Lethrus (Autolethrus) toropovi Shapovalov, 2022

Shapovalov, Andrey M., 2022, New species of the genus Lethrus Scopoli, 1777 (Coleoptera: Geotrupidae: Lethrinae) from Fergana Valley, Kyrgyzstan, Zootaxa 5159 (3), pp. 414-424 : 415-423

Lethrus (Autolethrus) toropovi Shapovalov , new species

( Figs. 1–4 , 12 , 15–17 )

Type locality. Kyrgyzstan, Jalal-Abad Region , 5 km ENE of Kyzyl-Tokoi village, 41°24'N 71°23'E, 1250 m a.s.l.

Type material (158 specimens). Holotype, ♂ ( ZIN), “ Kyrgyzstan, Jalal-Abad Reg. , 5 km ENE Kyzyl-Tokoi vill., 41°24'N 71°23'E, h = 1250m, 28.III.2021, S.A. Toropov leg.” . Paratypes: allotype, ♀ ( ZIN) and 75 ♂♂, 42 ♀♀ ( ASPC), same data as holotype ; 15 ♂♂, 12 ♀♀ ( ASPC) , 3 ♂♂, 3 ♀♀ ( ZIN) , 5 ♂♂ ( MBPC), but 22.IV.2019 ; 1 ♂ ( MBPC), “ Kyrgyzstan, Jalal-Abad Reg. , 15 km SE Tereksai, 30.V.1989 ” .

Description. Male (holotype ♂). Maximally developed (hyperthelic) male. Body length with closed mandibles 24.4 mm, body length to clypeal margin 22 mm, width of pronotum 12.5 mm.

Body ( Fig. 1 ) oblong, strongly convex; dorsal surface shiny, mostly with aenescent-bronze tinge; anterior part of head, mandibles, antennae, partly lateral sides of pronotum, elytra, ventral side and legs with bluish tinge.

Head ( Figs. 1 , 15 ). Labrum bilobed, right lobe weakly more developed than left one; anterior margin with dense row of long setae. Clypeus transverse, trapezoidal with rounded anterior angles. Frontal impressions and frontal tubercles slightly developed. Frontoclypeal suture present only laterally. Keels separating gena from frons distinct, slightly arcuate. Gena exceeding eyes, projected laterally, in dorsal aspect almost twice greater (maximal distance from outer eye margin up to inner margin of gena) than eye width, lateral margin narrowly and obliquely truncate. Postorbital denticles absent. Pleurostomal process directed downward, relatively long, at distal part narrowed, distinctly exceeding ventrolateral mandible outline. Sculpture finely rugose with relatively dense, double in size punctation on anterior part of head, laterally on frons and along midline; remaining dorsal surface of head with smoothed sculpture and sparse punctation; gena with fine rugose sculpture, punctures scattered and superficial.

Mandibles ( Figs. 1 , 12 , 15 ) nearly symmetrical, with almost semicircular outer margin, left mandible subapically slightly emarginate, maximum width at about middle of mandible length. Ventral mandibular processes ( Fig. 12 , 15 ) almost symmetrical with slightly different direction of apices in lateral aspect; processes outgrowing from subapical part of mandibles. Both processes distinctly longer than length of mandible; weakly exceeding lateral mandibular outline in dorsal aspect, strongly curved inward from proximal 2/3 half in frontal aspect; longitudinal keel on base noticeably not reaching mid length of processes, keel obtuse and weakly elevated, in frontal projection forming small tubercle; dorsal mandible keels parallels to anterior margin of mandibles; anterior margin with obtuse tooth distally of the middle, distinctly emarginated between tooth and apex; in lateral aspect apex of left process directed downward, apex of right process slightly curved and directed down and backwards.

Pronotum ( Figs. 1 , 12 ) transverse, distinctly broader than base of elytra, with maximum width behind middle; margins entirely bordered, anteriorly weakly crenulate. Anterior angles rounded; posterior angles widely rounded. Punctation fine, sparse, more dense and coarse only on transversal area near midline; microsculpture dense on lateral sides and weakly pronounced on the disc, surface of disc mostly shiny, lateral sides nearly matt.

Elytra ( Fig. 1 , 12 ) almost semicircular, apices not prominent and together rounded, epipleuron strongly narrowed apicad, epipleural keel not reaching elytral apex; with scattered small punctures, weakly shagreened, surface of disc mostly shiny, lateral and posterior elytral slope matt, striae fine and shallow.

Legs ( Fig. 1 , 12 ). Protibia moderately elongated and curved inside, with nine external teeth gradually proximad diminishing, and with row of tubercles on ventromedial edge.

Male genitalia ( Figs. 3–4 ). Aedeagus with parameres sinuate distally in lateral aspect, apically parameres form oblong lobes.

Variability in males. Body length with closed mandibles 18.5–26 mm, body length to clypeal margin 16.9–23 mm, width of pronotum 9.8–12.5 mm. In moderately developed and poorly developed (hypothelic) males mandibular processes on anterior margin with small, but distinct obtuse tooth; longitudinal keel on the base of processes straight; pleurostomal process comparatively short; hind tibia weakly elongated and curved inside ( Fig. 17 ). Metallic tinge of dorsal surface of body often weakly developed or absent in older specimens, in latter case dorsal surface black, more or less shiny. Sometimes elytral striae comparatively deep or striae indistinct.

Females ( Fig. 2 ). Body length with closed mandibles in allotype 21 mm, body length to clypeal margin 18.3 mm, width of pronotum 11.4 mm. Variability in females: body length with closed mandibles in 17–23 mm, body length to clypeal margin 15.9–21 mm, width of pronotum 9.5–12.6 mm. Frontal tubercles often slightly more developed than in males. External outline of mandibles almost straight, in apical third rounded in dorsal aspect; mandibles without ventral processes, pleurostomal process less developed. Elytral apices slightly projecting or both forming short pointed or rounded process. Protibia shorter and slightly less directed inside than in males, row of tubercles on ventromedial edge less developed.

Distribution. The new species is known only from Kyrgyzstan: two close localities (distance between them about 7 km) in north part of the Fergana Valley on the south macroslope of the central part of the Chatkal Mountain Range along the Kassan-Say River Valley. On the east part of the Chatkal Mountain Range (at least from near Kerben) L. toropovi Shapovalov , new species is replaced by L. tshatkalensis , that is distributed on south-east slopes of Chatkal Range (Arkit, Sary-Chelek), eastern mountain spurs of this range (Bozbu-Too Mts.) and foothills on the right bank of the Naryn River westwards Tash-Kumyr (see map, Fig. 11 ).

Differential diagnosis. The new species is most similar to Lethrus tshatkalensis , but clearly distinguished by the shape of mandibular appendix ( Figs. 12 , 15–17 ). Longitudinal keel on base of mandibular processes in L. toropovi Shapovalov , new species ( Figs. 12 , 15–17 ) is weakly elevated, in frontal projection forming proximally only small tubercle or straight (latter case most often in moderately developed and poorly developed (hypothelic) males); anterior margin of processes with tooth distal to the middle, between tooth and apex distinctly emarginated, in the smallest poorly developed (hypothelic) males with distinct small tooth before apex ( Fig. 17 ). Longitudinal keel on the base of mandibular processes in L. tshatkalensis ( Figs. 13–14 , 18–20 ) is sharp and prominent, before middle abruptly breaking off and forming distinctly protruding projection, which looks in frontal and latero-frontal aspect like an acute tooth or obtuse-angular lobe; only one studied extremely poor developed (hypothelic) male without such a lobe, but keel elevated ( Fig. 20 ); anterior margin of processes with only obtuse protrusion, shallowly arcuate before apex. Shape of aedeagus of the two species lack distinct differences ( Figs. 3–6 ).

In males of other species of the L. sulcipennis -group, anterior margin of processes lacks tooth ( Figs. 21–26 ), the longitudinal keel on the interior surface of the processes in maximally (hyperthelic) and medium developed males sharp, and keel reaching to the middle of process-length in L. mucronatus ( Figs. 21–22 ) or exceeding the middle in L. sulcipennis ( Figs. 24–25 ). Also, maximally (hyperthelic) and medium developed males of L. sulcipennis ( Figs. 24–25 ) have asymmetrical mandibular processes; medium developed males of L. sulcipennis with tooth or angulate protrusion on longitudinal keel of appendage only on right mandible, tooth situated after middle of processlength ( Fig. 25 ); poor developed males can lack any distinct protrusion, but processes apically directed inside ( Fig. 26 ). In medium developed males of L. mucronatus both processes near middle of length interiorly with angulate protrusion on longitudinal keel ( Fig. 22 ); in poor developed males processes without distinct protrusion, but thinner apically ( Fig. 23 ). Also, L. sulcipennis and L. mucronatus differs from L. toropovi Shapovalov , new species and L. tshatkalensis by the shape of the parameres ( Figs. 3–10 ).

Females of L. toropovi Shapovalov , new species ( Fig. 2 ) can be distinguished from L. tshatkalensis only by the partly shiny surface of the dorsal side of the body, while in L. tshatkalensis the surface is weakly shiny, nearly matt. Females of the other two species of the sulcipennis -group are hardly distinguishable, but L. mucronatus have more or less elevated, sometimes comparatively sharp edge of the clypeus (this character is also present in males) and usually more prominent frontal tubercles, in more or less fresh specimens the dorsum has a slight bluish tinge; in L. sulcipennis the striae of the elytra are more noticeable than in other species of group, and more or less fresh specimens have a bronze tinge.

Etymology. The species is named in honour of Sergei Akindinovich Toropov (Bishkek, Kyrgyzstan)— entomologist, ornithologist, and nature-photographer, and also collector of most of the type series.

Ecology. Activity of beetles recorded from late March to the end of May in steppe biotopes at altitude about 1250 m a.s.l.

Figures

FIGURE 11. Map of distribution Lethrus (Autolethrus) spp. Lethrus toropovi Shapovalov, new species: 1—type locality, 5 km ENE Kyzyl-Tokoi; 2—15 km SE Tereksai. Lethrus tshatkalensis Protzenko, 1965: 3—approximate point for localities near Nanai (“Nanay, adyrs” and “Nanai, Kok-sarai”); 4—approximate point near Kerben for locality “Karavanskaya Valley”; 5—Abysheva Pass, Bozbu-Too Mts.; 6—Torkamysh env., Bozbu-Too Mts.; 7—Arkit (type locality), Chatkal Mountain Range; 8—bank of Sary-Chelek Lake, 1850 m a.s.l., Chatkal Mountain Range (record of Protzenko 1965); 9—5 km W Tash-Kumyr; 10—right bank of Naryn Riv. 1–2, 4–10—Kyrgyzstan, Jalal-Abad Reg.; 3—Uzbekistan, Namangan Reg.

FIGURES 1–10. Lethrus (Autolethrus) sulcipennis-group from Kyrgyzstan. 1–4, L. toropovi Shapovalov, new species from type locality (holotype, male—1; allotype, female—2; paratype, male—3–4); 5–6, L. tshatkalensis Protzenko, 1965 (15 km SE Kerben, Bozbu-Too Mts.); 7–8, L. mucronatus Semenov, 1894 (Kyzyl-Dzhar, southern promontories of Bozbu-Too Mts.); 9–10, L. sulcipennis Kraatz, 1883 (Kara-Kulja env., extreme SE of Fergana Mountain Range). 1–2 habitus, 3–10 aedeagus (3, 5, 7, 9—ventral view; 4, 6, 8, 10—lateral view).

FIGURES 12–14. Lethrus (Autolethrus) spp., habitus of males in left oblique view, from Kyrgyzstan, Jalal-Abad Reg. 12, Lethrus toropovi Shapovalov, new species, holotype; 13–14, L. tshatkalensis Protzenko, 1965: 13—15 km SE Kerben; 14— Sary-Chelek (photograph: M. Smirnov).

FIGURES 15–26. Lethrus (Autolethrus) sulcipennis-group, male head in frontal view, specimens from Kyrgyzstan: 15–17, L. toropovi Shapovalov, new species (15—holotype, 16–17—paratypes); 18–20, L. tshatkalensis Protzenko, 1965; 21–23, L. mucronatus Semenov, 1894; 24–26, L. sulcipennis Kraatz, 1883. 15–17—5 km ENE Kyzyl-Tokoi; 18, 20—15 km SE Kerben, Abysheva Pass, Bozbu-Too Mts.; 19, 22–23—5 km W Tash-Kumyr, Jalal-Abad Reg., southern promontories of Bozbu-Too Mts.; 21—Kyzyl-Dzhar, southern promontories of Bozbu-Too Mts.; 24—Kara-Kulja env., extreme SE of Fergana Mountain Range; 25–26—Almalyk env., Alai Mountain Range.