The genus Diolcogaster Ashmead, 1900 (Hymenoptera, Braconidae, Microgastrinae) from China

Abstract The genus Diolcogaster Ashmead, 1900 (Hymenoptera, Braconidae, Microgastrinae) from China is revised and keyed, with nine new species, namely Diolcogaster bifurcifossa sp. n., Diolcogaster brevivena sp. n., Diolcogaster grammata sp. n., Diolcogaster ineminens sp. n., Diolcogaster laetimedia sp. n., Diolcogaster pluriminitida sp. n., Diolcogaster praritas sp. n., Diolcogaster punctatiscutum sp. n. and Diolcogaster translucida sp. n. described and illustrated, and one species, Diolcogaster perniciosa (Wilkinson, 1929) recorded for the first time from China. A key to the Chinese species of this genus is provided.

Remarks. No specimens were available for this study. However, the description of this species by Chen and Song (2004) based on the specimens collected from Fujian is obviously different from that by Telenga (1955). Telenga described this species with mesoscutum coriaceous-rugose, dull; areolet 4-sided; and T1 parallel-sided while Chen & Song stated that this species has the mesoscutum with fine punctures anteriorly but almost smooth posteriorly; areolet 3-sided; and T1 broadening posteriorly. Therefore, the specimens identified by Chen & Song (2004) need further examination.
Head. Rather large, oval in frontal view, with antennal sockets high above middle level of eyes; transverse in dorsal view, 1.6× as wide as long and as wide as mesoscutum, with short white setae all over, including eyes. Ocelli in a very low triangle, the posterior transverse tangent to the anterior ocellus cutting the posterior pair. POL:OD:OOL=7.1:5.0:6.0. Vertex shiny but densely and shallowly punctate, strongly convex, and sharply constricted to occiput; frons virtually without sculpture; face shiny but shallowly rugose, slightly convex, upper half with indistinct median longitudinal carina which is triangularly widened downwards and forms a subtriangular shiny area; width of face 0.6× as high as eye and clypeus combined (19.8:32.2); eyes very large, inner margin of eyes slightly constricted at antennal sockets, widening upwards and downwards, 1.7× as high as wide (30.0:17.9); temple and gena also shiny but shallowly rugose, densely setose. Mouth opening wide, clypeus feebly rugose; tentorial pits of moderate size, distance between tentorial pits 3.6× as long as distance from pit to eye margin (11.0:3.1); malar space very short, 0.2× as long as eye height. Antennae normal, long, with the preapical segment about 2.3× as long as wide; flagellomeres long, thick, with bristly setosity, all flagellomeres with placodes arranged regularly in 2 ranks; apical segment longer than preapical one. Flagellomere proportion: 2 L/W=2.6, 8 L/ W=2.6, 14 L/W=2.2; L 2/14=1.4; W 2/14=1.2.
Mesosoma. Pronotum shiny but sparsely punctate, with a strongly indicated, foveate, ventral furrow laterally. Mesoscutum shiny, evenly and densely punctate, with sparse short setae all over; notauli not impressed. Disc of scutellum shiny, also evenly punctate, its rugose (punctate) tip at middle widely interrupting the posterior, polished band of scutellum, with sparse short setae. Lateral part of the polished band at least distinctly convex anteriorly. Anterior margin of the postscutellum closely applied to the posterior margin of the scutellum so that, laterally, the phragma of scutellum is completely hidden. Scutellar sulcus deep, with few strong longitudinal short carinae, its width 1.3× as long as scutellum (25.0:20.0). Propodeum short, with a strong median keel, shiny beside the median keel on posterior half and anteriorly just behind anterior margin; the area behind the anterior polished area and posterolaterally strongly setigerous punctate; spiracles enclosed by strong costulae. Mesopleuron polished posteriorly and above precoxal sulcus polished; precoxal sulcus long, broad, shallow, punctate. Wings. Forewing with vein r-m reduced to a hyaline point; areolet 3-sided; vein r (1st abscissa of radius) arising from distal 1/2 of pterostigma, far behind the middle, very obliquely placed on the pterostigma; meeting vein 2-SR at a 150 degree angle. Vein 1-R1 (metacarp) with distal end sharply defined, 5.5× as long as its distance from the apex of the marginal cell and 1.1× as long as pterostigma; pterostigma 3.3× as long as wide; r:2-SR:length of pterostigma=14.5:6.0:40.0. Width of 1st discal cell:height of 1st discal cell =31.5:38.0; 1-CU1:2-CU1:m-cu=13.0:12.5:12.5. Hind wing narrow, with edge of vannal lobe beyond its widest part very slightly concave and without trace of a fringe of setae.
Legs. Long. Hind coxa large, flattened on outer side, closely covered with deep punctures, the interspaces very shiny, hardly reaching past posterior margin of T3. Hind tibia swollen toward apex and 0.9× as long as hind tarsus (70.0:80.0). Inner hind tibial spur much longer than outer one, about 0.7× as long as hind basitarsus (23.0:33.0); fourth tarsal segment shorter than fifth tarsal segment (9.0:12.0); apical segment of the front tarsus without a spine. Tarsal claws long, simple.
Metasoma. Shorter than mesosoma. T1 strongly sclerotised, slightly widened posteriorly, with a complete deep and broad median groove which bifurcates apically into two strongly foveate grooves, with smooth surface but setigerous punctate distal to the middle, 1.4× as long as its width and 1.2× as long as T2. T2 with a polished elongated, narrow, parallel-sided median field that is separated from the strongly striate-rugose lateral surface by two broad, deeply foveate grooves; 0. 7× as long as its greatest width and 1.2× as long as T3. T3 as heavily sclerotised as T2, the two tergites together forming a sculptured carapace, beneath which the more apical tergites are completely or partially hidden. T3 subrectangular, with middle of anterior margin slightly arched; very shiny, with surface aciculate, coarsely laterally and weakly medially; the weak but distinct polished median field slightly widened posteriorly and open apically; separated from T2 by a deep foveate groove that is margined along posterior edge of T2. Tergites posterior to T3 membranous, smooth and shiny with very few fine setae. Ovipositor sheath thin and decurved, with sparse long setae posteriorly, without trace of apical, modified setae. Hypopygium large, evenly sclerotised, smooth and without setae, slightly surpassing the last tergite.
Colour. Body bright yellow to black; head brown, except the yellow mouthparts; mesosoma black, but brownish. Flagellum yellowish brown at basal half and darkened to brown apically, scape and pedicel bright yellow, even with antennal socket lightened to yellowish apically. Apex of mandible brown; palpi whitish yellow. Tegula yellow. Fore and mid legs bright yellow. Hind coxa, trochanter and femur also bright yellowish, except the extreme apex of coxa and distal 1/4 of femur brown; hind tibia and tarsi brown except the area distal to the extreme base to the middle of the tibia, the base of basitarsus and the tibial spurs whitish yellow. T1 bright yellow, somewhat transparent, T2 and T3 black, the other tergites and ovipositor sheaths light brown, with posterior margin of tergites more or less transparent, whitish. Wings hyaline but forewing with a faint apical spot; veins brown, vein 1-R1 (metacarp) lightened to yellow, pterostigma evenly brown with extreme base yellowish.
Variation. Body length 2.7-4.2mm, sometimes few tergites posterior to T3 with pale colour. Some individuals from Hainan with pale-colored head and some other individuals with T1 darkened posteriorly.
Male. Same as female.
Distribution. China (Zhejiang, Fujian, Guangdong, Guangxi, Hainan). Remarks. This species is similar to Diolcogaster eclectes (Nixon, 1965), but can be distinguished by the almost smooth surface of T3 beside the median field (the latter has T3 sculptured except for a median, polished area) and the ovipositor sheath without a modified apical seta (the latter with one). Head. Small, subquadrate in anterior view, with antennal sockets high above middle level of eyes; strongly transverse in dorsal view, 1.6× as wide as long and almost as long as mesoscutum, with very short fine setae except the sharply constricted and highly polished area behind lateral ocelli. Ocelli small, in a low triangle, but the transverse, posterior tangent to the anterior ocellus not cutting the posterior pair. POL:OD:OOL=4.0:3.0:7.0. Vertex vey shiny, flattened; frons polished, virtually with- out sculpture; face convex, also very shiny, with sparse fine punctures, feebly transverse striate on upper half, without any trace of median keel, width of face 0.8× as high as eye and clypeus combined (16.6:20.0); eyes small, inner margin of eyes parallel, 1.6× as high as wide (18.0:11.0); temple and gena shiny, densely and finely striate, with appressed longer setae. Clypeus separated from face by a fine curved line linking the tentorial pits, slightly convex and as finely and sparsely punctate as face; tentorial pits small, distance between tentorial pits 2.7× as long as distance from pit to eye margin; malar space short, 0.3× as long as eye height. Antennae much shorter than body, with the preapical segment only 1.2× as long as wide; flagellomeres slightly thickened apically, with bristly setosity, with placodes arranged regularly in 2 ranks; apical segment longer than preapical one. Flagellomere proportion: 2 L/W=3.0 , 8 L/W=1.5, 14 L/ W=1.4; L 2/14=1.8; W 2/14=0.6.

Diolcogaster brevivena
Mesosoma. Pronotum shiny, with a broad ventral furrow laterally. Mesoscutum very shiny, very densely but finely punctate, with posterior margin distinctly rimmed, with dense short fine setae all over; notauli not impressed, only slightly depressed on the posterior imaginary course. Disc of scutellum polished, shiny and at most weakly punctate, with sparse fine setae; polished at tip, so the posterior, polished band of scutellum is continuous. Lateral part of the polished band distinctly convex anteriorly. Anterior margin of the postscutellum closely applied to the posterior margin of the scutellum so that, laterally, the phragma of scutellum is completely hidden. Scutellar sulcus shallow, with few indistinct longitudinal carinae, its width as long as scutellum (13.0:13.0). Propodeum short, shiny, with a strong complete median keel, smooth with very sparse fine punctures, except for very short transverse carina each side along the median keel and dense rugulosity around spiracles. Mesopleuron polished, area behind anterior margin setigerous-punctate; precoxal sulcus only indicated medially by a very shallow depression.
Legs. Long and thin. Hind coxa with dense fine punctures with interspaces smooth and shiny, with dense short fine setae medially and on posterior 1/3; dorsal surface also with dense fine punctures and dense short fine setae. Hind tibia swollen apically and only 0.7× as long as hind tarsus (38.0:49.7), outer surface without spines. Inner hind tibial spur longer than outer one, 0.6× as long as hind basitarsus (13.0:21.9); fourth tarsal segment much shorter than fifth tarsal segment (5.0:7.0); apical segment of the front tarsus without a spine. Tarsal claws simple.
Metasoma. Longer than mesosoma. T1 parallel-sided but roundly constricted distally, surface shiny with anterior 3/4 smooth and posterior 1/4 shallowly rugulose, with sparse fine setae dorsally and laterally; 1.1× as long as its width and 1.5× as long as T2; the percurrent median groove reduced on apex. T2 trapezoid, polished, with a slightly convex median field separated from other parts by two lateral sulci sharply narrowed on anterior half and parallel on posterior half, 0.5× as long as wide and 0.8× as long as T3. Tergites posterior to T2 more membranous, highly polished with a row of short fine setae before posterior margin, except the last two segments scattered with short fine setae. Ovipositor sheath slightly widened apically, decurved, with 2-3 blackened setae at apex. Hypopygium large, evenly sclerotised, polished, with very few long fine setae, apex not surpassing the last tergite.
Colour. Body black, metasoma brownish. Antennae yellowish brown at base and darkened toward apex to brown, pedicel brown. Mouthparts brownish yellow with palpi lighter. Tegula also brownish yellow. Legs almost virtually brownish yellow, except basal 4/5 of hind coxa, apex of hind femur and tibia and apex of claws brown. Tergites of abdomen evenly dark brown, basal sternites transparent and yellowish. Wings hyaline; veins brown, pterostigma, 1-R1(metacarp), submaginal vein and r vein darker.
Variation. Paratype with the same characteristics as holotype, but slightly different in colour pattern.
Male Etymology. The specific name "brevivena" derives from the Latin prefixion "brevi-" and noun "vena", referring to the distinctly short metacarp.

Distribution. China (Yunnan).
Remarks. This species is similar to Diolcogaster minuta (Reinhard, 1880), but can be distinguished by T2 highly polished (the latter with T2 strongly rugose) and vein 1-R1 much longer than its distance from the apex of the radial cell (the latter with 1-R1 vein at most a little longer than its distance from the apex of the radial cell). ( Description. Female. Body length 3.0 mm, fore wing length 3.1 mm. Head. Rather large. Oval in anterior view, with antennal sockets high above middle level of eyes; transverse in dorsal view, 1.5× as wide as long and shorter than that of mesoscutum, shiny with dense short setae all over. Ocelli small in a low, very wide triangle, the transverse, posterior tangent to the anterior ocellus just cutting the posterior pair. POL:OD:OOL=5.0:3.8:7.7. Vertex strongly convex, and sharply constricted to occiput, densely rugose-punctate; frons densely rugose-punctate except the polished area behind scape and pedicel; face coarsely rugose-punctate, without median keel; its width 1.4× as high as eye and clypeus combined (25.6:18.0); eyes of moderate size, inner margins of eyes parallel, 1.8× as high as wide (23.8:13.1); temple and gena striatepunctate. Mouth opening wide; clypeus densely rugose; tentorial pits small, distance between tentorial pits 3.4× as long as distance from pit to eye margin (10.8:3.2); malar space short, 0.2× as long as eye height. Antennae longand with the preapical segment fully 2.5× as long as wide; scape short; flagellomeres thinner, tappered distally, with bristly setosity, with placodes arranged regularly in 2 ranks; apical segment slightly longer than preapical one. Flagellomere proportion: 2 L/W=3.1, 8 L/W=3.2, 14 L/ W=2.0; L 2/14=1.7; W 2/14=1.1.

Diolcogaster chaoi
Mesosoma. Pronotum shiny, with a distinct foveate ventral furrow laterally. Mesoscutum shiny, with uneven, dense puntures or rugose-punctures, more in evidence an- teriorly and along imaginary course of the notauli, with dense short setae all over. Disc of scutellum shiny but densely rugose-punctate, also with dense short setae all over; its rugose tip at middle widely interrupting the posterior, polished band of scutellum, separated from disc by a short transverse keel, with dense short setae. Lateral part of the polished band distinctly broadened anteriorly. Anterior margin of the postscutellum closely applied to the posterior margin of the scutellum so that, laterally, the phragma of scutellum is completely hidden. Scutellar sulcus shallow, with a few short longitudinal carinae, its width 1.1× as long as scutellum (18.0:15.9). Propodeum shiny, coarsely reticulate-rugose except anterior area behind the anterior margin, with a weak median keel. Mesopleuron polished medially, with dense punctures but interspaces shiny; precoxal sulcus broad, indistinct, shallow with few punctures.
Legs. Long and thin. Hind coxa large, shiny with densely punctate surface anteriorly and coarsely reticulate-punctate surface posteriorly, reaching to posterior margin of T3. Hind tibia gradually swollen toward apex and about 0.8× as long as hind tarsus (53.0:69.5). Inner hind tibial spur much longer than outer one and 0.8× as long as hind basitarsus (23.0:30.0); fourth tarsal segment shorter than fifth tarsal segment (9.0:12.0); apical segment of the front tarsus without a spine. Tarsal claws long, simple.
Metasoma. Longer than mesosoma. T1 very long and narrow, linear, parallel-sided, with complete longitudinal groove that is reduced apically, smooth on anterior 1/3 and setigerous punctate on posterior 2/3, 3.1× as long as its width and 2.5× as long as T2. T2 strongly transverse, with a distinctly raised pentagonal median field that is sharply-sided and with smooth and shiny surface, 0.5× as long as its greatest width and 0.7× as long as T3; area beside median field setose, smooth and shiny. Tergites posterior to T2 smooth and shiny, more membranous; only last 3 tergites with a few short fine setae. Ovipositor sheath thin, decurved, with 2-3 blackened setae at apex, long, spatulate. Hypopygium small, evenly sclerotised, smooth and densely setose posteriorly, not surpassing the last tergite.
Colour. Body bright yellow to black; head and thorax black, metasoma almost bright yellow, except the median field of T2 and ovipositor sheaths brown, last 4 tergites light brown medially. Flagellum yellowish brown basally, thickened toward apex, scape and pedicel bright yellow, brownish laterally. Mouthparts yellow, ventral margin of clypeus and mandible brownish; palpi whitish. Tegula whitish yellow. Fore and mid legs bright yellow, whitish basally. Hind coxa and femur black, except the extreme apex of coxa and basal area of femur yellow, trochanter also yellow; hind tibia and tarsus brown except that basal half of tibia and tibial spurs are bright yellow and apical tarsus is yellowish. Wings hyaline; veins brown but greyish on basal half and on metacarp, pterostigma brown, with basal spot grey.
Variation. Paratype with the same characteristics as holotype, but more or less transparent.
Distribution. China (Hunan, Guangdong, Hainan). Remarks. This species is similar to Diolcogaster xanthaspis (Ashmead, 1900), but can be distinguished by the well-defined median field on T2 (the latter with poorly defined median field on T2+T3); 1-CU1 slightly longer than 2-CU1 (the latter with 1-CU1 as long as 2-CU1); and the ovipositor sheath with modified apical setae (the latter without). Head. Oval in anterior view, with antennal sockets high above middle level of eyes; transverse in dorsal view, 1.5× as wide as long and almost as long as mesoscutum, with very dense short setae except the sharply constricted and highly polished area behind lateral ocelli. Ocelli small, in a low triangle, the transverse, posterior tangent to the anterior ocellus just cutting the posterior pair. POL:OD:OOL=6.8:5.0:6.0. Vertex shiny, convex, with distantly discrete large punctures out of ocular area; frons polished and without setae in large part but densely rugose-punctate and setose adjacent to eye margin; face slightly convex, also shiny, densely setigerous-punctate, with an indistinct longitudinal median keel that neither extend to dorsal margin of face nor extend to clypeus, width of face 0.7× as high as eye and clypeus combined (22.7:33.3); eyes large, inner margin of eyes parallel, 1.6× as high as wide (30.0:18.5); temple and gena shiny, densely but finely transversely striate-punctate, with appressed setae. Clypeus densely rugulose, slightly convex; tentorial pits large, distance between tentorial pits 2.5× as long as distance from pit to eye margin; malar space short, 0.2× as long as eye height. Antennae long and thin with the preapical segment more than 1.75× as long as wide; flagellomeres not thickened apically, without bristly setosity, with placodes arranged regularly in 2 ranks; apical segment broken. Flagellomere proportion: 2 L/W=4.6 , 8 L/W=2.6, 14 L/W=1.8; L 2/14=2.1; W 2/14=0.5.

Diolcogaster ineminens
Mesosoma. Pronotum flattened, shiny, with a broad and deep foveate ventral furrow laterally, densely setigerous-punctateabove. Mesoscutum shiny, with very dense and evenly departed punctures, more or less rugose-punctate posteromedially, with dense short setae all over; notauli not impressed. Disc of scutellum also shiny, covex, more densely punctate than mesoscutum, setose; its rugose tip at middle widely inter- rupting the posterior, polished band of scutellum. Lateral part of the polished band distinctly convex anteriorly. Anterior margin of the postscutellum closely applied to the posterior margin of the scutellum so that, laterally, the phragma of scutellum is completely hidden. Scutellar sulcus deep and broad, with few strong longitudinal carinae, its width almost as long as scutellum (24.0:25.0). Propodeum strongly and coarsely rugose, with strong costulae around spiracles, with a strong complete median keel.
Legs. Long and strong. Hind coxa large, shiny, with outer and dorsal surface very densely rugulose-punctate, evenly setose all over; just reaching to anterior margin of T3. Hind tibia swollen medially and then slightly narrowed apically, 0.9× as long as hind tarsus (85.0:93.5), outer surface without spines. Inner hind tibial spurs longer than outer one, 0.5× as long as hind basitarsus (22.0:42.5); fourth tarsal segment shorter than fifth tarsal segment (9.0:14.0); apical segment of the front tarsus without a spine. Tarsal claws simple.
Metasoma. Shorter than mesosoma. T1, T2 and anterior half of T3 strongly sclerotised. T1 parallel-sided, roundly constricted at apex, longitudinally strigous-punctate all over; scattered with appressed setae, denser on posterior 1/4; bearing a distinct median groove with smooth edges; 1.9× as long as its width and 1.2 as long as T2. T2 longitudinally aciculate with interspaces rugose and without setae, without trace of median field, with anterior margin back off each side out of the middle, 0.8× as long as wide and twice as long as T3. T3 subrectangular, with posterior half less sclerotised, also longitudinally aciculate but more finely than T2. Tergites posterior to T3 membranous, polished, sparsely setose. Ovipositor sheath with even width, slightly decurved, without modified apical setae. Hypopygium large, evenly sclerotised, polished with sparse long fine setae apically, apex not surpassing the last tergite.
Colour. Body black, metasoma mostly yellowish brown, more or less transparent. Antennae with scape, pedicel, apical 1/3 of flagellum and outer surface of basal 1/3 of flagellum brown, middle 1/3 and outer surface of basal 1/3 of flagellum white. Labrum dark brown and lightened downwards, labium bright yellow with brown margin, palpi brown. Tegula yellowish brown. Fore and middle legs yellow at base, darkened apically to brown. Hind coxa black, except the reddish apex; trochanter yellow; femur and tibia dark brown except the reddish basal halves; tarsi brown, gradually and slightly lightened apically; tibial spurs whitish yellow. T1 and T2 dark brown, T3 also dark brown anteriorly, then gradually lightened apically to yellowish brown and more or less transparent; apical segment and ovipositor sheaths also brown. Wings hyaline; veins and pterostigma brown, except the basal pale spot of pterostigma.
Variation. Individuals from Fujian with basal 1/3 of flagellum brown just like inner surface.
Male. Unknown. Etymology. The specific name "ineminens" derives from the Latin prefixion "in-" and adjective "eninens", referring to T2 without a raised median field.

Remarks.
This species is similar to Diolcogaster abdominalis (Nees, 1834), but can be distinguished by the ovipositor sheath without modified seta (the latter has ovipositor sheath with a row of four fine black setae, arising from the lower margin); pterostigma emitting radius much distal to middle (the latter with pterostigma emitting radius at most slightly beyond middle); and radial cell of fore wing normal (the latter with radial cell abruptly narrowed apically). Description. Female. Body length 2.9 mm, fore wing length 3.3 mm.

Diolcogaster laetimedia
Head. Rather large, subtriangular in anterior view, with antennal sockets high above middle level of eyes; oval in dorsal view, 1.5× as wide as long and a little longer than mesoscutum, strongly concave behind ocular area, scattered with very short setae except the sharply constricted and highly polished area behind lateral ocelli. Ocelli small, in a low triangle, but the transverse, posterior tangent to the anterior ocellus a little before the posterior pair. POL:OD:OOL=5.3:3.4:4.7. Vertex shiny, convex, ocular area polished, with distantly discrete fine punctures out of ocular area; frons polished and without setae in large part but densely rugulose and setose adjacent to eye margin; face slightly convex, also shiny, densely but shallowly punctate, longitudinal median keel only indicated on dorsal 1/4, width of face 0.7× as high as eye and clypeus combined (19.0:26.8); eyes rather large, inner margin of eyes parallel, 1.6× as high as wide (28.0:17.8); temple and gena shiny, densely but feebly transversely striatepunctate, with dense appressed setae. Clypeus densely rugulose, slightly convex; tentorial pits of moderate size, distance between tentorial pits 2.4× as long as distance from pit to eye margin; malar space very short, only 0.2× as long as eye height. Antennae long and thin, with the preapical segment fully 2.5× longer than wide; flagellomeres Mesosoma. Pronotum shiny, with a shallowly striate ventral furrow laterally, densely and discretely punctate above. Mesoscutum shiny, with very dense and evenly discrete punctures, with dense short setae all over; notauli not impressed. Disc of scutellum also shiny, covex, as densely punctate as mesoscutum; its rugose tip at middle widely interrupting the posterior, polished band of scutellum. Lateral part of the polished band distinctly convex anteriorly. Anterior margin of the postscutellum closely applied to the posterior margin of the scutellum so that, laterally, the phragma of scutellum is completely hidden. Scutellar sulcus deep but narrow, with few strong longitudinal carinae, its width as long as scutellum (16.0:16.0). Propodeum with surface coarsely rugose on anterior 2/3 and polished on posterior 1/3, with strong costulae around spiracles and dull inside, with a very strong complete median keel. Mesopleuron polished above precoxal sulcus but with dense setigerous-punctures anteriorly and below precoxal sulcus; precoxal sulcus indicated by a shallow depression, with few punctures.
Legs. Long and strong. Hind coxa large, reaching to posterior margin of T3, shiny, with dense and evenly discrete punctures, evenly setose all over. Hind tibia swollen apically, 0.8× as long as hind tarsus (58.0:76.0), outer surface with very sparse fine spines. Inner hind tibial spur longer than outer one, 0.5× as long as hind basitarsus (18.0:34.5); fourth tarsal segment shorter than fifth tarsal segment (6.9:10.0); apical segment of the front tarsus without a spine. Tarsal claws simple.
Metasoma. Shorter than mesosoma. T1 slightly narrowed toward apex, shiny, finely rugulose and with distinct median groove on anterior 3/5, densely rugose and with appressed setae on posterior 2/5, 2.0× as long as its width and twice as long as T2. T2 transverse, narrowed apically, anterior corner distinctly projecting anteriorly, longitudinally aciculate with interspaces rugose and without setae, without trace of median field, with very sparse short fine setae, 0.7× as long as wide and as long as T3. T3 subrectangular, very finely longitudinally aciculate, also with very few fine setae. Tergites posterior to T3 membranous, polished, sparsely setose. Ovipositor sheath slightly widened apically, straight, without modified setae at apex. Hypopygium large, evenly sclerotised, polished with sparse long fine setae, apex not surpassing the last tergite.
Colour. Body black, somewhat brownish; metasoma dark brown, lighter and more or less transparent ventrally. Antennae brown except for 3-4 white middle flagellomeres with scape and pedicel transparent ventrally. Mouthparts brownish yellow, ventral margin and apex of labium brown, palpi whitish yellow. Tegula brown. Legs almost brown, with fore and middle legs lighter, except the trochanters, fore and middle coxae and ventral part of hind coxa pale yellow; hind femur yellow at base; tibial spurs whitish yellow. Wings hyaline; veins and pterostigma brown, except the basal pale spot of pterostigma.
Variation. Some individuals from Hainan Island with legs and metasoma lighter coloured, indicated by yellow colour.
Legs. Long and thin. Hind coxa with outer surface densely and discretely punctate with interspaces very shiny, dorsal surface densely rugulose and striate-rugulose, reaching to the middle of T3, setose all over. Hind tibia swollen apically and only 0.8× as long as hind tarsus (48.5:63.8), outer surface without spines. Inner hind tibial spur longer than outer one, 0.7× as long as hind basitarsus (20.0:28.0); fourth tarsal segment almost as long as fifth tarsal segment (7.8:8.0); apical segment of the front tarsus without a spine. Tarsal claws simple.
Metasoma. Longer than mesosoma. T1 strongly sclerotised, narrow, parallel-sided but slightly narrowed distally on posterior half, with few long setae laterally; surface with anterior 3/4 polished and posterior 1/4 rugulose with fine setae, the distinct median groove reduced on posterior 1/4; 2.4× as long as its width and 2.4× as long as T2. T2 polished and without setae, with a slightly swollen median field, ill-defined, 0.4× as long as wide and 0.7× as long as T3. Tergites posterior to T2 membranous, highly polished with a row of short fine setae before posterior margin, except the last segment scattered with short fine setae. Ovipositor sheath with even width, slightly decurved, with 2 blackened setae at apex. Hypopygium of moderate size, evenly sclerotised, polished, with dense short setae all over, apex not surpassing the last tergite.
Colour. Body black, metasoma mostly bright yellow. Antennae evenly brown except scape and pedicel yellow. Mouthparts yellow with palpi whitish. Tegula bright yellow. Fore and middle legs virtually bright yellow. Hind coxa wholly black; trochanter yellow, base of femur and basal 3/4 of tibia also yellow but gradually darkened to brown apically; tarsi and tibial spurs whitish brown. T1 dark brown, the indistinct median field of T2 also brown but lightened outwards to bright yellow, apical 3 segments and ovipositor sheaths also brown, T5, T6 and lateral part of hypopygium brownish. Wings hyaline; veins and pterostigma light brown, somewhat pale.
Variation. Some individuals from Zhejiang and Guizhou have ovipositor sheath only finely setose, without apical modified seta; metasoma mostly yellow, but size of brownish part of dorsal surface and hypopygium variable; the ill-defined median field of T2 hardly impressed in some specimens.

Remarks.
This species is similar to Diolcogaster xanthaspis (Ashmead, 1900), but can be distinguished by the T2 with only ill-defined slightly swollen median field that with even width (the latter T2+3 with distinct but rather poorly defined median field that is slightly wider in front than behind); and propodeum smooth with very few discrete large punctures except very short transverse carina each side along the median keel and dense rugulosity around spiracles (the latter with propodeum coarsely rugose). Description. Female. Body length 3.2 mm, fore wing length 3.5 mm.

Diolcogaster praritas
Head. Oval in anterior view, with antennal sockets high above middle level of eyes; transverse in dorsal view, 1.6× as wide as long and slightly narrower than mesoscutum, with sparse and short setae except the sharply constricted and highly polished area behind lateral ocelli. Ocelli of moderate size, in a low, very wide triangle, the transverse, posterior tangent to the anterior ocellus just cutting the posterior pair. POL:OD:OOL=6.0:3.4:7.0. Vertex and frons smooth and shiny, only between the ocelli and the eye-margin very sparsely punctate; vertex strongly convex; face slightly convex, feebly and transversely striate-punctate, without any trace of median keel, width of face 0.9× as high as eye and clypeus combined (20.0:23.2); eyes small, inner margin of eyes adjacent to face parallel, 1.6× as high as wide (20.5:13.0); temple and gena feebly rugose-punctate and shiny, densely setose. Clypeus slightly swollen, feebly rugose; tentorial pits of moderate size, distance between tentorial pits 2.6× as long as distance from pit to eye margin (10.4:4.0); malar space short, 0.3× as long as eye height. Antennae a little shorter than the body, with the preapical segment about 1.5× longer than wide; scape short; flagellomeres long, thick, without bristly setosity, with placodes arranged regularly in 2 ranks except the distal 6 or 7 segments; apical segment slightly longer than preapical one. Flagellomere proportion: 2 L/W=3.6, 8 L/W=2.5, 14 L/W=2.1; L 2/14=1.4; W 2/14=0.8.
Mesosoma. Pronotum with a very indistinct ventral furrow laterally. Mesoscutum with dense rugose-puctures but interspaces shiny, with short setae all over; notauli not impressed, but indicated by a band of broad depression posteriorly. Disc of scutellum finely, discretely punctate, very shiny, with normal setosity, polished at tip, so the posterior, polished band of scutellum continuous. Lateral part of the polished band at least distinctly convex anteriorly. Anterior margin of the postscutellum closely applied to the posterior margin of the scutellum so that, laterally, the phragma of scutellum is completely hidden. Scutellar sulcus shallow, with few longitudinal carinae, its width almost as long as scutellum (15.0:15.5). Propodeum short, shiny, finely reticulate-rugose all over, with a well-defined median keel. Mesopleuron in large part polished. Precoxal sulcus very short, indicated by a shallow depression with dense but shallow punctures.
Legs. Long and thin. Hind coxa very feebly punctate, almost polished. Hind tibia swollen apically and about 0.8× as long as hind tarsus (55.0:68.2), outer surface without distinct spines. Inner hind tibial spur much longer than outer one, 0.6× as long as hind basitarsus (17.0:30.0); fourth tarsal segment shorter than fifth tarsal segment (7.2:10.0); apical segment of the front tarsus without a spine Tarsal claws simple.
Metasoma. T1 almost parallel-sided, with a shallow median groove over basal 2/3 that with ill-defined sides; dull and coarsely rugose, with long setae laterally and sparse short setae dorsally, 1.4× as long as its width and 1.5× as long as T2. T2 trapezoidal, with a shiny and feebly longitudinally striated raised median field, irregularly shaped but distinctly narrowed behind; the lateral fields striate-rugose, but sculptures reduce toward lateral margin, 1.5× times as wide as long and 1.1× as long as T3. Tergites posterior to T2 highly polished and smooth, more membranous, with short fine setae posterolaterally; setae of metasoma very sparse, almost absent on T3. Ovipositor sheath with 2-3 blackened setae at apex. Hypopygium large, evenly sclerotised, smooth and shiny, with fine setae subapically, with apex a little surpassing the last tergite.
Colour. Body almost black, metasoma yellow on anterior half ventrally and brown dorsally. Antennae light brown at base and darkened toward apex to brown. Clypeus brownish, mouthparts brownish yellow, with ventral margin of mandible brown; palpi whitish yellow. Tegula light brown. Legs almost virtually yellow, except hind coxa brown at extreme base and hind tibia and tarsuli slightly brownish. Tergites dark brown, except lateral margin of T2 and posterolateral corner of T3 yellowish. Tergites posterior to T2 somewhat transparent. Wings hyaline; veins and pterostigma brown, somewhat transparent.
Variation. Paratype distinctly smaller than holotype; T3 yellowish on posterior half and pterostigma broader.
Distribution. China (Zhejiang, Yunnan). Remarks. This species is similar to Diolcogaster austrina (Wilkinsonellus, 1929), but can be distinguished by the disc of scutellum finely, discretely punctate (the latter with disc of scutellum smooth and highly polished); pterostigma shorter than 1-R1 vein (the latter with pterostigma just longer than 1-R1 vein); and TII with surface of the lateral fields besides median field striate-rugose, but reduced toward lateral margin (the latter with the lateral fields besides median field unsculptured). Head. Oval in anterior view, with antennal sockets high above middle level of eyes; transverse in dorsal view, 1.6× as wide as long and almost as long as mesoscutum, with dense short fine setae except the sharply constricted and highly polished area behind lateral ocelli. Ocelli of moderate size, in a low, very wide triangle, the transverse, posterior tangent to the anterior ocellus just cutting the posterior pair. POL:OD:OOL=5.8:4.2:7.5. Vertex vey shiny, with very sparsely discrete punctures, strongly convex; frons polished, virtually without sculpture; face slightly convex, also very shiny, finely but densely punctate, with denser setae, without any trace of median keel, width of face 1.1× as high as eye and clypeus combined (26.8:24.1); eyes small, inner margin of eyes slightly widened downwards, 1.6× as high as wide (22.0:14.0); temple and gena shiny with denser and deeper punctures than vertex, and with longer setae. Clypeus indistinct, slightly convex and as finely and densely punctate as face; tentorial pits large, distance between tentorial pits 3.0× as long as distance from pit to eye margin; malar space short, 0.2× as long as eye height. Antennae longer than body, with the preapical segment fully twice as long as wide; scape short; flagellomeres thinner, tappered distally, without bristly setosity, with placodes arranged regularly in 2 ranks; apical segment longer than preapical one. Flagellomere proportion: 2 L/W=2.5 , 8 L/W=3.1, 14 L/W=2.0; L 2/14=2.1; W 2/14=1.0.

Diolcogaster punctatiscutum
Mesosoma. Pronotum shiny, with a very broad foveate ventral furrow laterally. Mesoscutum very shiny, evenly and densely punctate, with short fine setae all over; notauli not impressed. Disc of scutellum with denser punctures, larger laterally, with interspaces shiny, very densely setose; polished at tip, so the posterior, polished band of scutellum is continuous. Lateral part of the polished band distinctly convex anteriorly. Anterior margin of the postscutellum closely applied to the posterior margin of the scutellum so that, laterally, the phragma of scutellum is completely hidden. Scutellar sulcus deep and broad, with few longitudinal carinae, its width as long as scutellum (15.0:15.0). Propodeum short, shiny, reticulate-rugose all over, coarsely rugose laterally and with strong rugae around spiracles, with a strong complete median keel. Mesopleuron in large part polished (including area below precoxal sulcus posteriorly), the other part with setigerous-punctures. Precoxal sulcus only indicated on anterior half of mesopleuron, shallow and broad, feebly and largely foveate anteriorly and polished behind.
Legs. More or less stout. Hind coxa very shiny, with fine and very sparse punctures and dense short fine setae, inner surface with much shorter setae; rather small, not reaching to T3. Hind tibia swollen apically and 1.1× as long as hind tarsus (49.0:46.3), outer surface with darkened but very indistinct spines. Inner hind tibial spur longer than outer one, 0.8× as long as hind basitarsus (13.0:17.0); fourth tarsal segment much shorter than fifth tarsal segment (5.4:8.9); apical segment of the front tarsus without a spine. Tarsal claws simple.
Metasoma. Broad. T1 parallel-sided or slightly swollen medially, with anterior half surface smooth and shiny and sharply separated from coarsely and strongly reticulaterugose posterior half surface by a strong carina on each side of median groove; the percurrent median groove indistinct on anterior half and sharply rimmed on posterior half, with few long setae in the middle laterally, 1.1× as long as its width, and almost twice as long as T2; T2 transverse, shortened medially, with a raised pentagonal median field, shiny but densely rugulose all over; 2.8× times as wide as long and 1.2× as long as T3. T3 transverse with anterior margin curved, shiny with very fine rugulosity and a few short fine setae. Tergites posterior to T3 more membranous, highly polished with a row of short fine setae bordering anterior margins except for the last two segments which only have sparse short fine setae. Ovipositor sheath with even width, with a fine modified apical seta. Hypopygium large, evenly sclerotised, smooth and shiny, with long fine setae, apex slightly surpassing the last tergite.
Colour. Body dark brown to black, except metasoma yellow with brown apex. Antennae light brown at base and darkened toward apex to brown. Mouthparts lighter with mandible yellow and palpi white. Tegula whitish yellow. Legs almost virtually yellow, except apical 1/3 of hind tibia and apex of claws brown and hind basitarsus slightly brownish. Tergites almost yellow and somewhat transparent, except middle of T3 to T6 and hypopygium, T7, posterior half of T8, the last tergite and ovipositor sheaths brown. Wings hyaline; veins brown, pterostigma dark.
Distribution. China (Guangdong). Remarks. This species is similar to Diolcogaster austrina (Wilkinsonellus, 1929), but can be distinguished by the disc of scutellum with dense punctures, larger laterally (the latter with disc of scutellum smooth and highly polished); vein 1-CU1 much shorter than vein 2-CU1 (the latter with vein 1-CU1 and vein 2-CU1 of equal length); and antennae normal, long and thin (the latter with antennae short and stout). ( Description. Female. Body length 3.0 mm, fore wing length 3.4 mm. Head. Rather large, oval in anterior view, with antennal sockets high above middle level of eyes; strongly transverse in dorsal view, 1.4× as wide as long and 0.8× as long as that of mesonotum, with short white setae including eyes. Ocelli in a low, very wide triangle, the transverse, posterior tangent to the anterior ocellus just cutting the posterior pair. POL:OD:OOL=7.1:3.8:8.0. Vertex densely rugose, strongly convex and sharply constricted to occiput, with very short dense fine setae; frons also densely rugose; face slightly convex, rugose and setose, upper half with very indistinct median longitudinal carina, width of face 0.8× as high as eye and clypeus combined (15.0:27.2); eyes of moderate size, inner margins of eyes slightly narrowed downwards, 1.8× as high as wide (27.2:15.0); temple and gena feebly rugose-punctate and shiny, densely setose. Clypeus also rugose and setose; tentorial pits small, distance between tentorial pits 2.8× as long as distance from pit to eye margin (12.8:4.6); malar space short, 0.2× as long as eye height. Antennae slightly longer than body, with the preapical segment about thrice as long as wide; flagellomeres with bristly setosity, with placodes arranged regularly in 2 ranks except the apical one; apical segment subequal to preapical one in length. Flagellomere proportion: 2 L/W=2.9, 8 L/W=2.5, 14 L/ W=2.3; L 2/14=1.6; W 2/14=1.3.

Diolcogaster spreta
Mesosoma. Pronotum with two weakly indicated but distinct foveate furrows laterally. Mesoscutum shiny, evenly and densely rugose-punctate, with short setae all over; notauli not impressed. Disc of scutellum as strongly sculptured as the mesoscutum, with normal setosity, its rugose tip at middle widely interrupting the posterior, polished band of scutellum. Lateral, polished field reduced to a thin, parallel-sided strip. Ante-rior margin of the postscutellum closely applied to the posterior margin of the scutellum so that, laterally, the phragma of scutellum is completely hidden. Scutellar sulcus deep, with few longitudinal carinae, its width 0.9× as long as scutellum (19.0:20.4). Propodeum shiny, with a complete median keel; surface on each side of the median propodeal keel almost smooth, with dense obsolescent punctures, only with very short transverse ridging on immediate vicinity of longitudinal carina. Mesopleuron polished posteriorly and above precoxal sulcus, depressed below and there densely setigerouspunctate; precoxal sulcus long, broad, shallow with shallow longitudinal carina.