Anthobium morosum, Shavrin, 2022

Shavrin, Alexey V., 2022, A revision of Palaearctic Anthobium Leach, 1819 (Coleoptera: Staphylinidae Omaliinae: Anthophagini). V. Algidum, morosum and tectum groups, a new species of the fusculum group, and faunistic records, Zootaxa 5104 (3), pp. 301-346 : 310-314

Anthobium morosum sp. n.

( Figs. 26–28 , 29–45 , 93 )

Type material examined: Holotype ♂ [dissected]: ‘ NEPAL (Prov. Bagmati) | Malemchi [Melamchi], 2800 m | 16.IV. [19]81 | [I.] Löbl & [A.] Smetana’ <printed>, ‘HOLOTYPE | Anthobium | morosum sp. n. | Shavrin A.V. des. 2022’ <red, printed> ( CNN).

Paratypes (2 specimens): 2 ♀♀ [one specimen dissected]: same data as the holotype (cSh, CNN). All paratypes with additional red printed label: ‘ PARATYPE | Anthobium | morosum sp. n. | Shavrin A.V. des. 2022’.

Description. Measurements (n=3): HL: 0.66–0.70; HW: 1.00–1.05; AL (holotype): 2.20; OL: 0.27–0.30; PL: 0.90–0.95; PW: 1.50–1.60; ESL: 2.20–2.30; EW: 2.01–2.09; AW: 1.65–1.85; MTbL (holotype): 1.45, MTrL: 0.60 (MTrL 1–4: 0.37; MTrL 5: 0.23); AedL: 1.46; TL: 5.65(holotype)–5.80.

Body moderately large, elongate, convex ( Fig. 26 ). Body brown; antennomeres 3–11, lateral and apical margins of scutellum, lateral margins of pronotum and legs yellow-brown; mouthparts, antennomeres 1–2 and apical tarsomeres yellow. Forebody glossy, with rudiments of indistinct striate microsculpture in middle of head (one paratype); posterio-lateral parts of head and portion between antennal insertion and anterior margin of eye, and abdominal tergites with distinct isodiametric microsculpture. Head and neck with sparse, irregular and moderately deep punctation, sparser between anteocellar foveae and margins of eye, with impunctate longitudinal portions of inner margins of median impression; middle of pronotum with irregular punctation, slightly denser than that on head, distinctly sparser in latero-apical portions, with narrow impunctate portions behind lateral pits; scutellum with several moderately large and deep punctures; punctation of elytra denser and coarser than that on pronotum, each elytron with tangled and vague seven to eight longitudinal rows of serial punctures, apical portion of each elytron finer and sparser; abdominal tergites IV–VI without visible punctures, apical part of abdominal tergite VII and tergite VIII with fine and irregular punctation. Apical and middle parts of head, middle of pronotum and elytra, paratergites and abdominal tergites with very fine and sparse, semierect pubescence; abdominal tergites with additional very short and sparse setae, denser on apical margins.

Head 1.5 times as broad as long, with slightly convex middle portion; middle portion with wide and moderately deep semicircular impression; anteocellar foveae narrow, diagonally directed toward about level of anterior margins of eye or slightly shorter; postocular ridges distinct, smooth; anterior portion between antennal insertion and anterior margin of eye widely concave. Ocelli large, situated at level of postocular ridge, distance between ocelli distinctly longer than distance between ocellus and posterior margin of eye. Eyes large, convex. Gular sutures with rounded apical parts, widely divergent posteriad; distance between sutures moderately narrow, shortest distance located at level about posterior margins of eyes ( Fig. 34 ). Labrum transverse, with widely rounded and strongly protruded apicad membranous latero-apical portions, with wide and very deep apical emargination, and long laterobasal projections (internally, under the clypeus) ( Fig. 29 ). Mandibles long, distinctly asymmetric, with narrow basal part and elongate, moderately narrow and strongly curved apical portions (larger and more curved in lefte mandible), with large subtriangular tooth below middle of right mandible, with apex slightly protruded apicad; molar lobes moderately small and narrow ( Fig. 30 ). Labium moderately narrow, with apical labial palpomere about four times as long as preceding segment ( Fig. 32 ). Mentum narrow, strongly transverse, with two pairs of long latero-apical setae ( Fig. 33 ). Maxilla as in Fig. 31 ; maxillary palpomere long, with elongate maxillary palpomere 2, slightly shorter than apical palpomere, and apical palpomere very long, slightly more than three times as long as preapical segment, narrow in basal portion, gradually broadened toward apical third, with rounded apex; galea moderately wide, distinctly longer than lacinia; lacinia with narrow and curved apical portion, with unarticulated spine-like apex and numerous spines and setae along medial margin. Antennae moderately long, with elongate antennomeres, reaching basal third of elytra when reclined; basal antennomere long, about three times as broad as long, antennomere 2 slightly narrower and 1.3 times as long as basal antennomere, 3 distinctly longer and slightly narrower than 2, 4–6 distinctly shorter than 3, 7 slightly longer and broader than 6, 8–9 slightly shorter than 7, 10 slightly shorter and broader than 7, apical antennomere broader and 1.4 times as long as preceding segment, from apical third sharply narrowed toward subacute apex.

Pronotum transverse, 1.6 times as broad as long, 1.5–1.6 times as broad as head, widest about middle, distinctly more narrowed posteriad than anteriad, with widely rounded and slightly protruded apical angles; posterior angles obtuse, with slightly concave latero-basal margins; apical margin widely rounded, distinctly shorter than moderately straight or rounded posterior margin; middle portion evenly elevated, with or without indistinct longitudinal and distinct, wide semicircular impression in mediobasal third; lateral edges with distinct, irregular, small crenulation; lateral portions slightly explanate and widely impressed, each with deep oval pit slightly in front of middle. Prothorax with moderately long and narrow interocoxal process and widely protruded mesosternal processes ( Fig. 35 ). Mesoventrite moderately narrow, with acute intercoxal process, reaching apex of posterior margin of procoxae ( Fig. 38 ). Scutellum large, with widely rounded apical portion ( Fig. 36 ). Metaventrite with very wide and deep intercoxal cavities and wide intercoxal process with rounded apex ( Fig. 39 ). Metendosternite as in Fig. 40 .

Elytra slightly longer than broad and slightly broadened posteriad, reaching apical margin of abdominal tergite IV, with widely rounded apical margins, distinctly more than twice as long as pronotum; humeri widely rounded, not protruded anteriad ( Fig. 37 ); middle surface of each elytron with two indistinct longitudinal elevations; lateral portions narrow, slightly explanate; latero-apical edges with small and acute crenulation, more flattened and reduced in about apical third. Hind wings fully developed.

Legs long and slender, with very dense and long setation on pro- and mesotibiae, with additional long and moderately dense setae on inner sides, setation of metatibiae somewhat finer and sparser, with several stout setae around apical margin of each mesotibiae; middle and apical portions of inner sides of pro- and mesotibiae with two long rows of short peg-setae; pro- and mesotarsi twice longer than tibiae, metatarsi two and a half times as long as metatibia; apical metatarsomere of all tarsi about as long as three preceding combined tarsomeres.

Abdomen convex, distinctly narrower than elytra, with a pair of small and oval tomentose spots in middle of tergire V, with narrow palisade fringe on margin of abdominal tergite VII; intersegmental membranes between tergites IV–VI with brickwall-like sculpture; tergites and sternites VIII elongate ( Figs. 41–42, 44–45 ).

Male. Protarsomeres 1–4 wide. Apical margins of abdominal tergite VIII ( Fig. 41 ) and sternite VIII ( Fig. 42 ) slightly sinuate. Aedeagus narrow and very long, with small basal bulb, gradually narrowed toward median lobe with widely rounded apex; parameres very long, significantly exceeding apex of median lobe, significantly broadened in preapical portion and strongly narrowed toward slightly curved apices; each paramere with three short latero-apical setae; internal sac very narrow, long ( Fig. 27 ). Lateral aspect of aedeagus as in Fig. 28 .

Female. Protarsomeres 1–4 moderately narrow. Apical margin of abdominal tergite VIII straight ( Fig. 43 ). Apical margin of abdominal sternite VIII ( Fig. 44 ) rounded. Genital segment with elongate sternite IX, gonocoxites moderately narrow and long, subparallel-sided, styli elongate and narrow, each with long seta ( Fig. 45 ).

Distribution. The new species is at present known only from the type locality in central Nepal ( Fig. 93 ).

Natural history. The specimens were collected at an elevation 2800 m a.s.l. Detailed ecological data are unknown.

Etymology. The specific epithet (Latin adjective: strange) alludes to the unusual shapes of some morphological structures of the body.

Figures

FIGURE 93. Distribution of Anthobium in China and Nepal: A. cornatipenis (black circle), A. himalayense (black star), A. infractum (white square), A. morosum (white star), A. multipunctatum (white circle), A. smetanai (black square), A. umbrinum (black triangle), A. vitreum (black diamond).

FIGURES 26–28. Habitus (Fig. 26; paratype) and aedeagus (Figs. 27—28) of Anthobium morosum: 27—parameral view, 28—lateral view. Scale bar: 1.0 mm (Fig. 26), 0.1 mm (Figs. 27–28).

FIGURES 29–33. Mouthparts (dorsal view) of Anthobium morosum: 29—labrum, 30—mandibles (left and right), 31—maxilla (left), 32—labium, 33—mentum. Scale bar: 0.1 mm.

FIGURES 34–45. Anthobium morosum: 34—ventral aspect of head (ventral view), 35—ventral aspect of prothorax (ventral view), 36—scutellum (dorsal view), 37—ventral aspect of elytron, 38—ventral aspect of mesoventrite, 39—ventral aspect of metaventrite (without metanepisternum), 40—metendosternite (ventral view), 41—male abdominal tergite VIII (dorsal view), 42—male abdominal sternite VIII (ventral view), 43—female abdominal tergite VIII (dorsal view), 44—female abdominal sternite VIII (ventral view), 45—female genital segment (ventral view). Scale bar: 0.1 mm.