Anthobium crassum Shavrin & Smetana, 2019

Shavrin, Alexey V. & Smetana, Aleš, 2019, A revision of Eastern Palaearctic Anthobium Leach, 1819 (Coleoptera: Staphylinidae: Omaliinae: Anthophagini). III. Consanguineum, crassum and reflexum groups, and an additional species of the fusculum group, Zootaxa 4688 (4), pp. 451-482 : 460-463

Anthobium crassum Shavrin & Smetana , sp.n.

( Figs. 4, 7, 10, 13 , 16, 19, 22, 25, 28, 31, 34 , 37, 40, 43, 46 , 49, 56, 60–61, 64–66)

Type material examined: Holotype ♂: ‘ CHINA: N-Yunnan Zhongdian | Co. 10km SW Zhongdian, Xue | Shan

27°46.5’N 99°36.5’E | 3800m 20.VIII.2003 | A. Smetana [C129]’ <rectangular label, printed>, ‘ HOLOTYPE | An- thobium | crassum sp.n. | Shavrin A.V. & Smetana A. 2018’ <red rectangulat label, printed> ( NSMT).

Paratypes (14 specimens): 1 ♀ [dissected]: ‘ CHINA: N-Yunnan Diqing Tibet | Aut.Pr.Zhongdian Co. Xue Shan | near lake, 23 km S Zhongdian | 27°37.1’N 99°38.5’E 3895m | 15. VI.2005 A. Smetana [C161]’ <rectangular label, printed> ( NSMT) ; 2 ♂♂ [one specimen dissected], 3 ♀♀: ‘ CHINA: N-Yunnan [C2005-05A] | Diqing Tibet. Aut. Pref. , | Zhongdian Co., Xue Shan near | lake 23 km S Zhongdian, 3895 m’ <rectangular label, printed>, ‘ 27°37.1’N, 99°38.5’ E, devast[ated]. | mixed forest, meadows, lake | border, leaf litter, dead wood, | sifted, 6. VI.2005, | leg. M. Schülke [C2005-05A]’ <rectangular label, printed> ( CS; CSC) ; 2 ♂♂ [one specimen dissected]: ‘ CHINA: N- Yunnan [C2005-05B] | Diqing Tibet. Aut. Pref. , | Zhongdian Co., Xue Shan near | lake 23 km S Zhongdian, 3895 m’ <rectangular label, printed>, ‘ 27°37.1’N, 99°38.5’ E, devast[ated]. | mixed forest, meadows, lake | border, leaf litter, dead wood, | sifted, 15. VI.2005, | leg. M. Schülke [C2005-05B]’ <rectangular label, printed> ( CSC; CS) ; 1 ♂ [dissected], 1 ♀: ‘ CHINA (N-Yunnan) Zhongdian | Co., Xue Shan , 10 km SW | Zhongdian , 3700-3800m, | 27°46.5’N / 99°36.5’E (primary | mixed forest, leaf litter sifted) | 20.VIII.2003 [D.] Wrase [10A]’ ( CSC) ; 1 ♂ [dis- sected]: ‘ CHINA N Yunnan, Xue | Shan nr. Zhongdian | 4000-4100 m 23. VI.96 | 27°40N 99°34E C36’ <rectangular label, printed>, ‘collected by | A. Smetana, J. Farkač | and P. Kabátek’ <rectangular label, printed> ( NSMT) ; 1 ♂ [dissected]: ‘ CHINA N Yunnan, Xue | Shan nr. Zhongdian | 4050m 24. VI.1996 | 27°49N 99°34E C40’ <rectangular label, printed>, ‘collected by | A. Smetana, J. Farkač | and P. Kabátek’ <rectangular label printed> ( CS) ; 1 ♂ [dis- sected]: ‘ CHINA, Yunnan, Haba | Shan, N 27°21’01’’ | E100°05’44’’, 4072m, | 28.vi.2012, sift35 | V. Grebennikov’ <rectangular label, printed> ( CNC) ; 1 ♀: ‘ CHINA, Yunnan, | Haba Shan, N 27°20’58’’ | E100°05’58’’, | 19.vi.2012, 4114m, | sift24, V. Grebennikov’ <rectangular label, printed> ( CNC) . All paratypes with additional red rectangular printed label : ‘ PARATYPE | Anthobium | crassum sp.n. | Shavrin A.V. & Smetana A. 2018’.

One specimen with destroyed apical portion of elytra and abdomen was not included in the type series, it was dissected and used for the preparing of Figs. 16, 19, 22, 25, 28, 31, 34 of the body parts; label of this specimen: ‘ CHINA N Yunnan, Xue Shan nr. Zhongdian 4050m 24. VI .1996 27°49N 99°34E C40’, ‘collected by A. Smetana, J. Farkač and P. Kabátek’ ( CS).

Description. Measurements (n=15): HW: 0.65–0.70; HL: 0.37–0.41; AL: 1.19; OL: 0.15–0.18; PL: 0.47–0.50; PW: 1.08–1.27; ESL: 1.17–1.50; EW: 1.37–1.61; AW: 1.10–1.32; MTbL: 0.57; MTrL: 0.25 (MTrL 1–4: 0.15; MTrL 5: 0.10); AedL: 0.62–0.72; TL: 2.62–3.12 (holotype: 2.66).

Body small, robust, convex. Body and antennomeres 7–11 reddish-brown to brown, usually with lateral portions of pronotum and elytra yellow-brown and somewhat paler abdomen; mouthparts, antennomeres 1–6 and legs yellow. Body shiny; forebody without microsculpture except for posterior part of infraorbital ridges, with indistinct diagonal meshes between punctures; abdomen with indistinct to distinct transverse or isodiametric microsculpture. Head with irregular, large and deep punctation, markedly denser between grooves in front of ocelli, denser and finer on infraorbital ridges, usually with small transverse impunctated portions in middle; neck with regular, moderately dense and deep punctation; pronotum with dense punctation, somewhat larger than that on middle portion of head, finer on medioapical fourth, distinctly sparser on mediobasal and sometimes denser on lateral portions, and with variable, more or less wide impunctated area on mediobasal third in some specimens; scutellum with several very fine punctures; punctation of elytra dense, somewhat larger and deeper than that on pronotum, sparser and finer on parascutellar portion, with interspaces between punctures in middle as long as diameter of one or two nearest punctures, each elytron bearing six very vague and tangled longitudinal rows of punctures, replaced by confluent punctures in some paratypes; abdominal tergites with very fine and sometimes indistinct regular punctation. Body glabrous; clypeus with several semierect, moderately long tactile setae; anterior part of frons with several irregular small setae; lateral margins of pronotum with several very short setae; abdominal tergites with regular sparse and very short setae. Habitus as in Fig. 56 .

Head small, transverse ( Fig. 16 ), 1.7 times as wide as long; middle portion slightly elevated, with distinct semicircular impression between eyes, with distinct, deep, short or more or less long grooves in front of ocelli, reaching middle or anterior third of eye; surface between punctures on laterobasal portion of infraorbital ridges slightly and irregularly elevated; postocular ridge small, smooth or somewhat acute; anterior portion between antennal insertion and anterior margin of eye with indistinct semicircular notch. Eyes large, convex. Ocelli moderately large, situated at level of postocular ridges; distance between ocelli slightly longer than distance between ocellus and posterior margin of eye. Labrum small, with widely rounded membranous latero-apical portions, deep apical emargination and elongate basolateral projections ( Fig. 4 ). Mandibles short, moderately narrow, with distinct small tooth in middle of right mandible ( Fig. 7 ). Submentum and labium narrow, with very transverse preapical labial palpomeres ( Fig. 13 ). Apical segment of maxillary palp slightly more than twice as long as preceding segment; galea and lacinia moderately wide ( Fig. 10 ). Gular sutures with shortest distance between posterior third of eyes ( Fig. 16 ). Antenna exceeding shoulders of elytra when reclined; length × width of antennomeres (holotype): 1: 0.14 × 0.07; 2: 0.11 × 0.06; 3–6: 0.10 × 0.05; 7–8: 0.10 × 0.05; 9–10: 0.08 × 0.05; 11: 0.16 × 0.06.

Pronotum transverse, about twice as wide as long, 1.6–1.8 times as wide as head, widest at about middle, evenly narrowed both anteriad and posteriad; apical margin distinctly narrower than posterior margin; anterior angles somewhat rounded, strongly protruded anteriad; posterior angles acute; basal margin of pronotum widely rounded ( Fig. 19 ); lateral margins of pronotum with four irregular, tooth-shaped projections (indistinct in some paratypes), and additional irregular, small lateral crenulation on edges; pronotum with wide elevated middle portion, usually with wide and deep longitudinal impression (indistinct in some specimens), with indistinct or distinct, moderately deep semioval impression on mediobasal third; lateral portions moderately wide and distinctly explanate, each with very deep oval pit approximately in the middle. Prothorax ( Fig. 19 ) with moderately short intercoxal process and narrow protruded mesosternal processes. Mesothorax ( Fig. 28 ) with acute intercoxal process, reaching posterior margin of mesocoxae. Scutellum ( Fig. 22 ) with somewhat acute apex. Metathorax as in Fig. 31 . Metendosternite as in Fig. 34 .

Elytra very convex, relatively short, slightly widened posteriad, about as long as combined wide, reaching basal margin of abdominal tergite VI to VII, with slightly rounded apical margins, truncated at suture; shoulders of elytra widely rounded, not protruded anteriad ( Fig. 25 ); lateral portions of elytra moderately narrow, slightly explanated, latero-apical margins with small, irregular crenulation; surface of each elytron usually with indistinct transverse elevations between punctures in parascutellar portion; some paratypes with indistinct longitudinal impression in mediobasal third along suture. Wings fully developed.

Legs moderately long and slender, tibiae covered by elongate regular setae, with a few strong setae on apical margins near apex; metatarsus distinctly less than twice as long as metatibia.

Abdomen distinctly narrower than elytra, with a pair of small round tomentose wing-folding spots in middle of tergite V; apical margin of abdominal tergite VII with narrow palisade fringe.

Male. Protarsomeres 1–4 slightly widened. Apical margins of abdominal tergite VIII ( Fig. 37 ) and sternite VIII ( Fig. 40 ) slightly emarginate. Aedeagus ( Fig. 60 ) with wide basal portion, gradually narrowed toward rounded apex, with long sclerotized dorsal plate; parameres moderately narrow, long, distinctly exceeding apex of median lobe, with two small apical and preapical setae; internal sac narrow and very long, spirally rolled in basal portion. Aedeagus laterally as in Fig. 61 .

Female. Protarsomeres 1–4 moderately narrow. Apical margin of abdominal tergite VIII straight ( Fig. 43 ). Apical margin of abdominal sternite VIII rounded ( Fig. 46 ). Genital segment as in Fig. 49 .

Comparative notes. Based on the coloration, punctation, shape of the pronotum and general structure of the aedeagus, A. crassum sp.n. is most similar to A. crenulatum sp.n., from which it differs by the smaller body, shorter, slightly widened elytra, narrower aedeagus, with shorter parameres and different internal structures.

Distribution. The species is known from several locations ( Fig. 64 ) in Xue Shan and Haba Shan ranges in Yunnan, China.

Bionomics. Specimens were collected at elevations from 3700 to 4114 m a.s.l. The specimens were taken by sifting rhododendron leaf litter, other leaf litter with humus under it and various floor debris in an original mixed Abies , Betula , tree-like rhododendrons, Ulmus forest with lush deciduous undergrowth (C36), by sifting of needles and various debris under piles of branches of last year cut down Abies trees in remnant of an original Abies , Betula , Rhododendron forest (C161) and fallen leaves and debris under tree-like rhododendrons (C40), by sifting of rotting wood, humus and leaf litter, mostly with mushrooms in various stages of development, in an original Abies , Betula and Rhododendron forest with deciduous shrubbery undergrowth (C129). Some specimens were sifted from leaf litter and dead wood in devastated mixed forests, meadows near border of a lake (locality: C2005-05A ( Figs. 65–66 )).

Etymology. The specific epithet is the Latin adjective crassus, - a, - um (robust, strong). It refers to the robust body of the species.

Figures

FIGURE 64. Distribution of Anthobium crassum (black circles), A. crenulatum (black square), A. explanatum (black rhomb), and A. farkaci (black triangle) in the south-western China.

FIGURES 3–14. Mouthparts (dorsal view) of Anthobium (3, 6, 9, 12—A. consanguineum, 4, 7, 10, 13—A. crassum, 5, 8, 11, 14—A. reflexum): 3–5—labrum, 6–8—mandibles (left and right), 9–11—maxilla (right), 12–14—labium and submentum. Scale bar: 0.1 mm.

FIGURES 15–35. Body parts of Anthobium (15, 18, 21, 24, 27, 30, 33—A. consanguineum, 16, 19, 22, 25, 28, 31, 34—A. crassum, 17, 20, 23, 26, 29, 32, 35—A. reflexum): 15–17—ventral aspect of head, 18–20—ventral aspect of prothorax, 21–23— scutellum (dorsal view), 24–26—ventral aspect of elytron, 27–29—ventral aspect of mesothorax, 30–32—ventral aspect of metathorax (without metanepisternum), 33–35—metendosternite (ventral view). Scale bar: 0.1 mm.

FIGURES 36–47. Abdominal segments of Anthobium (36, 39, 42, 45, 48—A. consanguineum, 37, 40, 43, 46, 49—A. crassum, 38, 41, 44, 47, 50—A. reflexum): 36–38—male tergite VIII (dorsal view), 39–41—male sternite VIII (ventral view), 42–44—female tergite VIII (dorsal view), 45–47—female sternite VIII (ventral view). Scale bar: 0.1 mm.

FIGURES 56–59. Habitus of species of Anthobium crassum-group: 56—A. crassum (holotype), 57—A. crenulatum (holotype), 58—A. explanatum (holotype), 59—A. farkaci (holotype). Scale bar: 1.0 mm.

FIGURES 60–63. Aedeagus of Anthobium crassum (60–61: paratype) and A. crenulatum (62–63: holotype): 60, 62—parameral view, 61, 63—lateral view. Scale bar: 0.1 mm.

FIGURES 48–50. Female genital segment (dorsal view) of Anthobium: 48–A. consanguineum, 49—A. crassum, 50—A. reflexum. Scale bars: 0.1 mm.

FIGURES 65–68. Type locality of Anthobium crassum (65–66), A. crenulatum (67) and A. gaoligongshanense (68) in Yunnan, China (photograph: M. Schülke).