Mannerheimia Mäklin, 1880

Shavrin, Alexey V., 2021, On the genus Mannerheimia Mäklin, 1880 (Coleoptera: Staphylinidae: Omaliinae: Anthophagini), with taxonomic and faunistic notes on some species, Zootaxa 5040 (3), pp. 301-333 : 303-305

Mannerheimia Mäklin, 1880

( Figs. 1–9 , 12–38 )

Type species: Omalium divergens Mäklin, 1878

Mannerheimia Mäklin, 1880a: 80 ; Mäklin, 1880b: 39, Ganglbauer 1895: 725, Luze 1905: 251, Porta 1926: 24, Cameron 1930: 149, Palm 1948: 94, Zanetti 1987: 273, Watanabe 1990: 77

Redescription. Body moderately wide ( Figs. 1, 5–9 ) or elongate ( Figs. 2, 4 ), slightly or strongly convex, shiny; length 1.90–4.24 mm. Coloration varying from yellow-brown to dark-brown, sometimes with paler pronotum and/ or elytra. Forebody with fine to coarse, dense to sparse punctation; punctation of abdomen fine or missing. Head and pronotum with fine to coarse microreticulation or without it; abdomen usually with distinct isodiametric microsculpture. Body glabrous, with sparse small setae on frontal portion of head and sometimes on pronotum and elytra or densely covered by short or moderately long setation ( M. asiatica ); abdominal tergites with or without very fine, sparse setae.

Head transverse, with slightly elevated supra-antennal prominences and middle portion; anteocellar foveae missing or present, short or elongate; mediobasal portion without longitudinal impression; postocular ridges missing, temples short, gradually narrowed toward neck or moderately long ( M. asiatica ). Ocelli small, sometimes indistinct, or large and convex. Eyes convex, large or moderately small ( M. asiatica ). Gular sutures widely separated at about level of posterior margins of eyes, slightly divergent posteriorly towards base of head ( Fig. 26 ). Labrum transverse, with widely rounded latero-apical portions, wide apical emargination and moderately long laterobasal projection ( Fig. 12 ). Mandibles wide and subtriangular, each with moderately narrow and elongate apical portion, wide and large prostheca and molar area, with distinct subtriangular tooth in middle of right mandible ( Fig. 13 ). Mentum small, with two long latero-apical setae; labium wide, with short preapical labial palpomere, about as long as broad or distinctly transverse, apical palpomere, more than twice as long and about as broad as preceeding segment ( Fig. 15 ). Maxilla as in Fig. 14 ; preapical segment of maxillary palpus long, more than twice as long as, and slightly broader than preceding segment. Antenna short, reaching posterior margin of pronotum or apical third of elytra when reclined, with transverse ( Figs. 18–19 ) or elongate ( M. arctica , Figs. 16–17 ) antennomeres 4–10.

Pronotum transverse ( Figs. 20–25 ), widely rounded toward latero-apical portions, sometimes slightly protruded anteriad, and slightly or distinctly narrowed toward obtuse or widely rounded posterior angles, with or without laterobasal impressions; lateral portions narrow, slightly explanate. Prothorax with elongate, narrow intercoxal process and strongly protruded, long prosternal processes ( Fig. 27 ). Mesoventrite transverse, with long intercoxal process, reaching about middle of mesocoxae ( Fig. 28 ). Scutellum wide, with rounded apex ( Fig. 31 ). Metaventrite with wide and deep intercoxal cavities and moderately short, subtriangular intercoxal process, almost reaching mesosternal process ( Fig. 29 ).

Elytra short or moderately long, gradually or strongly widened apicad ( Fig. 32 ); lateral portions narrowly flattened, with bordered margins. Wings fully developed or reduced ( M. asiatica , M. pleshanovi sp. n.).

Legs long and slender; tibiae covered with moderately sparse and long setae, these setae stouter on meso- and metatibiae; metatarsus about twice as long as metatibia ( Fig. 33 ); apical metatarsomere about twice as long as two preceding tarsomeres together.

Abdomen convex, short or strongly extended, with or without two transverse wing-folding spots in middle of tergite V, with narrow palisade fringe on apical margin of tergite VII in winged species, without palisade fringe in wingless species.

Male. First four protarsomeres widened. Aedeagus suboval or elongate, with narrow or widely rounded apex; parameres slightly or distinctly exceeding apex of median lobe or shorter, slightly or significantly widened apically; middle portion of median lobe with distinct transverse sclerotized structure ( Figs. 42, 47 , 48, 50 , 57, 59 ); internal sac long, narrow or wide, usually with two long fields of elongate thorns ( Figs. 42–43 , 48 , 57, 61 , 66 , 70 ).

Female. First four protarsomeres narrow. Genital segment with narrow short sternite IX, wide and long gonocoxites, and with narrow, elongate styli, each with a very long apical seta ( Fig. 38 ).

Differential diagnosis. Regarding the shape of the smaller and less pubescent antennomere 5 and the general shape of the aedeagus, Mannerheimia is similar to the monotypic genus Phyllodrepoidea Ganglbauer, 1895 . It differs from Phyllodrepoidea by a less regular arrangement of the elytral punctation and narrower apical portions of the parameres. Based on the general shape of the body, these two genera are somewhat similar to species of the Anthobium group of genera (e.g. Shavrin & Smetana 2017, 2020), from which they can be distinguished by the absence of postocular ridges on the head and lateral pits on the pronotum, greater distance between the gular sutures, and broader gonocoxites.

Bionomics. For most species of Mannerheimia ecological data are unknown. Members of the genus may be regarded as hygromesophilous. They inhabit mixed forests from low to high elevations and can be found in wet habitats such as mosses, litter, soil, various debris, etc.; some species have been found near snowfields and glaciers.

Figures

FIGURES 1–9. Habitus of Mannerheimia: 1—M. afghanica (paratype), 2—M. arctica, 3—M. asiatica, 4—M. brevipennis, 5—M. japonica, 6—M. obscura, 7—M. pleshanovi (paratype), 8—M. yasudai, 9—M. zanettii (paratype). Scale bar: 1.0 mm.

FIGURES 12–15. Mouthparts of Mannerheimia arctica: 12—labrum (dorsal view), 13—mandibles (left and right, dorsal view), 14—maxilla (left, dorsal view), 15—labium and mentum (ventral view). Scale bar: 0.1 mm.

FIGURES 16–25. Antenna (Figs. 16–19) and pronotum (Figs. 20–25) of Mannerheimia arctica (Figs. 16–17, 20–22), M. brevipennis (Figs. 18–19, 23–24) and M. pleshanovi (Fig. 25): 16, 18—right antenna of male, 17, 19—right antenna of female, 20—Irkutsk Area: Vitimskiy Nature Reserve, 21—Krasnoyarsk Territory: Potapovo, 22—Murmansk Area: Khibiny, 23—Krasnoyarsk Territory: Lebyazhya River, 24—China (Xinjiang), 25—Irkutsk Area: Khamar-Daban (paratype). Scale bar: 0.1 mm.

FIGURES 26–38. Body parts of Mannerheimia arctica: 26—ventral aspect of head, 27—ventral aspect of prothorax, 28—ventral aspect of mesoventrite, 29—ventral aspect of metaventrite (without metanepisternum), 30—metendosternite (ventral view), 31—scutellum (without lateral structures, dorsal view), 32—ventral aspect of elytron, 33—hind tibia and tarsus (anterior view), 34—male tergite VIII (dorsal view), 35—male sternite VIII (ventral view), 36—female tergite VIII (dorsal view), 37—female sternite VIII (ventral view), 38—female genital segment (dorsal view). Scale bar: 0.1 mm.

FIGURES 42–47. Aedeagus of Mannerheimia arctica (42: Buryatia: Gitara Lake, 43–44: Murmansk Area: Khibiny, 45: Tymen Area: Sob` St., 46: Yamal: Shchuchye, 47: Kemerovo Area: Belogorsk): 42–43, 45–47—parameral view, 44—lateral view. Scale bar: 0.1 mm.

FIGURES 48–56.Aedeagus of Mannerheimia brevipennis (48–49: Kazakhstan:Aksu, 50: Krasnoyarsk Territory:Turukhanskiy District, 51: Buryatia: Okinskiy District, 52: Yamal: Sopkey; 53: Kyrgyzstan:Ala Too; 54: Yakutia: Spasskiy; 55: Iran: Esfahan; 56: China: Xinjiang): 48, 50–56—parameral view, 49—lateral view. Scale bar: 0.1 mm.

FIGURES 57–62. Aedeagus of Mannerheimia asiatica (Figs. 57–58), M. japonica (Figs. 59–60), M. obscura (Figs. 61–62): 57, 59, 61—parameral view, 58, 60, 62—lateral view. Scale bar: 0.1 mm.

FIGURES 66–68. Aedeagus of Mannerheimia pleshanovi (paratypes): 66, 68—parameral view, 67—lateral view. Scale bar: 0.1 mm.

FIGURES 70–71. Aedeagus of Mannerheimia zanettii (paratype): 70—parameral view, 71—lateral view. Scale bar: 0.1 mm.