The millipede genera Amblyiulus Silvestri, 1896 and Syrioiulus Verhoeff, 1914 in the Caucasus, with notes on their distributions (Diplopoda, Julida, Julidae) Author Evsyukov, Aleksandr P. https://orcid.org/0000-0001-5521-7563 Don State Technical University, Department of Biology and General Pathology, Rostov-on-Don, Russia aevsukov@mail.ru Author Golovatch, Sergei I. Institute for Problems of Ecology and Evolution, Russian Academy of Sciences, Moscow, Russia Author Antic, Dragan Z. https://orcid.org/0000-0002-1231-4213 University of Belgrade, Faculty of Biology, Institute of Zoology, Belgrade, Serbia text ZooKeys 2021 2021-07-13 1048 109 143 http://dx.doi.org/10.3897/zookeys.1048.68454 journal article http://dx.doi.org/10.3897/zookeys.1048.68454 1313-2970-1048-109 FC201D049877458392C284CC80BB75A5 CC5A95B22B135366B9E84778E8FC3020 Amblyiulus hirtus sp. nov. Figs 1B , 4 , 5 , 15B , 16 Material examined. Holotype ♂ (ZMUM), Azerbaijan , NW above Bash-Layski ca. 20 km NNW of Sheki , 1250 m a.s.l. , Fagus , Carpinus , Acer , etc. forest, litter, 3.V.1987 , leg. S. Golovatch, K. Eskov. Paratypes : 5 ♂♂ , 3 ♀♀ (ZMUM), same collection data as holotype . Non-type material. Azerbaijan : 2 ♂♂, 6 ♀♀ (ZMUM), SW of Kuba, 750 m a.s.l., Fagus , Quercus , Carpinus , etc. forest, litter and under bark, 23.IV.1987, leg. S. Golovatch, K. Eskov; Russia, Dagestan : 1 ♂, 2 ♀♀ (ZMUM), Kurush, 2550 m a.s.l., S slope, subalpine and alpine meadows, 20.VIII.1990, leg. G. Magomedov. Diagnosis. Assigned to the genus Amblyiulus primarily because of the presence of a rod on the posterior gonopod opisthomere. Differs from A. georgicus , perhaps the most similar congener known to date, by the following combination of somatic and gonopodal characters. Head with frontal setae; collum and metazonae of body rings each with a posterior whorl of setae. Promere narrow, with two side ridges. Solenomere apically with small filament-like processes. Rod of opisthomere relatively long. Name. To emphasise the presence of metazonal setae; adjective. Description. Holotype : length 27 mm, width 1.3 mm, number of body rings 51+2+T. Paratypes: length 25-30 mm, width 1.2-1.4 mm, number of body rings in adults, 45-67+1-3+T (♂♂); or length 27-28 mm, width 1.1-1.3 mm, number of body rings, 46-55+2-3+T (♀♀). Body subcylindrical (typical of Julidae ), metazonae and prozonae yellowish grey (Fig. 1B ). Head, a few postcollum rings and telson slightly lighter than other body rings. Collum slightly more vividly reddish. Antennae, mouthparts, and legs yellow (Fig. 4A-C ). Eyes absent. Metazonae with weak, dense, and regular striations, 21-23 striae per quarter of metazonal surface, i.e., that between dorsal axial line and ozopore (Fig. 4A-G ). Ozopores relatively large, with a stria in front, lying behind suture without touching it (Fig. 4H ). Figure 4. Amblyiulus hirtus sp. nov., paratype ♂ from Bash-Layski, Azerbaijan (ZMUM) A-C anterior part of body, lateral, dorsal and ventral views, respectively D midbody part, lateral view E-G posterior part of body, lateral, dorsal and ventral views, respectively H ozopores on midbody rings, lateral view I gnathochilarium, ventral view J, K leg pair 1, lateral and caudal views, respectively L leg 2, caudal view M ventral edge of pleurotergum 7, lateral view. Scale bars: 0.5 mm ( A-G) or 0.1 mm ( H-M ). Antennae relatively long, in situ reaching ring 4. Head with 1+1 frontal, 8+8-9+9 labral and 2+2 supralabral setae (Fig. 4A-C ). Gnathochilarium with three thick setae on each lamella lingualis; stipites without setae in medial part, but with three long setae at anterolateral margin (Fig. 4I ). Collum and each following metazona with a whorl of setae at posterior margin (Fig. 4A ). Epiproct poorly developed, triangular, with several setae (Fig. 4E, F ). Hypoproct subtriangular, covered with long setae (Fig. 4G ). Telson and anal valves densely setose, setae being long. Male. Mandibular stipites unmodified (Fig. 4A ). Leg pair 1 small, unciform, with a group of setae on coxa and at base of telopodite; telopodites curved anteriad, not anteromesad as in other species of Julidae (Fig. 4J, K ). Leg pair 2 with a large pad on tibia and a small one on postfemur (Fig. 4L ). Penes short and bifurcate. Ventral edge of male pleurotergum 7 with small subtriangular lamellae bordering the gonopodal aperture (Fig. 4M ). Gonopods (Fig. 5 ) with anterior and posterior pair equal in height. Promere spoon-shaped, relatively narrow, constricted in basal third; with two ridges: mesal ridge prominent all along; lateral ridge short, located only in apical part of promere (Fig. 5B, H ). Mesomeral process simple, flattened, ribbon-shaped, with a small membranous lobe on top (Fig. 5A, C, G, I ). Opisthomere tripartite (Fig. 5A, C, E, F ). Solenomere long, slightly curved, with a caudomesal lamella notched apically; apical part with a fovea and short filament-like processes (Fig. 5A, C, G, I ). Solenomere sometimes with an additional filiform process apically (see Remarks under Syrioiulus taliscius ). Anterior process notched apically (Fig. 5A, C, E ). Rod of solenomere relatively long, consisting of filament-like structures, lateral in position (Fig. 5A, D-G, I ). Figure 5. Amblyiulus hirtus sp. nov., paratype ♂ from Bash-Layski, Azerbaijan (ZMUM) A, G gonopod, mesal and lateral views, respectively B, H promere, subcaudal and caudal views, respectively C, I posterior gonopod, lateral and mesal views, respectively D, E end of solenomere, mesal and submesal views, respectively F end of opisthomere, mesocaudal view. Abbreviations: ap anterior process cl caudomesal lamella ff filiform process fo fovea lr lateral ridge mr mesal ridge ms mesomeral process op opisthomere pr promere r rod sl solenomere. Scale bars: 0.1 mm ( A-C ); 0.01 mm ( D-F ); 0.2 mm ( G-I ). Female. First two leg pairs unmodified. Vulva rounded, operculum higher than bursa (Fig. 15B ) and bilobed apically. Bursa asymmetric, lateral valve higher than mesal one. Each valve with two rows of long setae. Median field of bursa very short, narrow; emargination of median field suboval. Remarks. This species seems to be endemic to the eastern part of the Caucasus Major within both northeastern Azerbaijan and the Republic of Dagestan, Russia (Fig. 16 ). It is the presence of a laterally positioned rod that brings both A. georgicus and A. hirtus sp. nov. particularly close together. However, the rod in these two species is located laterally, whereas that in A. barroisi anteromesally ( Enghoff 1992 : fig. 11; Golovatch 2018 : fig. 10C). These differences seem to be quite important, but because those three species share not only the presence of a rod, but also a small, but discernible fovea on top of the solenomere, for the time being it seems best to regard the trio as members of Amblyiulus .