Megalinus Mulsant & Rey

ZHOU, YU-LINGZI, BORDONI, ARNALDO & ZHOU, HONG-ZHANG, 2013, Taxonomy of the genus Megalinus Mulsant & Rey (Coleoptera: Staphylinidae, Xantholinini) and seven new species from China, Zootaxa 3727 (1), pp. 1-66 : 7-8

Key to species of the genus Megalinus Mulsant & Rey from China.

1 Head densely punctate, just with a narrow median longitudinal impunctate ridge (width less than 0.2 mm)............... 2

- Head normally punctate, without a narrow median longitudinal impunctate ridge................................... 8

2 Lateral margins of pronotum distinctly sinuate............................................................... 3

- Lateral margins of pronotum parallel or slightly sinuate....................................................... 4

3 Mesoscutellum bearing isodiameter meshes................................................. M. xingxing Bordoni

- Mesoscutellum bearing transverse microstriae.............................................. M. coracinus (Zheng)

4 Pronotum densely punctate, just with a median longitudinal impunctate region..................................... 5

- Pronotum with paired admedian rows of punctures and paired lateral rows........................................ 7

5 Distance between rows of punctures on pronotum ca. 1/2 of puncture diameter............... M. punctatissimus (Bordoni)

- Distance between rows of punctures on pronotum ca. puncture diameter.......................................... 6

6 Temple gradually dilated............................................................ M. cinnamomeus (Zheng)

- Temples sharply dilated at posterior 1/4................................................ M. taipingensis (Bordoni)

7 Body dark brown, except last abdominal segment yellowish.................................. M. pandarum (Bordoni)

- Body entirely dark brown........................................................... M. tangi Bordoni sp. nov.

8 Median lobe of aedeagus distinctly elongate, length/width> 1.70................................................ 9

- Median lobe of aedeaugs subspherical or elliptical, 1.20<length/width<1.70...................................... 16

9 Paramere possessing hook-like structure.................................................. M. metallicus (Fauvel)

- Paramere without hook-like structure..................................................................... 10

10 Elytra yellowish brown................................................................. M. japonicus (Sharp)

- Elytra brown or dark brown (or reddish brown)............................................................. 11

11 Temple of head substraight............................................... M. nonvaricosus Zhou & Zhou sp. nov.

- Temple of head somewhat dilated or distinctly dilated........................................................ 12

12 Lateral portion of pronotum bearing numerous rows of punctures...................... M. solidus Zhou & Zhou sp. nov.

- Lateral portion of pronotum bearing one row of punctures.................................................... 13

13 Male tergite IX with dark stout spines in inner margins.................................... M. bicatellatus (Bordoni)

- Male tergite IX without dark stout spines in inner margins.................................................... 14

14 Interspaces between head punctures less than two punctures’ diameter........................................... 15

- Interspaces between head punctures more than two punctures’ diameter....................... M. zhenyuanensis (Zheng)

15 Posterior margin of male terigte VIII slightly emarginated or subtruncated....... M. liupanshanensis Zhou & Zhou sp. nov.

- Posterior margin of male terigte VIII medially emarginated.......................... M. ningxiaensis Bordoni , sp. nov.

16 Median lobe of aedeaugs subspherical, 1.20<length/width<1.55................................................ 17

- Median lobe of aedeaugs elliptical, 1.55 <length/width<1.70.................................................. 27

17 Body small, ca. 6 mm; eyes distinctly large, over half of temple length.......................... M. oculatus (Bordoni)

- Body medium sized, over 6 mm; eyes medium sized, ca. 1/3 of temple length..................................... 18

18 Dorsal surface of head sparsely punctate, interspaces between punctures over two punctures’ diameter................. 19

- Dorsal surface of head normally punctate, interspaces between punctures distinctly shorter than two punctures’ diameter.. 20

19 Admedian row of pronotum consisting of 9–11 punctures..................... M. ailaoshanensis Zhou & Zhou , sp. nov.

- Admedian row of pronotum of 16–17 punctures, mixed with some smaller punctures besides......... M. hayashii (Bordoni)

20 Frontal region on head wrinkled, with three paired punctures................................. M. hunanensis Bordoni

- Frontal region on head not wrinkled, with small, densely-distributed punctures.................................... 21

21 Spines on inner sac asymmetrical........................................................................ 22

- Spines on inner sac symmetrical......................................................................... 23

22 Inner sac tape-like, coiled 3–4 times...................................................... M. eremiticus Bordoni

- Inner sac not tape-like, irregularly bearing overlapped spines.................................... M. flavus (Bordoni)

23 Inner sac composing of four groups of symmetrical scales, central two groups 8-shaped, lateral two of four paired large notched structures....................................................................... M. boki (Bordoni)

- Inner sac not shaped as four groups...................................................................... 24

24 Basal 1/3 of inner sac with large paired spines............................................ M. montanicus (Bordoni)

- Basal 1/3 of inner sac without large paired spines........................................................... 25

25 Anterial half of head sparsely punctate, not bearing numerous small punctures................... M. anhuensis (Bordoni)

- Anterial half of head densely punctate, bearing numerous small punctures........................................ 26 27 Male tergite X composed of two parts.................................................. M. pervivagus (Bordoni)

- Male tergite X integrated............................................................................... 28

28 Inner side of male tergite IX bearing stout, dark spines......................................... M. mirus (Bordoni)

- Inner side of male tergite IX without stout, dark spines....................................................... 29

29 Paramere distinctly slender and long, over half of median lobe of aedeagus length............. M. ruficaudatus (Cameron)

- Paramere normally long, shorter than half of median lobe of aedeagus length..................................... 30

30 Inner sac bearing distinct spines......................................................................... 31

- Inner sac without spines, possessing scale-like membrane..................................................... 32

31 Antennomere II distinctly longer than III, inner sac with a row of spines, which becoming distinctly larger towards apex..................................................................................... M. leishanensis (Bordoni)

- Antennomere II equal to length of III, inner sac with two rows of spines, which becoming distinctly larger towards apex............................................................................. M. hailuogouensis Bordoni , sp. nov.

32 Frontal furrows on head subparalleled..................................................... M. solivagus Bordoni

- Anterior 2/3 part of frontal furrows parallel, rest 1/3 convergent together........................... M. suffusus (Sharp)