Syrioiulus continentalis (Attems, 1903)

Figs 1D, 8A, B, 9, 10, 15D, 16

Pachyiulus (Dolichoiulus) continentalis Attems, 1903: 147, 148, figs 82-84 (D).

Amblyiulus continentalis - Lohmander 1932b: 40, 41, figs 33-35 (D); 1936: 156 (R); Rakhmanov 1971: 1412 (R); 1972: 116 (R); Samedov et al. 1972: 1245; Lokšina and Golovatch 1979: 385 (M); Bababekova 1996: 90 (M).

Syrioiulus continentalis - Mauriès 1982: 441 (M); 1984: 43 (M); Vagalinski 2020: 89 (M).

Material examined.

Azerbaijan: 3 ♂♂, 1 ♀ (ZMUM), Talysh Mts, Zuvand, Joni, 1500 m a.s.l., 28-29.V.1976, leg. V.G. Dolin ; 1 ♂ (ZMUM), Lenkoran, Hyrcan forest, Khan Bulan River near Alexeevka, 22.IV.1985, leg. E.B. Kupriyanova ; 7 ♂♂, 5 ♀♀, 2 juv. (ZMUM), Lenkoran, Hyrcan Nature Reserve, litter, 26.I.-4.II.1985, leg. A. Druk ; 2 ♂♂, 4 ♀♀ (ZMUM), same locality, 21.IX.1987, leg. S. Zonstein; 2 ♂♂, 2 juv. (IZB); 1 ♂, 1 ♀, 1 juv. (SMNG), Lǝnkǝran rayon, Hyrcan Nature Reserve, Daştatük 1.3 km Xanbulan Reservoir, Parrotia forest, diverse bushes, under leaves, 110 m a.s.l., 38.6747°N, 48.7622°E ; 1 ♂ (IZB); 1 ♂ (SMNG), same locality, SW of Asagi Apu, Quercus forest, within leaves and rotten wood, 180 m a.s.l., 38.6726°N, 48.7362°E, all leg. F. Walther, H. Reip, D. Antić; 3 ♂♂, 2 ♀♀, 1 juv. (IZB); 5 ♂♂, 3 ♀♀ (SMNG), Lerik rayon, Hyrcan Nature Reserve, road Lǝnkǝran-Lerik at km 32, small side valley, forest of Parrotia with some Quercus, thick leaf layer, 400 m a.s.l., 38.7638°N, 48.5819°E ; 1 juv. (IZB), Astara rayon, Hyrcan Nature Reserve, SW of Zünqülǝş, beginning of a small valley, Parrotia and Alnus bushes, in leaves, 60 m a.s.l., 38.4493°N, 48.7623°E ; 2 ♂♂, 1 juv. (IZB); 2 ♂♂, 1 ♀ (SMNG), same locality, end of small valley, steep slope, Parrotia, Quercus, Acer trees, under leaves and rotten tree trunks, 130 m a.s.l., 38.4480°N, 48.7597°E, all leg. F. Walther, H. Reip, D. Antić; 2 ♂♂ (ZMUM), Azfilial, 100 m a.s.l., 31.V.-1.VI.1996 ; 1 ♂ (ZMUM), Apo below Bilasar, 350 m a.s.l., 8-9.VI.1996 ; 2 ♂♂, 1 ♀, 1 juv. (ZMUM), Astara Distr., Istisu ca. 8 km WSW of Astara, Quercus, Acer, Carpinus, etc. forest, 10-30 m a.s.l., litter, under stones and bark, 10.X.1983 ; 2 ♀♀ (ZMUM), Istisu ca. 8 km SW of Masally, Quercus, Acer, Carpinus etc. forest, 80-140 m a.s.l., under bark and stones, 19-20.X.1983 ; 2 ♀♀ (ZMUM), Istisu W of Astara, 100 m a.s.l., 2-6.VI.1996, all leg. S. Golovatch.

Diagnosis.

Differs from all congeners by the following combination of somatic and gonopodal characters. Head with frontal setae. Collum and each metazona of following body rings with a whorl of long setae at caudal margin. Eyes present. Solenomere with a group of small spines on top. Anterior process of opisthomere subtriangular apically. This species is clearly distinguished in the field from all other millipedes by its characteristic greyish yellow colouration with a yellow stripe dorsally, and its particularly strong odour clearly resembling that of Pachyiulus krivolutskyi from the western Caucasus (= Colchis).

Redescription.

Length of adults 28-45 mm (♂♂) or 26-46 mm (♀♀), width 2.0-2.3 mm (♂♂) or 2.2-2.7 mm (♀♀). Number of body rings in adults, 46-66+1-2+T (♂♂) or 49-66+1-2+T (♀♀). Body subcylindrical, metazonae from greyish yellow to yellow, prozonae light yellow (Figs 1D, 8A, B); live specimens dorsally with a darker, vivid yellow stripe (Fig. 8B). Head, collum and telson slightly lighter than other body rings (Fig. 8A, B). Antennae grey, mouthparts and legs light yellow (Fig. 9A-G). Eyes present, black, oval, each composed of 19-23 ommatidia (Fig. 9A, C). Striations on metazonae deep, not reaching the caudal margin, 28-32 striae per quarter of metazonal surface, i.e., between dorsal axial line and ozopore (Fig. 9D). Ozopores large, lying behind suture without touching it (Fig. 9H).

Antennae relatively long, in situ reaching segment 3. Head with 1+1 frontal, 8+8-9+9 labral and 2+2-4+4 supralabral setae (Fig. 9A-C). Gnathochilarium with three long setae on each lamella lingualis, groups of several small setae in median part of stipites and six or seven long setae at anterolateral margin (Fig. 9I). Collum and each following metazona with a whorl of long and thick setae at posterior margin (Fig. 9A-F). Epiproct undeveloped (Fig. 9E, F). Hypoproct subtriangular, with long setae (Fig. 9G). Telson and anal valves densely setose, setae being long.

Male. Mandibular stipites expanded, with swollen lobes (Fig. 9A). Leg pair 1 small, unciform, telopodites directed anteromesad, with a group of long setae on each coxa; telopodite setose in basal part (Fig. 9J). Leg pair 2 with pads on postfemur and tibia (Fig. 9K). Penes short, bifurcate. Ventral edge of male pleurotergum 7 with narrow elongated lamellae bordering the gonopodal aperture (Fig. 9L).

Gonopods (Fig. 10) with anterior (promere) part higher than posterior (opisthomere) one. Promere spoon-shaped, constricted in basal third; mesal ridge wide along 2/3 extent; with denticles in apical part: mesal denticle small and broadly rounded, lateral one well-expressed and long (Fig. 10B, E). Mesomeral process simple, slightly curved, flattened apically (Fig. 10A, C, F). Opisthomere bipartite (Fig. 10D). Solenomere elongated, with an apical membranous lobe, subtriangular at apex, with a fovea and a group of small spines on top; caudomesal lamella wide (Fig. 10A, C, D, F). Anterior process of opisthomere subtriangular apically (Fig. 10D).

Female. First two leg pairs unmodified. Operculum of vulva without setae on caudal surface, apical margin relatively flat (Fig. 15D). Bursa subsymmetrical, lateral valve slightly larger than mesal one. Each valve with two rows of long setae. Median field of bursa narrow; emargination of median field suboval.

Remarks.

Probably one of the most common and apparently the largest species of the genus. The unusually strong odour and the chemical composition of the repugnatorial secretion are similar to those of Pachyiulus krivolutskyi (Makarov et al., pers. obs.). This species inhabits various deciduous forests in Azerbaijan, also occurring in northern Iran (Lohmander 1932b), endemic to the Hyrcanian biogeographic province (Fig. 16).