Two new species of the genus Nephrotoma (Diptera, Tipuloidea, Tipulidae) from China with a key to species from Mainland China.

Nephrotoma liankangensis sp. n. and Nephrotoma pseudoliankangensis sp. n. are described from males and females collected from Henan and Yunnan provinces, China. Morphological descriptions and illustrations for the new species are provided. A key to known species from mainland China is provided. Some internal reproductive structures, including male semen pump, female vaginal apodeme and spermatheca, are described and compared. The possible usefulness of these internal reproductive structures for separating related species is analyzed. The type specimens are deposited in the animal specimen room, School of Life Sciences, Anqing Normal University, Anhui Province, China.

Introduction

is a large genus in the family . It was originally erected by Meigen (1803) with type species (Fabricius, 1781), which is widely distributed in Palaearctic region. This genus is characterized by the following characters: median size; Rs short, cell m1 with or without petiole; ninth tergite covered with small black spines, never completely confused with ninth sternite, has a varied shaped posterior extension; outer gonostylus more or less lobe-shaped, generally flattened, fleshy or partly sclerotized; female cerci longer than hypovalva (Tangelder 1983, 1984). Up to now, 446 species and 29 subspecies of have been reported worldwide, with 78 species recorded from mainland China (Oosterbroek 2015).

During this study of crane fly specimens collected from Henan and Yunnan provinces, China, two new species of were found. Morphological descriptions and detailed illustrations for the new species are provided herein. A key to known species from mainland China is provided. In addition, some internal reproductive structures of the new taxa, including male semen pump, female vaginal apodeme and spermatheca, are described and compared. The possible usefulness of these internal reproductive structures for separating related species is analyzed.

Material and methods

The specimens examined in this study were collected from Henan and Yunnan provinces by the first author and undergraduates of the School of Life Sciences, Anqing Normal University. The genitalia, including male hypopygium and female ovipositor were removed and soaked in 10% NaOH for 12 hours to clear the muscle for examination. The cleared genitalia were immersed in glycerin jelly, and then examined and drawn using Leica MZ125 (Leica, Germany) stereomicroscope. All measurements were made with the aid of a digital caliper in millimeters (mm). The terminology and methods of description and illustration follow that of Alexander and Byers (1981) and Frommer (1963).

The key was principally constructed from descriptions in the literature without examination of the type species of most of these species, and should be considered preliminary. The characters used in the key rely primarily on the structure of genitalia, the variation of veins and the number of stripes on the prescutum.

Taxonomy

sp. n.

http://zoobank.org/50E64607-C1E1-4AD1-88AB-10F98DF3FF37

Figs 1–9 , 10–19

Figures 1–9.

sp. n. 1 head, dorsal view 2 thorax, dorsal view 3 left wing 4 hypopygium, lateral view 5 hypopygium, ventral view 6 ninth tergite, dorsal view 7 outer gonostylus, lateral view 8 inner gonostylus, lateral internal view 9 inner gonostylus, lateral external view. Abbreviations: i gonst, o gonst, S.

= inner gonostylus

= outer gonostylus

= stergite

Figures 10–19.

sp. n. 10 aedeagal guide, lateral view 11 aedeagal guide, dorsal view 12 semen pump, dorsal view 13 semen pump, lateral view 14 compressor apodeme 15 ovipositor, lateral view 16 ovipositor, dorsal view 17 ninth stergite and vaginal apodeme, dorsal view 18 spermatheca, dorsal view 19 spermatheca, lateral view. Abbreviations: aed gd, pm, ventr app, PIA, AIA, CA, me rdg, T, cerc, hyva.

= aedeagal guide

= paramere

= ventral appendage of aedeagal guide

= posterior immovable apodeme

= anterior immovable apodeme

= compressor apodeme

= median ridge

= tergite

= cercus

= hypovalva

Diagnosis.

Antennae with flagellum light brown, pleura light yellow conspicuously patterned with white, abdominal tergites with two black lateral stripes and one brown median stripe, ninth tergite with two rounded lobes which are densely covered with black spines, posterior margin of ninth tergite not concaved at base of lobes.

Description.

Male (n=2): body length 9.8 mm, wing 10.5 mm, antenna 5.8 mm.

Nasus yellow with black setae, palpi black. Antennae relatively long, if bent backward extending to the first abdominal tergite, scape and pedicel yellow, flagellum 10-segmented, with the first flagellomere yellow, with the second to tenth flagellomeres light brown and enlarged at both ends, the basal enlargement black with black setae basally, subequal to the flagellomeres from which they arise. Head yellow, occipital brand brown and narrow, along the middle line of occiput (Fig. 1).

Pronotum light brown, changing into yellow in middle. Prescutum yellow with three brown stripes, median one expanded apically, not extending to the hind border, lateral stripe straight and rounded apically, extending slight beyond the middle of median stripe (Fig. 2). The median stripe lighter in coloration than lateral one, sometimes divided by a yellow line (Fig. 2). Scutum light brown, each lobe with jet-black anterior border, median area of scutum yellow (Fig. 2). Scutellum yellowish. Postnotum light brown. Pleura yellowish brown, variegated by white on anepimeron, katepimeron, meron and basal laterotergite. Halters yellowish brown throughout. Legs with coxae and trochanters yellow; femora and tibiae yellow with brown tips; tarsi dark brown. Wings transparent, cells c and sc suffused with brown; stigma oval, dark brown; wing tip narrowed and slightly suffused with light brown. Cell r1 without stigmal trichia, cell m1 petiolate (Fig. 3).

Abdomen generally yellow, the first tergite light brown, tergites two to six with a light brown median stripe and two black lateral stripes, sternites two to seven with light brown median stripe, hypopygium chiefly yellowish brown. Male hypopygium (Figs 4, 5) with the ninth tergite having the median notch rounded basally, gradually narrowed to apex, separating the ninth tergite into two rounded lobes, the lobe black and densely covered with black spines (Fig. 6). Outer gonostylus lanceolate, basally widened and gradually narrowed to the end (Figs 4, 5, 7). Inner gonostylus with two black beaks (Figs 8, 9).

Aedeagal guide horn-shaped in lateral view, very acute apically (Fig. 10); paramere lamellate, blunt apically (Fig. 10); ventral appendage of aedeagal guide horn-like in lateral view, boot-shaped in dorsal view (Figs 10, 11).

Semen pump with narrow, dorsally bent in lateral view (Fig. 13); fan-shaped, with an obviously expanded median ridge in lateral view, in a 90° angle with posterior immovable apodeme (Figs 12–14); broader than compressor apodeme, with lateral margins arched and inner margins straight, separated medially (Fig. 12).

Female (n=2): body length 16.2 mm, wing 12.0 mm, antenna 3.2 mm.

The general coloration of head, thorax and abdomen similar to that of male.

Antennae relatively short, if bent backward not extending to abdomen, scape and pedicel yellow, flagellum 10-segmented, each flagellomere cylindrical, gradually shorter and slightly enlarged at base, the basal two flagellomeres yellow, three to ten flagellomeres yellowish brown with black at base.

Ovipositor yellowish brown, ninth sternite very thin, lanceolate, separated medially (Fig. 17). Sternite ten slightly shorter than cerci, parallel in lateral margins in dorsal PageBreakview (Fig. 16). Cerci long, acinacifoliate, widened at basal three fifths, narrowed at apical two fifths, surpassing the end of hypovalva (Fig. 15). Hypovalva simple, extending to nearly three quarters length of cerci (Fig. 15).

Vaginal apodeme widened at basal half and gradually tapered to the end, very acute apically (Fig. 17). Spermatheca spherical, brown, well-sclerotized, with membranous angular extension on lateral side (Figs 18, 19).

Material examined.

Holotype male. Pinned specimen. China: Henan Province, Xin County, Liankangshan National Nature Reserve, 18 Jul. 2014, coll. Qiulei Men. Paratype. Pinned specimen. China: 1 male 2 females, same data as holotype, coll. Wu Zeng.

Distribution.

China (Henan).

Etymology.

The specific epithet is a noun ‘liankang’ with Latin suffix ‘ensis’, referring to the distribution of the new species.

Remarks.

This new species is similar to , as discussed below, and another Chinese species, (Edwards, 1916), by the coloration of the prescutum and wings, the shape of lobes on the ninth tergite and the shape of inner gonostylus. It can be easily distinguished from the latter by the prescutum not bearing a black spot on anterior portion of the lateral stripe (this black spot present in as described by Liu et al. 2009: 43), the ninth tergite without spiny prominence on each side of lobes (this spiny prominence on each side of lobes in as illustrated by Sidorenko 1999: 112), and the inner gonostylus broad apically (apical half obviously narrower than that of in as illustrated by Sidorenko 1999: 112).

http://zoobank.org/5AAE0CD7-E0D8-454E-9EC0-173267C91215

Figs 20–27 , 28–36

Figures 20–27.

sp. n. 20 head, dorsal view 21 thorax, dorsal view 22 left wing 23 hypopygium, lateral view 24 hypopygium, ventral view 25 ninth tergite, dorsal view 26 outer gonostylus, lateral view 27 inner gonostylus, lateral view.

Figures 28–36.

sp. n. 28 aedeagal guide, lateral view 29 semen pump, dorsal view 30 semen pump, lateral view 31 compressor apodeme 32 ovipositor, lateral view 33 ovipositor, dorsal view 34 ninth stergite and vaginal apodeme, dorsal view 35 spermatheca, dorsal view 36 spermatheca, lateral view.

General coloration light yellow, antennae with flagellum black except the first flagellomere, pleura white conspicuously patterned with yellow, abdominal tergites with two black lateral stripes and one brown median stripe, ninth tergite with two rounded lobes, posterior margin of ninth tergite slightly concaved at base of lobes.

Male (n=2): body length 9.6 mm, wing 11.0 mm, antenna 5.1 mm.

Nasus brown with brown setae, palpi black. Antennae relatively long, if bent backward extending to the first abdominal tergite, scape and pedicel yellow, flagellum 10-segmented, with the first flagellomere yellow, with second to tenth flagellomeres black and enlarged at base and apex, each flagellomere with black setae at base, subequal to the flagellomeres where they are found. Head yellow without occipital brand (Fig. 20).

Pronotum entirely yellow. Prescutum yellow with three brown stripes, median one percurrent and expanded apically, lateral stripe straight and rounded apically, the area between lateral stripe and lateral border of prescutum suffused with brown (Fig. 21). Scutum light brown, each lobe with jet-black anterior border, median area of scutum yellow (Fig. 21). Scutellum yellowish brown. Postnotum light brown with white median PageBreakstripe. Pleura white, variegated by yellow on anepisternum and katepisternum. Halters yellowish brown throughout. Legs with coxae and trochanters yellow; femora and tibiae yellow with brown tips; tarsi dark brown. Wings transparent, cells c and sc variegated with brown; stigma oval, dark brown; wing tip narrowed and slightly suffused with light brown. Cell r1 with five to six stigmal trichiae, cell m1 petiolate (Fig. 22).

Abdomen generally yellow, the first segment yellow with light brown tergite, tergites two to seven with a brown median stripe and two black lateral stripes, the median stripe expanded at hind border, tergite eight entirely brownish black; sternites two to seven with light brown median stripe, hypopygium chiefly yellowish brown. Male hypopygium (Figs 23, 24) with the ninth tergite having the median notch rounded and widened basally, separating the ninth tergite into two rounded black lobes, which densely covered with black spines, almost connected to each other (Fig. 25). Outer gonostylus lanceolate, basally widened and gradually narrowed to the end (Figs 23, 24, 26). Inner gonostylus with two black beaks, the dorsal side of inner gonostylus obviously extended (Fig. 27).

Aedeagal guide very similar to that of , with paramere not blunt apically, the dorsal margin slightly arched, the ventral and outer margins forming an obtuse angle (Fig. 28).

Semen pump very similar to that of , with not bent directed dorsad at the apex in lateral view (Fig. 30); fan-shaped, broader than that of (Figs 29, 31), with median ridge slightly expanded in lateral view, which more degenerated than that of (Fig. 30); more expanded than that of in lateral view (Fig. 30).

Female (n=3): body length 15.8 mm, wing 13.0 mm, antenna 2.5 mm.

The colouration of head, thorax and abdomen similar to those of male.

Antennae relatively short, scape and pedicel yellow, flagellum 10-segmented, each flagellomere cylindrical, gradually shorter, the basal two flagellomeres entirely yellow, three to ten flagellomeres yellowish brown with black at base.

Ovipositor (Figs 32, 33) very similar to that of , with ninth sternite obviously longer than that of (Fig. 34).

Vaginal apodeme widened at basal two fifths, the rest of vaginal apodeme tubular, parallel, acute apically (Fig. 34).

Spermatheca spherical, brown, well-sclerotized, with membranous extension truncate (Figs 35, 36).

Holotype male. Pinned specimen. China: Yunnan Province, Kunming, Baofeng wetland park, 31 Aug. 2013, coll. Bin Zhang. Paratype. Pinned specimen. China: 1 male 3 females, same data as holotype.

China (Yunnan).

The specific epithet is based on the name of the related species, , with the Latin prefix ‘pseudo’, referring to the morphological similarity of the new species to .

This new species is externally similar to by the colouration of head, thorax, abdomen and wings, and the shape of inner and outer gonostyli. It can be easily distinguished from the latter by antennae with the second to tenth flagellomeres black (the second to tenth flagellomeres yellow with basal enlargement black in ), the occiput unpatterned (with brown median brand in as shown in Fig. 20), and the inner gonostylus with the dorsal margin obviously extended (just slightly extended in as shown in Figs 8, 9). The new species is also similar to in some internal reproductive organs, but differs from the latter in the female vaginal apodeme widened at basal two fifths, tubular and parallel at apical three fifths (vaginal apodeme widened at basal half and gradually tapered to the end in as shown in Fig. 17), the spermatheca laterally with membranous extension truncate (with membranous extension angular in as shown in Fig. 18), the male aedeagal guide with paramere not blunt apically (apically blunt in as shown in Fig. 10), the semen pump with posterior immovable apodeme not dorsally bent (dorsally bent in as shown in Fig. 13), and compressor apodeme with median ridge slightly expanded in lateral view (median ridge obviously more expanded than that of in as shown in Fig. 13).

Discussion

Based on morphological comparison, the characters of the vaginal apodeme, spermatheca and semen pump are uniform in different individuals of and . However, these structures show noticeable differences between the two species. More comparative morphological study may not only prove a high application value of the characters of these internal reproductive structures in separating relative species, but also prove the roles of these structures for phylogenetic studies as mentioned by Tangelder (1985). Moreover, although used less frequently, the characteristics of female genitalia, especially the vaginal apodeme and ninth sternite, may be helpful to effectively distinguish species in which males are difficult to collect.

1	Prescutum with stripe(s)	2
–	Prescutum without stripe	3
2 (1)	Prescutum with only one broad stripe, which almost covers the whole prescutum (see Savchenko 1973: p. 164)	Nephrotoma villosa (Savchenko, 1973) (China: Anhui)
–	Prescutum with more than one stripe	5
3 (1)	Stigma covered with macrotrichia	4
–	Stigma not covered with macrotrichia (see Yang and Yang 1990: p. 477)	Nephrotoma hypogyna Yang & Yang, 1990 (China: Yunnan)
4 (3)	Head and thorax brown with grayish-white pruinosity; wing entirely light brown (see Yang and Yang 1993: p. 54)	Nephrotoma guangxiensis Yang & Yang, 1993 (China: Guangxi)
–	Head yellow, thorax brown, without grayish-white pruinosity; wing hyaline, tinged with light brown at apex (see Yang and Yang 1993: p. 56)	Nephrotoma jinxiuensis Yang & Yang, 1993 (China: Guangxi)
5 (2)	Prescutum with black stripes	6
–	Prescutum with stripes not black	7
6 (5)	Prescutal stripes with velvety black margin	29
–	Prescutal stripes without velvety black margin	28
7 (5)	Prescutum with four stripes	8
–	Prescutum with three stripes	9
8 (7)	Male tergite nine without median notch, medially terminated into an obtuse lobe (see Yang and Yang 1987b: p. 134, fig. 4B); each flagellomere bicoloured (see Alexander 1925: p. 407)	Nephrotoma rectispina Alexander, 1925 (China: Hubei, Guizhou)
–	Male tergite nine with U-shaped notch; flagellum black throughout	10
9 (7)	Abdomen without dark apical or lateral stripes	11
–	Abdomen with dark apical and/or lateral stripes	12
10 (8)	Male tergite nine produced into two lobes; pleura yellow variegated with pale yellow (see Alexander 1949: p. 517)	Nephrotoma quadrinacrea Alexander, 1949 (China: Hubei, Guangdong)
–	Male tergite nine produced into four lobes; pleura entirely light yellow (see Alexander 1949: p. 515)	Nephrotoma progne Alexander, 1949 (China: Guangdong)
11 (9)	Male tergite nine projected into four lobes	13
–	Male tergite nine projected into two lobes	14
12 (9)	Occiput with mark	17
–	Occiput without mark	18
13 (11)	Caudal margin of male sternite eight with an appendage directed caudally (see Yang and Yang 1997: p. 30, Pl. III, fig. 1); abdomen dark brown with two to four segments yellow (see Yang and Yang 1997: p. 30)	Nephrotoma meridionalis Yang & Yang, 1997 (China: Hainan, Guangxi)
–	Caudal margin of male sternite eight without appendage; abdomen uniformly coloured	15
14 (11)	Cell m1 petiolate (see Alexander 1951: p. 1097); male sternite eight without produced appendage at caudal margin (see Alexander 1967: Pl. IV, fig. 30)	Nephrotoma inorata Alexander, 1951 (China: Xizang; India)
–	Cell m1 sessile; male sternite eight with produced appendage at caudal margin	16
15 (13)	Occiput without mark (see Yang and Yang 1990: p. 122); male sternite nine without appendage at caudal margin (see Yang and Yang 1990: p. 124, fig. 1A)	Nephrotoma sichuanensis Yang & Yang, 1990 (China: Sichuan)
–	Occiput with a linear mark medially; male sternite nine with an appendage bifid and directed caudally (see Tangelder 1984: p. 51, fig. 125; p. 58, fig. 149)	Nephrotoma koreana Tangelder, 1984 (China: Hebei, Heilongjiang, Ningxia; Russia; North Korea)
16 (14)	Flagellum dark yellow; scutum with spots brown; abdomen dark yellow (see Yang and Yang 1987: p. 243)	Nephrotoma qinghaiensis qinghaiensis Yang & Yang, 1987 (China: Qinghai)
–	Flagellum with first flagellomere yellowish brown, the remainder of flagellum brown; scutum with black spots; abdomen blackish brown (see Yang and Yang 1990: p. 480)	Nephrotoma qinhaiensis nigrabdomen Yang & Yang, 1990 (China: Heilongjiang, Inner Mongolia)
17 (12)	Cell m1 sessile	24
–	Cell m1 petiolate	25
18 (12)	Flagellomeres bicoloured, dark brown on enlarged bases, brown on apical portions of each flagellomere (see Alexander 1914: p. 158)	Nephrotoma flavonota (Alexander, 1914) (China: Zhejiang, Fujian, Hainan; Japan)
–	Flagellomeres uniformly coloured	19
19 (18)	Flagellum with first flagellomere yellow, the remainder of flagellum black or brown	20
–	Flagellum entirely black	21
20 (19)	Inner gonostylus with toothed crest (see Tangelder 1984: p. 85, fig. 277; Yang and Yang 1991: p. 44, fig. 2C)	22
–	Inner gonostylus without crest (see Yang and Yang 1990: p. 477, Pl. II, fig. 3)	23
21 (19)	Wing weak brown; prescutum with orange stripes (see Alexander 1949: p. 513)	Nephrotoma citricolor Alexander, 1949 (China: Fujian)
–	Wing whitish hyaline; prescutum with fuscous stripes (see Matsumura 1916: p. 466)	Nephrotoma makiella (Matsumura, 1916) (China: Fujian, Taiwan)
22 (20)	Male sternite eight without produced appendage at caudal margin (see Tangelder 1984: p. 85, fig. 272); wing yellowish with dark brown stigma (see Alexander 1935: p. 228)	Nephrotoma profunda Alexander, 1935 (China: Sichuan, Hubei)
–	Male sternite eight with produced appendage at caudal margin (see Yang and Yang 1991: p. 44, fig. 2A); wing hyaline with light brown stigma	Nephrotoma hunanensis Yang & Yang, 1991 (China: Hunan)
23 (20)	Male tergite nine with two horn-shaped processes (see Yang and Yang 1990: p. 477, Pl. II, fig. 2); flagellum with flagellomeres brown except the first yellow	Nephrotoma ruiliensis Yang & Yang, 1990 (China: Yunnan)
–	Male tergite nine without horn-shaped processes (Fig. 25); flagellum with flagellomeres black except the first yellow	Nephrotoma pseudoliankangensis sp. n. (China: Yunnan)
24 (17)	Vertex with a triangular stripe; inner gonostylus with a spinous lobe at posterior basal portion (see Alexander 1937: p. 22, fig. 26)	Nephrotoma stylacantha Alexander, 1937 (China: Fujian, Jiangsu)
–	Vertex with a thin linear stripe; inner gonostylus without lobe described as above (see Alexander 1941b: Pl. III, fig. 34)	Nephrotoma alticrista Alexander, 1941 (China: Sichuan)
25 (17)	Male tergite nine without notch at caudal margin, medially terminated into an obtuse lobe (see Alexander 1940: Pl. VIII, fig. 7)	Nephrotoma medioproducta Alexander, 1940 (China: Zhejiang)
–	Male tergite nine with notch in the middle of caudal margin	26
26 (25)	Male tergite nine with two spinous processes excluding setae (see Sidorenko 1999: p. 112, Pl. 64, fig. 3)	Nephrotoma sinensis (Edwards, 1916) (China: Beijing, Henan, Jiangsu, Shaanxi, Sichuan, Jiangsu, Yunnan, Hainan, Taiwan; Russia; North Korea; South Korea)
–	Male tergite nine without spinous process excluding setae (see Alexander 1935a: Pl. IV, fig. 50)	27
27 (26)	Pleura yellow with a variable amount of red; male tergite nine with a V-shaped notch in the middle of caudal margin (see Alexander 1935a: Pl. IV, fig. 50)	Nephrotoma omeiana Alexander, 1935 (China: Sichuan, Hubei, Taiwan)
–	Pleura yellowish brown with a variable amount of white; male tergite nine with a rounded notch in the middle of caudal margin (Fig. 6)	Nephrotoma liankangensis sp. n. (China: Henan)
28 (6)	Scutum uniformly coloured	30
–	Scutum with dark stripe or spot, or with different colours in middle portion	31
29 (6)	Cell m1 petiolate (see Alexander 1935a: Pl. I, fig. 20; Alexander 1949: p. 519)	66
–	Cell m1 sessile (see Alexander 1935c: Pl. I, fig. 15)	Nephrotoma catenata catenata Alexander, 1935 (China: Sichuan)
30 (28)	Abdomen not uniformly coloured, with dark stripe on tergites	32
–	Abdomen uniformly coloured (see Yang and Yang 1991: p. 39)	Nephrotoma basiflava Yang & Yang, 1991 (China: Qinghai)
31 (28)	Occiput without a mark	34
–	Occiput with a mark	35
32 (30)	Cell m1 sessile (see Alexander 1936a: p. 15)	Nephrotoma drakanae Alexander, 1936 (China: Gansu, Inner Mongolia)
–	Cell m1 petiolate	33
33 (32)	Occiput without a mark; scutellum orange ochreous (see Edwards 1916: p. 266)	Nephrotoma parva (Edwards, 1916) (China: Jiangxi, Guangxi, Guangdong, Taiwan)
–	Occiput with triangular black spot; scutellum black (see Edwards 1928: p. 700)	Nephrotoma distans Edwards, 1928 (China: Xizang)
34 (31)	Antennae black throughout; abdomen chiefly black, with fourth, fifth and base of third tergites orange (see Alexander 1941a: p. 405)	Nephrotoma aurantiocincta Alexander, 1941 (China: Sichuan, Yunnan)
–	Antennae variously coloured but not black throughout; abdomen chiefly yellow, with fourth and fifth tergites not orange	36
35 (31)	Flagellum with basal three segments yellow (see Yang and Yang 1988: p. 111)	Nephrotoma catenata guizhouensis Yang & Yang, 1988 (China: Guizhou)
–	Flagellum with basal segments not yellow, or only first segment yellow	42
36 (34)	Abdomen with seventh segment black	37
–	Abdomen with seventh segment not black	38
37 (36)	Cell m1 long-petiolate, longer than m-m (see Alexander 1936b: Pl. I, fig. 2)	Nephrotoma hainanica Alexander, 1936 (China: Hainan)
–	Cell m1 short-petiolate, shorter than m-m (see Alexander 1935b: Pl. I, fig. 4)	Nephrotoma biarmigera Alexander, 1935 (China: Zhejiang)
38 (36)	Male sternite eight without produced appendage in the middle of caudal margin (see Yang and Yang 1993: p. 55, fig. 2A; Yang and Yang 1991: p. 44, fig. 1A; Yang and Yang 1990: p. 124, fig, 4A)	39
–	Male sternite eight with produced appendage in the middle of caudal margin (see Yang and Yang 1995: p. 420, fig. 1; Yang and Yang 1987b: p. 132, fig. 2A)	40
39 (38)	Process of male tergite nine widened basally and narrowed apically (see Yang and Yang 1993: p. 55, fig. 2B)	Nephrotoma tianlinensis Yang & Yang, 1993 (China: Guangxi)
–	Process of male tergite nine horn-shaped (see Yang and Yang 1991: p. 44, fig. 1B; Yang and Yang 1990: p. 124, fig. 4B)	41
40 (38)	Male sternite nine with an appendage directed ventrally in the middle of caudal margin (see Yang and Yang 1995: p. 420, fig. 1)	Nephrotoma zhejiangensis Yang & Yang, 1995 (China: Zhejiang)
–	Male sternite nine without appendage (see Yang and Yang 1987a: p. 132, fig. 2A)	Nephrotoma geniculata Yang & Yang, 1987 (China: Inner Mongolia, Hubei, Sichuan, Guizhou)
41 (39)	Abdominal tergites with median stripe; inner gonostylus without crest (see Yang and Yang 1991: p. 44, fig. 1C)	Nephrotoma cuneata Yang & Yang, 1991 (China: Hubei, Hunan)
–	Abdominal tergites without median stripe; inner gonostylus with crest (Yang and Yang 1990: p. 124, fig. 4C)	Nephrotoma xichangensis Yang & Yang, 1990 (China: Sichuan)
42 (35)	The first flagellomere not the same colour as remaining flagellomeres of flagellum	43
–	Flagellum with flagellomeres all the same colour	44
43 (42)	Inner gonostylus with crest	45
–	nner gonostylus without crest	46
44 (42)	Male tergite nine without emargination, or with shallow emargination on caudal margin	53
–	Male tergite nine with U-shaped or V-shaped notch on caudal margin	54
45 (43)	Crest of inner gonostylus with tooth on dorsal margin	47
–	Crest of inner gonostylus without tooth (see Oosterbroek 1985: p. 268, fig. 103)	Nephrotoma hirsuticauda Alexander, 1924 (China: Heilongjiang, Inner Mongolia, Gansu, Ningxia; Russia; Japan; Mongolia; North Korea)
46 (43)	Caudal margin of male tergite nine produced into a pair of flattened black lobes, their medial edges coarsely toothed; outer gonostylus with tip curved and subacute, the margin of gonostylus with three or four teeth (see Alexander 1935b: Pl. II, fig. 31)	Nephrotoma nigrostylata Alexander, 1935 (China: Hubei, Zhejiang, Fujian, Sichuan, Guizhou, Guangxi)
–	Caudal margin of male tergite nine, and outer gonostylus not as above	48
47 (45)	Outer gonostylus abruptly narrowed at apical half; inner gonostylus with a relatively short beak (see Oosterbroek 1985: p. 250, figs. 36, 37)	Nephrotoma relicta (Savchenko, 1973) (China: Heilongjiang, Sichuan, Hubei; Russia; North Korea; South Korea; Mongolia; Finland)
–	Outer gonostylus gradually narrowed; inner gonostylus with a relatively long beak (see Oosterbroek 1985: p. 250, figs 34, 35)	Nephrotoma parvirostra Alexander, 1924 (China: Beijing, Hebei, Heilongjiang, Hubei, Sichuan; Russia; Mongolia; South Korea; Japan)
48 (46)	Abdominal tergites without median stripe (see Alexander 1935b: p. 200)	Nephrotoma evittata Alexander, 1935 (China: Sichuan, Yunnan)
–	Abdominal tergites with median stripe	49
49 (48)	Male sternite eight with appendage in the middle of caudal margin (see Yang and Yang 1990: p. 478, Pl. III, fig. 1; Yang and Yang 1987b: p. 131, Pl. I, fig. 1A)	50
–	Male sternite eight without appendage in the middle of caudal margin (see Yang and Yang 1987a: p. 130, fig. 1B; Oosterbroek 1985: p. 271, fig. 111; Alexander 1935a: p. 135)	51
50 (49)	Male tergite nine with lobes acute apically (see Yang and Yang 1990: p. 478, Pl. III, fig. 2)	Nephrotoma concava Yang & Yang, 1990 (China: Gansu)
–	Male tergite nine with lobes rounded apically (see Yang and Yang 1987b: p. 131, Pl. I, fig. 1B)	Nephrotoma hubeiensis Yang & Yang, 1987 (China: Hubei)
51 (49)	Male tergite nine with two blunt processes on each side of hind margin (see Yang and Yang 1987a: p. 130, fig. 1C)	Nephrotoma xizangensis Yang & Yang, 1987 (China: Xizang)
–	Male tergite nine with two acute processes on each side of hind margin	52
52 (51)	Occipital mark brown, rounded; abdomen with segments seven to nine dark brown (see Alexander 1914: p. 162); male tergite nine with two spinous processes at caudal margin (see Oosterbroek 1985: p. 271, fig. 112)	Nephrotoma repanda (Alexander, 1914) (China: Sichuan; Russia; North Korea; South Korea; Japan)
–	Occipital mark black, subtriangular; abdomen with all segments yellow (see Alexander 1935a: p. 134); male tergite nine with two horn-shaped processes at caudal margin (see Alexander 1935a: Pl. IV, fig. 43)	Nephrotoma retenta Alexander, 1935 (China: Sichuan-Xizang border)
53 (44)	Male tergite nine with process not directed caudally (see Tangelder 1984: p. 40, fig. 81)	Nephrotoma libra Alexander, 1951 (China: Xizang)
–	Male tergite nine with process directed caudally (see Yang and Yang 1987a: p. 131, fig. 2B; p. 132, fig. 3B)	55
54 (44)	Tergite nine dividing into four processes	56
–	Tergite nine dividing into two processes	57
55 (53)	Vertex with a light brown spot between eyes; male sternite nine with an appendage directed caudally in the middle of hind margin (see Yang and Yang 1987a: p. 132, fig. 3A)	Nephrotoma didyma Yang & Yang, 1987 (China: Xizang)
–	Vertex with a black spot between eyes; male sternite nine without appendage in the middle of hind margin (see Yang and Yang 1987a: p. 131, fig. 2A)	Nephrotoma claviformis Yang & Yang, 1987 (China: Xizang)
56 (54)	Inner gonostylus with crest	58
–	Inner gonostylus without crest	59
57 (54)	Male sternite eight with appendage in the middle of caudal margin	67
–	Male sternite eight without appendage in the middle of caudal margin	68
58 (56)	Inner gonostylus produced caudad into a long tail-like portion (see Alexander 1935a: Pl. IV, fig. 44, as attenuata); sternite eight without appendage in the middle of caudal margin (see Alexander 1935a: p. 136 as attenuata)	Nephrotoma nigrohalterata Edwards, 1928 (China: Sichuan, Xizang)
–	Inner gonostylus without such tail-like portion; sternite eight with an appendage in the middle of caudal margin	60
59 (56)	Male sternite eight with appendage in the middle of caudal margin (see Oosterbroek 1985: p. 244, fig. 10)	Nephrotoma aculeata (Loew, 1871) (China: Heilongjiang, Shanxi; widely distributed in Palaearctic Region)
–	Male sternite eight without appendage in the middle of caudal margin	62
60 (58)	Occipital mark dark brown; male sternite nine with appendage in the middle of caudal margin (see Oosterbroek 1985: p. 272, fig. 115)	Nephrotoma virgata (Coquillett, 1898) (China: Anhui, Hebei, Hubei, Sichuan, Zhejiang; Russia; North Korea; South Korea; Japan)
–	Occipital mark black; male sternite nine without appendage in the middle of caudal margin	61
61 (60)	Flagellum entirely brown; male sternite eight with a curved appendage directed ventrally at caudal margin (see Yang and Yang 1990: p. 124, fig. 3A)	Nephrotoma ocellata Yang & Yang, 1990 (China: Sichuan)
–	Flagellum entirely black; male sternite eight with a straight appendage directed caudad at caudal margin (see Oosterbroek 1984: p. 122, fig. 2)	Nephrotoma cornicina cornicina (Linnaeus, 1758) (China: as far south as Zhejiang; widely distributed in Palaearctic Region)
62 (59)	Caudal margin of male tergite nine with two intermediate rounded processes and two spinous processes laterally (see Yang and Yang 1990: p. 124, fig. 2B)	Nephrotoma kunagi Yang & Yang, 1990 (China: Sichuan)
–	Caudal margin of male tergite nine with processes not as above	63
63 (62)	Cell m1 petiolate (see Alexander 1927: p. 182)	Nephrotoma pleuromaculata Alexander, 1927 (China: Hubei, Sichuan, Yunnan; India)
–	Cell m1 sessile	64
64 (63)	Intermediate lobes of male tergite nine with apex further produced into a pale triangular point (see Alexander 1935c: Pl. IV, fig. 43)	Nephrotoma martynovi Alexander, 1935 (China: Hebei, Heilongjiang, Inner Mongolia; Russia; Mongolia)
–	Intermediate lobes of male tergite nine with apex lacking such a point	65
65 (64)	Male tergite nine with a slender glabrous spine arising from the ventrolateral portion (see Alexander 1937: p. 25, fig. 29, as brierei)	Nephrotoma scalaris parvinotata (Brunetti, 1918) (China: Beijing, Hebei, Shanxi, Shandong, Xinjiang, Inner mongolia, Gansu, Ningxia, Heilongjiang, Jiangsu, Anhui, Sichuan, Guizhou; Russia; Georgia; Armenia; Azerbaijan; Turkey; Syria; Lebanon; Iran; Kazakhstan; Turkmenistan; Uzbekistan; Tajikistan; Kyrgyzstan; Afghanistan; Mongolia; India; Pakistan)
–	Male tergite nine without such a spine arising from the ventrolateral portion (see Oosterbroek 1985: p. 259, fig. 72)	Nephrotoma pullata (Alexander, 1914) (China: Heilongjiang; Russia; North Korea; Japan)
66 (29)	Male sternite eight with a small compressed lobe at posterior margin (see Alexander 1935a: p. 139)	Nephrotoma pilata Alexander, 1935 (China: Sichuan)
–	Male sternite eight lacking such a lobe at posterior margin (see Alexander 1949: p. 519)	Nephrotoma vesta Alexander, 1949 (China: Guangdong)
67 (57)	Abdominal tergites black with pale yellow lateral stripes	69
–	Abdominal tergites yellow with dark lateral stripes	70
68 (57)	Inner gonostylus without crest	71
–	Inner gonostylus with crest	72
69 (67)	Antennae entirely black; male tergite nine terminating in two rounded lobes at caudal margin (see Alexander 1935a: Pl. IV, fig. 49)	Nephrotoma biformis Alexander, 1935 (China: Sichuan)
–	Antennae entirely brown; male tergite nine terminating in two acute lobes at caudal margin (see Yang and Yang 1990: p. 481, Pl. V, fig. 2)	Nephrotoma joneensis Yang & Yang, 1990 (China: Gansu)
70 (67)	Cell m1 petiolate (see Yang and Yang 1987: p. 245)	Nephrotoma barbigera (Savchenko, 1964) (China: Heilongjiang, Jilin, Gansu, Ningxia, Shanxi; Russia)
–	Cell m1 sessile	77
71 (68)	Male tergite nine with a pair of spinous processes except setae	73
–	Male tergite nine without spinous processes except setae (see Oosterbroek 1985: p. 262, fig. 79)	Nephrotoma bifusca Alexander, 1920 (China: Heilongjiang, Hebei, Jilin; Russia; North Korea; South Korea; Japan)
72 (68)	Cell m1 petiolate	75
–	Cell m1 sessile	76
73 (71)	Male tergite nine projected into a pair of spike-like processes at caudal margin, each with a series of six or seven blackened points along their medial edge (see Savchenko 1973: p. 47)	74
–	Male tergite nine projected into a pair of fingerlike processes at caudal margin, the horn without points described as above (see Yang and Yang 1990: p. 480, Pl. IV, fig. 2)	Nephrotoma shanxiensis Yang & Yang, 1990 (China: Shanxi)
74 (73)	Cell m1 petiolate (see Alexander 1935a: Pl. I, fig. 19)	Nephrotoma impigra impigra Alexander, 1935 (China: Zhejiang, Hubei, Jiangxi, Fujian, Sichuan)
–	Cell m1 sessile (see Savchenko 1973: p. 48)	Nephrotoma impigra fulvovittata (Savchenko, 1964) (China: Yunnan)
75 (72)	Male tergite nine terminating in two angular lobes at caudal margin (see Tangelder 1984: p. 74, fig. 235)	Nephrotoma quadristriata (Schummel, 1833) (China: Xinjiang; widely distributed in Palaearctic Region)
–	Male tergite nine terminating in two truncated lobes at caudal margin (see Tangelder 1984: p. 49, fig. 115)	Nephrotoma spicula Tangelder, 1984 (China: Heilongjiang; Russia; North Korea)
76 (72)	Inner gonostylus with crest toothed (see Tangelder 1984: p. 77, fig. 245)	Nephrotoma scurra (Meigen, 1818) (China: Gansu, Inner Mongolia; widely distributed in Palaearctic Region)
–	Inner gonostylus with crest not toothed (see Tangelder 1984: p. 28, fig. 20; p. 30, fig. 29; p. 38, fig. 73)	78
77 (70)	Male tergite nine terminating in two truncated lobes at caudal margin; inner gonostylus with an angular process on dorsal side (see Mannheims 1967: p. 178, fig. 1)	Nephrotoma ligulata Alexander, 1925 (China: Xinjiang; Russia; Turkmenistan; Uzbekistan; Tajikistan; Kyrgyzstan; Afghanistan; Mongolia; India)
–	Male tergite nine terminating in two bluntly rounded lobes at caudal margin; inner gonostylus without process on dorsal side (see Yang and Yang 1987: p. 244, figs. 3B, 3C)	Nephrotoma xinjiangensis Yang & Yang, 1987 (China: Xinjiang)
78 (76)	Male sternite nine with an appendage directed caudally (see Alexander 1953: p. 332, fig. 3a)	Nephrotoma kaulbacki Alexander, 1951 (China: Xizang)
–	Male sternite nine with an appendage directed ventrally (see Tangelder 1984: p. 28, fig. 16; p. 30, fig. 27)	79
79 (78)	Abdominal tergites without lateral stripes; male tergite nine separated by a U-shaped notch medially on caudal margin (see Tangelder 1984: p. 30, fig. 30)	Nephrotoma perobliqua Alexander, 1936 (China: Gansu)
–	Abdominal tergites with lateral stripes; male tergite nine separated by a V-shaped notch medially on caudal margin (see Tangelder 1984: p. 28, fig. 18)	Nephrotoma pjotri Tangelder, 1984 (China: Xinjiang; Kazakhstan; Uzbekistan; Kyrgyzstan)