Introduction
Currently, the fairyfly genus Cosmocomoidea Howard (Hymenoptera: Mymaridae) contains 82 described, valid species including 79 extant taxa (Huber 2015) from around the world except for the Afrotropical and Australasian regions (Triapitsyn et al. 2010; Huber 2015) . It is far more diverse and speciose in the Neotropical region (Triapitsyn et al. 2010) than in the Old World. Its only confirmed previous records from mainland China (Beijing Municipality) were those of C. kodaiana (Mani & Saraswat) and C. ?latipennis (Girault) by Triapitsyn (2013a) , as Gonatocerus (Cosmocomoidea) ?kodaianus (Mani & Saraswat) and G. (Cosmocomoidea) ?latipennis Girault, respectively. Triapitsyn & Shih (2014) also recorded a Cosmocomoidea sp., as Gonatocerus (Cosmocomoidea) sp., from eggs of the leafhopper Kolla paulula (Walker) (Hemiptera: Cicadellidae) in Taiwan.
Because China is situated in two ecozones, the Palearctic (northern provinces) and Oriental (southern provinces), any study of its fairyfly fauna requires good knowledge of at least the fauna of the entire Eurasia but preferably of the entire Old World. Fortunately, the revisions of Zeya & Hayat (1995) of the Indian species and of Triapitsyn (2013a) of the Palearctic species of Gonatocerini have made it possible for us to identify most Chinese species with confidence, although recent random descriptions of several taxa (not in a revisionary context) in India have made some identifications more challenging.
The history of taxonomic and biological studies of Mymaridae in China was overviewed by Lin (2002) . Specimens of Gonatocerini (as Gonatocerus Nees ab Esenbeck) from China can be identified to genus using the key in Lin & Xu (2000) , and those of Cosmocomoidea using the key in Huber (2015) . In this communication we describe for China two new Cosmocomoidea species, provide three new species records, and key the seven known species.
Material and methods
All specimens studied were collected by sweeping. The specimens from Xinjiang, Hubei and Guangxi are deposited mostly in the insect collection of College of Life Science and Technology, Urumqi, Xinjiang, China (ICXU), but also a few in the Entomology Research Museum, Department of Entomology, University of California, Riverside, California, USA (UCRC). The other specimens, which were borrowed from the Fujian Agriculture and Forestry University, Fuzhou, Fujian, China (FAFU), had been previously sorted to morphospecies by Mei Xu (Xu 2002) under Gonatocerus (s.l.) . In the course of this study we re-identified these according to recent advances in the knowledge of the genus.
All measurements were taken from slide-mounted specimens at 100×, 200×, or 400× magnification with an Olympus biological microscope and an eyepiece reticle. Photographs were taken from slide-mounted specimens using a Nikon Ni-E system, and images were processed using Adobe Photoshop.
Terminology for morphological features mainly follows Triapitsyn et al. (2010) , Triapitsyn (2013a) and Huber (2015) . Abbreviations used are mps, multiporous plate sensillum (longitudinal sensilla, of authors) on the antennal flagellar segments (Triapitsyn 2013a) , and F, funicle segment of the female antenna or flagellomere of the male antenna. Redescriptions of previously described species are based on specimens from China. In the descriptions of the new species, a measurement or a ratio of the holotype is followed by the respective range of the paratypes. In the lists of the examined material, for clarity full names of the Chinese collectors are given in parentheses, with the last names first, when they are first mentioned. Diagnosis. Specimens of most species are relatively large for fairyflies, average body length more than 1 mm; subantennal sulci strongly convergent and close together at mouth margin; ocellar triangle with 2 setae; female antenna with funicle 8-segmented; pronotum divided into two abutting lobes; dorsellum triangular to rhomboidal; propodeum with two submedian carinae; fore wing often with a large bare area behind marginal vein. Cosmocomoidea was erected by Howard (1908) with C. morrilli Howard as its type species. Annecke & Doutt (1961) classified it as a subgenus under Lymaenon Walker. Both Matthews (1986) and Huber (1988) treated Cosmocomoidea as the ater species group of Gonatocerus. Zeya & Hayat (1995) revised the Indian species of Cosmocomoidea also within the ater-group of Gonatocerus, as did Zeya & Khan (2012) and Manickavasagam & Rameshkumar (2013) . Triapitsyn et al. (2010) and Triapitsyn (2013a, b) classified Cosmocomoidea as a subgenus under Gonatocerus and reviewed its species from the Neotropical, Palaearctic, and Nearctic regions, respectively. Huber (2015) divided Gonatocerus into several genera within the tribe Gonatocerini. In his classification, which we follow here, Cosmocomoidea is regarded as a valid genus, though phylogenetic relationships among the closely related genera of Gonatocerini remain largely uncertain and may require a combined morphological and molecular analysis to resolve them more clearly.
Key to species of Cosmocomoidea in China (females) 1 Ovipositor markedly exserted beyond apex of gaster ( 4(3) Funicle segments relatively short and broad (Fig. 5) ; propodeum ( Fig. 6) Antenna ( Fig. 1 ) with radicle 0.2-0.3× total length of scape, rest of scape 2.35-3.45× as long as wide; pedicel much longer than F1; F1 and F2 subequal in length and the shortest funicle segments, F3 slightly longer than F4, F4 shorter than the following funicle segments, F5-F8 more or less subequal in length; mps on F3 (1), F4 (1), F5 (2), F6 (0 [or 1 on one antenna]), F7 (2) and F8 (2). Clava with 8 mps, 2.3-3.5× as long as wide. Mesosoma slightly shorter than metasoma. Propodeum (Fig. 2) usually with complete submedian carinae narrowing anteriorly and usually joining together at anterior margin of propodeum but sometimes qthomas@example.org. Fore wing (Fig. 3) 2.5-2.7× as long as wide; longest marginal seta 0.1-0.2× maximum wing width; disc with a slight brownish tinge and bare behind venation except for 3 or more setae behind stigmal vein, and densely setose elsewhere. Hind wing 13.6-17.5× as long as wide; disc unevenly setose, with a slight brownish tinge; longest marginal seta 1.6-1.8× maximum wing width.
Ovipositor (Fig. 4) occupying 0.9-1.0× length of gaster, not or at most barely exserted beyond the apex of gaster, 1.1-1.5× as long as mesotibia.
MALE. Unknown from China but known from other countries (Triapitsyn 2013a) . Distribution. For C. atra s.l., Holarctic and Oriental (Zeya & Hayat 1995; Triapitsyn 2013a) ; China (new record, both Palearctic and Oriental parts).
Hosts. Unknown for C. atra s.str. but see host records and discussion in Triapitsyn (2013a) for C. atra s.l. Comments. We identify specimens from China as C. atra s. l. because they do not exactly agree with the lectotype in the shape of the propodeal carinae but fit Matthews' (1986) and Zeya & Hayat's (1995) Redescription. FEMALE. Body length 950-1375 µm. General color brown to dark brown; head and mesosoma dark brown; scape, pedicel, and gaster brown; legs light to dark brown. Antenna (Fig. 5 ) with radicle 0.1-0.2× total length of scape, rest of scape 2.6-3.8× as long as wide; pedicel much longer than F1; F2 shorter than the following funicle segments, F3-F7 more or less subequal in length and a little longer than F8; mps on F2 (1), F3 (usually 2, occasionally 1 on one antenna), F4-F8 (2 on each); clava with 8 mps, 3.6-4.7× as long as wide.
Mesosoma slightly longer than metasoma. Propodeum ( Fig. 6 ) with submedian carinae complete or almost complete, slightly curving anteriorly. Fore wing (Fig. 7) 2.65-3.1× as long as wide, longest marginal seta 0.1-0.2× maximum wing width, disc with a brownish tinge throughout, bare behind venation except for at least 8 setae behind stigmal vein. Hind wing about 16.5× as long as wide; disc almost hyaline, with a row of setae along each margin and additional setae at the base and apex; the longest marginal seta about 2.0× maximum wing width.
Ovipositor ( Fig. 8) Redescription. FEMALE. Body length 1426-1465 µm. Body brown to dark brown; antennal flagellum dark brown, radicle and scape yellow, pedicel yellowish brown to brown; legs yellowish brown.
Antenna ( Fig. 9 ) with radicle about 0.2× total length of scape, rest of scape 3.6-3.9× as long as wide; pedicel slightly longer than F1; F1 the shortest funicle segment, F2-F7 subequal in length; mps on F2 (1) and F3-F8 (2 on each); clava long, with 8 mps, 5.2-5.6× as long as wide.
Mesosoma shorter than metasoma. Propodeum ( Fig. 10 ) with well-developed submedian carinae extending to anterior margin and not connecting to each other. Fore wing (Fig. 11) 3.0-3.2× as long as wide, longest marginal seta 0.1-0.2× maximum wing width, with disc slightly infumate throughout, mostly bare behind venation except for a few setae behind stigmal vein. Hind wing 14.0-18.0× as long as wide.
Ovipositor ( Fig. 12 ) occupying 0.6-0.9× length of gaster, not exserted beyond its apex, about as long as mesotibia.
MALE. Unknown.
FIGURES 9-12. Cosmocomoidea kodaiana ♀ (Jiangle, Fujian): 9, antenna; 10, propodeum; 11, fore wing; 12, ovipositor.
Redescription. FEMALE. Body length 1059-1400 µm. General body color black; antenna dark brown; legs yellowish brown except coxae, metafemur and metatibia black, and mesofemur and two apical segments of tarsi brown.
Antenna ( Fig. 13 ) with radicle 0.1-0.2× total length of scape, rest of scape 2.8-4.3× as long as wide; pedicel much longer than F1; F1 the shortest funicle segment, F3 longer than F2 and F4, F3 and F5 subequal in length (the longest funicle segments), the following funicle segments usually progressively slightly shorter than preceding ones; mps on F3 (2), F4 (0 or 1), F5 (usually 2, occasionally 1 on one antenna), F6 (1 or 2), F7 (2) and F8 (2); clava with 8 mps, 3.8-5.0× as long as wide. Mesosoma shorter than metasoma. Propodeum ( Fig. 14) with submedian carinae complete, curving anteriorly and posteriorly. Fore wing (Fig. 15) 2.8-3.4× as long as wide, longest marginal seta 0.1-0.2× maximum wing width, disc with a brownish tinge throughout, mostly bare behind venation except for a few setae behind stigmal vein, and densely setose elsewhere. Hind wing 24-25× as long as wide.
Ovipositor ( Fig. 16 ) occupying 0.7-0.9× length of gaster, not exserted beyond its apex, 0.9-1.4× as long as mesotibia.
MALE. Body length 1075 µm. Color and size similar to female. Antenna (Fig. 17) with F1 1.3× as long as wide. Fore wing 3.3× as long as wide. Genitalia (Fig. 18 ) about 0.6× length of gaster.
Distribution. Holarctic (Triapitsyn 2013a) , who also recorded Gonatocerus ?latipennis from the Palearctic part of mainland China, Japan, Far East of Russia, and from the high altitude area in Taiwan which is an outpost of the Palearctic fauna, although most of the island is within the Oriental ecozone.
Hosts. Unknown. Comments. We identify the specimens from China only tentatively as G. ?latipennis because the possibility exists that they may represent an undescribed species that is very difficult to distinguish morphologically from the real G. latipennis . Two females from Baoji, Shaanxi, have F8 of the antenna relatively longer and in one specimen from Ningshan, Shaanxi, the funicle is deformed, with F5 partially fused to F6.
Cosmocomoidea oxypygus (Foerster, Redescription. FEMALE. Body length 1230-1370 µm. Body darkish brown to black. Antenna ( Fig. 19 ) with radicle about 0.3× total length of scape, rest of scape 2.0-2.4× as long as wide; pedicel longer than F1; F1 the shortest funicle segment, F3 a little longer than F2 or F4, F5 the longest funicle segment, following funicle segments usually progressively slightly shorter than preceding ones; mps on F5 and F6 (1 each), F7 and F8 (2 each); clava with 8 mps, 2.4-3.7× as long as wide.
Mesosoma shorter than metasoma. Propodeum ( Fig. 20) with fine, subparallel submedian carinae close to each other and usually not extending to anterior margin. Fore wing (Fig. 21 ) about 2.8× as long as wide; longest marginal seta about 0.2× maximum wing width; disc almost hyaline, bare behind venation except for 2 setae just behind stigmal vein. Hind wing 12.5-15.3× as long as wide; disc almost hyaline; longest marginal seta 1.4-2.0× maximum wing width.
Ovipositor (Fig. 22) long, occupying entire length of gaster and markedly exserted beyond its apex, 2.9-3.3× as long as mesotibia.
MALE. Unknown from China. Distribution. Holarctic (Triapitsyn 2013a) 

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