Lectotype (hereby designated): dissected male (BMNH): “LACTHO / Tonkin. / de Cooman // Andrewes / Bequest / B. M. 1922-22 // Omicrogiton / coomani Paratypes! / J. Balfour-Browne det. // A. d’Orchymont det. / Omicrogiton / insularis / d’Orchymont // Coll. d’Orchym.”. Paralectotypes: 1 unsexed spec. (BMNH): same data as the lectotype [this specimen was originally pinned on the same pin as the lectotype, and is now moved to the seperate pin to whoch copies of the aforementioned label are attached]; 1 unsexed specimen (BMNH): “ LACTHO / Tonkin. / de Cooman // C. G. Champion / Brit. Mus. / 1925-42 // A. d’Orchymont det. / Omicrogiton / insularis / d’Orchymont // PARATYPE // Omicrogiton / coomani Type! / J. Balfour-Browne det.”; 1 unsexed specimen (BMNH): “ LACTHO / Tonkin. / de Cooman // C. G. Champion / Brit. Mus. / 1925-42 // A. d’Orchymont det. / Omicrogiton / insularis / d’Orchymont // Omicrogiton / coomani Paratype! / J. Balfour-Browne det.”.

Figures 1–6. 

General habitus of Chinese Omicrogiton Orchymont, 1919 and Mircogioton Orchymont, 1937 1–2 O. roberti sp. n. in dorsal and ventral view 3 Lectotype of O. coomani Balfour-Browne, 1939, dorsal view 4 Paralectotype of O. coomani, ventral view 5–6 M. coomani Orchymont, 1937, dorsal and ventral view.

CHINA: Guangdong: 3 males, 4 females, 87 unsexed spec. (SYSU): Zhaoqing, Heishiding Natural Reserve, 4–6.x.2013, Fenglong Jia, Ye Jia, Bingjie Chen, Renchao Lin et Weilin Xu leg.; 2 males, 2 females, 15 unsexed spec. (SYSU): Fengkai, Heishiding Natrual Reserve, 179 m, 12.v.2011, Song Keqing leg.; 138 spec. (SYSU): Fengkai, Heishiding Natural Reserve, 20.xi.2010, Fenglong Jia leg.; 88 spec. (SYSU): Fengkai, He’erkou, in decaying banana trunks, 14.viii.2010, Fenglong Jia leg.; 14 spec. (SYSU): Fengkai, Heishiding Natural Reserve, 2.v.2011, Fenglong Jia leg.; 2 males, 1 female, 44 spec. (SYSU): Fengkai, Guangling village, 9.x.2010, Yan Mei, Lijun Yang, Yali Yu leg.; 1 male (SYSU): Fengkai, Yanshuitian, 8.x.2010, Yan Mei et Lijun Yang leg. 1 male, 11 unsexed specimens (NMPC): W of Qixing, Heishiding nature reserve, rotting trunks of banana along the dried-up stream in the primary lowland forest, 190-260 m a.s.l., 23°27.9'N 111°54.3'E, 1.–3.v.2011, Fikáček & Hájek leg. Hainan: 1 male (NMPC): Limushan Mts., 19°9.1–9.2'N 109°45–46'N, along the road, 550–750 m a.s.l., rotting banana trunks at the stream in secondary forest, 5.v.2011, Fikáček & Zhao leg. Hong Kong: 2 males, 3 females, 25 unsexed spec (AFCD): Hong Kong, Wutongzhai, 27.ix.2013, F.L. Jia, Yingming Lee & Eric Chen leg. VIETNAM: 2 males (SYSU): Tonkin, Hoa-Binh, leg. A. de Cooman, with labels “Omicrogiton insularis d’Orchym.” [handwritten] and “En-121415 [En-121416, respectively], Sun Yat-sen University, Biomuseum” [transcript from Chinese]; 1 male, 1 female (IZCAS): Tonkin, Hoa-Binh, leg. A. de Cooman.

Body length 1.9–2.1 mm, width 1.2–1.3 mm. Head and elytra brown; scapus ca. 3.5× as long as antennomeres 2–5 combined. Interstices of pronotum with fine mesh-like microsculpture; prosternum strongly tectiform. Phallobase ca. half as long as parameres, without distinct manubrium; paramere without strongly sclerotized S-shaped portion, rather wide throughout, weakly sinuate on outer margin, apex semicircular; median lobe slightly narrower than paramere, wide basally, then abruptly narrowing and rather narrow in apical half, apex narrowly rounded, gonopore small, apical.

Omicrogiton coomani differs from all other species of the genus except of O. cheesmanae from New Hebrides by the presence of the fine microsculpture on pronotal interstices. It may be also easily distinguished from all other species of the genus by the morphology of the aedeagus, which lacks the strongly sclerotized S-shaped sclerite of the paramere, and has narrow median lobe with small apical gonopore.

When Balfour-Browne (1939) checked the material of Omicrogiton insularis Orchymont, 1919 deposited in BMNH, he found that the specimens from “Tonkin (Lac Tho)” (i.e. Lac Tho in the Hoa Binh Province in northern Vietnam) differ from those from Engano Island near Sumatra (type locality of O. insularis) and described them under the name O. coomani. Since the diagnosis of O. coomani was very short and it was only presented in the discussion concerning another species of the genus from New Hebrides, the species remained virtually unknown and unrecognized in the collections. The aedeagus of the dissected type specimen of O. coomani (Fig. 17) really differs from that of O. insularis and we can therefore confirm that O. coomani is a separate species.

Within this study, we are showing that O. coomani may co-occur syntopically with other species of the genus, from which it may be distinguished by male genitalia only. To fix the identity of the species and prevent any future confusion, we are hence designating here the only dissected syntype specimen as the lectotype of O. coomani. Aedeagus of this specimen is shown in Fig. 17.

All examined specimens were found in the decaying banana trunks, typically in still standing trunk bases which are decaying after the apical part of the plant was cut or broken.

China (Guangdong, Hong Kong), northern Vietnam. New for China.

Holotype: male (SYSU): CHINA: Hainan Isl.: Limushan Mts., 19°9.1–9.2'N, 109°45-46'N, along the road, 550–750 m a.s.l., rotting banana trunks at the stream in secondary forest, 5.v.2011, Fikáček & Zhao lgt. Paratypes: 2 males (SYSU, NMPC): same locality as the holotype; 2 males (NMPC): China: Hainan Isl.: Jianfengling Mts., Tiachi Lake env., Bishu villa, rotting banana trunk at the bank of a drying-up stream in the primary forest above the hotel area, 18°44.7'N 108°50.7'E, 950 m a.s.l., 9–11.v.2011, Fikáček, Kubeček & Li lgt.

Body length 1.9–2.0 mm. Head and elytra brown; scapus ca. 3.5× as long as antennomeres 2–5 combined. Interstices of pronotum without microsculpture; prosternum weakly tectiform. Phallobase ca. as long as parameres, wide anteriorly, with wide rounded manubrium; paramere with strongly sclerotized S-shaped portion and membranous mesal and apical portions, sclerotized parts of left and right paramere forming very obtuse angle basally; median lobe narrower than phallobase and paramere, rather wide basally, gradually narrowing towards apex, apex rather widely rounded, gonopore subapical (Fig. 15).

Form and Color. Body oval, weakly convex, length 1.9–2.0 mm, width 1.2 mm. Head, pronotum and elytra brown; lateral margin of elytra paler than disc; labrum, maxillary palpomeres and antennomeres 1-6 reddish brown, antennal club of antennae slightly paler; ventral surface brown, legs reddish brown.

Head. Clypeus with fine punctures, interstices without microsculpture; lateral deflexed extensions not defined from clypeal disc by ridge; anterior margin with narrow marginal bead laterally. Frontoclypeal suture undetectable. Frons with sparser and coarser punctures than on clypeus, interstices without microsculpture. Eyes small, clearly protruding, interocular distance ca. 5× as wide as one eye in dorsal view. Labrum exposed, sinuate on anterior margin. Mentum dull, densely granulate, without punctures, ca. 2× as wide as long, not depressed anteromedially, anterior margin slightly protruding medially. Submentum declined below the level of mentum. Antenna with 9 antennomeres, scapus ca. 3.5× as long as antennomeres 2–5 combined, club compact, last club antennomere the widest. Maxillary palpomere 2 moderately swollen, palpomere 4 almost symmetrical, widest at midlength, equal in length to palpomere 2, longer than palpomere 3.

Thorax. Pronotum ca. 2.6× as wide as long. Pronotal punctation similar to that on frons, interstices without microsculpture. Lateral margins with strong bead overlapping to anterior margin, posterior margin of pronotum without bead. Prosternum weakly tectiform; antennal grooves absent. Mesoventrite strongly and abruptly raised medially to form a narrow longitudinal lamina not reaching metaventral process posteriorly; cavities for reception of procoxae absent. Metaventrite weakly convex, without glabrous median portion, with weak posteromedial depression on elevated portion. Elytra widely explanate laterally, with 10 series of large punctures, series 1–5 almost reaching base, series 6–10 abbreviated anteriorly; interval punctures very fine but distinct, similar to those on pronotum, interstices without microsculpture; humeral bulge absent; lateral margin of elytron finely serrate; epipleuron wide throughout. Profemur glabrous, anterior margin angulate near base, with a large basal depression with golden pubescence, tibial groove sharply defined. Mesofemur with sparse and coarse punctures on anterior half, each puncture with a short seta; posterior half glabrous, with fine longitudinal sculpture. Metafemur with fine longitudinal sculpture and scattered fine punctures. Tibiae flat, meso- and metatibiae with long and stout spines along outer face and 1 or 2 pairs of spines on apical half of inner face; metatibial long spur ca. as long as first metatarsomere. First metatarsomere almost as long as metatarsomeres 2–3 combined.

Abdomen. Abdomen with five ventrites; first ventrite not longer than ventrites 2–5 each; first ventrite without median longitudinal carina, fifth ventrite narrowly rounded, not emarginate apically.

Male genitalia. Phallobase ca. as long as parameres, wide anteriorly, with wide rounded manubrium; paramere with strongly sclerotized S-shaped portion and membranous mesal and apical portions, membranous apex of paramere widely rounded; sclerotized parts of left and right paramere forming very obtuse angle basally; median lobe narrower than phallobase and paramere, wide basally, gradually narrowing apicad, apex rather widely rounded, gonopore subapical (Fig. 15).

Omicrogiton hainanensis sp. n. belongs to the species with strongly sclerotized S-shaped portion of the paramere, together with the Oriental O. insularis Orchymont, 1919 and O. gomyi Bameul, 1986 from the Reunion Island (Bameul 1986). It differs from O. insularis by the much wider aedeagus (aedeagus is generally very narrow in O. insularis (Fig. 19), much wider parameres with bases of strongly sclerotized parts forming a very obtuse angle (parameres are narrow and bases of sclerotized portions form acute angle in O. insularis) and wide median lobe with subapical gonopore (median lobe is extremely narrow apically and the gonopore is situated at midlength in O. insularis). The aedeagus of O. gomyi is similar to that of O. hainanensis in the proportions (i.e., it is wide and robust in both species), but O. gomyi easily differs by wide median lobe with apical gonopore. Omicrogiton coomani and O. roberti, differ from all above species including O. hainanensis in parameres lacking the strongly sclerotized S-shaped portion, and O. coomani and O. cheesmanae may be distinguished from other species including O. hainanensis by the pronotum with fine mesh-like microsculpture.

The species name is patronymic, referring to the Hainan Island where this species is commonly collected.

All type specimens were collected in decaying banana trunks in primary or secondary rainforests. On the type locality, the specimens of this species were collected in the same banana trunk as two other Omicrogiton species occurring in Hainan (i.e. O. roberti sp. n. and O. coomani), which indicates that multiple species may occur syntopically in this genus. For this reason, we excluded females from the type series of this species.

China (Hainan).

Holotype: male (SYSU): CHINA: Hainan isl., Limushan Mts., Limu temple, 5.v.2011, 19°9.1–9.2'N, 109°45–46'E, 550–750 m; along the road, rotting banana trunks at the stream in secondary forest, Fikáček & Zhao lgt.

Body length 2.1 mm. Head and elytra black or dark brown; pronotum paler than head and elytra. Scapus ca. 2.5× as long as antennomeres 2–5 combined. Prosternum strongly tectiform, with low longitudinal carina medially. Phallobase much shorter than parameres, with thin and long basal manubrium; paramere without distinct S-shaped more sclerotized portion, narrow, weakly curved on outer margin, rounded apically; median lobe much broader than paramere, bottle-shaped, widest at basal third, strongly narrowing ca. at midlength, apex broadly truncate; gonopore large, situated subapically (Fig. 16).

Form and Color. Body oval, weakly convex (Fig. 1), length 2.1 mm, width 1.35 mm. Head and elytra dark brown; pronotum brown; lateral margin of elytra paler than disc; labrum, maxillary palpomeres and antennomeres 1–6 reddish brown, antennal club paler; ventral surface brown, legs reddish brown.

Head. Clypeus with rather densely arranged fine punctures, interstices without microsculpture; lateral deflexed extensions not defined by ridge. Anterior margin of clypeus with narrow bead laterally. Frontoclypeal suture undetectable. Frons with sparser and coarser punctures than on clypeus, without microsculpture on interstices. Eyes small, clearly protruding, interocular distance ca. 7× as wide as one eye in dorsal view. Labrum exposed, sinuate on anterior margin. Mentum densely granulated, without punctures, ca. 2× as wide as long, not depressed anteromedially, anterior margin slightly protruding medially. Submentum below the level of mentum. Antenna with 9 antennomeres, scapus ca. 2.5× as long as antennomeres 2–5 combined, club compact, last club antennomere the widest. Maxillary palpomere 2 moderately swollen, palpomere 4 almost symmetrical, widest in middle, equal to palpomere 2 in length, longer than palpomere 3.

Thorax. Pronotum ca. 2.6× as wide as long; pronotal punctation similar to that on frons, interstices without microsculpture. Lateral margins with strong bead overlapping to anterior margin, posterior margin of pronotum without bead. Prosternum strongly tectiform, antennal grooves absent. Mesoventrite strongly and abruptly raised medially to form a narrow longitudinal lamina not contacting metaventral process posteriorly, cavities for reception of procoxae absent. Metaventrite weakly convex, with a small glabrous portion, with a posteromedial depression on elevated portion. Elytra widely explanate laterally, with 10 series of large punctures, series 1–5 almost reaching base, series 6–10 abbreviated anteriorly; interval punctures very fine but distinct, similar to on pronotum; interstices without microsculpture. Humeral bulge absent, lateral margin of elytron very finely serrate; epipleuron wide throughout.Profemur glabrous, anterior margin angulate near base, with a large basal depression with golden pubescence, tibial groove sharply defined. Mesofemur with sparse and strong punctures on anterior half, each puncture with a short seta; posterior half glabrous, with fine longitudinal sculpture. Metafemur with fine longitudinal sculpture and scattered fine punctures. Tibiae flat, meso- and metatibiae with long and stout spines along outer face and 1 or 2 pairs of spines on apical half of inner face; metatibial long spur longer than first tarsomere. First metatarsomere almost as long as metatarsomeres 2–3 combined.

Abdomen. Abdomen with five ventrites; first ventrite not longer than ventrites 2–5, without median longitudinal carina; fifth ventrite rounded, not emarginate apically.

Male genitalia. Phallobase much shorter than parameres, with a thin and long basal manubrium. Paramere without S-shaped strongly sclerotized portion, narrow throughout, weakly curved on outer margin, rounded apically. Median lobe much broader than paramere, bottle-shaped, widest in basal third, strongly narrowed ca. at midlength, apex broadly truncate; gonopore large, situated subapically (Fig. 16).

Omicrogiton roberti is similar to O. coomani Balfour-Browne, 1939 in the aedeagus without the strongly sclerotized S-shaped portion of the paramere. It differs from O. coomani by the morphology of the aedeagus (median lobe very wide with very large subapical gonopore and very short phallobase in O. roberti, rather narrow and with small apical gonopore and rather long phallobase in O. coomani) and by the pronotal interstices without fine mesh-like microsculpture (with fine mesh-like microsculpture in O. coomani).

The species is named after Dr. Robert Bagrie Angus, a British specialist on the Helophoridae, who helped us a lot with this study.

The holotype was collected in a decaying banana trunk together with specimens of O. hainanensis and O. coomani.

China (Hainan).

CHINA, Yunnan: 2 males, 6 unsexed spec. (SYSU, NMPC): Laiyanghe, Xinzhai Cun, 1487 m, 22.631°N, 101.132°E, 21.v.2011, Song Keqing lgt.; 1 male, 2 unsexed spec (SYSU): Mandian Nabanhe Conv., 11.i.2004, Li & Tang lgt.; 1 spec. (NMPC): Laiyanghe, Yutang village, in decaying banana trunk, 22.v.2011, Keqing Song lgt. VIETNAM: 1 male (IZCAS): Tonkin, Hoa-Binh, leg. A. de Cooman.

Body length 3.2–3.4 mm, width 2.2 mm. Dorsal surface dark brown, ventral surface brown to dark brown. Labrum weakly bisinuate on anterior margin, not distinctlx projecting anteriad. Scapus ca. 2.2× as long as antennomeres 2–5 combined, slightly shorter than antennal club. Head, pronotum and elytra with similar sparse and fine punctation, interstices without fine microsculpture; elytra with 10 series of punctures, series 6–7 abbreviated anteriorly. Prosternum strongly tectiform, sharp anteriorly. Mesoventral elevation much longer than wide, with distinct longitudinal groove medially, posteriorly fused with metaventral process, not projecting posteriad into a process overlapping metaventrite. Metaventrite with a longitudinal glabrous elevated band medially, forming together with mesoventral plate a joint meso-metaventral elevation. Phallobase ca. 0.3× as long as paramere; paramere rather wide throughout, outer margin slightly concave subapically, apex semicircular. Median lobe slightly narrower than paramere, lateral margin almost parallel, apex narrowly rounded, gonopore of moderate size, subapical (Fig. 20).

Mircogioton coomani differs from Mircogioton spinosus Bameul, 1993, M. seriatus Hebauer, 2006 and M. irregularis Hebauer, 2006 in mesoventrite fused with metaventral process (in contrast, mesoventrite is projecting into a long process overlapping metaventrite in the latter three species). It differs from M. grandis Bameul, 1993 and M. julieae (Malcolm, 1981) by the anterior margin of the labrum bisinuate (in contrast, labrum is simply concave on anterior margin in the latter two species). From M. julieae it also differs by apically broad paramere and apex of median lobe not distinctly narrowed. From M. grandis it may be also distinguished by smaller body size (up to 3.5 mm, in comparison with 3.8 mm in M. grandis).

This species was described by d’Orchymont (1937) based on a single female collected by A. de Cooman in “Tonkin, Hoa Binh”. The senior author examined one male collected by the same collector and bearing the same label data. Except of clearly being a part of the same material from which M. coomani was collected, the examined specimen agrees in all details with the original description. We therefore consider it represents M. coomani although we have not checked the female holotype.

Malcolm (1981) described Ischyromicrus cognitus Malcolm, 1981 based on a female from upper Mekong (later transferred to Mircogioton by Hansen (1991)). The species was redescribed by Bameul (1993). The characters described by Malcolm (1981) and Bameul (1993) are identical with the specimens of M. coomani in our hands. The type locality of M. cognitus is situated in northeastern Laos not far from the border with China rather than in Vietnam as supposed by Malcolm (1981) (Bameul 1993, Hansen 1999). Bameul (1981) moreover noticed that “in the description of M. cognitus, no characters really differ from those given by d’Orchymont (1937) in his description of M. coomani” and supposed that M. cognitus is synonym of M. coomani. We are following this opinion here and consider M. cognitus as a junior subjective synonym of M. coomani.

The recently collected specimens examined here were found in decaying banana trunk (K.-Q. Song and L. Tang, pers. comm.).

China (Yunnan), northern Laos. New genus and species for China.

Syntypes: 2 specimens on one card (BMNH): “Peratogonus reversus Type DS Nagasaki 14.4.81 // Japan G. Lewis Sharp coll. 1905 – 313”; 1 upside down spec. (BMNH): “Peratogonus reversus Sharp // Japan G. Lewis // 30.3.81”.

Figures 7–13. 

Morphology of Omicrogiton Orchymont, 1919 and Peratogonus Sharp, 1884 7 Dorsal habitus of O. insularis Orchymont, 1919 8–11 Habitus of P. reversus Sharp, 1884 (8 syntype from Japan, dorsal view 9 specimen from China, dorsal view 10 specimen from China, lateral view 11 syntype from Japan, ventral view) 12–13 Comparison of metaventral punctation of Peratogonus (12 P. reversus 13 P. grandis Bameul, 1994).

JAPAN: 1 male (BMNH): “Japan, Kobe. Mayasan 14.vi.29 JEA Lewis. Nr 1530”; 1 male (NMPC): Kanagawa Pref., Manazuru Peninsula, 4.xi.2006, P. Jaloszynski lgt.; 1 spec. (NMPC): Chiba Pref., Kôzaki shrine, Kôzaki-machi, 15.x.2001, P. Jaloszynski lgt. CHINA: Guangdong: 1 male (SYSU): Conghua, Liuxihe forest park, 16.v.2012, Tong Xiaoli leg. (in Chinese); 1 male (SYSU): Fengkai, Heishiding Natural Reserve, 23°27.9'N 111°54.3'E, 190–260 m, Fenglong Jia leg.; 1 male (NMPC): W of Qixing, Heishiding nature reserve, sifting of moist leaf litter in the dried-up streambeds and along the streams in the primary lowland forest, 190–260 m a.s.l., 23°27.9'N, 111°54.3'E, 1.–3.v.2011, Fikáček & Hájek lgt. Jiangxi: 1 male (NMPC): Jinggangshan Mts., Xiangzhou (forested valley S of the village), cut and decaying tops of bamboo trunks at side of a trail in the secondary forest and among the fields, 26°35.5'N, 114°16.0'E, 374 m, 26.iv.2011, Fikáček & Hájek lgt. Taiwan: 1 male, 9 spec. (NMPC, SYSU): Maoli County, Nanjhuang Twnsh., S-Nanjhuang Rd. 124, km 3 + forest road, forest compost, 26.x.2010, S. Vít lgt.

Body length 2.1 mm, width 1.5 mm, strongly convex. Head and pronotum with fine microsculpture between punctures. Elytra with 10 striae, striae 1–5 reaching elytral base, striae 6–10 abbreviated anteriorly, not reaching base; elytral intervals with distinct fine punctures, without microsculpture between punctures. Prosternum steeply raised in middle to form a triangular medially carinate tablet. Mesoventrite flat medially, widely fused with metaventrite. Metaventrite laterally with much coarser and stronger punctures than on its median portion. Aedeagus (Figs 21–22) with phallobase ca. as long as paramere, tube-like; paramere broad basally, gradually narrowing towards apex; median lobe slender, parallel-sided, with very long basal struts, gonopore indistrinct, apex slightly emarginate.

Figures 14–22. 

Ventral morphology (14) and morphology of aedeagus (15–22). 14 detail of meso- and metaventrite of Mircogioton coomani Orchymont, 1937 15 Omicrogiton hainanensis sp. n., holotype 16 O. roberti sp. n., holotype 17–18 O. coomani Balfour-Browne, 1939 (17 lectotype; 18 non-type specimen from China) 19 O. insularis Orchymont, 1919, specimen from Sarawak 20 Mircogioton coomani Orchymont, 1937, Chinese specimen 21–22 Peratogonus reversus Sharp, 1884 (21 syntype 22 specimen from China).

This species can be easily distinguished from P. grandis Malcolm, 1981 occurring in India (Sikkim) by punctures on the lateral portion of the metaventrite much deeper and larger than medially. From P. corporaali Orchymont, 1926 occurring in Indonesia (Java), it may be distinguished by pronotum with distinct microsculpture between punctures, elytra with striae 6–10 not reaching elytral base (stria 8 almost reaching base, striae 9–10 reaching base in P. corporaali), elytral intervals with distinct punctures, flat mesoventral plate, and metaventrite with coaser and sparser punctures medially.

This species was firstly described from Nagasaki, Kyushu in southern Japan by Sharp (1884). It was subsequently reported from Taiwan by Knisch (1921). The comparison of the specimens from Taiwan and southern continental China revealed that they are identical with those from Japan.

When Malcolm (1981) described Peratogonus grandis Malcolm, 1981, he diagnosed it from P. reversus by the different body size (2.21×1.64 mm in P. grandis versus 1.72×1.31 in P. reversus) and by the shallower and smaller punctures on lateral portion of the metaventrite. The material examined by us revealed that the specimen of P. reversus examined by Malcolm (1981) was smaller than its individuals usually are (i.e. body length 1.9–2.2 mm). Therefore, the body size can not be used as a reliable character to distinguish the two species, in contrast to the punctation of the metaventrite, which seems to be a reliable character to distinguish the two species.

Most specimens examined here were found by sifting forest leaf litter.

China (Guangdong, Jiangxi, Taiwan), Japan (Honshu, Kyushu). New genus and species for mailand China.

Figures 23–24. 

Examples of habitats of Chinese Omicrogiton Orchymont, 1919.