Megalinus flavus ( Bordoni, 2002 )

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 : 35-38

Megalinus flavus ( Bordoni, 2002)

(Fig. 11A–H; Fig. 11-1A–H)

Bordoni, 2002: 652 ( Lepidophallus ; Type locality: China, Fujian, Shaowu; 500 m); Bordoni, 2003c: 269 (Fujian, Guizhou, Hong Kong); Bordoni, 2007b: 70 (catalog; Fujian, Guizhou, Hongkong); Bordoni, 2008: 58 ( Megalinus ; species list of Megalinus ).

Type material: male, with labels as follows: “ HOLOTYPUS, Lepidophallus , flavus BORDONI 2002 ” / “Shaowu - Fukien, (500m) J. Klapperich, 13.11.1937 ” / “ Lepidophallus , suffusus (Sharp) , det. A.Bordoni 1995” ( NMW).

Addtional materials: CHINA: Jiangxi: Fuzhou: Linchuan District , 5 males, 3 females, 04.XI.2011 , 50 m, Zhou Jianhua & Zhou Yulingzi collected; one male, one female, 16. V.2011; 2 males, 18. V.2011; one male, 06.XI.2011; one male, 16. V.2010 ( IZ-CAS); Jinggangshan city: Ciping Town , 2 males, 22.X.2010 , Pemg, Zhai & Zhu collected ( CB) ; Hubei: Zigui co.: Maoping Town (E 110.9720, N 30.8236), two males, 170 m, 28. IV.1994, Zhang Youwei collected; Zhejiang: Kaihua co.: Gutianshan Nature Reserve (E 118.1454, N 29.2572), 3 males, 4 females, 14. V.2008, Zhao Zongyi collected; one male, 16. V.2008; Shanghai: one male, one female; 2 males, 21.VII.1939 ; one male, one female, 01.IX.1939; 2 females, 02.IX.1985; one male, 2 females, 12.XI.1938; one male, 2 females, 03.XI.1963; one male. 27.X.1938; Fujian: Jianyang City: Huangkeng co.: Aotou (E 117.6540, N 27.6668), one female, 05. V.1960, 800– 950 m, Ma Chenglin collected ( IZ-CAS) ; Jiangsu: Suzhou, Yangchen Lake , one male, 25. IV.1998, Li Li-Zhen collected (CT).

Description

Measurements. BL= 6.7 mm, FL= 4.2 mm, HL= 1.2 mm, HW=1.0 mm, PL= 1.4 mm, PW=1.0 mm, EL= 1.4 mm, EW= 1.4 mm.

Body cylindrical, medium to large sized (Fig. 11D). Body dark brown, except elytra lighter. Legs dark brown except tibiae lighter. Antennae entirely dark brown except apical 1/3 of last antennomere lighter. Maxillary and labial palpi brown.

Head (Fig. 11A). Subquadrated (HL to HW ratio 1.1), temple usually widened posteriorly, sometimes distinctly widened, posterior angles rounded. Dorsal integument shiny, without microsculpture, but extensively with micropunctures, also distributed with round, deep, medium-sized punctures, interspaces between punctures 1– 2 punctures’ diameters; additional dense, small punctures often sparsely scattered on surface between eyes, scarcely densely scattered on anterior half of head; posterior half of disc (0.20 mm width) without any punctures. Each side of cranium also with frontal puncture on epistoma, two anterolateral punctures near antennal insertion, two smaller punctures on frontal region, midlateral puncture approximately a distance of 4–5 punctures’ diameter from dorsal margin of eye, temporal puncture and occipital puncture not obvious; deflexed portion of head bearing 2–3 rows of medium sized punctures. Frontal furrows deep and convergent backwards, equal to length of anteocular furrows. Anteocular furrows deep and broader, subequal to eye length, arriving line connecting rearmost of each eye. Eye of large size, 1/2 of temple length (eye: temple = 0.30: 0.66 mm), distinctly protruding laterad. Epistoma protruding forwards, of subrectangular shape, anterior margin subtruncated. Distance between antennal insertions 0.30 mm, slightly wider than that from antenna to eye (0.27 mm).

Antennae. Scape stout, thickened apically, longer than three subsequent antennomeres combined, 0.60 mm; antennomere II elongate, 0.18 mm, slightly longer than III; III elongate, 0.15 mm; IV and V transverse, subequal in length, 0.06 mm; last antennomere of medium length, 0.21 mm, subequal to preceding two antennomeres combined.

Neck. Medium width (0.39 mm), slightly wider than 1/3 of head width.

Pronotum (Fig. 11B). Subrectangular, distinctly elongated (PL to PW ratio 1.4), longer than head, but of equal width. Obviously widened anteriad, lateral margins sinuate, anterior angles well-developed and protruding, posterior angles broadly rounded. Integument shiny, extensively bearing micropunctures, but without microsculpture. Two rows of setiferous punctures presenting on each side, admedian row consisting of 7–9 punctures; lateral row, curvedly arranged, of 5–6 punctures; other irregular punctures scattered near anterior margin.

Mesoscutellum. Shiny, extensively covered with distinct polygonal recticulum, and with several small, irregular punctures.

Elytra (Fig. 11C). Subquadrated (EL to EW ratio 1.0), obviously wider than pronotum, but of same length. Humeri well developed, lateral margins distinctly widened posteriorly, hind margin arcuate. Integument shiny and flattened, without microsculpture; each elytron with 6–8 rows of medium-sized punctures; deflexed portion with 4– 6 rows of smaller setiferous punctures.

Abdomen. Cylindrical, broadest at segment VII. Tergites III–VII shiny, covered with distinct transverse microstriae and small setiferous punctures, interspaces between punctures near 2–3 punctures’ diameter; each segment with basal impression. Surface between two basal transverse carinae impunctate, but bearing distinct polygonal reticulum. All abdominal sternites shiny, with microsculpture and setiferous punctures as those on tergites.

Male. Abdominal segment VIII entirely covered with setiferous punctures, except a narrow medial longitudinal impunctate band; posterior margins of tergite VIII and sternite VIII both slightly protruding backwards or subtruncated (Fig. 11-1A, B). Tergite IX symmetrical, connected mediobasally. Sternite IX symmetrical, with bisinuate mediobasal margin and distinctly emarginated posterior margin (Fig. 11E; Fig. 11-1C). Tergite X symmetrical, with subtruncated base and broadly emarginated apex (Fig. 11-1D), in situ broadly exposed between tergite IX. Median lobe of aedeagus subspherical and medium sized (Fig. 11G, H; Fig. 11-1E, F), basal piece without transparent, membranous medial-longitudinal band; basal bulb 1.0 mm long, anterior portion short, narrowed apically, 0.13 mm (Fig. 11F). Parameres symmetrical and thin, slightly shorter than 1/3 of basal bulb length. Internal sac with board and dark brown processes composed of small and large spines, apex with fine paired rows of spines.

Female. Posterior margin of sternite VIII (Fig. 11-1G) laterally arcuate connected with subtruncated medial part. Genital segment medium sized (Fig. 11-1H), 0.77 mm long, sternite with bisinuate basal margin; supplementary sclerites symmetrical, subtriangular, and medium sized of 0.30 mm long, overlapped most part of basal margin of genital sternite.

Distribution. China (Hubei, Zhejiang, Shanghai, Fujian, Jiangxi).

Remarks. The holotypus of Megalinus flavus ( Bordoni, 2002) was not dissected. Thanks to the curator who gave us permission to study and dissect the holotype, we found that the description of M. flavus ( Bordoni, 2002) is not corresponding to the original description of the holotype, including punctures distribution on head, male abdominal sternite IX, tergite X and median lobe of aedeagus, etc. So, we redescribed M. flavus ( Bordoni, 2002) to make the description more accurate to help with its identification. This species could be distinguished from its congeners by: 1) distributed pattern of punctures on head; 2) eye of large size; 3) the number of lateral row of punctures on pronotum; 4) distinctly protruding anterior angles of pronotum; 5) male tergite X shape; 6) internal sac with board and dark brown processes composed of small and large spines, apex with fine paired rows of spines.

segments, ventral view. Scale bars 0.30 mm.