground color and the paired thoracic stripes country of origin for this new species. on the metanotum far more extensively developed, Comparative notes. This new species keys to Amem­ whereas these stripes become posteriorly obscure in boa burmensis in Polhemus & Andersen (1984), and A. cambodiana (Figs 14, 15). Finally, the metanotum is similar to that species in many respects. However, in A. kumari is dark with paired pale spots to either a comparison of the Cambodian specimens in hand side of midline, vs uniformly dark brown to blackish to two wingless male and two wingless female para- and lacking paired pale spots in A. cambodiana. type specimens of A. burmensis from Shingbwiyang, Although the females of both A. kumari and A. Burma indicates that they in fact represent a separate cambodiana are of similar size (4.3 mm), the male of species. The two taxa differ as follows: a) The ground A. kumari is noticably smaller than that of A. cam­ color of A. burmensis is yellowish brown, vs russet bodiana, having a body length 3.4 mm; sexual di- brown in A. cambodiana, and is overlain with dark morphism body size is thus more pronounced in A. markings on the dorsum that are far more extensive kumari, which is very evident when the two species and broader in width than those of A. cambodiana, are compared side by side. with dark stripes to either side of the longitidinal Ecological notes. Amemboa cambodiana is common midline extending the entire length of the mesono- along sandstone-bedded streams in the Cardamom tum, vs extending only half the length in A. cambo­ Mountains and adjacent plateaus, where it occurs diana, and the head bearing a prominent V-shaped along the margins of pools formed amid horizon- mark on the vertex that is absent in A. cambodiana tal sandstone ledges (Fig. 7). Although three other (compare Figs 12, 13 to Figs 14, 15); b) the arrange- species of Amemboa were collected in Cambodia ment of setal tufts on the male fore femur differs during the current surveys, in only one case was Downloaded from Brill.com10/07/2021 06:11:13PM via free access

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A. cambodiana taken syntopically with any of them, bed of a stream that descended from the flanks of this being its co-occurrence with A. cristata on sand- the Bokor Plateau. It was also seen in lesser num- bars at the Bori Bo River in Kampong Chhnang bers on sandstone-bedded streams in the Cardamom Province. Mountains.

Amemboa cristata J. Polhemus & Andersen Subfamily Gerrinae Leach Amemboa cristata J. Polhemus & Andersen, 1984: 95. Limnogonus fossarum fossarum (Fabricius) Cimex fossarum Fabricius, 1775: 727. Material examined. Cambodia, Kampong Chhnang Gerris fossarum: Fabricius, 1794: 188. Prov.: 1 winged female, 1 wingless female, Bori Bo, CL Hydrometra fossarum: Fabricius, 1803: 258. 6025. Gerris discolor Stål, 1859: 265; syn. by Lundblad, Ecological notes. This species, which can be recog- 1933: 377. nized by the acuminate tufts of dark hairs at the pos- Limnogonus fossarum: Stål, 1868: 133. terior margin of the female abdomen, was taken as a Limnogonus discolor: Stål, 1868: 133. few scattered individuals on sandbars along the low- Tenagogonus nymphae Esaki, 1925: 58; syn. by Esaki, land Bori Bo River which drains the Mekong River 1926: 181. side of the Cardamom uplift. Tenagogonus okinawanus Esaki, 1925: 59; syn. by ­Andersen, 1975: 30. Amemboa javanica Lundblad Limnogonus okinawanus: Lundblad, 1933: 371. Amemboa javanica Lundblad, 1933: 405. Limnogonus fossarum fossarum: Andersen, 1975: 30.

Material examined. Cambodia, Kampong Speu Prov.: 2 Material examined. Cambodia, Kampong Speu Prov.: 2 winged males, 1 wingless male, 1 wingless female, nr. Ro- wingless females, Kirirom, CL 6046. Koh Kong Prov.: 1 lak, CL 6041. winged male, nr. Thmar Bang, CL 6016. Ecological notes. Amemboa javanica was found as Discussion. The nominate subspecies of L. fossarum scattered individuals along the margins of pools which occurs in Cambodia is widely distributed along a rocky stream at Rolak village (Fig. 8), in the from India and Ceylon eastward through Indochina premontane foreland near the northeastern margin to China, Japan, the Philippines, the Malay Penin- of the Cardamom Mountains. sula, Sumatra and Borneo (Andersen 1975).

Amemboa speciosa J. Polhemus & Andersen Limnogonus hungerfordi Andersen Amemboa speciosa J. Polhemus & Andersen, 1984: 94. Limonogonus hungerfordi Andersen, 1975: 46.

Material examined. Cambodia, Koh Kong Prov.: 1 Material examined. Cambodia, Pursat Prov.: 1 wingless winged male, Koh Kong–Pursat, CL 6023. male, 1 wingless female, nr. Vealveang, CL 6024. Discussion. As noted by Andersen (1975), this spe- Ecological notes. A pair of specimens representing cies is externally all but indistinguishable from this species was splashed from a half-submerged log (Montrousier), with definitive identifi- lying in the middle of a deep pool on a quiet, shaded, L. luctuosus cation reliant upon dissection of the male genitalia spring-fed tributary backwater to the O Sarb Morth and examination of the posterior margin of the male stream just north of Vealveang. dorsal vesical plate. The male genitalia of the Cam- bodian specimen in hand show that the shape of this Onychotrechus esakii Andersen plate falls within the range of variation illustrated for Onychotrechus esakii Andersen, 1980: 127. L. hungerfordi by Andersen (1975, Figs 120–122). As noted by Cheng et al. (2001), although widely Material examined. Cambodia, Kampot Prov.: 5 wingless distributed across a range encompassing northeast- males, 4 wingless females, Bokor Plateau, CL 6037. Koh ern Australia, New Guinea, the Malay Archipelago, Kong Prov.: 1 wingless male, nr. Thmar Bang, CL 6017; 4 the Malay Peninsula, the Philippines and Taiwan wingless males, Touek Noeng, CL 6020. (Andersen 1975), this is a rare species in continen- Ecological notes. This species is the most widespread tal , and the current record is the first Onychotrechus in Southeast Asia (Andersen 1980), for Cambodia, and apparently for Indochina as a and was abundant on wet sandstone plates in the whole.

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Limnogonus nitidus (Mayr) CL 6048. Kampot Prov.: 1 winged male, 1 winged female, Hydrometra nitida Mayr, 1865: 443. 2 wingless males, 1 wingless female, Bokor Plateau, CL Gerris nitida: Distant, 1904: 178. 6036. Limnogonus nitidus: Kirkaldy, 1908: 21. Ecological notes. This is a widespread species on len- tic habitats throughout Southeast Asia. Material examined. Cambodia, Sihanoukville Prov.: 1 winged male, nr. Pich Nil, CL 6039. Pursat Prov.: 1 winged male, nr. Vealveang, CL 6024. Subfamily Halobatinae Bianchi Discussion. This species is widespread, with range ex- tending from the Maldive Islands through Ceylon, Metrocoris nigrofascioides Chen & Nieser India, Indochina, the Malay Peninsula, Sumatra, Metrocoris nigrofascioides Chen & Nieser, 1993: 16. Java and Borneo (Andersen 1975). Material examined. Cambodia, Kampong Speu Prov.: 2 Limnometra matsudai (Miyamoto) wingless females, Sva Slab, CL 6034. Koh Kong Prov.: 2 Tenagogonus (Limnometra) matsudai Miyamoto, 1967: winged females, 4 wingless males, 1 wingless female, nr. 223. Thmar Bang, CL 6016; 3 winged males, 1 winged female, Limnometra matsudai: Andersen, 1995: 118. nr. Thmar Bang, CL 6017; 2 wingless males, 2 wingless fe- males, Touek Noeng, CL 6020; 1 wingless male, 4 wingless Material examined. Cambodia, Kampot Prov.: 1 wingless females, Koh Kong–Pursat, CL 6023. female, Bokor Plateau, CL 6035; 2 winged males, 4 winged Ecological notes. This species occurs as scattered pop- females, 1 wingless male, 4 wingless females, Bokor Plateau, ulations at intermediate elevations in the Cardamom CL 6037. Koh Kong Prov.: 2 wingless males, 5 wingless fe- Mountains (Tran & Polhemus 2017). males, nr. Thmar Bang, CL 6016; 2 wingless males, Toeuk Noeng, CL 6020. Pursat Prov.: 1 winged female, 1 wing- Metrocoris tenuicornis Esaki less female, nr. Vealveang, CL 6024. Sihanoukville Prov.: 1 Metrocoris tenuicornis Esaki 1926: 125. winged male, 2 wingless females, Thmar Roung, CL 6038. Ecological notes. This is a common species along first- and second-order upland streams draining the Material examined. Cambodia, Koh Kong Prov.: 2 Cardamom Mountains, Kirirom Plateau, and Bokor wingless males, 3 wingless females, Koh Kong–Pursat, Plateau. In these uplifts it was often one of the only CL 6021. species encountered on small headwater streamlets at Ecological notes. This species is widely distributed elevations above 500 m. on lowland forest streams throughout Southeast Asia, but so far encountered in Cambodia only on Limnometra octopunctata Hungerford a single stream in the mountains behind Koh Kong. Limnometra octopunctata Hungerford, 1955: 67. Geographic variation in paramere shape suggests that more than a single species may be involved Material examined. Cambodia, Sihanoukville Prov.: 1 across its wide range in Indochina (Tran & Polhemus winged female, Thmar Roung, CL 6038. 2017). Ecological notes. Limnometra octopunctata appears to be uncommon and localized in southwestern Cam- Ventidius (Ventidius) distanti Paiva bodia, being taken only at a single locality at Thmar Ventidius distanti Paiva, 1918: 25. Roung where a sandstone-bedded river exits the Ventidius modulatus Lundblad, 1933: 339; syn. by mountain foothills onto the coastal plain. Chen, Nieser & Zettel, 2005: 404. Ventidius chinai Hungerford & Matsuda, 1960: 331; Neogerris parvula (Stål) syn. by Chen & Zettel, 1998: 170. Gerris parvula Stål, 1859: 265. Ventidius pubescens Cheng, 1965: 160; syn. by Chen & Limnogonus parvulus: Stål, 1868: 133. Zettel, 1998: 170. Gerris tristan Kirkaldy, 1899: 88; syn. by Lundblad, 1933: 385. Material examined. Cambodia, Kampong Chhnang Gerris ysolt Breddin, 1905: 130; syn. by Lundblad, Prov.: 3 winged females, 3 wingless males, 6 wingless fe- 1933: 385. males, Bori Bo, CL 6025. Kampong Speu Prov.: 2 winged Neogerris parvulus: Andersen, 1975: 86. females, nr. Rolak, CL 6043; 3 winged females, nr. Aoral, CL 6044; 6 wingless males, 15 wingless females, nr. Krong Material examined. Cambodia, Kampong Speu Prov.: 1 Chbar Mon, CL 6045. Koh Kong Prov.: 1 winged male, winged female, Sva Slab, CL 6034; 1 winged female, nr. 2 winged females, 1 wingless male, Thmar Daun Peov, Krong Chbar Mon, CL 6045; 1 wingless female, Kirirom, CL 6019; 9 wingless males, 12 wingless females, Koh

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­Kong–Pursat, CL 6021. Pursat Prov.: 1 wingless male, 1 were taken on upland ponds (Fig. 4), and on calm ­wingless female, nr. Vealveang, CL 6024. Sihanoukville pools or backwaters of streams in the premontane Prov., 3 winged males, 10 wingless females, nr. Pich Nil, foreland of the Cardamom Mountains and the Kiri- CL 6039. rom Plateau. Discussion. This species was originally described from the He-Ho River gorge in Yawngshwe State, Lathriobates johorensis (J. Polhemus & D. Polhemus) Burma. When preparing their revision of Ventidius, Cryptobates johorensis J. Polhemus & D. Polhemus, Chen & Zettel (1998) did not examine the types of 1995: 102. this species, but noted that it had close similarities to Lathriobates johorensis: J. Polhemus, 2004: 212. the widespread V. modulatus Lundblad. It was sub- sequently determined that V. modulatus is in fact a junior synonym of V. distanti (Chen et al. 2005). Material examined. Cambodia, Kampong Speu Prov.: 1 Ecological notes. In Cambodia, this species is com- winged female, 2 wingless females, nr. Chambok, CL 6033. mon and widespread, being found on the smoothly Sihanoukville Prov.: 1 winged female, Thmar Roung, CL flowing streams of the premontane foreland below 6038; 1 winged male, 2 winged females, 1 wingless female, the Cardamom Mountains, sometimes in large nr. Pich Nil, CL 6039. schools, and also ranging upward into the mountains Ecological notes. This species occasionally co-occurs to at least 640 m elevation. with Gnomobates kuiterti, but is larger in size and more greyish in overall coloration. It was originally Ventidius (Ventidioides) karen Lansbury described from Johor, in the southern Malay Penin- Ventidius (Ventidiopsis) karen Lansbury, 1988: 61. sula, with all previous records coming from localities south of the Isthmus of Kra; as such, the new Cam- bodian records represent a northern range extension Material examined. Cambodia, Kampong Speu Prov.: into Indochina. 1 winged male, Kirirom, CL 6047. Sihanoukville Prov.: 2 winged females, 2 wingless males, Thmar Roung, Naboandelus signatus Distant CL 6038. Naboandelus signatus Distant, 1910: 152. Discussion. The dorsal coloration and male genitalic structures of the Cambodian material match the re- description in Chen & Zettel (1998). This species Material examined. Cambodia, Kampong Chhnang appears to be of relatively localized occurrence in Prov.: 2 winged males, 2 wingless males, 2 wingless ­females, southwestern Cambodia. Bori Bo, CL 6025. Ecological notes. A widespread species ranging from Ceylon through India and Thailand to Cambodia, Subfamily Trepobatinae Matsuda N. signatus was found on open waters along the mar- gins of the shallow, sandy Bori Bo River which drains Gnomobates kuiterti (Hungerford & Matsuda) to the Tonle Sap. Cryptobates kuiterti Hungerford & Matsuda, 1958: 246. Gnomobates kuiterti: J. Polhemus & D. Polhemus, Subfamily Ptilomerinae Bianchi 1995: 108. Ptilomera hylactor Breddin Ptilomera hylactor Breddin, 1903: 148. Material examined. Cambodia, Kampong Speu Prov.: 1 winged male, nr. Chambok, CL 6033; 3 wingless females, nr. Rolak, CL 6043. Kampot Prov: 1 wingless male, 5 Material examined. Cambodia, Pursat Prov.: 2 wingless wingless females, Bokor Plateau, CL 6036. S­ ihanoukville males, 5 wingless females, nr. Vealveang, CL 6024. Prov.: 2 winged females, 1 wingless male, 1 wingless fe- Ecological notes. This species was encountered in male, nr. Pich Nil, CL 6039. southwestern Cambodia only on a single stream Discussion. With a body length of less than 3.0 mm, immediately outside Vealveang. Ptilomera hylactor this is the smallest species of Trepobatinae occurring is generally a species of larger, more open, gravel- in Cambodia. There is some intraspecific variation in bottomed rivers in comparison to P. tigrina, which color, with specimens from higher elevation on the prefers small to moderate-sized rocky upland streams. Bokor Plateau somewhat darker than those from the lowlands of Kampong Speu Province. Ptilomera tigrina Uhler Ecological notes. This species was described from ma- Ptilomera tigrina Uhler, 1860: 230. terial taken in Burma, and previously known from Ptilomera harpyia Schmidt,1926: 65; syn. by J. Pol- India and Thailand as well. In Cambodia individuals hemus, 1992: 439.

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Material examined. Cambodia, Kampong Speu Prov.: from New Guinea, Borneo and Sumatra (Polhemus 1 wingless female, Kirirom, CL 6046. Koh Kong Prov.: 1 & Karunaratne 1993), but the Cambodia records are winged female, 2 wingless males, 2 wingless females, nr. the first for mainland Southeast Asia. Thmar Bang, CL 6017; 1 wingless male, 1 wingless female, Arang River, CL 6018; 1 wingless male, 2 wingless females, Rhagadotarsus kraepelini Breddin Touek Noeng, CL 6020; 1 wingless male, 1 wingless fe- Rhagadotarsus kraepelini Breddin, 1905: 137. male, Koh Kong–Pursat, CL 6023. ­Sihanoukville Prov.: 2 wingless males, 2 wingless females, nr. Pich Nil, CL Material examined. Cambodia, Kampong Speu Prov.: 5 6039. wingless males, 6 wingless females, nr. Rolak, CL 6043. Ecological notes. This species was previously recorded from Cambodia by D. Polhemus (2001). Ptilomera ti­ grina is confined to rocky hill streams and iscommon ­ Discussion. This species has a very wide range, from in the interior Cardamom Mountains. It ­essentially Ceylon and India eastward through Southeast Asia replaces Cylindrostethus costalis as the large-sized, to Taiwan, Palau and New Guinea (Polhemus & stream-dwelling stream gerrid above 100 m eleva- Karunaratne 1993). Its presence in Cambodia was tion, and is never seen on the alluvial streams of the therefore to be expected. ­Cambodian Plain frequented by that latter species. The zone of sympatry for the two genera on the flanks Family Hebridae Amyot & Serville of the Kirirom Plateau lay in a zone between 45 and 315 m. The overall distribution of this species in Hebrus nieseri Zettel Southeast Asia was summarized and mapped by D. Hebrus nieseri Zettel, 2004: 544. Polhemus (2001), and further data for southern Thai- land were provided by Raruanysong et al. (2014). Material examined. Cambodia, Pursat Prov.: 1 winged male, nr. Vealveang, CL 6024. Rheumatogonus vietnamensis Zettel & Chen Discussion. The male genitalic structures and small, Rheumatogonus vietnamensis Zettel & Chen, 1996: triangular lateral tubercles on the frons match the il- 171. lustrations in Zettel (2004). The species was origi- nally described from specimens taken in northern Material examined. Cambodia, Sihanoukville Prov.: 3 Thailand, so the Cambodian record is a considerable winged males, 9 wingless males, 5 wingless females, nr. range extension. Pich Nil, CL 6039. Ecological notes. This species was originally de- scribed from Vietnam (Zettel & Chen 1996) and Hebrus cf. polysetosus Zettel subsequently recorded from southern Thailand by Hebrus polysetosus Zettel, 2004: 541. Raruanysong et al. (2014), and from several locali- ties in Cambodia by Zettel et al. (2017). During the Material examined. Cambodia, Kampong Speu Prov.: current surveys it was encountered only at a single 1 winged female, nr. Rolak, CL 6041. site, on a large, rocky stream below the Kirirom hy- Discussion. The one female specimen at hand from a droelectric plant. stream at Rolak village (Fig. 5) conforms to Zettel’s (2004) description of this species in regard to size (length 2.0 mm), blackish coloration with yellow Subfamily Rhagadotarsinae Lundblad legs, the presence of elongate setae on the head, and the shape of the scutellum. A definitive identifica- Rhagadotarsus borneensis J. Polhemus & tion, however, cannot be made in the absence of a Karunaratne male specimen, so the assignment of this specimen to Rhagadotarsus borneensis J. Polhemus & Karuna­ H. longisetosus must be considered provisional until ratne, 1993: 106. the Rolak specimen can be compared to females in the type series. This species was originally described Material examined. Cambodia, Kampong Speu Prov.: ; from specimens taken in Thailand and southern 1 winged female, nr. Rolak, CL 6041; 1 winged male, 1 Laos, so has a broad range within Indochina. winged female, nr. Rolak, CL 6042. Pursat Prov.: 1 winged male, 2 wingless males, 5 wingless females, nr. Vealveang, CL 6024. Family Hydrometridae Billberg Discussion. The series listed above key to this species on the basis of hind femoral length, and the pres- Hydrometra annamana Hungerford & Evans ence of long setae on antennal segments III and IV Hydrometra annamana Hungerford & Evans, 1934: in the female. This species was previously recorded 68.

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Material examined. Cambodia, Koh Kong Prov.: 1 wing- Hydrometra sumatrana Ruhoff, 1964: 32; syn. by J. less male, Koh Kong–Pursat, CL 6022. Polhemus & Riesen, 1986: 284. Discussion. This is a widespread east Asian species, with a range encompassing Japan, Formosa, China Material examined. Cambodia, Kampong Speu Prov.: 1 and Indochina. Hydrometra annamana was previous- winged male, 1 winged female, Sva Slab, CL 6034. Kam- ly recorded from Thailand and Vietnam (Polhemus pot Prov.: 1 winged male, 1 winged female, Bokor Plateau, & Polhemus 1995), and its presence in Cambodia is CL 6036. thus logical. Discussion. This species is broadly distributed in in- sular Southeast Asia, ranging from northern ­Australia Hydrometra gilloglyi J. Polhemus & D. Polhemus through the Malay Archipelago and the Philippines Hydrometra gilloglyi J. Polhemus & D. Polhemus, to Indochina and Hainan Island (­Polhemus & 1995: 20. ­Polhemus 1995; Tran et al. 2010).

Material examined. Cambodia, Kampong Speu Prov.: 2 Family Mesoveliidae Douglas & Scott winged males, nr. Chambok, CL 6033. Koh Kong Prov.: 1 wingless male, O An Dart, CL 6015. Pursat Prov.: Mesovelia horvathi Lundblad 4 winged females, 4 wingless males, nr. Vealveang, CL Mesovelia horvathi Lundblad, 1933: 190. 6024. Discussion. Hydrometra gilloglyi as currently inter- preted (Tran et al. 2010) has been previously record- Material examined. Cambodia, Kampong Chhnang ed from Vietnam, Thailand, northern Peninsular Prov.: 2 winged males, 1 winged female, 4 wingless fe- Malaysia, and Hainan Island. The new Cambodian males, Bori Bo, CL 6025. Kampong Speu Prov.: 2 winged records fill an obvious gap in the species’ geographic males, 1 wingless female, Sva Slab, CL 6034; 1 wingless range. female, nr. Krong Chbar Mon, CL 6045; 2 winged fe- males, 1 wingless female, Kirirom, CL 6046. Koh Kong Hydrometra jackzewskii Lundblad Prov.: 1 wingless male, O An Dart, CL 6015: 1 wingless Hydrometra jackzewskii Lundblad, 1933: 433. male, Thmar Don Peov, CL 6019. Pursat Prov.: 1 winged female, 1 wingless male, 1 wingless female,­ nr. Vealveang, CL 6024. Material examined. Cambodia, Kampong Speu Prov.: 2 Discussion. Mesovelia horvathi is a very widespread males, Kirirom, CL 6047. species, ranging from New Guinea and northern Discussion. This species was previously recorded Australia westward through the Malay Archipelago from Java, Sumatra and Burma (Polhemus & Pol- and the Philippines to Japan and Southeast Asia. Re- hemus 1995), and its discovery in Cambodia serves cords for Thailand and Vietnam were provided by to bridge this previously fragmented distributional Polhemus & Polhemus (2000), but the species was pattern. not previously known from Cambodia.

Hydrometra longicapitis Torre Bueno Mesovelia vittigera Horvath Hydrometra longicapitis Torre Bueno, 1927: 31. Mesovelia vittigera Horvath, 1895: 160.

Material examined. Cambodia, Kampong Speu Prov.: 2 Material examined. Cambodia, Pursat Prov.: 1 wingless females, Kirirom, CL 6047. Pursat Prov.: 1 winged female, male, nr. Vealveang, CL 6024. 2 brachypterous females, nr. Vealveang, CL 6024. Discussion. This is the most widespread Mesovelia Discussion. This species was previously known species in the Eastern Hemisphere, occurring from from Sumatra, Peninsular Malaysia, Thailand and Africa through Asia and eastward into the Pacific is- Borneo (Polhemus & Polhemus 1995), so its pres- lands as far as Guam. Despite this, it was not com- ence in Cambodia was to be expected. As with monly encountered during the current surveys, with Rhagovelia tebakang (see subsequent discussion M. horvathi being far more predominent on standing under that species), it has a range that spans the water habitats in the lowlands of Cambodia. South China Sea, indicating a disjunct Sundaland distribution. Family Veliidae Amyot & Serville Hydrometra orientalis Lundblad Subfamily Haloveliinae Esaki Hydrometra orientalis Lundblad, 1933: 430. Hydrometra insularis Hungerford & Evans, 1934: 76; Strongylovelia albopicta Zettel & Tran syn. by J. Polhemus & Riesen, 1986: 284. Strongylovleia albopicta Zettel & Tran, 2004: 80. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

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Material examined. Cambodia, Kampong Speu Prov.: larger body sizes, symmetrical male parameres, ab- 1 winged male, 2 wingless males, 11 wingless females, nr. sence of lateral projections on the male proctiger, ab- Rolak, CL 6041. Koh Kong Prov.: 1 wingless male, nr. sence of punctations on the dorsum of the head, and Thmar Bang, CL 6017. Pursat Prov.: 3 wingless males, 4 open female connexival structures which do not con- wingless females, nr. Vealveang, CL 6024. verge over abdominal tergites V–VII. In the key of Ecological notes. This very small species, conspicu- Torre-Bueno (1925) to Indian Microvelia, these new ously marked with black and white, is locally abun- species run to various taxa which, although exhibit- dant along the margins of quiet stream pools. It was ing certain similarities, also have obvious differences, originally described from Vietnam, and until now with these being discussed under each individual known only from that country. species treatment. The genus Microvelia as currently interpreted is undoubtedly para- or polyphyletic, but a reso- Subfamily Microveliinae China & Usinger lution of this problem is beyond the scope of the Genus Microvelia Westwood present paper. The widespread M. douglasi and re- cently described M. falcata are members of the sub- genus Picaultia (Andersen & Weir 2003), whereas Discussion. As noted by Andersen et al. (2002a), the all of the other Microvelia species so far taken in Microvelia fauna of Southeast Asia has not been re- Cambodia are assignable at present to the nominate vised since the work of Lundblad (1933), and many subgenus. undescribed species are known to occur in the re- gion. Three new species of Microvelia are described below, based on recent Cambodian collections. In Key to males of the species of addition, two other species are at hand, represented Microvelia by one or two females only, that also likely represent known from Cambodia new species, but their description is deferred pending 1. Grasping combs present on both fore and the collection of male specimens. The widespread M. middle tibiae; genitalia asymmetrical, with douglasi Scott was also encountered during the cur- right paramere much larger than left �������������� rent surveys, but by contrast the similarly widespread ...... 2 (subgenus Picaultia) M. leveillei (Letheirry), widely referenced in the pre- – Grasping comb present on fore tibia only; vious literature under the now-synonymized name male genitalia symmetrical, with both param- M. diluta Distant, was not. In addition, the very re- eres of the same size and shape ���������������������� cently described M. falcata, an apparent Cambodian ��������������������������������� 3 (subgenus Microvelia) endemic, was taken at a single Cardamom Mountain 2. Male right paramere slender and tapering, foothill locality. acuminate, with apex coming to a sharp, acute The three new species described here appear to angle; body length equal to or exceeding 1.80 belong to a closely related assemblage of species mm ��������� Microvelia (Picaultia) douglasi Scott with blackish to brown ground coloration, extensive – Male right paramere broader, gently curv- patches of silvery hairs on the abdominal dorsum, ing and of relatively even width throughout, and slender, elongate, sickle-shaped male parameres. with apex blunt; body length equal to or The male genitalic structures of all these new species less than 1.65 mm ������������������������� Microvelia are not congruent with any illustrated by Lundblad (Picaultia) falcata Zettel, Phauk, Kheam & Freitag (1933). 3. Body length less than 1.9 mm; fore tibia ex- Andersen et al. (2002a) provided a key to the panded and flattened on distal half (Fig. 38); Microvelia species occurring in Singapore and Pen- abdominal tergites III–V with extensive patch- insular Malaysia, and Torre-Bueno (1925) presented es of recumbent silvery setae (Fig. 37). . . . a key to the species found in India and Ceylon. Use ���������������� Microvelia (Microvelia) bokor n. sp. of these resources, in combination with Lundblad’s – Body length exceeding 2.2 mm; fore tibia (1933) work and examination of comparative mate- not expanded and flattened on distal half; rial at the Smithsonian Institution, has provided ad- abdominal tergites IV and V lacking patch- ditional confidence in the validity of the new species es of recumbent silvery setae (Figs 25, 26, described here. In the key of Andersen et al. (2002a), 32, 33)...... 4 all three of the new species described herein will run 4. Body set with numerous long, erect setae to the couplet containing M. petraeus Andersen, (Figs 32, 33); genital segment projecting Yang & Zettel and M. plumbea Lundblad, the lat- posteriorly from end of abdomen (Fig. 32); ter species now placed in the subgenus Pacificovelia abdominal ventrite VII (final segment before (Andersen & Weir 2003). The new Cambodian spe- genital capsule) not depressed or concave; cies are easily separated from these two taxa by their paramere with apex rounded (Figs 35, 36);

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tylus shining blackish, strongly contrast- Ecological notes. The specimens were taken from the ing with dull brown coloration of adjacent margins of a quiet, shaded stream pool. frons ����� Microvelia (Microvelia) setifera n. sp. – Body generally lacking long, erect setae Microvelia (Microvelia) penglyi n. sp. (Figs 25, 26); genital segment retracted into Figs 25–31 end of abdomen (Figs 25, 27); abdominal ven- trite VII (final segment before genital capsule) Type material. Holotype, micropterous male, Cam- broadly depressed and concave across its entire bodia, Pursat Prov., Cardamom Mountains, O Sarb width (Fig. 27); paramere with apex pointed Morth stream (= Sap Mat stream), N of Vealveang vil- (Figs 29, 30); tylus dark blackish brown, not lage on road to Pursat, 230 m [760 ft], 12°18'31''N, strongly contrasting with similar coloration on 103°06'36''E, water temp. 27°C, 2 September 2015, frons ������ Microvelia (Microvelia) penglyi n. sp. 08:00–09:30 hrs, CL 6024, D.A. Polhemus (USNM). Paratypes: Cambodia, Kampong Speu Prov.: 2 wing- Microvelia (Picaultia) douglasi Scott less males, Kirirom Plateau, Tasek Stream, cross- Microvelia douglasi Scott, 1874: 448. ing at second bridge on road up to summit, 640 m [2095 ft], 11°19'23''N, 104°04'59''E, water temp. Material examined. Cambodia, Kampong Speu Prov.: 25°C, 4 June 2016, 9:30–10:30 hrs, CL 6047, D.A. 2 winged males, 1 winged female, Sva Slab, CL 6034. Polhemus (BPBM). Koh Kong Prov.: 1 wingless fe- Sihanoukville Prov.: 2 winged males, Thmar Roung, CL male, Cardamom Mountains, O An Dart River, at 6038. highway bridge ~73 km SE of Koh Kong, 27 m [90 Discussion. The genus Picaultia was described by ft], 11°16'38''N, 103°19'47''E, water temp. 26°C, Distant (1913) based on the type species Microv­ 30 August 2015, 11:45–13:00 hrs, CL 6015, D.A. elia pronotalis from the Seychelles islands. Andersen Polhemus (BPBM); 1 wingless female, Cardamom & Weir (2003) reduced Picaultia to a subgenus of Mountains, Toeuk Noeng River, 9 km SSE of Thmar Microvelia, and placed M. douglasi within it, along Bang village crossroads, 165 m [550 ft], 11°37'33''N, with 18 other species of Microvelia occurring from 103°28'51''E, water temp. 26°C, 31 August 2015, Europe and Africa eastward through Asia to the 14:45–16:00 hrs, CL 6020, D.A. Polhemus (BPBM). Solomon ­Islands. All of these species possess grasp- Pursat Prov.: 1 wingless male, 12 wingless females, ing combs on both the fore and middle tibiae in the same data as holotype (BPBM, USNM). males, and have highly asymmetrical male genitalia, with the right paramere much larger in size than Description the left. Microvelia douglasi was originally described from Micropterous male (Fig. 25). Length 2.20–2.30 Japan, and as interpreted by Lundblad (1933), who mm (​ x ̅​ = 2.25, n = 3); width 0.75–0.80 mm undertook a detailed morphological analysis of the (​ x ̅​ = 0.78, n = 3). ­species, has a range extending from India eastward Color. Ground color dark blackish-brown, marked through Indochina to Indonesia, the Philippines, with orange–brown on anterior pronotum and outer New Guinea, Australia, Japan, the Mariana Islands portions of connexiva orange–brown; patches of and Samoa. As such, its presence in Cambodia is not short, shining, silvery pubescence present laterally on surprising. pronotum, metanotum, and abdominal tergites II, Ecological notes. Specimens were taken from the III, VI and VII, and connexival sutures. Head dark margins of quiet stream pools. blackish-brown; eyes dark red; antennae uniformly medium brown; rostrum dark yellow, dark brown along medial line, piceous distally. Pronotum dark Microvelia (Picaultia) falcata Zettel, Phauk, blackish-brown, bearing an elongate transverse or- Kheam & Freitag ange–brown patch behind anterior margin, width of Microvelia (Picaultia) falcata Zettel, Phauk, Kheam this patch subequal to width of vertex, patch faintly & Freitag, 2017: 27. divided medially by narrow, diffuse dark brown lon- gitudinal line. Metanotum and abdominal tergites Material examined. Cambodia, Kampong Speu Prov.: 2 dark blackish-brown, connexiva orange–brown on winged males, 1 winged female, nr. Rolak, CL 6041. outer halves and ventrally. Legs with femora yellow- Discussion. This species was recently described from ish brown with distal apices darker brown; tibiae specimens taken in Province. The record dark brown, each with yellowish brown annulation from Rolak village now extends the known range to centrally; tarsal segment I and base of tarsal segment the foothills of the Cardamom Mountains in Kam- II yellowish-brown, remainder of tarsal segment II pong Speu Province. This species appears to be en- dark brown. Ventral surface uniformly dull, dark demic to Cambodia. blackish-brown, except genital segments brown. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

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Figs 25–26. Microvelia penglyi n. sp., dorsal habitus; specimens from Cambodia, Pursat Prov., Vealveang, CL 6024. 25. Micropterous male. 26. Micropterous female.

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Fig. 27. Microvelia penglyi n. sp., male terminal abdominal ventrite VII, ventral view; specimen from Cambodia, Pursat Prov., Vealveang, CL 6024.

Structural characters. Head — Of moderate length, erect brown setae present along anterior margins of declivant anteriorly, with weak impressed me- all antennal segments, length of these setae on seg- dian line; length 0.35, width 0.55; width of eye/ ment I slightly exceeding width of segment, lengths interocular space, 0.10/0.35. Antennal formula I : of setae on segments II–IV at least 2× the widths of II : III : IV; 0.25 : 0.30 : 0.35 : 0.45. these segments. Pronotum — Long, covering mesonotum, poste- Legs — Fore femur with ventral margin straight, rior lobe coarsely punctate, length/width, 0.30/0.70. not modified, bearing numerous short, erect pale se- Metanotum coarsely punctate, length 0.25. Abdom- tae along entire length; fore tibiae with inner margin inal tergites coarsely punctate, dull, without shining straight, distal grasping comb very short, present as areas; lengths of tergites II–VII, respectively: 0.20: a small, dark, curving spur ventrally at apex, ante- 0.15 : 0.15 : 0.20 : 0.25 : 0.30. rior margin of fore tibia with scattered long, erect, Dorsal surface — Entire dorsum and lateroter- pale setae; middle femur unmodified, bearing a gites covered with fine appressed pale pubescence, fringe of short, erect pale setae along ventral margin intermixed with scattered, short, semi-erect dark intermixed with a few longer setae distally; middle setae; patches of moderately long, recumbent, pos- tibia with posterior margin bearing a row of evenly teriorly-directed silvery setae present along posterior spaced, long, pilose, pale setae of progressively de- margin of transverse yellowish-brown patch on an- creasing length, longest and most basal of these setae terior pronotum, along lateral margins of mesono- with length exceeding 2× width of tibia; hind femur tum, along posterior margins of abdominal tergites unmodified, with numerous short, erect pale setae II and III, sparingly as a narrow transverse band along ventral margin; claws long, slender, gently across central section of abdominal tergite III, as a curving. Proportions of legs as follows: Femur, tibia, large and prominent patch covering most of central tarsal 1, tarsal 2 of fore leg, 0.60 : 0.55 : 0.30; of mid- section of abdominal tergite VI, as small and diffuse dle leg, 0.70 : 0.70 : 0.20 : 0.25; of hind leg, 0.75 : patch centrally on abdominal tergite VII, and along 0.80 : 0.15 : 0.20. all connexival sutures; wing pads present as small, Ventral surface — Pro-, meso-, and metasterna subtriangular transverse flaps arising beneath pos- broadly sulcate along longitudinal midlines; ab- terolateral margins of pronotum; legs and antennae dominal ventrite I oriented vertically, with small thickly clothed with short pale setae, scattered long tumescence centrally. Abdominal venter set with

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D. A. Polhemus: Cambodian Aquatic Heteroptera 113

Figs 28–31. Microvelia penglyi n. sp., male genitalic structures; specimens from Cambodia, Kampong Speu Prov., Kirirom Plateau, CL 6047. 28. Proctiger. 29. Paramere, lateral view. 30. Paramere, alternate oblique view. 31. ­Posterior margin of pygophore, showing angulate lateral lobes. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

114 Tijdschrift voor Entomologie, volume 160, 2017 moderately long, recumbent, pale setae; abdominal are ­diagnostic and do not match any illustrated in ventrites I–VI unmodified; ventrite VII broadly de- ­Lundblad (1933). pressed centrally (Fig. 27). In the key of Andersen et al. (2002a) this species Male genitalia — Male genital segment retract- runs to the couplet containing M. plumbea Lund- ed into abdomen; proctiger elongate, with small, blad and M. petraeus Andersen, Yang & Zettel, but rounded lateral lobes basally, distal section roughly as noted in the generic discussion under Microvelia triangular with apex slightly produced (Fig. 28); as a whole it does not represent either of those spe- paramere slender, elongate, sharply bent at base, cies. Based on the original description and figures distal section tapering, apex slightly expanded and provided by Lundblad (1933), M. penglyi may be bulb-like (Figs 29, 30); pygophore with posterior separated from M. plumbea, which is now placed margin broadly excavate centrally, this central de- in the separate subgenus Pacificovelia (Andersen & pression flanked to either side by small, angular lobes Weir 2003), by its somewhat greater body length (Fig. 31). (2.20–2.75 mm, vs 2.00–2.20 mm for M. plumbea), Micropterous female (Fig. 26). Similar to micropter- absence of lateral processes on the male proctiger, ous male in general structure and color, with the fol- retracted male genital segment, differently shaped lowing exceptions: length 2.60–2.75 mm (​ x ̅​ = 2.63, male paramere, and open female connexiva, which n = 5); width 1.10–1.15 mm (​ x ̅​ = 1.01, n = 5); ab- are not tightly appressed over abdominal tergites dominal tergite I with silvery setae at posterolateral V–VIII. Based on the original description and fig- angles only, abdominal tergite II with a pair (1 + 1) ures presented in Andersen et al. (2002b), M. penglyi of large silvery hair patches on posterior half to either may also be separated from M. petraeus on the ba- side of longitudinal midline, abdominal tergites V sis of its much greater body length (2.20–2.75, vs and VI both with large patches of silvery setae cen- 1.19–1.40 in M. petraeus), differently shaped male trally; connexiva broadly and evenly bowed outward, paramere, and absence of dark punctures on the dor- convergent posteriorly but leaving abdominal tergite sal surface of the head. VII completely exposed, posterolateral apices of seg- In Torre-Bueno’s (1925) key to Indian Microvelia, ment VII not produced, lacking setal tufts; connex- this species provisionally runs to M. albomaculata, ival margins of even width throughout; abdominal described by Distant (1909) from East Bengal. Based venter unmodified, set with numerous very short on examination of 2 winged males and 1 winged pale setae; legs unmodified, fore tibia lacking grasp- female from Calcutta, India, held in the USNM, ing comb. M. penglyi clearly differs from that species in being Macropterous male. Unknown. much larger in size (with a body length 2.20–2.75 Macropterous female. Unknown. mm, vs less than 2.0 mm in M. albomaculata); in Etymology. The name “penglyi” honors Ly Peng La lacking the pale transverse yellowish marking be- of the Conservation International Greater Mekong hind the vertex present in M. albomaculata; and Program, who guided the author to the type locality. in possessing dark tibiae with broad yellowish an- Comparative notes. Microvelia penglyi can be rec- nulations centrally, with such annulations absent in ognized within the known Cambodian Microvelia M. albomaculata. assemblage by its relatively large size (body length Ecological notes. Microvelia penglyi occurs along the 2.20–2.75 mm); the small male fore tibial grasp- margins of moderate-sized streams at elevations from ing comb which is represented by a short, dark, 25 to 640 m, generally in areas of slower flow. ­curving spur near the apex (similar to M. bokor n. sp. described­ subsequently); the modification of male abdominal segment VII (the final segment Microvelia (Microvelia) setifera n. sp. ­before the genital capsule), which is broadly de- Figs 32–36 pressed and ­concave across its entire width (Fig. 27), the coloration of the tibiae, each of which is brown Type material. Holotype, micropterous male, Cam- with a broad yellowish-brown annulation centrally bodia, Koh Kong Prov., Cardamom Mountains, (Figs 25, 26); and the details of the male genitalia O An Dart River, at highway bridge ~73 km SE of (Figs 28–31). This species is superficially similar in Koh Kong, 27 m [90 ft], 11°16'38''N, 103°19'47''E, size and appearance to M. setifera n. sp., described water temp. 26°C, 30 August 2015, 11:45–13:00 subsequently, with which it is occasionally syn- hrs, CL 6015, D.A. Polhemus (USNM). Paratypes: topic, but can be separated from that species by the Cambodia, Kampong Chhnang Prov.: 3 wingless absence of long, erect setae dorsally and laterally females, 20 m [70 ft], 12°23'04''N, 104°29'11''E, ­(compare Figs 25, 26 to Figs 32, 33), the retracted water temp. 29°C, 2 September 2015, 15:00–15:45 male genital capsule (compare Figs 25 and 32), and hrs, CL 6025, D.A. Polhemus (BPBM). Koh Kong the structures of the male genitalia (compare Figs Prov.: 2 wingless males, 6 wingless females, same 28–31 to Figs 34–36). The male genitalic structures data as holotype (BPBM, USNM). Pursat Prov.: Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 115

Figs 32–33. Microvelia setifera n. sp., dorsal habitus; specimens from Cambodia, O An Dart River, CL 6015. 32. Micropterous male. 33. Micropterous female. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

116 Tijdschrift voor Entomologie, volume 160, 2017

Figs 34–36. Microvelia setifera n. sp., male genitalic structures; specimen from Cambodia, Koh Kong Prov., O An Dart River, CL 6015. 34. Proctiger. 35. Paramere, oblique view. 36. Paramere, alternate lateral view.

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D. A. Polhemus: Cambodian Aquatic Heteroptera 117

2 wingless males, 1 wingless female, Cardamom along inner margins of connexiva adjoining lateral Mountains, O Sarb Morth stream (= Sap Mat margins of abdominal tergites II and III, and also stream), N of Vealveang village on road to Pursat, tergites VI and VII; wing pads present as small, sub- 230 m [760 ft], 12°18'31''N, 103°06'36''E, water quadrate transverse flaps arising beneath posterolat- temp. 27°C, 2 September 2015, 08:00–09:30 hrs, eral margins of pronotum; legs and antennae thickly CL 6024, D.A. Polhemus (BPBM). clothed with short pale setae, scattered long erect brown setae present along anterior margins of anten- nal segments I–III, lengths of these setae exceeding Description 2× the width of the segments on which they occur. Micropterous male (Fig. 32). Length 2.50–2.60 mm Legs — Fore femur with ventral margin straight, (​ x ̅​ = 2.53, n =3); width 0.80–0.90 mm (​ x ̅​ = 8.33, not modified, bearing a row of ~10 very long, pale, n = 3). erect, evenly spaced setae; fore tibiae with inner mar- Color. Ground color dark blackish-brown, marked gin straight, anterior and posterior margins bearing with orange–brown on anterior pronotum and scattered long, erect dark setae, distal grasping comb outer portions of connexiva; patches of short, shin- very short, length about one-fourth that of tibia; ing, silvery pubescence present laterally on prono- middle femur unmodified, anterior margin bear- tum, metanotum, and abdominal tergites II and III ing scattered long, erect dark setae, posterior mar- and anterior and posterior portions of connexiva. gin bearing an evenly spaced row of ~12 very long, Head dull medium brown; tylus shining dark black- pale, erect setae; middle tibia with anterior margin ish brown; eyes dark red; antennae medium brown, bearing scattered long, erect dark setae, posterior with distal half of segment I and basal half of seg- margin bearing a row of evenly spaced, long pilose ment II lighter brown; rostrum dark yellow, dark dark setae of progressively decreasing length, longest brown along medial line, piceous distally. Pronotum and most basal of these setae with length exceeding dark blackish-brown, bearing an elongate trans- 2× width of tibia; hind femur and tibia unmodified, verse orange–brown patch behind anterior margin, both bearing numerous long, erect dark setae along width of this patch subequal to width of vertex. both anterior and posterior margins; claws very long, Metanotum and abdominal tergites dark blackish- slender, gently curving. Connexiva evenly converg- brown, connexiva orange–brown on outer halves ing posteriorly, bowed gently outward. Proportions and ventrally. Legs with femora pale yellowish on of legs as follows: femur, tibia, tarsal 1, tarsal 2 of fore basal halves, dark brown on distal halves; tibiae dark leg, 0.70 : 0.60 : 0.30; of middle leg, 0.85 : 0.75 : brown, each with broad dark yellowish annulation 0.15 : 0.25; of hind leg, 0.90 : 1.10 : 0.20 : 0.25. centrally; tarsal segment I and base of tarsal segment Ventral surface — Ventral thorax and abdomen II yellowish-brown, remainder of tarsal segment II with numerous coarse punctations; prosternum dark brown. Ventral surface uniformly dull, dark deeply sulcate along longitudinal midline between blackish-brown, longitudinal midline of abdomen acetabulae, mesosternum weakly sulcate along lon- narrowly shining; genital segments brown, shining gitudinal midline, metasternum broadly domed, and darker basally. lacking longitudinal sulcus; abdominal ventrite I Structural characters. Head — Of moderate length, oriented vertically, with small, posteriorly projecting declivant anteriorly, with weak impressed median tumescence centrally. Abdominal venter set with nu- line, row of 4 coarse punctations present along each merous long, erect, pale setae; abdominal ventrites lateral margin of vertex adjacent to inner margins of I–VII unmodified, lacking carinae, tumescences or eyes; length 0.45, width 0.60; width of eye/interocu- depressions. lar space, 0.20/0.30. Antennal formula I : II : III : Male genitalia — Male genital segment protuding IV; 0.40 : 0.25 : 0.40 : 0.60. (Fig. 32); proctiger elongate, parallel sided, lacking Pronotum — Long, covering mesonotum, coarse- lateral lobes, apex rounded (Fig. 34). Paramere slen- ly punctate, length/width, 0.45/0.75. Metanotum der, gently curving, apex rounded, slightly bulbous coarsely punctate, length 0.18. Abdominal ter- and hooked (Figs 35, 36). gites II–V dull, coarsely punctate, tergites VI–VIII Micropterous female (Fig. 33). Similar to micropter- smooth, shining; lengths of tergites II–VIII, respec- ous male in general structure and color, with fol- tively: 0.18: 0.18 : 0.15 : 0.15 : 0.15 : 0.25 : 0.20. lowing exceptions: length 2.80–2.95 mm (​ x ​ = 2.88, Dorsal surface — Entire dorsum and lateroter- ̅ n = 5); width 0.90–1.10 mm (​ x ̅​ = 1.00, n = 5); mesono- gites covered with fine appressed pale pubescence, tum and abdominal tergites II and III bowed broadly intermixed with numerous, long, erect dark setae; and gently upward, abdominal tergite IV angled patches of moderately long, recumbent, silvery setae downward, abdominal tergites V–VIII horizontal, present laterally within transverse yellowish-brown deeply recessed below connexiva; coarse punctations patch on anterior pronotum, along lateral margins present on abdominal tergites II and III only; con- of mesonotum and abdominal tergites II and III, and nexiva weakly posteriorly convergent adjacent to Downloaded from Brill.com10/07/2021 06:11:13PM via free access

118 Tijdschrift voor Entomologie, volume 160, 2017 meosnotum and abdominal tergite II, more strongly much greater body length (2.50–2.95, vs 1.19–1.40 convergent adjacent to tergites IV–VII, parallel ad- in M. petraeus), differently shaped male paramere, jacent to tergite VIII; mesonotum and abdominal and absence of dark punctures on the dorsal surface tergites II and III with broad patches of silvery se- of the head. tae laterally, tergite II also with a small silvery patch This species runs to M. longicornis Torre-Bueno, centrally along posterior margin, other small patches endemic to Ceylon, in the key to Indian Microvelia of silvery setae present along inner margins of con- species provided by Torre-Bueno (1925). It is similar nexiva adjacent to abdominal tergites V and VI, and to that species in general size and body form, shar- along posterior margin of abdominal tergite VII; ing the elongate antennae and legs in relation to the connexival margins of even width throughout, pos- length of the body, with antennal segment IV being terolateral angles of connexiva not produced, lacking 1.5× the length of segment I, the prominent patches setal tufts; abdominal venter unmodified, set with of silvery setae laterally on the metanotum, and a numerous very short pale setae, lacking long erect fuzzy overall appearance created by numerous erect, setae; legs unmodified, fore tibia lacking grasping dark setae on the dorsum and laterally. The author comb. has been able to examine 15 male and female speci- Macropterous male. Unknown. mens of M. longicornis collected 4 miles west of Padi- Macropterous female. Unknown. yatalawa, Ceylon by P. and P. Spangler on 6 April Etymology. The name “setifera” is derived from the 1971, determined by P. B. Karunaratne, and held in Latin setifer, meaning bearing bristles, and refers to the USNM. Based on this comparison, M. setifera the numerous erect hairs on the body of this species. can be separated from M. longicornis by its brown- Comparative notes. Microvelia setifera can be sepa- ish coloration (vs black in M. longicornis), prominent rated from other Cambodian Microvelia species by patches of silvery setae laterally on the basal abdomi- the numerous erect hairs dorsally and laterally, which nal tergites and at certain points on the inner con- give the species a fuzzy appearance (Figs 32, 33), the nexiva (such silvery setae being present only as very short grasping comb on the male fore tibia, which narrow bands along the dorsal abdominal sutures in extends approximately one-fourth the length of the M. longicornis), in having only the distal half of the tibia, the very long claws, the presence of evenly middle femora dark in both sexes (vs the distal two- spaced rows of long erect setae posteriorly on the thirds dark in M. longicornis), and by the structure of fore and middle femora, the presence of numer- the male genitalia (Figs 34–36). ous coarse punctations on the ventral surface of the Two other continental Asian Microvelia species thorax and abdomen, and the structure of the male also possess long setae on the body and legs, M. genitalia (Figs 34–36). A very useful spot character annandalei Distant (1909) and M. burmanica Paiva which aids in recognition of this species is the shin- (1918), but according to their original descriptions ing, dark brown tylus, which contrasts strongly with both of these species are smaller, with body lengths the dull, medium brown coloration of the frons. For of 2.0 mm or less. The paramere of M. annandalei as additional discussion of characters separating this illustrated by Lundblad (1933) is of a different shape species from M. penglyi see the remarks under that than that of M. setifera, with a notched apex which is species. The male genitalic structures of M. setifera not present in the Cambodian species. The paramere do not match any illustrated in Lundblad (1933). of M. burmanica has never been illustrated and thus In the key of Andersen et al. (2002a) this species cannot be compared. runs to the couplet containing M. plumbea Lund- In addition, several Microvelia species similar to blad and M. petraeus Andersen, Yang & Zettel, but as M. setifera are present in the author’s collections noted in the generic discussion under Microvelia as from central and northern Vietnam. All are dorsally a whole it does not represent either of those species. setiferous, have a long and projecting genital capsule, Based on the original description and figures provid- and possess a long basal process on the male param- ed by Lundblad (1933), M. setifera may be separated ere. In material from Nghe An Prov., Vietnam (CL from M. plumbea, which is now placed in the sepa- 4387), the apex of the male paramere is notched, just rate subgenus Pacificovelia (Andersen & Weir 2003), as shown by Lundblad (1934) for M. annandalei, but by its somewhat greater body length (2.50–2.95 it is not clear if this sample truly represents that spe- mm, vs 2.00–2.20 mm for M. plumbea), absence cies, because the author has not had the opportunity of lateral processes on the male proctiger, retracted to examine specimens from India. Other samples male genital segment, differently shaped male para- from the Vietnamese Central Highlands (CL 4384) mere, and open female connexiva, which are not and the northern Bac Can Province (CL 4374) have tightly appressed over abdominal tergites V–VIII. the apex of the paramere rounded as in M. setifera, Based on the original description and figures pre- but are larger in size, differ in the configuration of sented in Andersen et al. (2002b), M. penglyi may the female connexiva, and have different patterns also be separated from M. petraeus on the basis of its of dorsal coloration and setiferation, particularly in Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 119 regard to the distribution of silvery hair patches on Description the abdominal tergites. It therefore appears that Micropterous male (Fig. 37). Length 1.70–1.85 mm M. setifera is just one member in an assemblage of (​ x ̅​ = 1.76, n =3); width 0.70–0.75 mm (​ x ̅​ = 0.72, related species that occur from Ceylon through India n = 2). Wingless female, length 1.80–1.85 mm (​ x ̅​ into Indochina, the full documentation of which is = 1.83, n = 2); width 0.85–0.90 mm, (​ x ̅​ = 0.87, beyond the scope of the current paper. n = 2). Ecological notes. Microvelia setifera occurs along the Color. Ground color dark blackish-brown, with margins of moderate to large sized streams at eleva- head, pronotum, and outer portions of connexiva tions from 20–230 m, generally in areas of slower medium brown; patches of short, shining, silvery flow. Its habitat preferences are similar to those of pubescence present on pronotum, metanotum, ab- M. penglyi, and the two species are sometimes taken dominal tergites III–VI and connexival sutures. together, as seen at the O An Dart stream in Koh Head medium brown; eyes dark red; antennae uni- Kong Province, and the O Sarb Morth stream near formly medium brown; rostrum dark yellow, dark Vealveang in Pursat Province. brown along medial line, piceous distally. Pronotum medium brown. Metanotum and abdominal tergites dark blackish-brown, connexiva medium brown on Microvelia (Microvelia) bokor n. sp. outer halves and ventrally. Legs with femora pale yel- Figs 37–41 lowish, distal apices darker brown; tibiae and tarsi medium brown, lacking annulations. Ventral surface Type material. Holotype, micropterous male, Cam- uniformly dull, dark blackish-brown, except genital bodia, Kampot Prov., Elephant Mountains, Bokor segments brown, longitudinal midline of abdomen Plateau, rocky stream in wet upland forest, ~20 km narrowly shining. from Hwy 3 on road to Bokor resort, 965 m [3165 ft], Structural characters. Head — Of moderate length, 10°37'33''N, 104°04'10''E, water temp. 22°C, 22 May declivant anteriorly, with weak impressed median 2016, 08:00–09:00 hrs, CL 6035, D.A. Polhemus line, a longitudinal row of 5 glabous foveae present (USNM). Paratypes: 2 wingless males, 2 wingless laterally along either side of vertex adjacent to inner females, same data as holotype (BPBM, USNM). margins of eyes; length 0.35, width 0.45; width of

Fig. 37. Microvelia bokor n. sp., micropterous male, dorsal habitus; specimen from Cambodia, Kampot Prov., stream on Bokor Plateau, CL 6035. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

120 Tijdschrift voor Entomologie, volume 160, 2017

Fig. 38. Microvelia bokor n. sp., male foreleg showing distal expansion of fore tibia; specimen from Cambodia, Kampot Prov., stream on Bokor Plateau, CL 6035. eye/interocular space, 0.10/0.25. Antennal formula acetabulae, mesosternum weakly sulcate along lon- I : II : III : IV; 0.20 : 0.20 : 0.30 : 0.40. gitudinal midline, metasternum broadly domed, Pronotum — Long, covering mesonotum, lacking longitudinal sulcus; abdominal ventrite I posterior lobe coarsely punctate, length/width, oriented vertically. Abdominal venter set with nu- 0.25/0.65. Metanotum length 0.15. Abdominal merous very short, pale, recumbent setae; abdominal tergites dull, without shining areas; lengths of ter- ventrites I–VII unmodified, lacking carinae, tumes- gites II–VII, respectively: 0.15: 0.10 : 0.10 : 0.12: cences or depressions. 0.15 : 0.25. Male genitalia — Male genital segment retracted Dorsal surface — Entire dorsum and laterotergites into abdomen; proctiger slightly expanded later- covered with short, appressed golden pubescence, ally, lacking basal lobes, distal section evenly taper- mostly lacking erect setae; patches of moderately ing with apex slightly produced (Fig. 39); paramere long, recumbent, silvery setae present along laterally slender, elongate, gently curving, apex acute, weakly on pronotum behind each eye, along lateral margins multidentate in certain views (Figs 40, 41); pygo- of mesonotum, narrowly along posterior margin of phore unmodified. abdominal tergite III, as prominent paired (1 + 1) Micropterous female. Similar to micropterous male in patches laterally on tergites IV and V, as small paired general structure and color, including distribution of (1 + 1) patches posterolaterally on tergite VI, and silvery hair patches dorsally, with following excep- along all connexival sutures; wing pads present as tions: connexiva more broadly and evenly bowed small, subtriangular transverse flaps arising beneath outward, convergent posteriorly but leaving abdom- posterolateral margins of pronotum; legs and anten- inal tergite VII completely exposed, posterolateral nae thickly clothed with short pale setae, scattered apices of segment VII not produced, lacking setal long erect brown setae present along anterior mar- tufts, connexival margins of even width throughout. gins of all antennal segments, lengths of these setae Abdominal venter unmodified, set with numerous at least 2× the widths of the segments on which they very short pale setae; gonocoxae tightly appressed arise. along posterior margins, lying at 45° angle. Legs un- Legs — Posterior margins for fore femur, middle modified, fore tibia lacking grasping comb. femur and middle tibia bearing a few longer, erect Macropterous male. Unknown. pale setae; fore femur slightly bowed, expanded and Macropterous female. Unknown. ventrally flattened on distal one-half to accomodate Etymology. The name “bokor” is a noun in apposi- grasping comb (Fig. 38); middle and hind femora, tion and refers to the Bokor Plateau of southwestern tibiae and tarsi unmodified; claws long, slender, gen- Cambodia, the type locality for this new species. tly curving. Proportions of legs as follows: Femur, Discussion. Microvelia bokor is similar to M. peng­ tibia, tarsal 1, tarsal 2 of fore leg, 050 : 0.45 : 0.22; lyi in many respects, but much smaller in size (body of middle leg, 0.55 : 0.50 : 0.10 : 0.15; of hind leg, length 1.70–1.85 mm, vs 2.20–2.75 mm in M. peng­ 0.55 : 0.70 : 0.10 : 0.15. lyi), and with a different pattern of silvery setifera- Ventral surface — Venter of thorax and abdo- tion on the dorsal abdomen (compare Figs 25, 26 to men with numerous coarse punctations; prosternum Fig. 37). In addition, the male fore tibia is distinctly deeply sulcate along longitudinal midline between expanded on its distal half, with the grasping comb Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 121

Figs 39–41. Microvelia bokor n. sp., male genitalic structures; specimen from Cambodia, Kampot Prov., stream on Bokor Plateau, CL 6035. 39. Proctiger. 40. Paramere, lateral view. 41. Paramere, alternate oblique view.

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122 Tijdschrift voor Entomologie, volume 160, 2017 represented by a short spur near the apex (Fig. 38). Material examined. Cambodia, Koh Kong Prov.: 1 As in M. penglyi the male genital capsule is retracted ­macropterous male, 1 micropterous female, O An Dart, (Fig. 37), the posterior margins of the femora and CL 6015, D.A. Polhemus (USNM). tibiae lack combs of long, erect setae, and the dor- Discussion. Pseudovelia pusilla stands apart from oth- sum and pleurae also lack long, erect setae, bearing er species of Microveliinae collected in Cambodia on only short, golden setae. The male genitalic struc- the basis of its orange–brown coloration; the pres- tures are diagnostic, particularly the shape of the ence of two ocular setae near the posterior margin paramere (Figs 40, 41), which does not match any of the eye; the very long grasping comb on the male illustrated in Lundblad (1933). fore tibia, which extends for over half the length of In Torre-Bueno’s (1925) key to Indian Micro­ the segment; and the structure of the male genita- velia, this species runs to M. singalensis, described by lia including the stout, roughly quadrate proctiger Kirkaldy from Pundaluoya, Ceylon. The holotype of and highly reduced, paddle-shaped parameres. The M. singalensis, a winged female held in the Smith- forewings of the macropterous male are uniformly sonian Institution, was examined for comparison, fuscous, lacking any pale markings. and although similar in general size, the two species This species was originally described from the are clearly different. In particular, M. bokor lacks the Dalat Plateau of southern Vietnam (Hecher 1997), broad, pale transverse yellowish marking behind the and subsequently recorded from Yunnan, China (Ye et vertex that spans the entire anterior width of the al. 2013). The current Cambodian collections extend pronotum in M. singalensis; has the distal halves of the geographic range further to the south and west. the femora marked with brown, whereas in M. sin­ Ecological notes. A pair of specimens was taken from galensis they are uniformly straw yellow, without any the vegetated margins of stream pools at the O An dark distal marks; and possesses 5 large, dark foveae Dart, an amber water stream in a sand and cobble bed. on either side of the vertex along the inner margins of the eyes, which are lacking in M. singalensis. A Subfamily Perittopinae China & Usinger comparison on the basis of male genital structures is not currently possible, because the holotype of M. singalensis is a female. Perittopus asiaticus Zettel In the key of Andersen et al. (2002a) this species Perittopus asiaticus Zettel, 2001: 110. runs to the couplet containing M. plumbea Lundblad and M. petraeus Andersen, Yang & Zettel, but fails at Material examined. Cambodia, Kampot Prov.: 6 winged this point due to incongruent character states. Based males, 8 winged females, Bokor Plateau, CL 6035; 10 on the original description and figures provided by winged males, 3 winged females, Bokor Plateau, CL 6037. Lundblad (1933), M. penglyi may be separated from Discussion. The specimens of P. asiaticus from Cam- M. plumbea, which is now placed in the separate bodia conform to the concept for this widespread subgenus Pacificovelia (Andersen & Weir 2003), Southeast Asian species adopted by Ye et al. 2013, by its slightly shorter body length (1.70–1.85 mm, particularly in regard to the shape of the male para- vs 2.00–2.20 mm for M. plumbea), absence of lat- mere and proctiger presented in that work. The eral processes on the male proctiger, retracted male paramere shape depicted by the above authors is genital segment, differently shaped male paramere, somewhat different than that presented in the origi- and open female connexiva, which are not tightly nal description by Zettel (2001), with the distal lobe appressed over abdominal tergites V–VIII. Based somewhat fuller and more rounded, but this may be on the original description and figures presented accounted for by the fact that these two works ap- in Andersen et al. (2002b), M. penglyi may also be pear to have illustrated the structure in slightly dif- separated from M. petraeus on the basis of its much ferent orientations. greater body length (1.70–1.85, vs 1.19–1.40 in M. Ecological notes. Individuals were found on shaded petraeus), differently shaped male paramere, and pools along high, cool streams on the crest and flanks absence of dark punctures on the dorsal surface of of the Bokor Plateau, at elevations between 815 and the head. 965 m. Ecological notes. The type series of Microvelia bokor was taken from the margins of pools formed along a small upland streamlet on the top of the Bokor Pla- Subfamily Rhagoveliinae China & Usinger teau, heavily shaded by evergreen montane rainforest. Rhagovelia inexpectata Zettel Figs 42, 44, 45, 48–50 Pseudovelia pusilla Hecher Pseudovelia pusilla Hecher, 1997: 47. Rhagovelia inexpectata Zettel, 2000: 176.

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Material examined. Cambodia, Koh Kong Prov.: 1 1 wingless male, nr. Rolak, CL 6041; 13 wingless males, 13 winged female, nr. Thmar Bang, CL 6017; 1 winged wingless females, nr. Krong Chbar Mon, CL 6045. female, 1 wingless male, 2 wingless females, Toeuk Noeng, Discussion. This species may be easily recognized CL 6020. Pursat Prov.: 1 winged male, 3 wingless females, among the Veliidae of Cambodia by the presence nr. Vealveang, CL 6024. Sihanoukville Prov.: 6 wingless of finely bifurcating swimming plumes on both the males, 8 wingless females, nr. Pich Nil, CL 6039. middle and hind tarsi, and by the strongly alternat- Discussion. This species superficially resemblesR. ing pale and dark annulations on the legs (Fig. 51). sumatrensis, bearing stout spines basoventrally on Ecological notes. Originally described from Thailand the male middle femur (Fig. 44), but the paramere (Andersen 2000), and until now known only from is shorter, more robust, and not hooked at apex as that country, Tetraripis zetteli was found as scat- in R. sumatrensis. The Cambodian specimens have tered colonies on various streams in the Cardamom been compared to material from the Central High- Mountain premontane foreland in Kampong Speu lands of Vietnam (CL 4297), and match in all par- Province. In all cases the insects were quite localized ticulars, including the spination of the male hind leg along any given stream, aggregating in dark pock- (Fig. 45) and the stout form of the male paramere ets beneath undercut banks. Repeated splashing and when viewed laterally (Figs 48, 49). scooping of such pockets could sometimes result in Although Figs 7 and 8 in Zettel (2000) are suf- capture of a large number of specimens, indicating ficient to illustrate the difference between the stout that adults may be sheltering above the water line. male paramere in R. inexpectata and the more slen- Tetraripis zetteli is almost undoubtedly nocturnal der, hooked paramere in R. sumatrensis when viewed in the adult stage, although immatures were found laterally, they do not convey the true degree of con- skating during daylight hours amid low emergent cavity at the truncate apex of the paramere in R. vegetation swept by the current along the margins of inexpectata, which is evident in specimens from both a channelized lowland stream near Kampong Speu, Vietnam and Cambodia (Figs 48–50). In addition, in a manner reminiscent of Rhagovelia. there is a certain degree of intraspecific variation in the shape of the paramere among local populations in the Cardamom Mountains (Figs 48, 49). Subfamily Veliinae Brullé

Rhagovelia tebakang J. Polhemus & D. Polhemus Angilia (Adriennella) bispinosa Andersen Figs 43, 46, 47 Angilia (Adriennella) bispinosa Andersen, 1982: 345. Rhagovelia tebakang J. Polhemus & D. Polhemus, 1988: 186. Material examined. Cambodia, Kampong Speu Prov.: 1 male, 2 immatures, Kirirom, CL 6047. Material examined. Cambodia, Koh Kong Prov.: 4 Ecological notes. This species was originally described winged males, 3 wingless males, 3 wingless females, Koh from Thailand, and subsequently recorded from Kong–Pursat, CL 6023. Vietnam and Burma (Polhemus & Polhemus 2003), Discussion. This species was previously known only therefore its presence in Cambodia is not surprising. from Borneo. The Cambodian specimens, however, A single male specimen was taken from a stream on possess all the key characters of this species, includ- the flanks of the Kirirom Plateau, flowing through ing the expanded juga, presence of spinules on the native pine forest but shaded by a narrow band of male hind trochanter (Fig. 46), and an elongate, broadleaf riparian gallery forest. The single adult distally hooked male paramere (Fig. 47). They taken was found in a dark recess beneath a projecting therefore appear to represent the first record of this sandstone boulder along the stream margin. Several species from the Southeast Asian mainland. As with immatures were also taken from dark pockets along Rhagadotarsus borneensis and Hydrometra longicapitus vertical banks of red lateritic alluvium. The imma- discussed previously, this seems to represent another tures of this species have black bodies with strongly instance of a disjunct Sundaland distribution within contrasting white spots. the aquatic Heteroptera fauna of Cambodia.

Tetraripis zetteli Andersen Infraorder Fig. 51 Family Leach Tetraripis zetteli Andersen, 2000: 187. Diplonychus rusticus (Fabricius) Material examined. Cambodia, Kampong Speu Prov.: 7 Nepa rustica Fabricius, 1781: 333. wingless males, 3 wingless females, nr. Chambok, CL 6033; Diplonychus rusticus: Laporte, 1833: 18.

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Figs 42–43. Rhagovelia species, dorsal habitus. 42. R. inexpectata, apterous female, specimen from Cambodia, ­Sihanoukville Prov., stream below Kirirom hydroelectric plant, CL 6039. 43. R. tebakang, apterous female, speci- men from Cambodia, Koh Kong Prov., stream on Koh Kong to Pursat road, CL 6023.

Appasus marginicollis Dufour, 1863: 393; syn. by Family Helotrephidae Esaki & China Distant, 1906: 36. Diplonychus indicus Ventaktesan & Rao, 1980: 299; syn. by J. Polhemus, 1995: 651. Idiotrephes cf. shepardi Papácek & Zettel Idiotrephes shepardi Papacek & Zettel, 2000: Material examined. Cambodia, Kampong Speu Prov.: 208. 1 immature, nr. Krong Chbar Mon, CL 6045. Ecological notes. A single immature of this species was Material examined. Cambodia, Koh Kong Prov.: taken in a wetland along Hwy 4 near Kampong Speu. 1 brachypterous female, Toeuk Noeng, CL 6020. This is the only member of the genus present in Indo- Discussion. Only a single female of this species is china, and the species identification is not in doubt. at hand, rendering its determination as I. shepardi Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 125

Figs 44–46. Rhagovelia species, legs. 44. R. inexpectata, male left middle femur, dorsal view, showing stout spines ventrally near base; specimen from Cambodia, Sihanoukville Prov., stream below Kirirom hydroelectric plant, CL 6039. 45. R. inexpectata, male left hind leg, dorsal view; specimen from Cambodia, Sihanoukville Prov., stream below Kirirom hydroelectric plant, CL 6039. 46. R. tebakang, male left hind leg, dorsal view, note spinules on hind trochanter; specimen from Cambodia, Koh Kong Prov., stream on Koh Kong toDownloaded Pursat road, from Brill.com10/07/2021CL 6023. 06:11:13PM via free access

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Figs 47–50. Rhagovelia species, male right paramere, lateral view. 47. R. tebakang, specimen from Cambodia, Koh Kong Prov., stream on Koh Kong to Pursat road, CL 6023. 48–50. R. inexpectata, showing geographic variation in shape of paramere apex. 48. Specimen from Cambodia, O Sarb Morth stream near Vealveang, CL 6024. 49. Specimen from Cambodia, Touk Neong River, CL 6020. 50. Specimen from Vietnam, Quang Ngai Prov., NE of Kontum, CL 4297.

­provisional. The shape of the subgenital plate con- Family Micronectidae Jackzewski forms to the illustration for I. shepardi given in ­Papacek & Zettel 2000, but definitive confirmation Genus Micronecta Kirkaldy will require collection of male specimens. Discussion. The three species listed below can be de- finitively identified from the CambodianMicronecta Hydrotrephes maculatus Papácek & Kovac material at hand. In addition, one further series con- Hydrotrephes maculatus Papacek & Kovac, 2001: sisting of one male and two females from the Sva Slab 317. River (CL 6034), in Kampong Speu Province, pos- sesses male genitalic structures that do not match any Material examined. Cambodia, Kampong Speu Prov.: 1 figure in Lundblad (1933), Nieser & Chen (1999), male, 1 female, Sva Slab, CL 6034. or Nieser (1999, 2002). This taxon has a tan ground Discussion. The male genitalia of the Cambodian color with dark lateral patches along costa, but lacks male specimen at hand agree in all respects with the other significant markings. The right paramere is illustrations provided for this species by Papacek & very long and slender, similar to M. dentifera Nie- Kovac (2001). ser, while the left paramere is distinctively shaped. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

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Fig. 51. Tetraripis zetteli, apterous male, dorsal habitus; specimen from Cambodia, Kampong Speu Prov., stream near Krong Chbar Mon, CL 6045.

Because the author is not comprehensively familiar Material examined. Cambodia, Kampong Speu Prov.: with all Micronecta species occurring in Southeast 1 macropterous female, Sva Slab, CL 6034. Asia, description of this potential new species is de- Ecological notes. This species was taken from water- ferred pending further analysis. filled potholes in diabase bedrock along the Sva Slab River near Chambok. At this locality it co-occurred Micronecta guttatostriata Lundblad in the same pools along with Micronecta guttatostri­ Micronecta guttatostriata Lundblad, 1933: 101. ata Lundblad.

Material examined. Cambodia, Kampong Speu Prov.: Synaptonecta issa (Distant) 1 macropterous female, Sva Slab, CL 6034. Synaptonecta issa (Distant, 1910): 350. Ecological notes. This species was taken from water- filled potholes in diabase bedrock along the Sva Slab River near Chambok. At this locality it co-occurred Material examined. Cambodia, Kampong Speu Prov.: in the same pools along with Micronecta quadris­ 1 macropterous male, Sva Slab, CL 6034. Kampot­ trigata Breddin. Prov.: 1 brachypterous male, Bokor Plateau, CL 6036. Discussion. The macropterous male specimen from Micronecta polhemusi Nieser the Sva Slab River has fully developed hind wings, Micronecta polhemusi Nieser, 2000: 283. and a dark color pattern consisting of heavy brown mottling and small punctate dark brown dots. Material examined. Cambodia, Koh Kong Prov.: 4 mac- By contrast, the hemelytra of the brachypterous ropterous females, Toeuk Noeng, CL 6020. specimen from the Bokor Plateau has a much paler Ecological notes. This species was taken from water- color pattern, similar to that shown in Fig. 18.2 of filled potholes in sandstone bedrock along the Touek Tran et al. (2015). The differences in coloration were Noeng River in the central Cardamom Mountains. pronounced enough that at first it appeared two sepa- rate species might be at hand, but the male genitalic Micronecta quadristrigata Breddin structures in both specimens conform to those of Micronecta quadristrigata Breddin, 1905: 57. S. issa. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

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Ecological notes. The Bokor Plateau specimen was Family Nepidae Latreille taken from a deep, cold pond surrounded by upland rain forest on the nearly level summit of the moun- Subfamily Ranatrinae Douglas & Scott tain (Fig. 10). Cercotmetus asiaticus Amyot & Serville Cercotmetus asiaticus Amyot et Serville, 1843: 441. Family Naucoridae Leach Discussion. A previous record of this species from Heleocoris malayensis D. Polhemus & J. Polhemus southwestern Cambodia was provided by Polhemus Heleocoris malayensis D. Polhemus & J. Polhemus, & Polhemus (2013). It was not recollected during 2013: 676. the present surveys.

Material examined. Cambodia, Kampong Speu Prov.: 1 Cercotmetus brevipes brevipes Montandon female, Sva Slab, CL 6034. Cercotmetus brevipes brevipes Montandon, 1909: 65. Discussion. A single female that has been assigned to this species was taken along the margins of Material examined. Cambodia, Koh Kong Prov.: 1 male, Sva Slab River where it flowed across exposures Koh Kong–Pursat, CL 6023. of diabase bedrock northeast of Chambok village. Ecological notes. A single specimen was taken from This specimen has been identified asH. malayensis the shaded margins of a still pond formed upstream based on the shape of the subgenital plate, the of a road crossing, amid submerged grasses and twigs. apex of which is shallowly concave rather than possessing a V-shaped incision (see discussion in Ranatra thai Lansbury Polhemus & Polhemus 2013). Because the range of Ranatra thai Lansbury, 1972: 334. this species and that of H. ovatus Montandon over- lap in southern Indochina, definitive confirmation of this species in Cambodia must await collection Material examined. Cambodia, Kampong Speu Prov.: of male specimens. 2 males, 2 females, Sva Slab, CL 6034; 1 male, Kirirom, CL 6048. Kampot Prov.: 7 males, 8 females, Bokor Pla- teau, CL 6036. Sihanoukville Prov.: 1 male, Thmar Roung, Naucoris scutellaris Stål CL 6038. Naucoris scutellaris Stål, 1860: 266. Ecological notes. This species has been recorded Thurselinus greeni Distant, 1904: 33; syn. by from the Malay Peninsula northward into Vietnam, ­Lundblad, 1933: 65. Thailand, and now Cambodia (Tran & Polhemus Naucoris rhizomatus J. Polhemus, 1984: 157; syn. by 2012). Several good series were taken from stand- Polhemus & Polhemus, 2013: 669. ing water habitats at elevations ranging from 30 to 1000 m. Material examined. Cambodia, Kampong Chhnang Prov.: 1 female, Bori Bo, CL 6025. Kampong Speu Prov.: Ranatra cf. gracilis Dallas 2 males, 1 female, Sva Slab, CL 6034; 1 male, 2 females, Ranatra gracilis Dallas, 1850: 10. nr. Rolak, CL 6043. Koh Kong Prov.: 1 male, 1 female, O An Dart, CL 6015; 1 male, Koh Kong–Pursat, CL 6023. Material examined. Cambodia, Kampong Chhnang Pursat Prov.: 1 male, nr. Vealveang, CL 6024. Prov.: 2 immatures, Bori Bo, CL 6025. Koh Kong Prov.: Discussion. The genus Naucoris was last comprehen- 3 immatures, O An Dart, CL 6015; 1 immature, Toeuk sively reviewed for continental Southeast Asia by Pol- Noeng, CL 6020. Pursat Prov.: 2 immatures, nr. Vealveang, hemus & Polhemus (2014). This work provided il- CL 6024. lustrations of the male genitalia for all species known Discussion. All of the immature specimens listed from the region. One other Southeast Asian Naucoris above fall into the gracilis species group based on the species, N. sumatrensis Fieber, is known only from presence of a prominent, conical tubercle on the head the female holotype, apparently from Sumatra, with vertex and a short respiratory siphon. In all of these photographic and line drawing illustrations of that specimens the presence of a median longitudinal ca- type specimen provided by Zettel (2011). rina extending the entire length of the prosternum Ecological notes. Naucoris scutellaris is locally com- indicates that these specimens most likely ­represent mon in lowland streams draining from the Carda- Ranatra gracilis Dallas (see key in Polhemus & mom Mountains. Individuals occur along the mar- Polhemus 2012), but this cannot be verified until gins of pools, often in areas with submerged leaf adult specimens are obtained from these localities. litter. The fact that only immatures were obtained at Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 129 multiple collecting sites during the September 2015 of what is now Papua New Guinea (Lansbury 1985). sampling period, at the start of the rainy season, indi- In his redescription of this species, Lansbury (1985) cates that eclosion and development in this taxon may indicated that the location of Kirkaldy’s type-series be triggered by the onset of the monsoon rains, with was unknown, and based his interpretation instead adults becoming more abundant later in the year. on Australian specimens. The author has now been able to examine a series of 4 brachypterous males and 4 brachypterous females of collected from Family Notonectidae Latreille N. sappho southern New Guinea and bearing the following data: “INDONESIA, Irian Jaya Prov., wetlands in Anisops nigrolineatus Lundblad former Ajkwa River channel near Km 21 on Portsite Anisops nigrolineatus Lundblad, 1933: 145. road, 16 km S of Timika, 15 m elev., water temp. 26.5°C, pH 7.4, 21 January 1997, 10:00–11:00 Material examined. Cambodia, Kampong Speu Prov.: hrs 4°39.91'S, 136°53.83'E, CL 7053, D.A. Polhe- 2 males, nr. Rolak, CL 6042. Kampot Prov.: 9 males, 7 mus coll.”. These specimens, in the collection of the females, Bokor Plateau, CL 6036; 5 males, 11 females, Bo- Bishop Museum, match well with the extensive set kor Plateau, CL 6037. of illustrations for N. sappho provided by Lansbury Discussion. The absence of stout spines on the male (1985), which were presumably based on Australian fore femur, coupled with the unusual structure of specimens, although this is not explicitly stated in the ­stridulatory comb, consisting of a nearly square his paper. grouping of spines set perpendicular to the long axis A comparison of Nychia specimens from Cambo- of the tibia, flanked basally by a smaller fan of spines dia to those from the New Guinea type area reveals set parallel to the long axis, makes this species readily that the structures of the legs and male genitalia recognizable. (Fig. 54) are essentially the same. As such, the Cam- Ecological notes. This species was common in upland bodian specimens are treated under N. sappho for standing water habitats on the summit and flanks the present. However, it is worth noting that certain of the Bokor Plateau, including a deep, still pond morphological differences are present between these (Fig. 10), as well as pools formed amid sandstone populations. In particular the posterior apex of the ledges along steeply dropping streambeds draining frons extends further backward in the Cambodian from the plateau. specimens, such that the holoptic commissure is short and subtends only 5–6 ommatidia, compared Nychia sappho Kirkaldy to a shorter frons and longer commissure that sub- Figs 52–58 tends 8–9 ommatidia in the New Guinea specimens (compare Figs 55, 56). In addition, the posterolateral Nychia marshalli var. sappho Kirkadly, 1901: 809. margin of the hemelytral embolium in brachypter- Nychia marshalli var. atavia Hale, 1925: 17; syn. by ous specimens from New Guinea is weakly concave Lansbury, 1985: 4. and outwardly flared, whereas in Cambodian speci- Nychia malayana Lundblad, 1933: 148; syn. by mens this margin is straight (compare Figs 55, 56). Lansbury, 1985: 4. Finally, there are small differences in the shape and Nychia sappho: Lansbury, 1985: 4. posterior margin of the pronotal foveae when viewed laterally (Figs 57, 58). These differences, however, Material examined. Cambodia, Kampong Speu Prov.: 2 may prove to be no more than intraspecific variation macropterous males, 1 macropterous female, Sva Slab, CL across a broad geographic range when more inter- 6034, D.A. Polhemus (USNM); 1 macropterous female, 1 vening populations are examined, and are not con- brachypterous female, nr. Rolak, CL 6042, D.A. Polhemus sidered sufficient to support delineation of separate (BPBM, USNM); 1 macropterous male, 1 macropterous species at this time. female, nr. Rolak, CL 6043. Kampot Prov.: 1 brachypter- Several other names have been proposed for ous female, Bokor Plateau, CL 6036. Nychia species occurring in Southeast Asia. Lans- Discussion. Nychia sappho as currently interpreted is bury (1985) treated N. malayana Lundblad as a a widespread taxon, with a geographical range ex- synonym of N. sappho, based on a comparison with tending from Australia and New Guinea to South- material from Malaysia, and considered N. infuscata east Asia. Within the known Cambodian notonectid Paiva from Burma and N. limpida Stål from Chi- assemblage, Nychia be recognized by the holoptic na to be unrecognizable due to the relatively brief morphology of the head, in which the inner mar- original descriptions for both species, combined gins of the eyes meet behind the frons (Fig. 52), and with the missing holotype series for the former, and the tufts of long black setae arising from the bases of the badly damaged holotype of the latter. Zettel the fore trochanters (Fig. 53). Kirkaldy’s holotype of (2003) noted that putative populations of N. sappho N. sappho came from Rigo, near the southern coast from the Philippines exhibited a certain degree of Downloaded from Brill.com10/07/2021 06:11:13PM via free access

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Figs 52–53. Nychia sappho, macropterous male, specimen from Cambodia, Kampong Speu Prov., Thom River near Rolak Kong Cheung village, CL 6042. Fig. 52. Dorsal habitus. Fig. 53. Ventral habitus. morphological variation that might warrent further east of Rolak village (CL 6043, Fig. 8); and a deep, taxonomic subdivision, but declined to undertake cold, open pond on the summit of the Bokor Plateau this given the uncertain state of species concepts (CL 6036, Fig. 10). in the genus. Given the equivocal morphological evidence, it seems likely that a molecular systematic Enithares ciliata (Fabricius) study will be necessary to properly constrain species Enithares ciliata Fabricius, 1798: 524. concepts within this genus. Ecological notes. Nychia sappho was taken at multiple Material examined. Cambodia, Kampong Speu Prov.: 1 sites in southwestern Cambodia, at altitudes ranging male, nr. Chambok, CL 6033. from 95 to 985 m. The unifying characteristic of all Discussion. Originally described from India, this is the collecting sites was the presence of standing or a widespread species in tropical Asia, with a range very slowly flowing waters. The habitats from which extending from southward to Ceylon and eastward N. sappho was collected included unshaded, water- through Thailand, Vietnam and Malaysia to Su- filled rock holes in a diabase bedrock exposure along matra (Lansbury 1968). Its collection in Cambodia the margins of the Sva Slab River (CL 6034); heav- logically fills a gap in the previously documented ily shaded overflow channels in gravel parallel to the distribution. main channel of the Thom River (CL 6042); slowly Ecological notes. The single individual taken during flowing, partially shaded pools along a rocky stream the current surveys was netted from the margins of Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 131

Fig. 54. Nychia sappho, intact male genitalia, left lateral view, with major structures labeled; specimen from Cam- bodia, Kampong Speu Prov., stream near Chambok village, CL 6034.

Figs 55–56. Nychia sappho, brachypterous forms, dorsal habitus. 55. Female specimen from Cambodia, Kampong Speu Prov., Thom River near Rolak Kong Cheung village, CL 6042. 56. Female specimen from Indonesia, New Guinea, Papua Prov, nr. Timika, CL 7053.

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Figs 57–58. Nychia sappho, brachypterous forms, lateral view of head and thorax showing form of antennae and lateral pronotal fovea. 57. Female specimen from Cambodia, Kampong Speu Prov., Thom River near Rolak Kong Cheung village, CL 6042. 58. Female specimen from Indonesia, New Guinea, Papua Prov, nr. Timika, CL 7053.

an unshaded pool about 1 m deep along a stream Discussion flowing in a sandy bed through dry semi-deciduous Based on the current surveys, coupled with limited mesic forest with stands of riparian bamboo. previous literature records, a total of 11 families, 38 genera, and 78 species of aquatic Heteroptera Enithares mandalayensis Distant are known to occur in Cambodia, with 68 species Enithares mandalayensis Distant, 1910: 331. known from the area covered by the present study. Of these, six species are putatively endemic to Cam- Material examined. Cambodia, Kampot Prov.: 1 male, bodia, although such a conclusion is provisional, Bokor Plateau, CL 6036. given that freshwater systems across all of Cambo- Discussion. Originally described from Burma, E. dia, much less Indochina as a whole, have not been mandalayensis has also been previously recorded comprehensively surveyed. All of the potentially en- from Thailand, Vietnam, and peninsular Malaysia demic species so far recorded from the country have (Lansbury 1968). As such, its presence in Cambodia come from the Cardamom Mountains and adjacent is not surprising. uplands. Ecological notes. A single individual was taken from Based on current knowledge, Cambodia overall a deep, cool pond on the top of the Bokor Plateau does not have a particularly high degree of faunal en- (Fig. 10), in company with numerous individuals demism in most groups of organisms for which data of Anisops nigrolineatus. The specimen was taken is available. For Odonata, another freshwater insect by scooping the net very deeply into the pond, in- group that is comparatively well surveyed in Cambo- dicating that this species my occupy deeper waters dia, 191 species are currently known, with none en- nearer the benthos, in comparison to the Anisops demic (Kosterin et al. 2012; Kosterin 2014; Kosterin which were abundant in the middle of the water & Chartier 2014; Kosterin pers. comm.). Among column. reptiles and amphibians, 245 species are currently Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 133 known from Cambodia, with only two species, or Program, who kindly provided the services of driver 0.8% of this assemblage, endemic (RGC 2016). Long Kroan and guide Ly Peng La, both of whom Cambodia also supports a remarkably rich freshwa- were exceptionally patient as they shared their deep ter fish biota, with estimates of the number of species knowledge of Cambodia and conveyed the author to ranging from 500 to 1200 (Rainboth 1996, RGC remote locations in the Cardamom Mountains that 2016), but few if any are endemic, with many being he would never have reached otherwise. Similarly, highly migratory on a seasonal basis. the author wishes to convey his gratitude to Pen Rat- In regard to strictly terrestrial faunal groups, 67 tana, of the Vishnu Law Group, who arranged local species of ants are currently known from Cambodia, transport to the Bokor and Kirirom plateaus, and with 16, or 24%, being putatively endemic (RGC provided the author with a working knowledge of 2016). This is a very small number of total ant spe- how to live life in . cies, however, and the fauna is clearly underestimat- In addition, thanks are due to the following indi- ed. The country is known to harbor 601 species of viduals who provided their insights and perspectives birds (RGC 2016), but only are two endemic, repre- on Cambodia, and broadened the author’s under- senting 0.3% of the total. The country also contains standing of its geography, culture and ecology: Sarah a relatively rich assemblage of 100 species of terres- Brook and Rithiny Teng, Wildlife Conservation trial mammals, but none are considered endemic Society Cambodia Program; Kate West, Flora and (RGC 2016). Fauna International; Tracy Crevello, United Nations No endemic plant genera are currently recorded Food and Agriculture Organization; Mark Dubois from Cambodia, although the flora overall is poorly and Kim Heak, World Wildlife Fund; Tray Chantha, surveyed. On the more intensively studied Bokor Srey Sunleang and Kim Nong, Ministry of Environ- Plateau, in the Elephant Mountains behind Kam- ment; and particularly David Ashwell, former repre- pot, the rate of endemism in the upland flora at the sentative from the European Union. species level is around 9% (Dy Phon 1970, 1982), Finally, the author wishes to thank Barbara Pitkin although it should be noted that endemism rates are and Peter Keller at the International Technical As- often higher in isolated montane habitats such as this sistance Program of the United States Department of than in the surrounding lowlands. Across the coun- the Interior, who sponsored his travel to Cambodia try as a whole, the general consensus is that species and allowed him free weekends to explore the aquatic level floral endemism in Cambodia is no more than ecology of the country ancillary to his offical duties. 10% (RGC 2016). Logistical support that allowed the author to com- Based on the above, the apparent 7.7% rate of plete the taxonomic analyses presented in this paper, local endemism in the aquatic Heteroptera biota of in particular use of an AutoMontage digital imag- Cambodia as it is currently known is higher than that ing system, was generously provided by the Bishop exhibited by most other plant and groups in Museum, Honolulu, Hawaii. Access to compara- the country for which data is available. However, it is tive collections was also graciously provided by the likely that at least of some the new taxa described in National Museum of Natural History, Smithsonian the present work, although currently appearing to be Institution, Washington, DC. The author thanks Cambodian endemics, will also prove to be present in these organizations for their continued support of the section of the Cardamom Mountains that extends research related to the systematics and zoogeography into southeastern Thailand. At the same time, these of aquatic Heteroptera. new taxa may well prove to be endemic to the Car- damom Mountains and adjacent plateaus as a whole, References which represent an island of upland habitat isolated from other Indochinese uplifts by the lowlands of Andersen, N.M., 1975. The Limnogonus and Neogerris of the Tonle Sap and Mekong River catchments on the the Old World. — Entomologica Scandinavica, Suppl. north and east, and by the Gulf of Thailand on the 7: 1–96. south. Additional survey work in Cambodia and sur- Andersen, N.M., 1980. Hygropetric water striders of the ge- nus Onychotrechus Kirkaldy with description of a related rounding regions will be necessary to validate this hy- genus (Insecta, , Gerridae). — Steenstrupia pothesis of local endemism, and to clarify its extent. 6: 113–146. Andersen, N.M., 2000. A new species of Tetraripis from Acknowledgments Thailand, with a critical reassessment of the generic classification of the subfamily Rhagoveliinae (Hemip- The surveys in Cambodia upon which the present tera, Gerromorpha, Veliidae). — Tijdschrift voor Ento- report is based could not have been conducted with- mologie 142: 185–194. out the generous help of many other individuals. In Andersen, N.M. & T.A. Weir, 2003. The genus Microvelia particular, the author wishes to thank Bunra Seng Westwood in Australia (Hemiptera: Heteroptera: Veli- of Conservation International’s Greater Mekong idae). — Invertebrate Systematics 17: 261–348. Downloaded from Brill.com10/07/2021 06:11:13PM via free access

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Polhemus, D.A. & J.T. Polhemus, 2012. Notes on Ranatra of a new species from Singapore and neighboring (Heteroptera: Nepidae) from Burma and the Andaman Indonesian islands. — Raffles Bulletin of Zoology 60: Islands, with description of a new species. — Journal 101–107. of the New York Entomological Society 118: 242–251. Tran, A. D. & D.A. Polhemus, 2017. The genus Metroco­ Polhemus, D.A. & J.T. Polhemus, 2013. Guide to the ris Mayr, 1865 (Gerromorpha: Gerridae) in Vietnam, aquatic Heteroptera of Singapore and Peninsular Ma- with descriptions of five new species. — Raffles Bul- laysia. X. Infraorder Nepomorpha — Families Belos- letin of Zoology 65: 109–149. tomatidae and Nepidae. — Raffles Bulletin of Zoology Tran, A.D., C.M. Yang, X.Q. Nguyen & H. Zettel, 2010. 61: 23–43. Faunistical notes on the water measurer Hydrometra Polhemus, D.A. & J.T. Polhemus, 2014. 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A review of the Mountains, Cambodia. — Consultant’s report to Min- genus Rhagadotarsus with descriptions of three new istry of Environment FFI, Cambodia, Phnom Penh, species (Heteroptera: Gerridae). — Raffles Bulletin of 35 pp. Zoology 41: 95–112. Ye, Z., D.A. Polhemus & W. Bu, 2013. A taxonomic con- Polhemus, J.T. & D.A. Polhemus, 1995. Revision of the tribution to the genus Pseudovelia Hoberlandt, 1951 genus Hydrometra Latreille in Indochina and the west- (Hemiptera: Veliidae) from China, with descriptions of ern Malay Archipelago (Heteroptera: Hydrometridae). ten new species. — Zootaxa 3636: 290–318. –— Bishop Museum Occasional Papers 43: 9–72. Zettel, H. 2000. Rhagovelia inexpectata sp.nov., a sibling Polhemus, J.T. & D.A. Polhemus, 2000. The genus species of R. sumatrensis from Southeast Asia (Het- Mesovelia Mulsant & Rey in New Guinea (Heterop- eroptera: Veliidae). — Entomological Problems 31: tera: Mesoveliidae). — Journal of the New York Ento- 175–178. mological Society 108: 205–230. Zettel, H., 2001. Five new species of Perittopus Fieber, Rainboth, W.J., 1996. Fishes of the Cambodian Mekong. 1861 (Hemiptera: Veliidae) from Southeast Asia. — — Food and Agriculture Organization of the United Raffles Bulletin of Zoology 49: 109–119. Nations, Rome, Italy, xi + 265 pp., 27 pl. Zettel, H., 2003. Additional notes on the Aphelocheiri- Raruanysong, S., A. Vithepradit & R.W. Sites, 2014. Key dae, Naucoridae, and Notonectidae (Insecta: Heterop- to the species of Ptilomerinae (Hemiptera: Heterop- tera: Nepomorpha) of the Philippine Islands. — An- tera: Gerridae) of Thailand and review of the fauna of nalen des Naturhistorischen Museums in Wien 104B: the Tennaserim Mountain Range. — Zootaxa 3852: 109–130. 101–117. 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Forest habitats and flora in Lao PDR, und Faunistik der Gerridae mit Neube- Cambodia and Vietnam. — Consultant’s report pre- schreibungen der Gattung Andesenius gen.nov. aus pared for the World Wide Fund for Nature, Indochina der Unterfamilie Ptilomerinae und weiterer Arten Programme Office, Hanoi, 171 pp. (Insecta: Heteroptera: Gerridae). — Entomologische Save Cambodia’s Wildlife, 2006. The atlas of Cambodia: Abhandlungen, Staatliches Museum für Tierkunde National poverty and environment maps. — Save Dresden 57: 149–182. Cambodia’s Wildlife, Phnom Penh, 139 pp. Zettel, H., S. Phauk, S. Kheam & H. Freitag, 2017. Torre-Bueno, J.R. de la, 1925. On some aquatic Hemip- Checklist of the aquatic Heteroptera (Heteroptera: tera from Ceylon, with descriptions of new forms. — Gerromorpha and Nepomorpha) of Cambodia, with Spolia Zeylanica 8 Part 2: 223–234. descriptions of new species of Microvelia Westwood, Tran, A.D. & D.A. Polhemus, 2012. Notes on Southeast 1834 and Ranatra Fabricius, 1790. — Aquatic Insects Asian Ranatra (Heteroptera: Nepidae) with description 38: 1–2, 21–48.

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136 Tijdschrift voor Entomologie, volume 160, 2017

Appendix 1: Revised checklist of aquatic and semi-aquatic Heteroptera of Cambodia

Based on records from Zettel et al. (2017) and the although the occurrence of this taxon may be likely present work. New Cambodia country taxon records in Cambodia, and it has been erroneously listed from from the present paper are marked with an asterisk the country in the past, there is no currently con- (*). New Cambodian provincial records from the firmed Cambodian record. present paper are marked with a hash (#). The checklist does not include Halovelia ber­ grothi Esaki, because as noted by Zettel et al. (2017),

Taxon Provincial distribution

INFRAORDER GERROMOPRHA Family Gerridae Amemboa cambodiana n. sp.* Kampot, Koh Kong, Kampong Chhnang# Amemboa cristata J. Polhemus & Andersen, 1984* Kampong Chhnang# Amemboa javanica Lundblad, 1933* Kampong Speu# Amemboa speciosa J. Polhemus & Andersen, 1984* Pursat# Cylindrostethus costalis Schmidt, 1915 Koh Kong, Siem Reap, Kampong Speu Gnomobates kuiterti Hungerford & Matsuda, 1958* Kampot#, Kampong Speu#, Sihanoukville# Lathriobates johorensis (J. Polhemus & D. Polhemus, 1995)* Kampong Speu#, Sihanoukville# Limnogonus fossarum fossarum (Fabricius, 1775) Phnom Penh, Kampong Speu#, Koh Kong# Limnogonus hungerfordi Andersen, 1975* Koh Kong# Limnogonus nitidus (Mayr, 1865) Phnom Penh, Kampong Speu, Pursat#, Sihanoukville# Limnometra matsudai (Miyamoto, 1967) Siem Reap, Sihanoukville#, Pursat#, Kampot#, Koh Kong# Limnometra octopunctata Hungerford, 1955* Sihanoukville# Metrocoris nigrofascioides Chen & Nieser, 1993 Koh Kong, Kampong Speu Metrocoris tenuicornis Esaki, 1926 Koh Kong Naboandelus signatus Distant, 1910* Kampong Chhnang# Neogerris parvulus (Stål, 1860) Koh Kong, Phnom Penh, Kampong Speu, Kampot# Onychotrechus esaki Andersen, 1980* Kampot#, Koh Kong# Ptilomera hylactor Breddin, 1903 Koh Kong, Pursat# Ptilomera tigrina Uhler, 1860 Koh Kong, Kampong Speu, Sihanoukville# Rhagadotarsus borneensis J. Polhemus & Karunaratne, 1993* Kampong Speu#, Pursat# Rhagadotarsus kraepelini Breddin, 1905* Kampong Speu# Rheumatogonus vietnamensis Zettel & Chen, 1996 Siem Reap, Kampong Speu, Sihanoukville# Ventidius (Ventidioides) karen Lansbury, 1988* Kampong Speu#, Sihanoukville# Ventidius (Ventidius) distanti Paiva, 1918 Kampong Speu, Koh Kong#, Kampong Chhnang#, Pursat#, Sihanoukville# Family Hebridae Hebrus nieseri Zettel, 2004* Pursat# Hebrus cf. polysetosus Zettel, 2004* Kampong Speu# Hyrcanus varicolor Andersen, 1981 Siem Reap Timasius miyamotoi Andersen, 1981 Siem Reap Family Hydrometridae Hydrometra annamana Hungerford & Evans, 1934* Kampong Speu# Hydrometra gilloglyi J. Polhemus & D. Polhemus, 1995 Kampong Speu, Pursat#, Koh Kong# Hydrometra greeni Kirkaldy, 1898 Koh Kong, Kampong Speu Hydrometra jackzewskii Lundblad, 1933* Kampong Speu# Hydrometra longicapitis Torre-Bueno, 1927 Siem Reap, Kampong Speu#, Pursat# Downloaded from Brill.com10/07/2021 06:11:13PM via free access

D. A. Polhemus: Cambodian Aquatic Heteroptera 137

Taxon Provincial distribution

Hydrometra orientalis Lundblad, 1933 Koh Kong, Phnom Penh, Kampong Speu, Kampot# Family Mesoveliidae Mesovelia horvathi Lundblad, 1933* Kampong Speu#, Koh Kong#, Kampong Chhnang#, Pursat# Mesovelia vittigera Horváth, 1895 Phnom Penh, Pursat# Family Veliidae Angilia bispinosa Andersen, 1982* Kampong Speu# Microvelia (Microvelia) bokor n. sp.* Kampot# Microvelia (Microvelia) kohkong n. sp.* Koh Kong# Microvelia (Microvelia) penglyi n. sp.* Kampong Speu#, Koh Kong#, Pursat# Microvelia (Microvelia) setifera n. sp.* Kampong Chhnang#, Pursat#, Koh Kong# Microvelia (Picaultia) douglasi Scott, 1874 Kampong Speu#, Sihanoukville# Microvelia (Picaultia) falcata Zettel et al., 2017 Siem Reap Perittopus asiaticus Zettel, 2001* Kampot# Rhagovelia inexpectata Zettel, 2000 Koh Kong, Kampong Speu, Pursat#, Sihanoukville# Rhagovelia tebakang J. Polhemus & D. Polhemus, 1988* Koh Kong# Strongylovelia albopicta Zettel & Tran, 2004* Kampong Speu#, Koh Kong# Tetraripis zetteli Andersen, 2000* Kampong Speu# INFRAORDER NEPOMORPHA Family Belostomatidae Lethocerus indicus (Lepeletier & Serville, 1825) No precise provincial records Diplonychus rusticus (Fabricius, 1781) Phnom Penh, Kampong Speu# Family Helotrephidae Hydrotrephes maculatus Papácek & Kovac, 2001* Kampong Speu# Idiotrephes asiaticus Papácek & Zettel, 2000 Siem Reap Idiotrephes cf. shepardi Papácek & Zettel, 2000* Koh Kong# Family Micronectidae Micronecta drepani Nieser, 1999 Siem Reap Micronecta guttatostriata Lundblad, 1933* Kampong Speu# Microneca lemnae Nieser, 1999 Siem Reap Micronecta ludibunda Breddin, 1905 Siem Reap Micronecta polhemusi Nieser, 2000* Koh Kong# Micronecta quadristrigata Breddin, 1905 Phnom Penh, Kampong Speu# Micronecta scutellaris (Stål, 1858) Phnom Penh Synaptonecta issa (Distant, 1910)* Kampong Speu#, Koh Kong# Family Naucoridae Heleocoris bengalensis montandoni Lundblad, 1933 Koh Kong, Siem Reap Heleocoris malayensis D. Polhemus & J. Polhemus 2013* Kampong Speu#, Naucoris scutellaris Stål, 1860 Kampong Chhnang#, Koh Kong, Phnom Penh, Kampong Speu# Family Nepidae Cercotmetus asiaticus Amyot & Serville, 1843 Koh Kong Cercotmetus brevipes brevipes Montandon, 1909* Koh Kong# Cercotmetus compositus Montandon, 1903 Kampong Speu Laccotrephes cf. pfeiferiae Ferrari, 1888 Phnom Penh Ranatra cardamomensis Zettel et al. 2017 Koh Kong Ranatra cf. gracilis Dallas, 1850* Kampong Chhnang#, Pursat#, Koh Kong# Ranatra parmata Mayr, 1865 Koh Kong, Siem Reap Ranatra thai Lansbury, 1972 Phnom Penh, Kampong Speu, Kampot#, Sihanoukville# Ranatra varipes Stål, 1861 Phnom Penh, Kampong Speu, Koh Kong Family Notonectidae Anisops breddini Kirkaldy, 1901 Phnom Penh Anisops nigrolineatus Lundblad, 1933* Kampong Speu#, Kampot# Enithares mandalayensis Distant, 1910 Kampong Speu, Kampot# Enithares ciliata (Fabricius, 1758)* Kampong Speu# Downloaded# from Brill.com10/07/2021# 06:11:13PM Nychia sappho Kirkaldy, 1901* Kampong Speu , Kampot via free access

138 Tijdschrift voor Entomologie, volume 160, 2017

Appendix 2: Collecting site data for Vietnamese localities referenced in the text

CL 4297 VIETNAM, Quang Ngai Prov., small rocky stream crossing road on E. side of Via Lac Pass, 109 km NE of Kontum on Hwy 24, 305 m, 14°46'27''N, 108°32'18''E, water temp. 26.5°C, 17 March 2001, D.A. Polhemus, J.T. Polhemus and P. Nguyen. CL 4374 VIETNAM, Bac Thai Prov., Cuc Bo stream, 37 km S. of Bac Kan off Hwy 3, 70 m, 21°52'48''N, 105°45'18''E, water temp. 21°C, 24 March 2000, J.T. and D.A. Polhemus. CL 4384 VIETNAM, Nghê An Prov., Kem waterfall, Pu Mat , S. of Con Cuông, 400 m, 18°58'12''N, 104°48'03''E, water temp. 22°C, 1 April 2000, J.T. Polhemus and P. Nguyen. CL 4387 VIETNAM, Nghê An Prov., Choang River at ford near border of Pu Mat Nature Reserve, S. of Con Cuông, 160 m, 18°59'07''N, 104°50'32''E, water temp. 25.5°C, 2 April 2000, J.T. Polhemus and P. Nguyen.

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