Sphaerobulbus miwai ( Bernhauer, 1943 ) Hu, 2020

Hu, Fang-Shuo, 2020, New distributional records of Staphylinina in Taiwan, including a new species of Miobdelus Sharp (Coleoptera: Staphylinidae: Staphylininae: Staphylinini), Zootaxa 4768 (3), pp. 334-360 : 342-343

Sphaerobulbus miwai ( Bernhauer, 1943) comb. nov.

( Figs. 11–12 , 28–34 , 52 )

Type material. Lectotype (male, designated here), in FMNH: Nokosan [ Taiwan, Nantou County, Nenggao Mt. ( DZ ḂƜ)], II. V.1919 // miwai Bernh n. sp. [hand writing]// miwai Bernh. Typus, Xanthocypus [hand writing, red label]// Chicago NHMus, M. Bernhauer Collection// FMNHINS 3855894, FILED MUSEUM Pinned [QR code label]. The specimen is in poor condition, remounted on the card, its pronotal disc at the right side bears a hole from the pin. The genital segment was dissected, preserved in glycerin, in a small plastic vial pinned with specimen. Almost both antennae were separated from the head and mounted on the same card, left antenna was missing segment 9–11; right antenna was missing 4 segments, but it is difficult to recognize which segments remain. Tibia of right fore leg and right hind leg, tarsus of right fore leg, right middle leg and right hind leg are missing. Left middle leg was separated from the body and mounted on the same card. Paralectotype (female), in TARI: NUMANOHIRA [ Taiwan, Chiayi County, Chaoping ( ṈṪ), 24-VIII-1927 // Staphylinus miwai Bernh n. sp. [hand writing]. The specimen in very poor condition, remounted on the plastic card, its right elytron bears a large hole from the pin. The genital segment was dissected, mounted on the same plastic card. Nearly both antennae were missing, only first two segments of left antenna remain. Left hind leg, right middle leg right hind leg, tarsus of left fore leg, right fore leg and middle left leg are missing.

Material examined. TAIWAN: Chiayi County: 1 female, Tefuye Historic Trail (Ĥởo古ǎ), Alishan To., 23.4792, 120.8252, 30-IV-2019, leg. H. C. Liu (near creek) (FSHc); 1 male, Shi Mt. race ( ƂƜNJ ửǎ), Alishan To, 23.4731, 120.8458, alt. 2320 m, 08-III-2020, leg. Y. H. Ho (under stone) (FSHc). Nantou County: 2 females, Bilu Mt. Trail (ąn'Ɯṃǎ), Renai To., ca. 2600m, 24.1901, 121.3138, 31-III-2020; leg. F. S. Hu & Y. J. Chen (under rock) (FSHc); 1 male, Meifeng (đø), Renai To., ca. 2113m, 24.0973, 121.1764; 31-III-2020; leg. F. S. Hu & Y. J. Chen (sifting leaf litters) (FSHc); Taichung City: 1 male, Hseuhshan, above Shan-Liu-Gieu Hut [369 Ɯƛ±], 3350m, 10. V.91, A. Smetana [ T 75]// Staphylinus miwai Brnh, Smetana det. 1991 [ NMNS ENT 1283-12] ( NMNS); 1 female, same data as above [ NMNS ENT 1283-2] ( NMNS); 1 spec., same data as above// Ocypus miwai Brnh. det. A. Smetana 1998// Ocypus (Ocypus) miwai Bernh. Det. A. Smetana, 2000 ( FMNH); 1 spec., same data as above// Ocypus (Ocypus) miwai Brnh. Det. A. Smetana 2000 ( FMNH); 1 male, 1 female, same data as above except 3200m, 8–10. V.91, [ T 70] [ NMNS ENT 1283-3; NMNS ENT 1283-4] ( NMNS); 1 female, same data as above except 8. V.91, [ T 72] [ NMNS ENT 1283-13] ( NMNS); 1 male, Tian Pond (Ŧô), Heping Dist., 24.2800, 121.0260 (alt. 2583m), 08-VI-2019, leg. F. S. Hu (under stone) (FSHc); 1 male, same data as above except 23-IX-2018, leg. S. T. Chang (FSHc).

Measurements. BL: 12.07 (11.93–12.21); HL: 1.98 (1.78–2.21); HW: 2.44 (2.22–2.82); EyL: 0.63 (0.58–0.66); TL: 0.95 (0.82–1.20); PL: 2.55 (2.28–2.76); ElL: 2.21 (1.94–2.59) (mm).

Re-description. Small species. Habitus ( Figs. 11–12 ) with dark reddish to piceous-black body; head and neck covered with black to brownish tomentose pubescence, denser on tempora; pronotum, elytra and tergite 3–5 covered with black tomentose pubescence; tergite 6–8 covered with dense yellowish-golden tomentose pubescence, sometimes this pubescence is sparser on tergite 8; femora and tibiae dark red to piceous-black, tarsus brick red; legs covered with paler yellowish-golden tomentose pubescence, denser on fore legs; antennal segments 1–3 black but basal half of segment 2 brick red; segment 4–11 brownish red, gradually become paler.

Head obtusely quadrangular, not dilated posteriad, with rounded posterior angles, wider than long (ratio: 1.23); eyes small, tempora markedly longer than length of eyes in dorsal view (ratio: 1.51); dorsal surface of head densely covered with fine punctation. Antennae moderately long, segment 1 (scape) markedly longer than other segments; segment 2 slightly shorter than segment 1 and segment 3 but markedly longer than other segments; segments 4–10 longer than wide, gradually become shorter; last segment longer than wide, asymmetrically emarginate.

Thorax. Pronotum longer than wide, not dilated in anterior part; lateral margins of pronotum parallel; disc of pronotum with narrow impunctate midline, not obvious anteriorly, with weak expansion in front of posterior margin of pronotum; punctation similar to that of head. Scutellum large, with dense black setae. First four segments of front tarsus markedly dilated, sub-bilobed, covered with dense setae ventrally, sexes not distinctly different. Elytra markedly wider than long; shorter than pronotum (ratio: 0.87); anterior margin of humeral area not dilated; slightly dilated posteriad. Hind wing markedly reduced.

Abdomen. Tergite 7 (fifth visible) without apical palisade fringe; tergite 2 (anterior to first fully visible tergite) with dense setae; general punctation of tergites moderately fine and dense, spread evenly on each tergite.

Male. Sternite 8 ( Fig. 31 ) with obvious, deep and obtuse medioapical emargination; sternite 9 ( Fig. 32 ) without extended basal portion, apical portion with deep and narrow medioapical emargination. Tergite 10 ( Fig. 33 ) subtrapezoidal, with a narrow arcuate apex; numerous brownish setae on posterior margin. Aedeagus ( Figs. 28–29 ) large, with both median lobe and paramere asymmetrical; median lobe in ventral view sub-parallel along most of its length, at about midlength, gradually narrowing to left side; bulbus markedly spherical. Paramere slender, not extended beyond median lobe, slightly wider before apical portion; apical portion of underside of paramere ( Fig. 30 ) without sensory peg setae but bearing few long setae on the margins of both sides apically.

Female genital segment. Tergite 10 ( Fig. 34 ) subtrapezoidal, similar to male tergite 10, apical margin of female tergite 10 more sharply projecting than that of male; setae on apical margin denser than male.

Diagnosis. Due to the relatively small size of Sp. miwai (12.07 mm on average), it can only be confused with Sp. pusio Smetana, 2005 and Sp. radani Smetana, 2016 . However, it can be easily distinguished from these two species by the presence of dense yellowish-golden tomentose pubescence on the tergites 6–8 sometimes even covering tergites 6–7.

Sphaerobulbus miwai is the only member of this genus in Taiwan. It can be distinguished from almost all other Staphylinina by the single simple tooth on each mandible. This character is shared with the genus Apecholinus but in Taiwan, Sp. miwai can be distinguished by the elytra markedly shorter than pronotum and the much smaller size.

Bionomics. Based on an import of locality name into Google Earth from collection data ( Bernhauer 1943 and this study), the species occurs from 2113–3350 m. Apparently, this species only occurs on high mountains. Some specimens of Sp. miwai were collected by pitfall traps set in Abies forest (as in photos 8 and 9 in Smetana 1995: p.13). The specimens from Tian Pond were collected from under stones on a grassland near the trail. The specimen from Tefuye Historic Trail was collected from under a stone near a creek. The specimen from Meifeng was collected by sifting leaf litters in forest.

Distribution. Sphaerobulbus miwai is restricted to high elevation mountainous areas in central and southern Taiwan including Chiayi County, Nantou County and Taichung City. The reduced hindwings suggest that Sp. miwai is an endemic species to the island with distribution restricted to the high mountainous areas of central and southern Taiwan.

Remarks. Bernhauer (1943) described Staphylinus (Xanthocypus) miwai based on two specimens from Taiwan. Herein, I re-examined the type series of this species and discovered that its morphology fits the generic definition of the genus Sphaerobulbus Smetana, 2003 based on the presence of only one simple tooth on the medial margin of each mandible and remarkably spherical bulbus of the aedeagus. Hence, I move this species to the genus Sphaerobulbus .

Figures

FIGURES 8–13. 8. Miobdelus humilis sp. nov.: male, paratype. 9. Miobdelus taiwanensis taiwanensis: male. 10. Nelmanwasus ornatus: male. 11–12. Sphaerobulbus miwai comb. nov.: male, lectotype of Staphylinus (Xanthocypus) miwai and attached labels; male. 13. Naddia taiwanensis: female. Scale bar: 3 mm

FIGURES 28–34. Sphaerobulbus miwai comb. nov. 28. Aedeagus in ventral view; 29. Aedeagus in lateral view; 30. Apical portion of underside of paramere with sensory peg setae; 31. Sternite 8, male; 32. Sternite 9, male; 33. Tergite 10, male; 34. Tergite 10, female. Scale bar: 0.5 mm

FIGURES 50–53. Live specimens of Staphylinina in Taiwan: 50. Agelosus auricomus (Photo by J.-M. Chen); 51. Miobdelus humilis sp. nov., paratype (Photo by K.-W. Chan); 52. Sphaerobulbus miwai comb. nov.; 53. Thoracostrongylus formosanus.