Oiceoptoma tangi Sommer, Ruzicka, Nishikawa & Schneider 2021, new species
Creators: name: Sommer, David
name: Růžička, Jan
name: Nishikawa, Masaaki
name: Schneider, Jan
Publisher: name: Zenodo
Year: 2021
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Insecta
Coleoptera
Silphidae
Oiceoptoma
Oiceoptoma tangi

description: Oiceoptoma tangi Sommer, Růžička, Nishikawa & Schneider, new species
(Figs. 1A–F, 3D–F, 4A, D, 5A, D, 6A, D, 7A–C, 8A, C–D, 9A–B, 10A–D, 11A–B, 12A, D, 13A–B, 14 C–E, 15A–B, F, 17A–C)
Oiceoptoma subrufum: Růžička et al. 2004: 47 (misidentification).
Type locality. China, Zhejiang Province, Anji City, Longwangshan Mt., Pinxi Creek, 30°24′N, 119°27′E, alt. 1000– 1100 m.
Type material (30 specimens). Holotype, ♂ (SNUC), “ China: Zhejiang Prov. | Anji City | Longwangshan Mt. | Pinxi Creek | 30°24′N, 119°27′E || alt. 1000~ 1100 m | 09-VI-2012 | HU & YIN leg. [p]”. Paratypes, 6 ♂♂ 3 ♀♀ (SNUC), 1 ♂ 1 ♀ (BMNH), 2 ♂♂ 2 ♀♀ (JRUC), same data as holotype ”; 2 ♂♂ 3 ♀♀ (SNUC), “ China, Zhejiang Prov. | Anji County | Shenxi | 30° 25′ N, 119° 24′ E | alt. 400 m, 07-VI-2012 | ZHU Jian-Qing leg. [p]”; 1 ♀ (EUMJ), “中国 [= China] 浙江省 [= Zhejiang Prov.] OiṘ市 [= Lin’an-shi] | MRH山 [= Mt. West Tianmu Shan] | 6~ 11–V–1998 | 李 李ù [= Li-Zhen Li] IJDz [= leg.] [p]”; 1 ♀ (SNUC), “16~20–V–20 [p] 06 [hw] | MRH山 [= Mt. West Tianmu Shan] 临Ṙ [= Lin’an-shi] [hw] | 浙江 [= Zhejiang Prov.] Bwx [hw] || Mt. w. Tianmu | 16~20. V, 2006 | Bi Wen-xuan leg. [hw]”; 1 ♂ (SNUC), “ West Tianmushan | Lin’an County | 11~ 15–VI–2006 | alt. 300–400 m | HU & TANG leg. [p]”; 1 ♀ (SNUC), “ China: Zejiang Prov. | Lin’an City | Mt. West Tianmu | alt. 300~ 500 m | 29–V~ 3–VI–2010 | Jian-Qing ZHU leg. [p]”; 1 ♂ (JRUC, DNA voucher JRUC-SIL-0054), “ CHINA: Zhejiang Prov., | Lin’an County, West | Tianmushan Nat. Res., | 250 m NW of Original | Temple of Lion Sect, | 30.3431°N 119.4316°E, | J. Hájek & J. Růžička leg. || (WT10) 2.–6.vii.2017; || 1165 m, baited pitfall | traps #06 (fish meat, | ripening cheese), broad- | leaved deciduous forest | with Rhododendron [p]”; 2 ♀♀ (JRUC, DNA vouchers JRUC-SIL- 0010, JRUC-SIL-0011), “ CHINA: Zhejiang Prov., | Lin’an County, West | Tianmushan Nat. Res., | 250 m NW of Original | Temple of Lion Sect, | 30.3431°N 119.4316°E, | Cheng-Bin Wang leg. || (WT10) 2.–6.vii.2017; || 1165 m, baited pitfall | traps #06 (fish meat; alcohol, vinegar + sugar), broad- | leaved deciduous forest | with Rhododendron [p]”; 2 ♂♂ (JSCC), “NW. CHINA | TIENMUCHAN [without date and collector’s name, hw with a pencil] || Oiceoptoma | subrufum | (Lewis, 1888) ♂ | Jan Růžička det. 200[p]3[hw]”.
Description. Male (Figs. 1A–C). Body oval, dorso-ventrally flattened. Pronotum orange with four black spots (Fig. 4A). Elytra light to dark brown. Head, antennae, legs and ventral part of body black. Flight wings fully developed, functional (Fig. 8A).
Head. Black, lustrous surface with regular punctation (Fig. 3D). Covered with short, recumbent orange setation. Clypeus anteriorly widely notched (Fig. 8D). Anterior margin of clypeus with slightly irregular row of dense, long, orange setation in dorsal view. Eye kidney-shaped in lateral view (Fig. 17C). Head with short row of long erect setae behind eyes (Fig. 3D). Frons with marked dorsal tentorial pits and a transverse, elevated crest posteriorly (Figs. 3D, 17C). Maxilla with deeply punctuated cardo and base of stipes in ventral view, covered by long setae (Fig. 3E).
Antennae. Medium-sized, with last four antennomeres forming a distinct club (Figs. 7A–C).
Pronotum moderately transverse, widest posteriorly (Fig. 4A). Pronotal disc orange, medially with four black, vaguely delimited spots, arranged in symmetrical, trapezoidal pattern (Fig. 4A). Spots are regularly covered with fine, distinct punctures, bearing long, orange setation (Fig. 4D). Margin rimmed only in anterior half; anteriorly with wide, shallow excision, which is medially straight; anterior angles weakly elevated. Posterior margin slightly sinuous, weakly sinuate postero-laterally (Figs. 4A, 6A). Surface with dense punctation, punctures medium-sized, clearly separated, from disc to margin deeply impressed (Figs. 4A, 5D). Pronotum covered with longer, orange setation.
Scutellum. Irregularly triangular, widely vaulted medially. Surface with dense, distinct, homogenous punctation; covered with longer orange setation, semierect anteriorly and distinctly recumbent medially and posteriorly (Fig. 6A).
Elytra subparallel, at the widest point (along 2/3 of its length) wider than pronotum (Fig. 1A). Humerus with distinct denticle (Fig. 3F). Elytron with three distinctly elevated ridges; only first and second ridge reaching apex of elytron; external ridge shortest, reaching only two thirds of elytral length (Figs. 1A, 6D, 9A). Second ridge in last third slightly sinuous (Fig. 9A). Third ridge posteriorly terminated at apical callus (Fig. 9A). Ridges on both sides covered with a row of short, recumbent, black setae. Lateral margin of elytra strongly elevated only in anterior half, disappearing posteriorly. Apex of elytron regularly rounded (Figs. 1A, 9A). Basal part of elytra and humeri with short, recumbent, black setae (Fig. 3F). Surface dull, with isodiametric microsculpture (Figs. 6A, D); subapical surface regularly flat, without rugosities; with dense, distinct, regular punctation; punctures clearly separated by spaces 1.0–1.5 times their own diameter (Figs. 6D, 9A). Elytra with distinct, subrectangular punctures, with bluish metallic lustre covering most of the surface in ventral view (Figs. 8A, C). Elytral epipleura sparsely, finely but distinctly punctured in ventral view (Fig. 8A).
Ventrum finely punctate, covered with short, recumbent, brown to black setation (Figs. 5A, 10C). Proventrite with dense punctation laterally; medially dark brown to black, laterally widely orange in ventral view (Fig. 5A). Mesocoxae widely separated (Fig. 10C). Abdominal ventrites with distinct impressions laterally in ventral view (Figs. 1B, 15A). Ventrite 6 extremely reduced in length medially, with expanded brick-wall pattern on intersegmental membrane (Figs. 15A–B, F).
Legs. Protarsomeres 1–4 only slightly expanded, covered with short, dense, yellow setation (Figs. 14C–D). Pro-, / meso- and metatibia with two apical spurs of different length (Figs. 14C–D). Metatibia almost straight, only very slightly curved in ventral view (Fig. 10D).
Abdominal segments. Tergite 10 relatively short in length (Fig. 12A). Ventrite 9 oval, elongate, anteriorly as long as tergite 9, constricted and deeply desclerotized medially in ventral view (Fig. 12D). Spiculum gastrale robust, elongate in ventral view (Fig. 12D).
Aedeagus. Median lobe stout, robust, gradually tapered to widely rounded, triangular apex (Figs. 11A–B). Internal sac heavily sclerotized, medial portion composed of a great number of very small, regular, rounded denticles; basal part containing two strips of elongate, slender denticles (Fig. 11B). Parameres robust, almost straight, longer than median lobe, subapically constricted with rounded apex (Figs. 11A–B). Basal portion widely oval, very narrow, markedly exceeding the width of aedeagus (Figs. 11A–B).
Sexual dimorphism. Female. Similar to male except for the following structures: Protarsus simple, basal protarsomere elongated (Fig. 14E). Apex of elytron elongated to a blunt tip (Figs. 1D–E, 8A, 9B). Tergum 7 with distinct, deep, narrow, U-shaped medial emargination (Fig. 17A). Tergum 8 subquadrate, regularly rounded posteriorly (Figs. 13A, 17A). Ventrite 8 widely transverse (Figs. 13B, 17B). Tergite 9 elongate, rounded; tergite 10 pentagonal, apex posteriorly regularly rounded with dense microsetae (Figs. 10A–B, 13A). Coxite laterally constricted on outer margin subapically in ventral view; stylus inserted lateroapically, its length slightly shorter than apex of coxite (Figs. 10A–B, 13A–B).
Measurements. Elytra length 5.81–6.82 mm in males (mean 6.30 mm; 6.27 mm in the holotype), 6.72–7.26 mm (mean 6.96 mm) in females; pronotum length 3.41–3.82 mm in males (mean 3.63 mm; 3.55 mm in the holotype), 3.50–3.81 mm (mean 3.62 mm) in females; pronotum width 5.62–6.66 mm in males (mean 6.07 mm; 5.92 mm in the holotype), 5.63–6.42 mm (mean 6.10 mm) in females.
Variability. Elytra mostly dark brown, light brown in some (probably subteneral) specimens. Spots on pronotum slightly differently delimited, being less separated from surrounding surface in some specimens.
Differential diagnosis. Oiceoptoma tangi Sommer, Růžička, Nishikawa & Schneider, new species, is similar and probably closely related to O. nigropunctatum and O. subrufum. All three species share the following combination of characters: (1) orange pronotum with relatively short pubescence; (2) four dark spots on pronotal disc; (3) dark brown/black elytra with narrow epipleura; and (4) absence of patchy velvet pattern on elytral dorsal surface (see Růžička et al. (2004) for more details).
The three species can be separated from each other using the character states listed in the modified key and in Table 1 below.
Etymology. Patronymic, named after Liang Tang (Shanghai, China), an enthusiastic specialist of staphylinoid beetles (Agyrtidae, Staphylinidae: Steninae, Scaphidiinae, Staphylininae, Omaliinae etc.), who first recognized this species was unnamed.
Collecting circumstances. The large type series was collected near Pinxi Creek on old large mammal carrion, together with numerous Necrodes littoralis (Linnaeus, 1758) (Silphidae), Creophilus maxillosus (Linnaeus, 1758) (Staphylinidae) and some clown beetles (Histeridae) (Figs. 18A–C). Three specimens were also collected on West Tianmushan, 250 m above the Original Temple of Lion Sect, using fish-baited pitfall traps in a broadleaved deciduous forest with Rhododendron (Figs. 19A–B). The specimens were collected between May and the beginning of July.
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Distribution. So far known only from three localities (Longwangshan Mt., Shenxi, Tianmu Shan Mts.) in Zhejiang Province, China (Figs. 20–21).
description: Published as part of Sommer, David, Růžička, Jan, Nishikawa, Masaaki & Schneider, Jan, 2021, Oiceoptoma tangi (Coleoptera: Silphidae: Silphinae), a new species of carrion beetle from eastern China, pp. 445-472 in Zootaxa 4949 (3) on pages 466-469, DOI: 10.11646/zootaxa.4949.3.2, http://zenodo.org/record/4640397