Anthobium tenue ( Eppelsheim, 1881 )

Shavrin, Alexey V., 2024, Review of the genus Anthobium Leach, 1819 (Coleoptera: Staphylinidae: Omaliinae) of Western Palaearctic region, Zootaxa 5537 (4), pp. 451-474 : 464-468

Anthobium tenue ( Eppelsheim, 1881)

( Figs 21 , 26–27 , 32 )

Lathrimaeum tenue Eppelsheim, 1881: 507 ; Luze 1905: 60, Bordoni 1986: 43.

Lathrimaeum (Lathrimaeum) tenue : Scheerpeltz 1961: 80.

Anthobium tenue : Assing & Schülke 2019: 98.

Type material examined. Lectotype of Lathrimaeum tenue Eppelsheim, 1881 (here designated) ♂ ( Fig. 21 ; dissected prior to the present study): ‘Kaukas | Leder | Suram [handwritten]’ <printed>, ‘c. Eppelsh. | Steind. d.’ <printed>, ‘TYPUS’ <red, printed>, ‘tenue Epp. | det. [printed] Luze’ <handwritten>, ‘ LECTOTYPE | Lathrimaeum | tenue Eppelsheim, 1881 | Shavrin A.V. des. 2024’ <printed>, ‘ Anthobium | tenue ( Eppelsheim, 1881) | Shavrin A.V. det. 2024’ <printed> ( NMW). Paralectotype ♀: ‘Suram’ <handwritten>, ‘Kaukas | Leder’ <printed>, ‘coll. Reitter’ <printed>, ‘ Holotypus [printed in red] 1880 | Lathrimaeum | tenue | Eppelsheim’ <handwritten label with red margins>, ‘ Lathrimaeum | tenue Epp. | det. Székessy [printed]’ <handwritten>, ‘ Anthobium | tenue ( Eppelsheim, 1881) | Shavrin A.V. det. 2024’ <printed> ( HNHM).

Additional material examined. RUSSIA: KARACHAY-CHERKESSIA: 1 ♀: Teberda State Nature Biosphere Reserve, Malaya Khatipara Mt. 1700 m a.s.l. 30.05.1985. A.B. Ryvkin leg. (cR); 1 ♀: same Reserve. 1.06.1985. A.B. Ryvkin leg. (cSh); GEORGIA: SVANETI: 1 ♀: ‘Caucasus Swanetien Leder Reitter’, ‘ Lathrimaeum tenue Epp. Coll. Reitter’ ( HNHM); 1 ♀: ‘Caucasus. Swanetien. Leder. Reitter’, ‘352’, ‘tenue Epp. det. Luze’ ( NMW); 1 ♂: ‘ ♂ ’, ‘Caucasus. Swanetien. Leder. Reitter’, ‘tenue Epp. det. Luze’, ‘ex. coll. Skalitzky’ ( NMW); 1 ♂: ‘ ♂ ’, ‘Caucasus. Swanetien. Leder. Reitter’, ‘tenue Epp. det. Luze’, ‘ex. coll. Scheerpeltz’ ( NMW); SHIDA KARTLI: 2 ♂♂, 4 ♀♀: Surami (=Ricoti) pass, ca. 1000 m a.s.l., forest with Fagus , Alnus , Castanea and Rhododendron , litter and under stones. 14.04, 17.05.1983. S.I. Golovatch leg. (cR, cSh, ZMM); SAMTSKHE-JAVAKHETI: 1 ♂, 1 ♀: ‘Caucasus Meskisches Geb. Leder, (Reitter)’, ‘ Lathrimaeum tenue Epp. Coll. Reitter’ ( HNHM); SAMTSKHE-JAVAKHETI: 1 ♂: ‘Caucasus Abastuman Leder, (Reitter) Lathrimaeum tenue Epp. Coll. Reitter’ ( HNHM); CAUCASIAN REGION WITHOUT EXACT LOCALITIES: 1 ♂, 1 ♀: ‘Caucasus Circassien Leder. Reitter Lathrimaeum tenue Epp. Coll. Reitter’ ( HNHM); 2 ♂♂: ‘Caucasus Leder.Reitter’, ‘ Lathrimaeum tenue Epp. Coll. Reitter’ ( HNHM); 1 ♀: ‘Kaukas Leder,’, ‘c. Eppelsh. Steind. d.’, ‘tenue Epp. det. Luze’, ‘TYPUS’ ( NMW); 1 ♀: ‘Kaukas Leder’, ‘c. Eppelsh. Steind. d.’, ‘tenue Eppelsh. Vrch. zool. bot. Ges. Wien, 1880, p. 507’, ‘TYPUS’ ( NMW); 1 ♂, 1 ♀: ‘Kaukas Leder’ ( HNHM); 1 ♀: ‘ ♀ ’, ‘Kaukas Leder’, ‘Reitter’, ‘tenue Epp. ’, ‘355’, ‘ex. coll. Skalitzky’ ( NMW).

Redescription. Measurements (n=20): HL: 0.37–0.45; HW: 0.64–0.72; AL: 1.45 (holotype); OL: 0.11–0.12; PL: 0.61–0.63; PW: 1.14–1.27; ESL: 1.29–1.44; EW: 1.30–1.60; AW: 1.27–1.50; MTbL: 0.67 (holotype); MTrL (holotype): 0.34 (MTrL 1–4: 0.22; MTrL 5: 0.12); AedL: 0.70–0.72; TL: 2.60–3.70 (lectotype: 3.35).

Habitus as in Fig. 21 . Body yellow-brown to reddish-brown (some specimens with slightly darker head and abdomen); antennomeres 3–11 or 4–11 brownish (paler specimens with yellowish antennomeres); mouthparts, antennomeres 1–2 or 1–3 and legs yellow to yellow-brown. Head with transverse fine microreticulation in frontal portion, indistinct subdiagonal meshes in middle and dense, fine, transverse or subdiagonal microreticulation on laterobasal portions (some specimens without visible sculpture in middle). Head with moderately dense and irregular punctation, finer and sparser in middle, denser and sometimes deeper on infraorbital portion and between ocelli; neck with dense, regular and moderately fine punctation; pronotum with very dense, moderately fine punctation, with interspaces between punctures in middle about as long as diameters of one-two nearest punctures, usually finer and sparser in mediobasal portion; punctation of elytra about as that on pronotum, but sometimes slightly coarser and deeper in mediobasal part.

Head 1.6–1.7 times as broad as long, with slightly or strongly elevated median portion; anteriomedian depressions moderately wide and deep, connected with relatively deep lateral depressions; postocular ridges acute, with interspace between posterior margin of eyes and ridge about as long as three nearest ommatidia. Ocelli moderately large, located at level or slightly below level of postocular ridges. Antennomere 4 distinctly shorter than 3, 5–7 slightly longer and indistinctly broader than 4, 8 slightly shorter and broader than 7, 9–10 slightly broader than 8.

Pronotum 1.8 times to twice as broad as long, from widest middle gradually narrowed both anteriad and posteriad; posterior angles obtuse; apical angles slightly protruded anteriad; middle portion usually without longitudinal elevation except of some specimens with shallow traces of it, mediobasal depression missing or indistinct.

Elytra 1.1 times as long as broad, slightly more than twice as long as pronotum, reaching apical margin of abdominal tergites V–VII, slightly broadened posteriad; middle surface of each elytron usually with irregular longitudinal elevations between punctures.

Male. Apical margin of abdominal tergite VIII truncate. Apical margin of abdominal sternite VIII sinuate. Aedeagus with very wide basal portion, gradually narrowed toward wide truncate apex; parameres indistinctly exceeding apex of median lobe, slightly broadened in preapical portions, with four small apical setae; internal sac long and moderately narrow, spirally folded in basal portion, with wide field of acute spines in middle part ( Fig. 26 ). Lateral aspect of the aedeagus as in Fig. 27 .

Female. Apical margins of abdominal tergite VIII and sternite VIII truncate.

Comparative notes. Based on the general shape, the coloration and the length of the body, A. tenue is similar to widespread A. unicolor , from which can be distinguished by more transverse pronotum with significantly more protruded apical angles, the shape of the broader parameres and details of the structure of the internal sac.

Distribution. Anthobium tenue is known from several localities in Caucasus ( Fig. 32 ).

Bionomics. The detailed bionomical data for the most studied specimens is unknown. Some specimens were collected at elevations from 1000 to 1700 m a.s.l. and were sifted from litter of deciduous forests.

Remarks. Lathrimaeum tenue was originally described from “Suramgebirge” based on “Wenige Stücke”. During the study of collections of NMW and HNHM I found two specimens collected in “Suram”. Thus, the male from NMW was designated as the lectotype in order to fix the indentity of the name. It is here recorded from Russia for the first time.

Figures

FIGURE 32. Distribution of Anthobium tenue in Caucasus.

FIGURES 19–23. Habitus of Lathrimaeum (types) and Anthobium: 19–L. moczarskii (holotype), 20–L. metallicum (holotype), 21–L. tenue (lectotype), 22–L. laterale (holotype), 23–A. ganglbaueri (Turkey, Ulu Dað). Scale bar: 1.0 mm.

FIGURES 24–30. Aedeagus of Anthobium (Figs 24–25: A. moczarskii (Spain, Pinilla del Valle), Figs 26–27: A. tenue (Georgia, Surami Pass), Fig. 28: A. ganglbaueri (Turkey, Bademli), Figs 29–30: A. ganglbaueri (Turkey, Kastamonu): 24, 26, 28–29– parameral view, 25, 27, 30–lateral view. Scale bar: 0.1 mm.