Pseudobironium Pic, 1920

Löbl, Ivan & Tang, Liang, 2013, A review of the genus Pseudobironium Pic (Coleoptera: Staphylinidae: Scaphidiinae), Revue suisse de Zoologie 120 (4), pp. 665-734 : 667-679

Pseudobironium Pic, 1920

Pseudobironium Pic, 1920a: 15 . Type species Pseudobironium subovatum Pic, 1920 , by monotypy.

Morphoscapha Achard, 1920: 131 . Type species Morphoscapha grossum Achard, 1920 , by original designation.

REMARKS: The description of the genus appeared twice in 1920, the first time in the number 400 of Echange, dated “juillet-août”, the second time under the synonymous Morphoscapha in the Annales of the Belgian entomological society, issued on October 1, 1920. Pseudobironium was redescribed by Löbl (1969), and its features and relationships were discussed by Leschen & Löbl (2005). The genus is characterized by the combination of the following characters: Body broad, antennomere III elongate, VIII not or slightly smaller than VII and IX, apical maxillary palpomere normal, pronotum with anterior bead complete, basal pronotal angles not prominent and not reaching metanepisterna, basal lobe of pronotum large, corbiculum present, mesepimera concealed, metanepisterna narrow and with deep suture, elytra with complete basal striae, profemora lacking ctenidium, tibiae robust, abdominal sternite 1 with lateral impressions, submetacoxal lines absent.

Four tentative species groups may be distinguished based on characters of the internal sac of the aedeagus:

The P. plagiferum group: the internal sac is membranous except for elongate guide-sclerite surrounding the ejaculatory duct in the middle part of the median lobe. Species included (3): P. javanum sp. nov., P. plagiferum Löbl , and P. spinipes sp. nov.

FIGS 1-2 Pseudobironium spinipes sp. nov. (1), metaventrite (2); scale bars = 1 mm. FIGS 3-4 Pseudobironium fujianum sp. nov. (3), metaventrite (4); scale bars = 1 mm. FIGS 5-6 Pseudobironium merkli sp. nov. (5), metaventrite (6); scale bars = 1 mm. FIGS 7-8 Pseudobironium confusum sp. nov. (7), metaventrite (8); scale bars = 1 mm. FIGS 9-10 Pseudobironium feai Pic (9), metaventrite (10); scale bars = 1 mm. FIGS 11-12 Pseudobironium carinense (Achard) (11), metaventrite (12); scale bars = 1 mm.

The P. merkli group: with elongate guide-sclerite as in the former group, lacking flagellum, and with paired, fine admesal plates. Species included (4): P. fujianum sp. nov., P. merkli sp. nov., P. montanum sp. nov. and P. schuhi sp. nov.

The P. fasciatum group: the internal sac has a distinct, very long flagellum not protruding in repos, and additional lateromedian sclerotized pieces. Species included (7): P. augur sp. nov., P. brancuccii sp. nov., P. fasciatum Löbl , P. flagellatum sp. nov., P. impressipenne Löbl , P. ineptum Löbl and P. rufitarse Löbl.

The P. subovatum group: the flagellum is absent, the internal sac has narrow mesal guide-sclerites surrounding the ejaculatory duct, and additional lateromesal sclerotized pieces. These are paired and subsymmetrical, each usually consisting of one or two cylindrical rods invaginated in a conical sclerite. Additional mesal sclerites may be present. The bulk of the species (25) belongs to this group.

Within the latter group two subgroups may be distinguished, based on the parameres and apical process of the median lobe. The parameres are narrow posteriad base, and the lateral and ventral sides of the median lobe are smooth, or almost smooth, in P. almoranum Champion , P. banonense (Pic) , P. bicolor Löbl , P. bilobum sp. nov., P. feai Pic , P. horaki sp. nov., P. incisum sp. nov., P. languei (Achard) , P. lewisi Achard , P. parabicolor sp. nov., P. pseudobicolor sp. nov., P. pubiventer sp. nov., P. sparsepunctatum (Pic) , P. stewarti sp. nov., P. subglabrum Löbl , and P. ussuricum Löbl.

The parameres are strongly widened posteriad base, and the lateral or ventral sides of the apical process of the median lobe are usually tuberculate in P. antennatum sp. nov., P. carinense (Achard) , P. confusum sp. nov., P. conspectum sp. nov., P. convexum sp. nov., P. grossum (Achard) , P. hisamatsui Löbl , P. subovatum Pic and P. vitalisi (Achard) . They have also strongly sclerotized aedeagi with large basal bulb, features however not exclusive to these species.

Two similar species, P. sparsepunctatum (Pic) and P. languei (Achard) , possess short and broad maxillary palpi (see Löbl, 1982b and 2012b), defined as papillate in Leschen & Löbl, 2005. They share comparatively short antennae and their body is weakly convex dorsally. Therefore, they were considered as a possible sister group of the remaining congeners. Their aedeagal characters suggest relationships to P. subovatum Pic and its allied. In addition, similar antennae and comparatively weakly convex body are also in some other species, such as P. achardi (Pic) and P. ussuricum Löbl.

Following species represented in collections by females only are unplaced: P. achardi (Pic) , P. sinicum Pic , and species A.

KEY TO SPECIES OF PSEUDOBIRONIUM

1a Ventral mesotibial spur straight in basal half, conspicuously bent in apical half. Body uniformly reddish-brown. Zhejiang ....... P. spinipes sp. nov.

1b Ventral mesotibial spur straight or barely bent. Body often black or pronotum and/or elytra with particular colour pattern................... 2

2a Maxillary palpus short and robust, with apical palpomere about twice as long as broad, not narrowed from base to mid-length. Body black, moderately convex dorsally. Apicolateral parts of abdominal sternite coarsely punctate, sternite 2 wrinkled basolaterally.................... 3

2b Maxillary palpus elongate, with apical palpomere more than twice as long as broad and usually tapering. Body often reddish or with particular colour pattern, and convex dorsally. Apicolateral parts of abdominal sternite 1 usually very finely punctate and sternite 2 usually lacking distinct basolateral wrinkles (present in P. ussuricum ).................. 4

3a Aedeagus with tip of median lobe blunt, weakly inflexed; parameres in lateral view about 17 or 18 times as long as in middle wide. Greater Sunda Islands , Palawan ....................... P. sparsepunctatum (Pic)

3b Aedeagus with tip of median lobe abruptly inflexed, almost hook-like; parameres in lateral view about 10 times as long as wide in middle. Malay Peninsula, Thailand, Laos, Vietnam, Taiwan...... P. languei (Achard)

4a Pronotum and/or elytra clearly bicolorous, often with conspicuous colour pattern................................................. 5

4b Pronotum and elytra reddish-brown to black, lacking particular colour pattern, elytral apices sometimes slightly darkened or lightened.......... 13

5a Lateral parts of metaventrite and of abdominal sternite 1 lacking microsculpture.................................................... 6

5b Lateral parts of metaventrite and of abdominal sternite 1 distinctly microsculptured............................................... 9

6a Center of elytral disc black, surrounded by light, yellowish or reddish area, pronotum distinctly bicolorous. Taiwan............ P. plagiferum Löbl

6b Elytral coloration different, pronotum uniformly reddish-brown to black, or becoming slightly lighter laterally............................... 7

7a Antennae short, antennomeres III, IV and VI even in length. Elytra dark, with light apical area. Sumatra ......................... P. achardi (Pic)

7b Antennae long, antennomere III much shorter than IV and VI............ 8

8a Elytra each with light fascia parallel to lateral margins, lacking subapical reddish spot. South India............................ P. fasciatum Löbl

8b Elytra each with small subapical reddish spot, not becoming light laterally. South India..................................... species A

9a Pronotum and elytra distinctly maculate............................ 10

9b Pronotum and elytra lacking distinct spots, pronotum becoming lighter toward lateral margins, elytra light posterior humeral area and in apical third to half. Punctation much coarser on elytra than on pronotum. Vietnam........................................ P. stewarti sp. nov.

10a Aedeagus with parameres curved, not widened apically in lateral view..... 11

10b Aedeagus with parameres straight, widened apically in lateral view....... 12

11a Basal bulb of aedeagus shorter than apical process of median lobe. Parameres weakly curved in lateral view. Indonesia: Greater Sunda Islands.......................................... P. horaki sp. nov.

11b Basal bulb of aedeagus longer than apical process of median lobe. Parameres in lateral view strongly curved. Himalaya, Meghalaya, Thailand.......................................... P. bicolor Löbl

12a Apical part of parameres subtriangular in dorsal view, with apex acute, strongly widened and folded in lateral view. Yunnan ... P. parabicolor sp. nov.

12b Apex of parameres rounded in dorsal view, not folded in lateral view; parameres gradually widened toward level of tip of median lobe in lateral view. Taiwan.......................... P. pseudobicolor sp. nov.

13a Lateral parts of metaventrite and abdominal sternite 1 with conspicuous coarse punctures. Far East Russia, Korea, Anhui, Yunnan... P. ussuricum Löbl

13b Lateral parts of metaventrite and abdominal sternite 1 very finely punctate. 14

14a Elytra each with shallow, narrow lateral impression starting shortly posterior base and reaching about mid-length, with punctures very dense and conspicuously coarser than those on surrounding elytral surface. Sumatra ..................................... P. impressipenne Löbl

14b Elytra lacking elongate lateral impression........................... 15

15a Antennae short, antennomere XI not more than twice as long as wide. Small species, body length not exceeding 2.3 mm ..................... 16

15b Antennae long, antennomere XI usually distinctly more than twice as long as wide. Usually larger species, with body length often exceeding 2.5 mm ..................................................... 17

16a Most of elytra coarsely punctate, with punctures much coarser that those on pronotum. Body black. Antennomere V as long as VI. Himalaya............................................. P. almoranum Champion

16b Most of elytra finely punctate, with punctures similar to those on pronotum, distinctly coarser only near apices. Body dark reddish-brown. Antennomere V almost 1.5 times as long as VI. Thailand.. P. subglabrum Löbl

17a Prohypomera with dense, distinct undulate microsculpture. Vietnam, Yunnan......................................... P. merkli sp. nov.

17b Prohypomera lacking undulate microsculpture....................... 18

18a Submesocoxal area about as long as shortest interval to metacoxa. Fujian .................................................. S. sinicum Pic

18b Submesocoxal area much shorter than shortest interval to metacoxa....... 19

19a Apical antennomere conspicuously elongate, about 1.5 times as long as penultimate antennomere and about 4.5 to 5 times as long as wide. Large species, body about 3.3 to 4.0 mm long, black or almost black (see Note above for P. grossum ).......................................... 20

19b Apical antennomere not so long, usually about 1.2 to 1.3 times as long as penultimate antennomere and about 3 to 4 times as long as wide. Species often smaller.......................................... 22

20a Metaventrite with two elongate admesal tubercles. Hainan, Vietnam................................................ P. confusum sp. nov.

20b Metaventrite without tubercles................................... 21

21a Metacoxal process not microsculptured, swollen at base. Parameres in lateral view narrowed from base toward inflexed apical section, and with concave upper margin. Malay Peninsula............. P. antennatum sp. nov.

21b Metacoxal process microsculptured, with basomedian tubercle. Parameres in lateral view not narrowed toward inflexed apical section, and with upper margin weakly sinuate. Laos.......... P. grossum (Achard)

22a Metaventrite on apicomedian part and/or posterior submesocoxal lines with strigulate microsculpture.................................... 23

22b Metaventrite without microsculpture............................... 26

23a Aedeagus with tip of parameres bent mesally and hook-like in dorsal view, almost straight and in basal halves weakly expanded dorsally in lateral view. Philippines............................ P. banonense (Pic)

23b Aedeagus with tip of parameres not hook-like in dorsal view............ 24

24a Prohypomera conspicuously pubescent. Metacoxal process swollen in middle. Body reddish-brown, 2.2 mm long. Borneo.... P. pubiventer sp. nov.

24b Prohypomera smooth, or with extremely short, inconspicuous pubescence.. 25

25a Tip of median lobe knob-like in lateral view. Meghalaya, Myanmar, Laos, Guangxi, Xizang, Hainan............................ P. feai Pic

25b Tip of median lobe hook-like in lateral view. Yunnan ... P. montanum sp. nov.

26a Abdominal sternite 1 with microsculpture covering entire or almost entire surface and distinct also near its apicolateral margins............. 31

26b Abdominal sternite 1 lacking microsculpture, or with microsculpture limited onto its median area..................................... 27

27a Pronotal and elytral punctation similar, very fine, sometimes indistinct. Small species 2. 0 to 2.4 mm long. Body black. Aedeagus with parameres wide and gradually narrowed toward apices in lateral view, apices widened and curved in dorsal view. Membranes of the internal sac with two admesal rows of long spine-like structures. Java ....... P. schuhi sp. nov.

27b Elytral punctation distinct, coarser than pronotal punctation. Larger species, 2.4 to 3.0 mm long. Body reddish-brown to black.............. 28

28a Antennomere II distinctly longer than III. Median part of abdominal sternite 1 not microsculptured. Parameres of aedeagus sinuate in lateral view. Himalaya, Meghalaya ....................... P. brancuccii sp. nov .

28b Antennomeres II and III even or almost even in length. Median part of abdominal sternite 1 microsculptured.............................. 29

29a Parameres narrow, almost straight in lateral view..................... 30

29b Parameres fairly wide, arcuate in dorsal and lateral views. Laos.................................................. P. flagellatum sp. nov.

30a Body reddish-brown. Antennomere XI almost 3 times as long as wide. Inflexed tip of median lobe very short. Parameres in dorsal view almost straight. Himalaya.................................. P. ineptum Löbl

30b Body blackish-brown to black. Antennomere XI about 2.5 times as long as wide. Inflexed tip of median lobe fairly long. Parameres distinctly curved in dorsal view. Japan.......................... P. augur sp. nov.

31a Punctation on inferior part of prohypomera clearly more dense and distinct than that on superior part of prohypomera. Japan.... P. lewisi Achard

31b Prohypomera with even or almost even and very fine punctation, often appearing impunctate.......................................... 32

32a Male protarsus about as long as or longer than protibia, with tarsomeres 2 and 3 each longer than 1, and tenent setae much longer than respective tarsomeres. Apex of median lobe abruptly curved and acute, parameres strongly narrowed from base toward mid-length. Thailand, Malay Peninsula, Greater Sunda Islands...................... P. subovatum Pic

32b Male protarsus shorter than protibia, with tarsomeres 2 and 3 not conspicuously elongate, each about as long as tarsomere 1, tenent setae not or moderately longer than respective tarsomeres........................ 33

33a Entire median part of metaventrite densely punctate, centre of metaventrite with foveiform impression. Apical part of parameres gradually widened and bent dorsally in lateral view. Internal sac lacking additional sclerites situated posterior mesal guide-sclerites. Java ..... P. javanum sp. nov.

33b Narrow mesal stripe of metaventrite smooth, metaventrite without foveiform impression. Apical part of parameres not bent dorsally, usually not widened. Internal sac with sclerites situated posterior mesal guide-sclerites............................................... 34

34a Aedeagus with flagellum, parameres conspicuously sinuate in dorsal view. Body black, tarsi reddish, much lighter than body. Himalaya..................................................... P. rufitarse Löbl

34b Aedeagus without flagellum, parameres not or weakly sinuate in dorsal view. Body usually dark reddish-brown, tarsi lighter than body, not reddish..................................................... 35

35a Aedeagus with parameres notched subapically. Vietnam.... P. incisum sp. nov.

35b Aedeagus with parameres not notched............................. 36

36a Median lobe of aedeagus with a pair of dorsolateral, membranous, elongate lobes. Parameres widened apically in dorsal view, almost evenly arcuate in lateral view. Malay Peninsula............... P. bilobum sp. nov.

36b Median lobe of aedeagus without dorsolateral lobes................... 37

37a Tip of median lobe of aedeagus narrow and acute in lateral view. Body length 2.4-3.2 mm. China: Fujian .................... P. fujianum sp. nov.

37b Tip of median lobe of aedeagus robust and often truncate in lateral view. Larger species, body length 3.1-4.5 mm ............................ 38

38a Parameres with upper margin broadly arcuate in lateral view............ 39

38b Parameres with upper margin not or only shortly arcuate in lateral view... 40

39a Parameres in apical half uneven, distinctly narrowed near apices, with ventral margin sinuate in lateral view. Internal sac with long mesal guide-sclerites and, in addition to other sclerotized pieces, pair of small, mesally bent sclerites. South India, Himalaya, Myanmar, Thailand, Laos, Yunnan...................................... P. conspectum sp. nov.

39b Parameres in apical half evenly curved and wide in lateral view. Internal sac with short mesal guide-sclerites and lacking additional, mesally bent sclerites. Greater Sunda Islands, Sipura, Malay Peninsula, Lankawi, Vietnam,?Hainan.............................. P. convexum sp. nov.

40a Parameres not conspicuously widened basally, with dorsal and ventral margins parallel in middle third, in lateral view. Median lobe of aedeagus with inconspicuous lateral tubercles. Taiwan......... P. hisamatsui Löbl

40b Parameres conspicuously widened basally, with dorsal and ventral margins converging in middle third, in lateral view. Median lobe of aedeagus with distinct lateral tubercles............................. 41

41a Parameres in lateral view distinctly expanded dorsally to form a lobe, with apical section shorter than third of total parameral length. Internal sac with globular vesicles. Myanmar, Thailand, Laos, Vietnam, Yunnan............................................. P. carinense (Achard)

41b Parameres in lateral view subangulate, not lobed dorsally, with apical section about as long as third of total parameral length. Internal sac without globular vesicles........................................ 42

42a Tip of aedeagus narrow and weakly bent in lateral view. Parameres each with mesal lobe visible in dorsal view. Laos............ P. gossum (Achard)

42b Tip of aedeagus thick and not bent in lateral view. Parameres without mesal lobe. Greater Sunda Islands,? Laos.............. P. vitalisi (Achard)