Agelosus auricomus, Smetana & Hu, 2019

Smetana, Aleš & Hu, Fang-Shuo, 2019, The genera Agelosus Sharp, 1889 and Apecholinus Bernhauer, 1933 in Taiwan (Coleoptera: Staphylinidae: Staphylinini: Staphylinina), Zootaxa 4638 (3), pp. 379-388 : 380-381

Agelosus auricomus sp. nov.

( Figs 1–5 , 19, 23 , 26 )

Type locality. TAIWAN: Taipei City .

Type material. Holotype, male “ 28-V-2016 ♂ TAIWAN: Taipei City , oldTianmu Trail [in Chinese] Y. H. Ho leg.” (In NMNS) . Allotype, female: “ 30-V-2015 TAIWAN. Taipei City, Jinshan village B.H. Ho leg.” ( FSHC) . Paratypes: “ 02-V-218 ♂ TAIWAN: Taipei City , Fuyang S.W. Zhang leg., 1 ♂ ( FSHC) ; “ 09-VI-2016 TAIWAN: Taipei City , Shanzhuhu B.H. Ho leg., 1 ♂ ( CNC) ; “ 26-V-2018 TAIWAN: New Taipei City, Xindian District , Nankan Mt . S.P. Lin leg. By hand collecting / Fang-Shuo collection”, 1 ♂ ( FSHC) ; “ TAIWAN: Taipei City , Erzihping Trail , Erziping Trail [in Chinese], Beitou. 17.VI.2016. leg. Y.H. Ho / Fang-Shuo collection”, 1♀ ( FSHC) ; “ 04-III-2018 TAIWAN: Yilan County, Jiaoxi Township , Linwei Road [in Chinese], F.S. Hu leg. / 24 49’14.4”N 121 43’17.2”E (alt. 510 m)”, 1 ♀ ( CNC) .

Diagnosis. Species similar to A. nigricollis Smetana, 2018 , but with golden yellow tomentose pubescence on the head limited to middle portion and present also on the neck.

Description. Black, head with golden yellow tomentose pubescence on middle portion, rest of head with black pubescence; neck with golden yellow tomentose pubescence; pronotum with uniform black pubescence; each elytron with black pubescence and with more or less triangular patch of golden-yellow tomentose pubescence below humerus; abdomen with black pubescence, but tergites 6 to 8 each with a basal pair of spots of golden yellow tomentose pubescence, those on tergite 8 small; maxillary and labial palpi brunneous to piceous; antennae piceous-black to black, first three segments more or less paler; legs variably brunneous. Head of rounded quadrangular shape with rounded posterior angles, wider than long (ratio 1.20), eyes small, moderately convex, slightly shifted dorsad, tempora longer than length of eyes seen from above (ratio 1.38); disc of head moderately finely and densely punctate, punctation becoming gradually finer and denser posteriad and posteriolaterad; linear impunctate midline present; interspaces between punctures without microsculpture. Antennae moderately long, hardly thickened toward apex, segment 3 longer than segment 2 (ratio 1.23), segments 4–9 longer than wide, gradually becoming shorter, segment 10 as long as wide, last segment small, asymmetrically emarginated, along lateral margin shorter than penultimate segment. Pronotum about as long as wide, moderately convex, narrow marginal groove disappearing downwards at about anterior third of pronotal length; punctation on disc about the same as that on disc of head, interspaces between punctures without microsculpture; quite fine impunctate line present mostly on posterior half of pronotum. Prescutum moderately densely punctate-setose, interspaces with distinct microsculpture of transverse and oblique striae. Scutellum densely punctate/setose, with granulose microsculpture. Elytra moderately long, hardly dilated posteriad, at suture shorter than pronotum at midline (ratio 0.78), at sides vaguely longer than pronotum at midline (ratio 1.08); punctation very fine and very dense, interspaces between punctures with fine microscopic irregularities, elytra therefore appearing slightly dull. Wings folded under the elytra, but probably non-functional. Abdomen with fifth visible tergite with pale apical seam of palisade setae; tergite 2 (in front of first fully visible tergite) with a row of punctures along apical margin, surface with extremely fine, superficial microsculpture of oblique striae; punctation of all tergites markedly finer and denser than that on elytra, punctation becoming gradually somewhat sparser toward apex of abdomen, interspaces with extremely fine, granulose microsculpture.

Male. Sternite 8 with very shallow, inconspicuous, obtuse medioapical emargination. Genital segment with tergite 10 narrow, markedly, evenly narrowed toward subacute apex, apical portion with numerous long, densely set setae, rest of tergite rather densely setose, as in Fig. 1 ; sternite 9 with narrow basal portion, apical portion with deep and wide medioapical emargination, setose as in Fig. 2 . Aedoeagus (Figs 3,4) rather small, median lobe short, parallel-sided, with widely, asymmetrically, arcuate apex; paramere narrow, situated on median lobe quite asymmetrically toward left margin of median lobe, with subacute apex not quite reaching apex of median lobe; with several, minute apical setae on medial margin; underside without sensory peg setae ( Fig.4 ).

Female. Tergite 10 of genital segment wide, markedly narrowed toward slightly differentiated, narrow apical portion with narrowly arcuate apex, with numerous, moderately long to very long and strong setae on differentiated portion, rest of tergite setose as in Fig. 5 .

Length 18.0–23.0 mm.

Geographical distribution. The species is at present known from several locations within Taipei City and from Yilan county, both in northern Taiwan.

Bionomics. Little is known about the habitat requirement of this species. It seems to occur at lower elevations (one specimen was taken at an elevation of 510 m). The specimen from Ilan, collected by the second author, was taken from under a stone in a valley in a mixed wood forest ( Fig. 26 ).

Etymology. The specific epithet is a composition of the Latin adverb aureus, -a, - um (golden) and the noun coma, - ae, f (the hair). It refers to the golden-yellow tomentose spots on the body of the species.

Comments. The aedoeagus of the holotype lacks the apical portion.

Agelosus auricomus sp. nov., A. weisei ( Harold, 1877) and A. nigricollis Smetana, 2018 , the latter two from Japan, mainland China, and North and South Korea, share the character state of the paramere of the aedoeagus lacking any sensory peg setae. They apparently form a clade within the genus.

Figures

FIGURES 1–7. 1–5. Agelosus auricomus: 1, tergite 10 of male genital segment; 2, sternite 9 of male genital segment; 3, aedoeagus, parameral view; 4, apical portion of paramere; 5, tergite 10 of female genital segment. 6–7. Apecholinus fraternus: 6, tergite 10 of male genital segment; 7, sternite 9 of male genital segment.

FIGURES 19–24. 19: Agelosus auricomus: holotype, length 21 mm. 20: Apecholinus fraternus, length 20.0 mm. 21: Apecholinus imitator, holotype, length 22.0 mm. 22: Apecholinus canifer: paratype, length 20.0 mm. 23: Agelosus auricomus, right mandible. 24: Apecholinus fraternus, left mandible.

FIGURES 25, 26.: Live specimen of Apecholinus imitator (photo by R.-H. Liu). 26: habitat of Agelosus auricomus (photo by Hu).