Lethrus (Lethrus) schneideri Kral & Hillert

Kral, David, Hillert, Oliver, Drozova, Dana & Sipek, Petr, 2013, Lethrus (Lethrus) schneideri sp. n. (Coleoptera, Geotrupidae) from Greece, ZooKeys 339, pp. 93-106 : 95-101

Lethrus (Lethrus) schneideri Kral & Hillert sp. n. Figures 1C, F; 2C, F; 3C, 4C, F; 5 C–E; 7; 8 A–B

Type locality.

Greece, E Macedonia & Thrace province, Rhodope district, Komotiní environment, Karydia, approx. 120 m a.s.l., 41°06.10'N, 25°24.58'E (Fig. 8B).

Type material

(169 specimens). Greece: Holotype ♂, allotype ♀ (DKCP), "GR, E Macedonia & Thrace, 19.iv. / Rodopi dist., Komotiní env., / KARYDIA, 41°06.10'N, 25°24.58'E / D. Král, D. Drožová, H. Podskalská, P. Šípek & A. Venderová lgt., 2009 [p] ". Paratypes: 5 ♂♂, 10 ♀♀ (DKCP), 3 ♂♂, 3 ♀♀ (JSCP), same data; 47 ♂♂, 20 ♀♀ (OHCB), 4 ♂♂, 2 ♀♀ (DKCP), 2 ♂♂, 2 ♀♀ (JSCP), "Greece, (Thrace), / N of Komotini, military area / 10.04.2011, leg. O. Hillert [p]"; 29 ♂♂, 10 ♀♀ (PTCL) 1 ♂, 1 ♀ (JSCP), "Greece, Thracie / Komotini, 2,1 km SZ Karydia / 41.155846, 25.422836 / 29.4.2012, leg. Pavel Turek [p]"; 14 ♂♂, 22 ♀♀ (ZLCK) 1 ♂ 1 ♀ (JSCP), "Greece, Komotini / 2,1 Km SZ Karydia / 41°8'59.19"N, 25°25'31.14"E / 29.4.2012, leg. Z. Lucbauer [p]".

Additional material examined.

6 specimens). Greece: 1 ♂, 2 ♀♀ (NMPC), 1 ♂, 1 ♀ (OHCB), "Xanthi, Gr. / 14.v.1937 / coll. Barton [p]"; 1 ♂ (MNHN), “Grèce [p]".

Description of holotype.

Maximally developed male with well developed ventral mandible processes (Figs 4C, F; 5C). Total body length 29 mm. Oblong, strongly convex; dorsal surface black, moderately shiny, except almost alutaceous pronotum; ventral surface black with fine blue tinge, moderately shiny, claws black-brown; macrosetation black.

Head (Figs 1C, F; 2C; 4C, F; 5C). Labrum bilobed, asymmetrical, right lobe remarkably more developed; surface rugosely and coarsely, shallowly and sparsely punctate, each puncture bearing short recumbent macroseta; anterior margin with dense row of long macrosetae. Clypeus transverse, trapezoidal with anterior angles round. Frontal impressions vague, frontal tubercles indistinct. Frontoclypeal suture present only laterally; keels separating eye canthus from frons only slightly developed but distinct, slightly divergent posteriad. Eye canthus exceeding eyes, projecting anterolaterad, almost rectangular, lateral margins divergent posteriad, anterolateral angle round, oblique keel above eyes absent. Pleurostomal process evenly arcuate, hardly exceeding ventrolateral mandible outline. Punctation of frons double, consisting of coarse, transversally rugose, regularly and densely distributed punctures, intermixed with fine, irregularly distributed ones; coarse punctures separated by approximately less than their diameter, punctation becoming distinctly sparser posteriad and on occiput; clypeus and eye canthus distinctly rugose.

Mandibles symmetrical, external outline almost semicircular, pointed subapically in dorsal aspect (Figs 1C, 4C) with maximum width approximately at middle of mandibles length.

Ventral mandible processes (Figs 1F, 2C, 4F, 5C) weakly asymmetrical, right process slightly more developed than left one and with different angle in lateral aspect. Both processes distinctly longer than length of mandible; base thickened, not exceeding lateral mandibular outline in dorsal aspect, with slightly concave external outline in basal half in frontal aspect; longitudinal keel on base laterally present, straight and distinctly subparallel to lateral mandibular outline, approximately as broad as maximum width of mandibles outline basally; in lateral aspect weakly arcuate, approximately subparallel to lateral mandibular outline, slightly divergent gradually basad approximately from middle of its length. Inferiobasal tooth absent; both processes bent inward approximately in middle of mandibles length in frontal view; anterior subapical tooth absent; apical emargination absent; apical tooth round.

Pronotum (Figs 2F; 4C, F; 5C) transverse, distinctly broader than base of elytra, broadest just behind middle; margin entirely bordered, slightly crenulate in anterior parts. Anterior angles weakly but distinctly projecting anterolaterad, with angulate outline; lateral margin approximately weakly emarginate anteriorly, then straight to round posterior angle; basal margin straight. Punctation of dorsal surface simple, consisting of deep, sparsely and irregularly distributed punctures; punctures separated by approximately two to four their diameters discally, surface near lateral margins considerably shagreened and alutaceous.

Scutellar shield widely triangular, finely shagreened.

Elytra almost semicircular, apices not prominent, each apex forming independent arc. Epipleuron strongly narrowed apicad, epipleural keel not reaching elytral apex. Whole surface alutaceous, finely transversally rugose; striae not indicated, entirely vanishing in rugosities.

Legs. Profemur not armed, protibia with row of eight gradually proximad diminishing external denticles, and with row of tubercles on ventromedial edge.

Aedeagus as in Fig. 3C.

Variability in males.

Body length 19-30 mm. Mandible processes in medium developed and underdeveloped (hypothelic) males short, more or less straight with simply rounded to almost acute apically.

Females

(body length 18-24 mm, allotype 24 mm - Figs 5D, E) differ from males as follows: external outline of mandibles almost straight, in apical quarter round in dorsal aspect (Fig. 5D); ventral mandibular process absent (Fig. 5E); protibia broader, row of tubercles on ventromedial edge less pronounced.

Differential diagnosis.

Among the species distributed in the Balkan Peninsula, the new species is most similar and probably closely related to Lethrus (Lethrus) ares Král, Rejsek & Schneider, 2001 and Lethrus (Lethrus) apterus (Laxmann, 1770). Distinguishing features are: absence of anterior subbasal tooth of ventral mandibular processes ( Lethrus (Lethrus) schaumii Reitter, 1890 and Lethrus (Lethrus) elephas Reitter, 1890 have distinct anterior subbasal tooth); absence of anterior subapical tooth of ventral mandibular processes ( Lethrus (Lethrus) halkidikiensis Hillert & Král, 2013, Lethrus (Lethrus) perun Hillert & Král, 2013, Lethrus (Lethrus) raymondi Reitter, 1890 and Lethrus (Lethrus) strymonensis Hillert & Král, 2013 have distinct anterior subapical tooth); presence of approximately symmetrical ventral mandibular processes and regularly round or obtuse-angular anterior pronotal angles ( Lethrus (Lethrus) fallax Nikolajev, 1975 and Lethrus (Lethrus) liviae Pittino, 2011 have remarkably asymmetrical ventral mandibular processes and strongly produced acute-angular anterior pronotal angle). For characters to separate Lethrus (Lethrus) apterus , Lethrus (Lethrus) ares , and Lethrus (Lethrus) schneideri sp. n. see the character matrix (Table 1). Additionally, Lethrus (Lethrus) schneideri sp. n. is probably an endemic species of the southernmost slopes of the Rhodope Mountains approximately between the towns of Xánthi and Komotiní, while Lethrus (Lethrus) ares is known so far only from four spots all situated in the Eridropótamos river basin (Fig. 7) and Lethrus (Lethrus) apterus is a widely distributed Pannonian species known from Burgenland (Austria), Moravia (Czech Republic) and Serbia in the west to the Don river basin in the east (Fig. 6). The geographic range of the latter is separated from that of the new species by the Thracian lowlands in Bulgaria inhabited by Lethrus (Lethrus) schaumii ,and by the Rhodope Mountains.

Collecting circumstances.

The type series was collected from uncultivated fields on moderately steep, approximately SE oriented slope consisting of loess soil (Figs 8 A–B) in a millitary area.

Distribution.

Greece: Thrace, southernmost foothills of the Rhodope (Ροδόπη) Mountains. (Fig. 7), the regional units of Rhodope and Xánthi.

Name derivation.

Patronymic, named in honour of our longtime friend, entomologist Jan Schneider (Praha, Czech Republic), an excellent Geotrupidae and Silphidae specialist.