Eodorcadion (Ornatodorcadion) gorbunovi Danilevsky, 2004

Karpiński, Lech, Enkhnasan, Davaadorj, Boldgiv, Bazartseren, Kruszelnicki, Lech, Iderzorig, Badamnyambuu, Gantulga, Temerlen, Dorjsuren, Altanchimeg & Szczepański, Wojciech T., 2021, Longhorned beetles (Coleoptera: Cerambycidae) of southeastern Mongolia with particular emphasis on the genus Anoplistes Audinet-Serville, 1833 (Cerambycinae: Trachyderini), Zootaxa 5081 (4), pp. 451-482 : 471-472

* § Eodorcadion (Ornatodorcadion) gorbunovi Danilevsky, 2004

Figs 7A–H , 10G, H , 11A, B

New records. Dornogovi: 10 km ENE of Khatanbulag [Хатанбулаг] [43.17801, 109.25925], 1141 m a.s.l., 24.07.2019, 1 larva, leg. et coll. WTS; 3 ♂♂, leg. LKa ( MIZ); 8 ♂♂, 2 ♀♀, leg. et coll. LKr; 10 km SE of Khatan- bulag [43.092, 109.207], 1222 m a.s.l., 24.07.2019, 32 ♂♂, 13 ♀♀, leg. et coll. WTS (15 exx. USMB); 26 ♂♂, 5 ♀♀, leg. LKa ( MIZ); 25 ♂♂, 15 ♀♀, leg. et coll. LKr ; 15 km SE of Khatanbulag [43.095, 109.270], 1202 m a.s.l., 24.07.2019, 11 ♂♂, 2 ♀♀, leg. et coll. WTS; 4 ♂♂, 2 ♀♀, leg. LKa ( MIZ); 20 ♂♂, 5 ♀♀, leg. et coll. LKr ; 42 km SE of Khatanbulag [42.804, 109.382], 1100 m a.s.l., 25.07.2019, 10 ♂♂, 3 ♀♀, leg. et coll. WTS; 7 ♂♂, 1 ♀, leg. LKa ( MIZ); 9 ♂♂, 3 ♀♀, leg. et coll. LKr ; 43 km SE of Khatanbulag [42.795, 109.356], 1099 m a.sl., 25.07.2019, 6 ♂♂, 3 ♀♀, leg. et coll. LKr .

Literature data. Dornogovi: Mt. Khutag-Uul [г. Хутаг-Ула], N of Sulin-Kheer [Сулин-Хэрэ] [ca. 42.968, 109.452], under Caragana , 27.06.1971, 1 ex. ( Namhaidorzh 1976a: as Eodorcadion oryx ); 25 km E of Shokhoi- Nuur Lake [оЗ. Пюхой-Нур] [ca. 42.776, 109.366], 03.08.1971, 2 exx. (ibid); 7 km SW Khatanbulag, [43.116, 109.050], 1120 m a.s.l., 8– 9.07.2002, 1 ♂ holotype, M. Danilevsky, leg. (MD), 10 ♂♂, 9 ♀♀, M. Danilevsky and O. Gorbunov leg. (Danilevsky 2004, 2007); 11 km SE Khatanbulag [43.100, 109.266], 1240 m a.s.l., 9.08.2002, 34 ♂♂, 15 ♀♀, M. Danilevsky and O. Gorbunov leg. (ibid); 24 km SE Khatanbulag [43.016, 109.383], 1000 m a.s.l., 9.08.2002, 15 ♂♂, 3 ♀♀, M. Danilevsky and O. Gorbunov leg. (ibid); 23 km SE Khatanbulag [43.066, 109.416], 1000 m a.s.l., 9.08.2002, 1 ♂, O. Gartumnov leg. (ibid).

Remarks. Eodorcadion gorbunovi is a relatively recently described species from the environs of Khatanbulag (Danilevsky 2004). Besides the localities provided in the original description (Danilevsky 2004), also the two records mistakenly given for E. argaloides by Danilevsky (2007) should be included for the known area of E. gorbunovi : 25 km E of Shokhoi-Nuur Lake and Mt. Khutag-Uul (see more in the remarks for E. argaloides ). However, according to the local scientists, the location of Mt. Khutag-Uul needs to be verified as it is situated more to the southeast ( Fig. 4 ).

This species inhabits depressions of stony hills that are overgrown with Lasiagrostis Link (= Achnatherum ) ( Danilevsky (2007), and according to Namhaidorzh (1976a) it is ecologically associated with Lasiagrostis , Stipa L. ( Poaceae ), and Caragana . Our own observations (for closely related E. intermedium kozlovi ) indicate that while larvae indeed feed on roots of these grass species, leaves and stems of Caragana bushes serve as food and a night shelter for the adults.

We have investigated several suitable sites in the range of this species and found numerous imagines, as well as a single larva among Achnatherum roots, approx. 30 cm deep in the soil ( Fig. 10G ). It is worth noting that despite usually abundant occurrence of adults, it was difficult to find any premature stages in the soil and we succeeded only once, in spite of several attempts at various depths. The sites were located within regular semi-desert with enclaves of Achnatherum splendens (Trin.) Nevski ( Fig. 10F ). Single individuals were also collected in a narrow canyon near a dried riverbed. In one of the sites, we have observed individuals rapidly hiding in Achnatherum tufts during the rain. When the weather started to improve and the sun came out, the individuals started to climb onto the stems of grass ( Fig. 10H ), most likely to dry faster in the wind and bright sun.

We found solely individuals of this species in the locality west of Shokhoi-Nuur Lake, where, in accordance with Danilevsky (2007), E. argaloides occurs (see the discussion above and remarks for E. argaloides ). The imagines ( Fig. 11A, B ) were collected in semi-desert habitat in the immediate vicinity of a dried lake ( Fig. 11C ), relatively densely overgrown with Achnatherum . We find no differences between the individuals collected in this plot ( Fig. 7E–H ) and those from the type locality (and its vicinity) of E. gorbunovi ( Fig. 7A–D ). The discussed sites are distanced only approx. 35 km in a straight line from each other, though it should be noted that we have not seen suitable grassy habitats on the way (barren rocky desert). Nevertheless, despite the fact that the similar distance separates these southernmost localities of E. gorbunovi from the confirmed localities of E. argaloides , definitely stronger geographical barriers in a form of ranges of rocky hills exist between them.

Figures

FIGURE 4. Literature and new records of representatives of the genus Eodorcadion in the region of SE Mongolia (raster layer: OpenTopoMap).

FIGURE 7. Habitus of longhorned beetle taxa distributed in the region of SE Mongolia (genus Eodorcadion). A, Eodorcadion gorbunovi (male, type locality area); B, E. gorbunovi (male, ibid); C, E. gorbunovi (female, ibid); D, E. gorbunovi (female, ibid); E, E. gorbunovi (male, Shokhoi-Nuur Lake area— erroneous locality of E. argaloides); F, E. gorbunovi (male, ibid); G, E. gorbunovi (female, ibid); H, E. gorbunovi (female, ibid); I, Eodorcadion intermedium kozlovi (male); J, E. intermedium kozlovi (male); K, E. intermedium kozlovi (female); L, E. intermedium kozlovi (female). Scale bar: 5 mm.

FIGURE 10. Photographs of adults and larvae in situ and habitats of typical SE Mongolian cerambycid species. A, stony hills with dense shrub vegetation, including Zygophyllum, most likely habitat of Anoplistes kaszabi; B, saxaul and tamarisk shrubs in strongly desertified area in southern Mongolia, most likely typical habitat of Anoplistes mongolicus; C, male of Eodorcadion exaratum argali; D, female of E. exaratum argali under cow dung; E, melanistic female of E. exaratum argali; F, Achnatherum splendens enclave in semi-desert area, habitat of Eodorcadion gorbunovi; G, freshly digged larva of E. gorbunovi; H, male of E. gorbunovi climbing onto stems of grasses.

FIGURE 11. Photographs of adults and larvae in situ and habitats of typical SE Mongolian cerambycid species. A, male of Eodorcadion gorbunovi in Shokhoi-Nuur Lake area (erroneous locality of E. argaloides); B, female of E. gorbunovi (ibid); C, semi-desert habitat with dried lake overgrown with Achnatherum splendens, habitat of E. gorbunovi (ibid); D, male of Eodorcadion intermedium kozlovi hiding in Caragana bushes after the night; E, female of E. intermedium kozlovi feeding on Caragana leaves; F, male of E. intermedium kozlovi climbing onto stems of grass; G, female of E. intermedium kozlovi; H, A. splendens enclave between Mandakh and Sainshand, typical habitat of E. intermedium kozlovi.