Contribution to the knowledge of genus Nalassus Mulsant, 1856 (Coleoptera Tenebrionidae) from the Eastern Caucasus, Russia Author Nabozhenko, Maxim V. Precaspian Institute of Biological Resources of the Daghestan Federal Research Centre of the Russian Academy of Sciences, M. Gadzhiev str., 45, Makhachkala, Republic of Dagestan 367000, Russia. & Dagestan State University, M. Gadzhiev str., 43 a, Makhachkala, Republic of Dagestan 367000, Russia. & State Natural Reserve “ Erzi ”, Pobedy str., 3, Nazran, Republic of Ingushetia 386101, Russia. Author Gadaborsheva, Mariam A. Ingush State University, I. B. Zyazikova av., 7, Magas, Republic of Ingushetia 386001, Russia. & State Natural Reserve “ Erzi ”, Pobedy str., 3, Nazran, Republic of Ingushetia 386101, Russia. text Zootaxa 2023 2023-11-02 5361 3 419 426 https://www.mapress.com/zt/article/download/zootaxa.5361.3.7/52199 journal article 10.11646/zootaxa.5361.3.7 1175-5326 10152224 9F25BE1A-01F6-4613-B2A0-C3E7929F36BD Nalassus (s. str.) magomedrasuli Nabozhenko sp. n. ( Figs 1A–C, F , 2A–C , 3A, C, D, E , 4A–D ) Nabozhenko 2001: 640 ( Nalassus kalashiani , part, only paratype ); Nabozhenko & Abdurakhmanov 2007: 188 ( Nalassus kalashiani , part, only paratype ); Abdurakhmanov & Nabozhenko 2009: 13 ( Nalassus kalashiani , part, only population from Levashi, Dagestan ); Abdurakhmanov & Nabozhenko 2011: 292 ( Nalassus kalashiani , part, only paratype ); Nabozhenko et al. 2022a: 124 , fig. 4 ( Nalassus ( Nalassus ) kalashiani ); Nabozhenko et al. 2022b: 31 , fig. 10B ( Nalassus kalashiani , part, only population from Dagestan ). Type material. Holotype , 1♁ ( ZIN ) and paratypes , 2 ♁♁, 3 ♀♀ ( ZIN , PCMN ): Russia , Dagestan , N of Levashi , 42°27ʹ55.21ʺN , 47°20ʹ31.86ʺE , limestone phryganoid mountain steppe, 1144 m , 14.06.2021 (leg. M. V . Nabozhenko, I.A . Chigray) . Paratype , ♁ (ZM MSU ): Dagestan , Levashi , 27.05.1960 , leg. D. Panfilov. Description. Male. Body length 6.8–7 mm , width 2.6–2.7 mm . Body elongate, robust, black-brown or black, dull ( Figs 1 , A, C). Head widest at eye level. Eyes small dorsally, widely spaced, weakly convex ( Fig. 2A ). Ratio of distance at widest part of head to distance between eyes 1.36–1.37. Anterior margin of epistoma straight, lateral margin of genae angulate, straight or widely emarginated in anterior two thirds. Lateral margin of head not situated between genae and epistoma. Puncturation (punctures round) of head coarse and moderately dense ( Fig. 2A ): interpuncture distance subequal to puncture diameter; puncturation little sparser on epistoma. Each puncture with short recumbent seta, better visible on fronto-epistomal depression and on temples. Head ventrally with coarse puncturation and wrinkles ahead of gula, covered with short recumbent setae ( Fig. 1C ). Apical maxillary palpomere strongly widened, axe-shaped ( Figs 1C , 2A ). Antennae moderately short, with two distal antennomeres extending beyond base of pronotum. Antennomeres thinckened, widest antennomeres 2–8 and 10 ( Fig. 1F ); antennomere 2 transverse. Length ratio of antennomeres 2–11: 1.2, 3.5, 3, 3, 2.9, 2.9, 2.7, 2.5, 2.5, 3.4. Width ratio of antennomeres 2–11: 1.6, 1.7, 1.9, 2, 2, 2.1, 2, 1.8, 2, 1.8. Ratio of length / width of antennomeres: 0.75, 2.05, 1.57, 1.5, 1.45, 1.38, 1.35, 1.38, 1.25, 1.88. Prothorax ( Figs 1C , 2A ). Pronotum transverse (1.48 times as wide as long), 1.67 times as wide as head, widest slightly behind middle ( Fig. 2A ). Lateral margins of pronotum almost straight at basal third and moderately evenly rounded after widest part to apical margin. Anterior margin almost straight, base widely weakly rounded. Angles of pronotum obtuse, widely rounded, anterior angles not projected. All margins beaded; bead of anterior margin wide and flattened (anterior bead can be interrupted in middle). Disc of pronotum moderately convex, lateral sides narrowly flattened. Puncturation of disc (punctures round) finer and sparser than on head: interpuncture distance 1.5–3 times as long as puncture diameter. Prosternum with sparse punctures in anterior half and denser smooth wrinkles puncturation in basal half. Prothoracic hypomera with longitudinal fine wrinkles and narrowly flattened outer margins. Prosternal process weakly convex at apex ( Fig. 1C ). Pterothorax ( Figs 1A, C ). Scutellar schield triangle, with slightly rounded margins and several very sparse fine punctures. Elytra elongate (1.55 times as long as wide), widest at middle, 1.9 times as wide as head, 1.14–1.15 times as wide and 2.6 times as long as pronotum. Strial punctures longitudinally elongate, connected by fine furrow. Interstriae flat, very sparsely and finely punctured (2–3 punctures in cross section). Mesoventrite pubescent by recumbent hairs, with coarse transverse wrinkles in anterior part and dense puncturation on mesocoxal process. Mesoventrite and mesepisterna with sparse and fine smooth puncturation. FIGURE 1. Nalassus spp. , habitus and details of structure. A = N. magomedrasuli sp. n. , male (holotype), habitus dorsally; B = ditto (paratype), female; C = ditto, male habitus ventrally; D = N. kalashiani , male (holotype) habitus dorsally; E = ditto, female; F = N. magomedrasuli sp. n. , male antennae; G = N. kalashiani , male. Legs comparatively thin. Trochanters with one long seta ( Fig. 1C ). Tibiae straight. Pro- and mesotarsi very weakly widened, laterally and ventrally covered with moderately short yellowish hairs ( Figs 3C, D ). Abdomen ( Figs 3A, E ). Abdominal ventrites 1–4 finely and sparsely punctured; abdominal ventrite 5 denser punctured, completely beaded at apex. First abdominal ventrite with much coarser puncturation than on other surface and hair brush; metacoxal process of abdominal ventrite 1 has much sparser puncturation in apical part ( Fig. 3A ). Male genitalia ( Figs 4A–D ). Apical piece of the aedeagus with slightly rounded lateral margins and narrowly rounded apex; median lobe of aedeagus with two straight wide alae ( Fig. 4A ). Inner sternite 6 (true VIII) with rounded apices and deep rounded emargination in middle, lobes densely pubescent ( Fig. 4B ). Spiculum gastrale with thin branches connected in long common stem and oval blades ( Fig. 4D ). IX tergite very small, evenly sclerotized (without median light line), with sparse punctures and long hairs apically ( Fig. 4C ). FIGURE 2. Nalassus spp. , details of structure. A = N. magomedrasuli sp. n. , male (holotype), head and pronotum; B = ditto (paratype), female; C = ditto, male elytral intervals; D = N. kalashiani , male (holotype), head and pronotum; E = ditto, female; F = ditto, male elytral intervals. Female ( Figs 1B , 2B ). Body more robust, with shorter, not thickened antennae (three distal antennomeres are widest). Apical maxillary palpomere less widened than in male. Lateral margins of elytra more rounded. Pro- and mesotarsi narrower, not widened. Abdominal ventrite 1 without hair brush. Comparative diagnosis. This species is similar to N. kalashiani . Differences are given in the table 1. The similar species N. faldermanni differs from N. magomedrasuli sp. n. and N. kalashiani in the large convex narrower spaced eyes (Nabozhenko at al. 2022) and very long acute apical piece of the aedeagus with straight lateral margins ( Nabozhenko 2001 ). Notes. Nalassus magomedrasuli sp. n. was originally described as Dagestan population of N. kalashiani based on the structure of the aedeagus, which is similar in both species (compare the aedeagus on Fig. 4a here and on Fig. 18 in Nabozhenko (2001)) . We studied an additional material from Dagestan and Ingushetia , again compared the holotype of N. kalashiani with males from Dagestan and collected and compared females of both populations. As a result, we describe the new species based on several diagnostic characters, mountain isolation and different habitats. The similar structure of the aedeagus can be explained by allopatric distribution of these close species. FIGURE 3 . Nalassus spp. , males, holotypes. A, C, D, E = N. magomedrasuli sp. n. ; B, F, G, H = N. kalashiani ; A, B = abdomen; C, G = protarsus; D, H = mesotarsus; E, F = middle of abdominal ventrites 1 and 2. Etymology. The new species in named in honour of Corresponding Member of the Russian Academy of Sciences Magomedrasul Dibirovich Magomedov (Precaspian Institute of Biological Resources of the Daghestan Federal Research Centre of the Russian Academy of Sciences, Dagestan , Russia ), who made a great contribution to the study of animals of the Caucasus in general and Dagestan in particular. He also organized the expedition, in which this new species was collected. Distribution and habitat. Russia , Dagestan . We collected this species in mountain steppe near Levashi (Levashi District) and one dry specimen (only elytra and abdomen) probably belonging to the new species in the similar habitat (limestone phryganoid steppe) near Verkhniy Gunib (Gunib District, Dagestan ). Adults feed on terricolous foliose lichen Cladonia pyxidata (L.) Hoffm. ( Cladoniaceae ) ( Nabozhenko et al. 2022a ).