Research in domain of droplet impingement erosion of the power equipment: lookback study and context analysis

The main work objective is the creation of the scientific background for correct determination of a set of requirements to the fabrication material with a high-wearing feature under the droplet impingement erosion. A review of a backward and present state of the art of the national and foreign investigations in the field of the droplet impingement erosion of metal materials is carried out. The main outcome is as follows: insufficient fundamentality of research in this area; limitation of the used theoretical models; one-sided approach of many authors to the phenomenon that combines a whole set of factors of different physical nature. On this background, the author's concept of the erosive wear process of metal under the influence of two-phase mist flow is presented. Particular attention is paid to a new scientific hypothesis of the active hydrogen effect on the fracture of metal under the hypervelocity dropwise collisions

Micropachyiulus pygmaeus

<i>Micropachyiulus pygmaeus</i> (Attems, 1904) <p> <i>Pachyiulus (Hylopachyiulus) pygmaeus</i> Attems, 1904: 183–184, figs 23, 24</p> <p> <i>Micropachyiulus pygmaens</i> (sic!): Verhoeff (1907: 460)</p> <p> <i>Micropachyiulus (Micropachyiulus) pygmaeus</i>: Verhoeff (1907: 461)</p> <p> <i>Hylopachyiulus pygmaeus</i>: Attems (1926a: 258); Antić <i>et al.</i> (2018: 234, figs 6–8E, F)</p> <p> <i>Hylopachyiulus corylorum</i>: Strasser (1966: 44) (synonymization)</p> <p> <i>Hylopachyiulus likanus</i>: Strasser (1966: 44) (synonymization)</p> <p> <b>Diagnosis.</b> A species of <i>Micropachyiulus</i> without ommatidia. Differs from all congeners by a relatively welldifferentiated mesomeral process being clearly divided from the opisthomere in its distal half, vs. the mesomeral process being mostly fused to the opisthomere, with only a small freely protruding apical part in the remaining species.</p> <p> Otherwise very similar to <i>Micropachyiulus corylorum</i>, <i>Micropachyiulus ocellatus</i> <b>comb. nov.</b> and <i>Micropachyiulus paucioculatus</i> in terms of gonopod conformation, and especially in the shape of the solenomere which ends up with a minute, transversely oriented apical projection. Differs easily from <i>M. ocellatus</i> <b>comb. nov.</b> by a long and pointed (vs. short and blunt) epiproct, and from <i>M. paucioculatus</i> —by a much shorter solenomere (subequal to tip of mesomeral process and apical margin of posterior lamella, vs. considerably overreaching both of them). Differs from <i>M. corylorum</i>, by a slender and straight (vs. stout and bent ventrad) epiproct and by details of the opisthomere: absence of a rod-like process next to the solenomere and solenomere and mesomeral process subequal in height (vs. solenomere considerably overreaching tip of mesomeral process).</p> <p> <b>Distribution</b> (Fig. 14, cyan circle). <b>Bosnia and Herzegovina:</b> Banja Luka (type locality).</p>Published as part of <i>Vagalinski, Boyan, Evsyukov, Aleksandr P., Chumachenko, Yuri A. & Zabiyaka, Igor Y., 2023, A review of the genus Micropachyiulus Verhoeff, 1899 and description of the related Armeniopachyiulus gen. nov. (Diplopoda: Julida: Julidae: Pachyiulini), pp. 221-246 in Zootaxa 5239 (2)</i> on page 231, DOI: 10.11646/zootaxa.5239.2.3, <a href="http://zenodo.org/record/7624205">http://zenodo.org/record/7624205</a&gt

Micropachyiulus corylorum Verhoeff 1908

<i>Micropachyiulus corylorum</i> Verhoeff, 1908 <p>Fig. 2</p> <p> <i>Micropachyiulus corylorum</i> Verhoeff, 1908 (in Verhoeff 1907 (for 1908)): 459–460, figs 21, 22</p> <p> <i>Hylopachyiulus corylorum</i>: Attems (1926a: 258); Attems (1926b: 245); Antić <i>et al.</i> (2018: 227–231, figs 1–3, 8A, B) <i>Hylopachyiulus likanus</i> Attems, 1926 (in Attems 1926b): 244–245, figs 339–341 (synonymized by Antić <i>et al.</i> 2018)</p> <p> <i>Hylopachyiulus pygmaeus</i>: Strasser (1966: 44) (synonymization)</p> <p> <b>Material examined.</b> 1 ♂, 3 ♀♀ (SMNG), Croatia, Rijeka, Velika Kapela Mts, Delnice, Mrkopalj Valley, W of Sunger, 45.3321°N, 14.8110°E, 780 m a.s.l., <i>Corylus - Acer</i> stand, in litter, 15.X.2010, H. Reip leg.; 1 ♂ (SMNG), same locality, 45.3324°N, 14.8107°E, 790 m a.s.l., young <i>Picea</i> forest, in litter, same date and collector; 1 ♂, 4 ♀♀, 1 juv. (IBER), Croatia, Rijeka, Velika Kapela Mts, Lič, Rudine locality, 45.2631°N, 14.7572°E, 750 m a.s.l., open grassy area with small bushes of <i>Juniperus</i> and <i>Corylus</i>, among <i>Corylus</i> litter, sifting, 14.X.2010, H. Reip leg.; 2 ♂♂ (SMNG), Slovenia, Ilirska Bistrica, Snežnik, Sviščaki mountain area, 45.5677°N, 14.3735°E, 1300 m a.s.l., at the edge of a forested ravine, mostly <i>Fagus</i>, in litter, 11.X.2010, H. Reip leg.</p> <p> <b>Diagnosis.</b> A species of <i>Micropachyiulus</i> without ommatidia. Very similar to <i>Micropachyiulus ocellatus</i> <b>comb. nov.</b>, <i>Micropachyiulus paucioculatus</i> and <i>Micropachyiulus pygmaeus</i> in terms of gonopod conformation, and especially in the shape of the solenomere which ends up with a minute, transversely oriented apical projection.Differs from all these species by the presence of an opisthomeral rod-like process just behind the solenomere. Differs further from <i>M. pygmaeus</i> by a stouter (vs. slender) epiproct bent ventrad (vs. straight) and by the solenomere considerably overreaching tip of mesomeral process, vs. the solenomere being subequal to tip of mesomeral process; from <i>M. paucioculatus</i> by a much shorter solenomere and by the apical outgrowth of the mesomeral process deviating anteriad rather than running parallel to the main axis of the opisthomere; and from <i>M. ocellatus</i> <b>comb. nov.</b> by a much longer epiproct.</p> <p> <b>Descriptive notes.</b> Legs 1 in males each with a verrucose hump baso-mesally on the distal podomere.</p> <p> Gonopods (Fig. 2): Promere (Fig. 2D, <i>P</i> in Fig. 2A) somewhat higher than opisthomere, relatively elongate, with nearly straight or gently sigmoid mesal margin and an abruptly sigmoid lateral one, the two joining in a nearly right-angled meso-apical corner; mesal (<i>mr</i>) and lateral (<i>lr</i>) ridges short but well-pronounced, distal ridge (<i>dr</i>) long but rather weakly protruding, with just a few minute spines at proximal part; median groove (<i>mg</i>) relatively broad and not too deep. Opisthomere (Fig. 2B, C, E, F and <i>O</i> in 2A) slender, very gently sigmoid in mesal and lateral views (distally bent slightly anteriad); mesomeral process (<i>m</i>) relatively well-pronounced, lamellar, completely undivided from the opisthomere, except for a small, tapering outgrowth (<i>mp</i>) bent more or less posteriad; posterior lamella (<i>l</i>) moderately pronounced, slightly wrinkled, apically forming a fimbriate margin (<i>fr</i>) protruding behind the solenomere; without setiform filaments on mesal surface; solenomere (<i>s</i>) very slender, rod-like, with a T-shaped tip, i.e. with a small apical projection (<i>sp</i>) set transversely to the main axis of solenomere; an additional rod-like process (<i>r</i>) present just behind the solenomere, being slightly shorter than the latter.</p> <p> The examined males from Croatia (also taking in consideration the gonopod figures in Antić <i>et al.</i> 2018, based on material from the same country) and Slovenia show some moderate, most likely intraspecific differences: Outgrowth of mesomeral process more gradually bent posteriad and apically smooth in the Croatian specimens, vs. same being abruptly bent posteriad and apically shortly branched in the Slovenian ones; and promere more slender, markedly sigmoid in anterior and posterior views, narrowing all the way to the apex in the Croatian specimens, vs. same being stouter, with mostly straight and parallel side margins in the Slovenian ones.</p> <p> <b>Distribution</b> (Fig. 14, ochre circles). <b>Slovenia:</b> Jesenice (type locality), near Ribnica (Antić <i>et al.</i> 2018), Snežnik (Antić <i>et al.</i> 2018, present study); <b>Italy:</b> Friuli –Venezia Giulia: near Ragogna (Antić <i>et al.</i> 2018); <b>Croatia:</b> Velebit Mtn: Štirovača (type locality of <i>Hylopachyiulus likanus</i>); other localities in Velebit Mtn (Antić <i>et al.</i> 2018); Velika Kapela Mts (present study).</p>Published as part of <i>Vagalinski, Boyan, Evsyukov, Aleksandr P., Chumachenko, Yuri A. & Zabiyaka, Igor Y., 2023, A review of the genus Micropachyiulus Verhoeff, 1899 and description of the related Armeniopachyiulus gen. nov. (Diplopoda: Julida: Julidae: Pachyiulini), pp. 221-246 in Zootaxa 5239 (2)</i> on pages 225-227, DOI: 10.11646/zootaxa.5239.2.3, <a href="http://zenodo.org/record/7624205">http://zenodo.org/record/7624205</a&gt

Armeniopachyiulus Vagalinski & Evsyukov & Chumachenko & Zabiyaka 2023, gen. nov.

<i>Armeniopachyiulus</i> gen. nov. <p> <b>Type species.</b> <i>Armeniopachyiulus pokr</i> <b>gen.</b> <i>et</i> <b>sp. nov.</b> <b>, by present designation</b></p> Included species. <p>The new genus is monospecific.</p> <p> <b>Diagnosis.</b> A genus of the tribe Pachyiulini being most similar to <i>Micropachyiulus</i> in both external and gonopod morphology: Body very small (L typically less than 13 mm, H less than 0.8 mm); with vertigial and metazonal setae; pre-anal ring with an epiproct; mandibular stipites in males not expanded; promere with a rather short mesal ridge and an elongated, microdentate/spinulate, distal ridge; opisthomere with a well-developed posterior lamella and a rather weakly differentiated mesomeral process. Differs from <i>Micropachyiulus</i> mainly by the structure of the opisthomere which lacks a distinct solenomeral process, but possesses an apical fovea, while it possesses a slender solenomeral process apically, but lacks apical fovea in the latter genus.</p> <p> <b>Etymology.</b> Derived from Armenia, the <i>terra typica</i>, and <i>Pachyiulus</i>, the type genus of the tribe Pachyiulini. Masculine.</p>Published as part of <i>Vagalinski, Boyan, Evsyukov, Aleksandr P., Chumachenko, Yuri A. & Zabiyaka, Igor Y., 2023, A review of the genus Micropachyiulus Verhoeff, 1899 and description of the related Armeniopachyiulus gen. nov. (Diplopoda: Julida: Julidae: Pachyiulini), pp. 221-246 in Zootaxa 5239 (2)</i> on pages 239-240, DOI: 10.11646/zootaxa.5239.2.3, <a href="http://zenodo.org/record/7624205">http://zenodo.org/record/7624205</a&gt

Micropachyiulus caucasicus Vagalinski & Evsyukov & Chumachenko & Zabiyaka 2023, sp. nov.

Micropachyiulus caucasicus sp. nov. Figs 1D, E, 5–7 Material examined (ZMUM). Holotype: ♂, Russia, Krasnodar Province, Khosta, Caucasian Nature Reserve, Taxus & Buxus grove, soil (0–15 cm), 25.III.2016, Y. Chumachenko leg. Paratypes: 5 ♂♂ (two unbroken, three in 2 or more pieces; head, leg-pair 1 and gonopods of one prepared for SEM; head, gonopods and most of body of another prepared for SEM), 9 ♀♀ (7 unbroken, one in 3 pieces, another in 2 pieces, both with dissected vulvae), same collecting data as for holotype. Diagnosis. A species of Micropachyiulus with ommatidia. Most similar to Micropachyiulus filiformis sp. nov., both being characterized by a very long and thin solenomere of the opisthomere, without apical bulge or projection, a minute, spike-like outgrowth of the mesomeral process, and an opisthomeral posterior lamella expanding in a mesal ridge partly concealing the distal section of the sperm channel. Differs from M. filiformis sp. nov. by a bulging vs. flat anterior surface of the opisthomere, by the posterior lamella being smooth vs. overgrown with setiform filaments, by the promere gradually narrowing towards apex, vs. abruptly constricting in the middle, by the longer and more roughly serrated distal ridge of the latter, as well as by the shape of male legs 1: without tarsal remnants vs. the latter present as micropapillate bulges, and with slender vs. broad, flattened tibial outgrowths. Also resembles M. paucioculatus by the very long solenomere of the opisthomere, but differs clearly from it by the solenomere lacking an apical bulge or projection and by the minute, spike-like (vs. well-developed, slender) outgrowth of the mesomeral process. Etymology. After its provenance from the Caucasus region. Adjective. Description. Measurements: Holotype with BRF 40 + 1 + T, L = 7 mm, H = 0.55 mm; paratype ♂♂ with BRF 35–39 + 1–2 + T, L = 6–7 mm, H = 0.47–0.5 mm; paratype ♀♀ with BRF 33–42 + 1–3 + T, L = 5–9 mm, H = 0.5–0.52 mm. Colouration (after several years in ethanol) (Fig. 1D, E): mostly yellowish-beige, prozonae dorso-laterally light brown. Head (Fig. 5B): With 3–5 pigmented ommatidia arranged in one or two rows on each side. Vertigial, supralabral and labral setae: 2, 4 and 13–14, respectively. Antennae (Fig. 5A) 1.5 times as long as head in males and 1.4 times in females; antennomere 5 ≥ 2> 4> 3> 6; 5 ca 1.5 times as long as broad and ca 1.6 times as broad as 2; size and distribution of sensilla as in M. paucioculatus. Mandibular stipites in males not expanded. Labrum tridentate. Gnathochilarium with 3 long distal setae on each stipes, proximal parts completely non-setose, stipital palps as in M. paucioculatus; promentum rather small, separating lamellae linguales in ca their proximal 1/3, the latter each bearing three more or less equally spaced setae in a row. Trunk and legs: Collum completely smooth. Body rings (Fig. 5C) insignificantly vaulted. Prozonae completely smooth, except for their anteriormost sections (normally covered by the preceding ring’s metazona) having finely reticulated texture. Metazonae shallowly and rather sparsely striated, striation becoming deeper and denser ventrally, dorsally and laterally not crossing entire length of metazona; metazonal setae rather short, mostly fallen off. Ozopores (oz in Fig. 5C) set tightly behind pro-metazonal suture in more anterior rings, and somewhat further back (up to 2 x their diameter) in more posterior rings. Walking legs relatively short: ML ca 0.7 times as long as H in males and 0.6 times in females. Tarsus of ML ca 1.5 times as long as tibia and ca 2.3 times as long as apical claw. Accessory claws absent from all legs in both sexes. Telson: Pre-anal ring sparsely but evenly covered with long setae. Epiproct relatively long (nearly reaching level of tip of longest paraproctal setae), straight to slightly bent ventrad, wedge-like, ending with a fine, sharply pointed hyaline tip (often broken off). Hypoproct of same shape as in M. paucioculatus; ventrally with two submarginal setae. Pilosity on paraprocts of moderate density, without distinct row of shorter setae along posterior margins. Male sexual characters: Legs 1 (Fig. 5D) 3-segmented hooks oriented (almost) completely mesad, and (sometimes) slightly anteriad; tibial outgrowth rather slender, tarsal remnant indistinct or absent; the distal podomere baso-mesally with a verrucose hump (h). Leg-pair 2 (Fig. 7A) considerably ticker and slightly longer than following legs. Ventral adhesive pads altogether absent. Flanges of pleurotergum 7 (Fig. 7C) ventrally forming rather narrow shovel-like lobes originating at the border zone between pro- and metazona, directed ventro-mesad. Gonopods (Figs 6, 7D) in situ mostly concealed in gonopodal sinus. Promere (Fig. 6B and P in Figs 6A, D, 7D) relatively slender, slightly overreaching opisthomere, gently sigmoid in anterior or posterior views, gradually narrowing towards a rounded apex directed somewhat mesad; mesal ridge (mr) well-developed, roughly pyramidal, with a pointed tip, mesally bearing several very short setiform filaments; lateral ridge (lr) short and rather weakly pronounced; distal ridge (dr) large and strongly pronounced, marginally densely denticulate; median groove indistinct. Opisthomere (Fig. 6C, E, and O in Figs 6A, D, 7D) stouter than in M. paucioculatus, very slightly sigmoid in lateral and mesal views, antero-basally somewhat bulging; mesomeral process (m) weakly pronounced, lamellar, completely undivided from the opisthomere, apically forming a minute spike-like outgrowth (mp) directed anteriad or baso-anteriad; posterior lamella (l) well-developed, expanding in a large mesal crest concealing distal section of sperm channel (sc); setiform filaments absent; solenomere (s) long and very fine, thread-like/flagelliform. Female sexual characters: Leg-pairs 1 (significantly) and 2 (slightly) ticker and somewhat shorter than following pairs. Vulva (Fig. 7E) stout, somewhat compressed on sides, roughly conical in side view; median field (mf) deeply concave, elongate, extending proximally to almost mid-height of bursa; operculum (op) higher than bursa, broad, with a concave apical margin, apical corners extended into hyaline protrusions, mesal one larger than lateral one; two smaller and tapering protrusions present apically on bursa; each bursal valve bearing two distal setae, operculum non-setose. RS composed of a narrow, somewhat folded central tube (ct) ending in an ovoid central ampulla (ca), and a posterior tube (pt) of similar length and gauge as the central tube, ending in a piriform posterior ampulla (pa) of similar size as the central one. Distribution (Fig. 14, purple circle). Russia: Krasnodar Province: Caucasian Nature Reserve (type locality).Published as part of Vagalinski, Boyan, Evsyukov, Aleksandr P., Chumachenko, Yuri A. & Zabiyaka, Igor Y., 2023, A review of the genus Micropachyiulus Verhoeff, 1899 and description of the related Armeniopachyiulus gen. nov. (Diplopoda: Julida: Julidae: Pachyiulini), pp. 221-246 in Zootaxa 5239 (2) on pages 231-235, DOI: 10.11646/zootaxa.5239.2.3, http://zenodo.org/record/762420

Micropachyiulus paucioculatus

<i>Micropachyiulus paucioculatus</i> (Verhoeff, 1899) <p>Figs 1A, 3, 4</p> <p> <i>Pachyiulus (Micropachyiulus) paucioculatus</i> Verhoeff, 1899: 184–185, figs 1–4</p> <p> <i>Pachyiulus (Micropachyiulus) paucioculatus</i>: Verhoeff (1900: 211)</p> <p> <i>Pachyiulus paucioculatus</i>: Verhoeff (1900: 220)</p> <p> <i>Micropachyiulus paucioculatus</i>: Verhoeff (1907: 460); Attems (1926a: 259); Kime & Enghoff (2017: 133); Giurginca (2021: 200–201, fig. 156)</p> <p> <i>Micropachyiulus pauciocalatus</i> (sic!): Verhoeff (1907: 461)</p> <p> <i>Micropachyiulus pauciocellatus</i> (sic!): Kime & Enghoff (2017: 270)</p> <p> <b>Material examined.</b> <b>Syntypes</b> (MNB): <i>Pachyiulus paucioculatus</i> Verhoeff, Valea Corbului, slide preparations 1138–1140: antennae, legs, gonopods, mouthparts, flanges of male pleurotergum 7. <b>Other material</b>: 3 ♂♂, 3 (supposedly) adult ♀♀, 1 frontal part of an (supposedly) adult ♀, 1 (supposedly) subadult ♀ (IBER), Romania, Oltenia, Motru Sec, Cloşani, slope at roadside, 45.0809°N, 22.8014°E, 400 m a.s.l., mostly <i>Fagus</i>, in and under leaf litter in a mixture of soil and fine gravel, 30.X.2021, H. Reip, K. Voigtländer, D. Antić, D. Stojanović, and B. Vagalinski leg.; 2 ♂♂, 2 (supposedly) adult ♀♀ (NHMW MY 10327), same collecting data.</p> <p> <b>Diagnosis.</b> A species of <i>Micropachyiulus</i> with ommatidia, being very similar to <i>Micropachyiulus corylorum</i>, <i>Micropachyiulus ocellatus</i> <b>comb. nov.</b> and <i>Micropachyiulus pygmaeus</i> in terms of gonopod conformation, and especially in the shape of the solenomere which ends up with a minute, transversely oriented apical projection. Differs from all these species by a much longer solenomere (considerably overreaching the apical part of the posterior lamella, vs. being subequal to it) and an apically smooth rather than serrate or fimbriate posterior lamella. Differs further from <i>M. corylorum</i> by the absence of an opisthomeral rod-like process just behind the solenomere; from <i>M. ocellatus</i> <b>comb. nov.</b> by a more slender apical outgrowth of the mesomeral process, running mostly parallel to the main axis of the opisthomere rather than deviating anteriad; and from <i>M. pygmaeus</i> by a long and pointed (vs. very short and blunt) epiproct and a more slender promere.</p> <p> Also resembles <i>M. caucasicus</i> <b>sp. nov.</b> and <i>M. filiformis</i> <b>sp. nov.</b> by the very long solenomere, but differs clearly from both of them by the solenomere lacking an apical bulge or projection and by the well-developed, slender (vs. minute, spike-like) outgrowth of the mesomeral process.</p> <p> <b>Redescription.</b> Measurements: ♂♂ with BRF 31–39 + 3 + T, L = 6–8.2 mm, H = 0.41–0.50 mm; ♀♀ with BRF 34–43 + 2–3 + T, L = 8.3–9.7 mm, H = 0.53–0.69 mm.</p> <p>Colouration (Fig. 1A): light beige to brownish, living specimens with purple tinges, gut and the reddish repugnatorial glands partly visible by transparency.</p> <p>Head (Fig. 3A): With 1–4 pigmented ommatidia arranged in one or two rows on each side. Vertigial, supralabral and labral setae: 2, 4 and 13–14, respectively. Antennae 1.4–1.55 times as long as head in males and 1.2–1.3 times in females; antennomere 5 ≥ 2 ≥ 3 = 4> 6; 5 1.5–1.6 times as long as broad and ca 1.7 times as broad as 2; 5 and 6 with a row of several sensilla basiconica dorsally and laterally at distal margins, those on 5 of slightly larger than the four apical sensilla, those on 6 considerably smaller. Mandibular stipites in males not expanded. Labrum tridentate. Gnathochilarium with 3 long distal setae and a short medial one on each stipes, stipital palps relatively small, each bearing several minute apical sensilla; promentum medium-sized, separating lamellae linguales in ca their proximal 2/5, the latter each bearing three more or less equally spaced setae in a row.</p> <p>Trunk and legs: Collum completely smooth. Body rings slightly to moderately vaulted. Prozonae mostly smooth, with some very short and shallow striae next to suture. Metazonae with shallow and rather sparse parallel striae, mostly crossing entire length of metazona; metazonal margins with a rather dense whorl of erect to slightly slanting setae, those on anterior and mid-body rings ca 0.25 times as long as H in males, ca 0.18 in females, those on posterior rings ca 0.33 and 0.23 times in males and females, respectively. Ozopores set tightly behind pro-metazonal suture in most rings, and slightly further back (up to 1.5x their diameter) in posterior-most rings. Walking legs relatively short: ML 0.65–0.7 times as long as H in males and 0.55–0.65 times in females. Tarsus of ML ca 1.8 times as long as tibia and ca 2.6 times as long as apical claw. Male legs 2 (Fig. 4B) with a short accessory claw, next pairs without; a similarly developed accessory claw in female legs 1 and 2, next pairs without.</p> <p>Telson: Pre-anal ring evenly and rather densely covered with long setae. Epiproct rather long (reaching level of tip of longest paraproctal setae), proximally straight, wedge-like, distally extending in a very slender, pointed, hyaline tip directed more or less ventrad. Hypoproct small, broadly rounded, tightly adhering under paraprocts in both sexes; ventrally with a pair of submarginal setae. Paraprocts moderately densely setose, without distinct row of shorter setae along posterior margins.</p> <p> Male sexual characters: Leg-pair 1 (Figs 3B, 4A) 3-segmented hooks oriented (almost) completely mesad, and (sometimes) very slightly anteriad; tibial outgrowth rather slender and tapering, tarsal remnant usually present as a minute spike; the distal podomere baso-mesally with a verrucose hump (<i>h</i>). Leg-pair 2 (Fig. 4B) visibly longer and ticker than following legs. Ventral adhesive pads altogether absent. Flanges of pleurotergum 7 (Fig. 4C) ventrally forming broad, rounded lobes originating at the border zone between pro- and metazona, directed mostly mesad.</p> <p> Gonopods (Figs 3C–E, 4D) <i>in situ</i> mostly concealed in gonopodal sinus, only tips of promeres visible on the outside, pro- and opisthomere (with tip of solenomere) subequal in height. Promere (Fig. 3C and <i>P</i> in Fig. 4D) slender, sigmoid in mesal and lateral views, gradually narrowing towards a broadly rounded or flattened apex; posterior surface with a short and weakly pronounced mesal ridge (<i>mr</i>), a similarly developed lateral ridge (<i>lr</i>), and a rather small, oblique, distal ridge (<i>dr</i>) bearing about a dozen small denticles, with some being present also basally to the ridge; a very deep and narrow median groove (<i>mg</i>) between mesal and lateral ridges. Opisthomere (Fig. 3D, E and <i>O</i> in Fig. 4D) relatively slender, gently sigmoid in mesal and lateral views (distally bent anteriad); mesomeral process (<i>m</i>) weakly pronounced, lamellar, ending with a small blunt outgrowth (<i>mp</i>) directed distad; posterior lamella (<i>l</i>) well-developed, expanding into a mesal crest apically forming a minute tapering outgrowth; mesal surface with numerous setiform filaments (<i>sf</i>) between posterior lamella and sperm channel (<i>sc</i>); solenomere (<i>s</i>) in the shape of a long and thin rod with a small apical projection (<i>sp</i>) set transversely to main axis of solenomere.</p> <p> Female sexual characters: Leg-pairs 1 and 2 slightly ticker and shorter than following pairs. Vulva (Fig. 4E) subconical, stout, somewhat compressed on sides; median cleft positioned sub-apically, surrounded by a small and shallow median field; operculum (<i>op</i>) significantly higher than bursa, apically strongly concave, ending up with a large, rounded hyaline protrusion on each side; two smaller and tapering protrusions present apically on bursa; each bursal valve bearing two setae, operculum non-setose. RS composed of a rather long digitiform central tube (<i>ct</i>), only slightly widening towards bottom rather than forming a distinct ampulla; and a long and narrow, folded, posterior tube (<i>pt</i>) ending in an ovoid posterior ampulla (<i>pa</i>).</p> <p> <b>Distribution</b> (Fig. 14, green circles). <b>Romania:</b> South Carpathians: Mehedinți Mts: CloȘani karst area (Giurginca 2021, present study); Şureanu Mts: near Bolii Cave, Corbului Valley near Pui (original localities).</p> <p> <b>Remark.</b> This species is probably a troglophile, as it shows preference for limestone areas where it has been found in both caves and external habitats (Kime & Enghoff 2017).</p>Published as part of <i>Vagalinski, Boyan, Evsyukov, Aleksandr P., Chumachenko, Yuri A. & Zabiyaka, Igor Y., 2023, A review of the genus Micropachyiulus Verhoeff, 1899 and description of the related Armeniopachyiulus gen. nov. (Diplopoda: Julida: Julidae: Pachyiulini), pp. 221-246 in Zootaxa 5239 (2)</i> on pages 228-231, DOI: 10.11646/zootaxa.5239.2.3, <a href="http://zenodo.org/record/7624205">http://zenodo.org/record/7624205</a&gt

Micropachyiulus filiformis Vagalinski & Evsyukov & Chumachenko & Zabiyaka 2023, sp. nov.

<i>Micropachyiulus filiformis</i> sp. nov. <p>Figs 1B, C, 8–10</p> <p> <b>Material examined</b>. <b>Holotype:</b> ♂ (in 2 pieces, gonopods in microtube) (NMNHS), Romania, Oltenia, Râmnicu Vâlcea, Căpătânii Mts, Mt Stogu, 45.2754°N, 24.1330°E, 1080 m a.s.l., <i>Corylus</i>, <i>Fagus</i>, <i>Acer pseudoplatanus</i>, <i>Fraxinus</i>, <i>Abies</i>, <i>Parietaria</i> etc., in thick leaf litter, 01.XI.2021, H. Reip, K. Voigtländer, D. Antić, D. Stojanović, and B. Vagalinski leg.</p> <p> <b>Paratypes:</b> 1 ♂ (in 4 pieces, head plus collum, leg-pair 1 and gonopods prepared for SEM, leg pair 2, right leg 3, and right flange of pleurotergum 7 in microtube), 4 (supposedly) adult ♀♀ (one in two pieces with left vulva in microtube, the others unbroken), 1 subadult female (in head plus collum and rest of body) (NMNHS), same collecting data as for holotype; 1 ♂ (unbroken), 2 ♀♀ (unbroken) (NHMW MY 10326), same data as for holotype.</p> <p> <b>Diagnosis.</b> A species of <i>Micropachyiulus</i> with ommatidia. Most similar to <i>Micropachyiulus caucasicus</i> <b>sp. nov.</b>, both being characterized by a very long and thin solenomere of the opisthomere, without apical bulge or projection, a minute, spike-like outgrowth of the mesomeral process, and an opisthomeral posterior lamella expanding in a mesal ridge partly concealing the distal section of the sperm channel.</p> <p> Differs from <i>M. caucasicus</i> <b>sp. nov.</b> by a flat vs. bulging anterior surface of the opisthomere, by the posterior lamella being overgrown with seti-/spiniform filaments, vs. same being smooth, by the promere being abruptly constricted in the middle, vs. same gradually narrowing towards apex, by the shorter and more finely serrated distal ridge of the latter, as well as by the shape of male leg-pair 1: tarsal remnants present as micropapillate bulges, vs. the latter absent, and with broad and flattened vs. slender tibial outgrowths.</p> <p> Also resembles <i>M. paucioculatus</i> by the very long solenomere of the opisthomere, but differs clearly from it by the solenomere lacking an apical bulge or projection and by the minute, spike-like (vs. well-developed, slender) outgrowth of the mesomeral process.</p> <p> <b>Etymology.</b> Meaning ‘thread-like’ in Latin, after the long and very fine solenomere, characteristic of this new species. Adjective.</p> <p> <b>Description.</b> Measurements: holotype with BRF 44 + 2 + T, L = 8.6 mm, H = 0.5 mm; paratype ♂♂ with BRF 38 + 3 + T, L = 6.7 mm, H = 0.45 mm, and BRF 46 + 1 + T, H = 0.53 mm, L impossible to be accurately measured due to the strongly coiled body; paratype ♀♀ with BRF 36–48 + 1–3 + T, L = 8.3–10.6 mm, H = 0.58–0.65 mm.</p> <p>Colouration: Beige to brown in ethanol; living specimens (Fig. 1B, C) whitish to very light grey-beige; the gut partly visible by transparency, the orange to light red repugnatorial glands clearly visible under the cuticle.</p> <p> Head (Fig. 8A): With 2–5 pigmented ommatidia arranged in one or two rows on each side. Vertigial, supralabral and labral setae: 2, 4 and 13–16, respectively. Antennae (Fig. 8B) ca 1.35 times as long as head in males and ca 1.25 times in females; antennomere 5 ≥ 2> 4 ≥ 3> 6; 5 ca 1.6 times as long as broad and 1.8–9 times as broad as 2; sensilla basiconica of similar conformation as in <i>M. paucioculatus</i>, but with a denser whorl of better developed sensilla on antenomere 7. Mandibular stipites in males not expanded. Labrum tridentate. Gnathochilarium with 3 (usually) or 4 (in some specimens) distal setae and with a very short medial seta on each stipes; stipital palps as in <i>M. paucioculatus</i>; promentum as in <i>M. paucioculatus</i>, but setae on lingual lamella clearly grouped in 2 proximal and 1 distal seta rather than nearly equally spaced.</p> <p>Trunk and legs: Walking legs (Fig. 10A, B) relatively short: ML 0.65–0.7 times as long as H in males and 0.45–0.55 times in females. Tarsus of ML ca 1.3–1.45 times as long as tibia and ca 2–2.5 times as long as apical claw. Accessory claws absent from all legs in both sexes.</p> <p> Telson: Pre-anal ring evenly and rather densely setose. Epiproct long (usually somewhat exceeding, rarely reaching level of tip of longest paraproctal setae), gradually bent ventrad, ending with a pointed hyaline tip. Other trunk and leg characters as in <i>M. paucioculatus</i>.</p> <p> Male sexual characters: Leg-pair 1 (Fig. 8C, D) 3-segmented hooks oriented mostly mesad and slightly anteriad; tibial outgrowth rounded, dorso-ventrally flattened, tarsal remnant present as a massive, micropapillate bulge; the distal podomere with a verrucose hump (<i>h</i>) basally on mesal side. Legs 2 (Fig. 10A) slightly thicker and ca as thick as following legs. Ventral adhesive pads altogether absent. Flanges of pleurotergum 7 (Fig. 10C) ventrally forming rather narrow, rounded lobes originating at the border zone between pro- and metazona, directed ventro-mesad.</p> <p> Gonopods (Figs 9, 10D) <i>in situ</i> mostly concealed in gonopodal sinus. Promere (Fig. 9B, C and <i>P</i> in Figs 9A, 10D) slender, somewhat overreaching opisthomere, similar in shape to that in <i>M. paucioculatus</i>, but more spoonshaped, i.e. lateral margin sharply incised in the middle, then going gradually convex until the narrowly rounded apex; mesal (<i>mr</i>) and lateral (<i>lr</i>) ridges short and rather weakly pronounced, distal ridge (<i>dr</i>) well-pronounced, marginally finely serrated; a rather shallow median groove (<i>mg</i>) between mesal and lateral ridges. Opisthomere (Fig. 9D–F and <i>O</i> in Figs 9A, 10D) relatively slender, but somewhat stouter than in <i>M. paucioculatus</i>, more or less straight rather than sigmoid in lateral or mesal view; mesomeral process (<i>m</i>) completely vestigial, present as a weakly pronounced lamella, distally forming a minute, pointed outgrowth (<i>mp</i>) directed anteriad; posterior lamella (<i>l</i>) well-developed, expanding in a mesal crest concealing apical section of sperm channel (<i>sc</i>); its mesal side and the area between the lamella and the sperm channel with numerous setiform filaments (<i>sf</i>), these being much shorter than in <i>M. paucioculatus</i>; solenomere (<i>s</i>) very long and fine, thread-like, more or less bent or coiled anteriad.</p> <p> Female sexual characters: Leg-pairs 1 considerably, 2 slightly, ticker than following legs. Vulva (Fig. 10E) stout, slightly compressed on sides; median cleft positioned sub-apically, surrounded by a narrow oval median field (<i>mf</i>); operculum (<i>op</i>) slightly higher than bursa, apically concave, ending up with a blunt hyaline protrusion on each side; two smaller and tapering protrusions present apically on bursa; each bursal valve bearing three vertically arranged setae, operculum non-setose. RS composed of a very thin and not too long central tube (<i>ct</i>) leading to a distinct, nearly spherical, central ampulla (<i>ca</i>), and a somewhat thicker and more strongly curved posterior tube (<i>pt</i>) ending in an ovoid posterior ampulla (<i>pa</i>).</p> <p> <b>Distribution</b> (Fig. 14, red circle). <b>Romania:</b> South Carpathians: Căpătânii Mts: Mt Stogu (type locality).</p>Published as part of <i>Vagalinski, Boyan, Evsyukov, Aleksandr P., Chumachenko, Yuri A. & Zabiyaka, Igor Y., 2023, A review of the genus Micropachyiulus Verhoeff, 1899 and description of the related Armeniopachyiulus gen. nov. (Diplopoda: Julida: Julidae: Pachyiulini), pp. 221-246 in Zootaxa 5239 (2)</i> on pages 235-239, DOI: 10.11646/zootaxa.5239.2.3, <a href="http://zenodo.org/record/7624205">http://zenodo.org/record/7624205</a&gt

Armeniopachyiulus pokr Vagalinski & Evsyukov & Chumachenko & Zabiyaka 2023, gen. et sp. nov.

<i>Armeniopachyiulus pokr</i> gen. <i>et</i> sp. nov. <p>Figs 11–13</p> <p> <b>Material examined</b> (ZMUM). <b>Holotype:</b> ♂ (in two pieces with dissected gonopods), Lesser Caucasus, Armenia, W of Shamshadyn, halfway between Ijevan & Berd, 1500–1600 m, <i>Fagus</i>, <i>Carpinus</i>, <i>Acer</i> etc. forest, in litter and under bark, 26–27.V.1987, S. Golovatch & K. Eskov leg.;</p> <p> <b>Paratypes:</b> 1 ♂ (in two pieces with dissected gonopods), 1 ♀ (unbroken), same collecting data as for holotype; 1 ♂ (gnathochilarium, antennae, gonopods, flanges of pleurotergum 7, leg pairs 1 & 2, leg 3, and most of trunk prepared for SEM), SW of Shnogh, halfway between Alaverdi & Bagratashen, <i>Carpinus</i> forest, litter, 24. V.1987, S. Golovatch & K. Eskov leg.; 1 ♂ (in 2 pieces, with dissected gonopods, left opisthomere damaged, left promere accidentally lost), 1 ♀ (in 2 pieces, leg pair 2 with vulvae dissected), Armenia, Yeghegnut, ca 20 km N of Kirovakan [Vanadzor], 1200–1250 m a.s.l., <i>Quercus</i>, <i>Carpinus</i>, <i>Acer</i> etc. forest, 23. V.1987, S. Golovatch & K. Eskov leg.</p> <p> <b>Etymology.</b> From the Armenian word for ‘small’, ‘petty’, ‘minute’, after the size of this new species.</p> <p> <b>Description.</b> Measurements: Holotype with BRF 36 + 3 + T, L = 8.2 mm, H = 0.6 mm; paratype ♂♂ with BRF 35–40 + 1–3 + T, L = 8.4–8.5 mm, H = 0.45–0.55 mm; paratype ♀♀ with BRF 40–43 + 1–3 + T, L = 9–10 mm, H = 0.51–0.56 mm.</p> <p>Colouration (after more than 30 years of ethanol conservation) (Fig. 11): mostly pallid, with traces of darker transverse stripes above ozopore level and brownish tinges at paraprocts.</p> <p>Head (in Fig. 11A): With 3–5 pigmented ommatidia on each side. Vertigial, supralabral and labral setae: 2, 4 and 14, respectively.Antennae (Fig. 12A) 1.45 times as long as head in males and 1.3 times in females; antennomere 2 = 5> 3 = 4> 6; 5 ca 1.5 times as long as broad and ca 1.7 times as broad as 2; 5 and 6 with a row of several sensilla basiconica dorsolaterally at distal margins, those on 5 of similar size as the four apical sensilla, those on 6 considerably smaller. Mandibular stipites in males not expanded. Labrum tridentate. Gnathochilarium (Fig. 12B) with 4 instead of 3 distal setae on each stipes (the latter being the normal state in Julidae), basal part of stipites non-setose, stipital palps relatively small; promentum rather small, dividing lamellae linguales by ca 2/5 of their length, the latter each bearing three setae in a row.</p> <p>Trunk and legs: Collum mostly smooth, with only several short and fine striae near posterolateral corner. Body rings considerably vaulted. Prozonae almost completely smooth, with only a few sparse and very shallow longitudinal striae. Metazonae shallowly and discontinuously striated; metazonal margins with a whorl of 20–25 erect setae, these being 0.2 (females) or 0.25 (males) times as long as H. Ozopores set closely behind pro-metazonal suture— either touching it or at a distance of less than 1x their diameter. Walking legs relatively short: ML ca 0.7 times as long as H in males and ca 0.6 times in females. Tarsus of ML ca 1.5 as long as tibia and ca 2.5 times as long as apical claw. Legs 1 (in females), 2 and 3 (Fig. 12D, E) with an accessory claw, following legs without.</p> <p>Telson (in Fig. 11B): Pre-anal ring rather densely covered with long setae. Epiproct slightly bent ventrad, proximally roof-like, distally forming a slender, sharply pointed, hyaline tip reaching level of tip of paraproctal setae. Hypoproct broadly rounded, not protruding beyond hind contour of paraprocts in both sexes, ventrally with two median submarginal setae. Paraprocts moderately densely setose, without distinct row of shorter setae along posterior margins.</p> <p> Male sexual characters: Legs 1 (Fig. 12C) 3-segmented, compact hooks oriented mesad; tibial outgrowth rather long and slender, tarsal remnant indistinct; the distal podomere baso-mesally with a verrucose hump (<i>h</i>). Legs 2 (Fig. 12D) significantly ticker and slightly longer than following legs; adhesive pads absent from all legs. Flanges of pleurotergum 7 (Fig. 12F) gradually narrowing, ending with a small, rounded lobe, directed fronto-ventrad. Penis very small, weakly chitinized, hidden deeply in its sac above coxae 2, with short and broad, well-divided apical lobes.</p> <p> Gonopods (Fig. 13A–E) <i>in situ</i> mostly concealed in gonopodal sinus, only tips of promeres visible on the outside. Promere (Fig. 13A) slender, somewhat higher than opisthomere, sigmoid in both anterior-posterior and lateral-mesal views, gradually narrowing towards a rounded apex directed somewhat mesad; posterior surface with a well-developed mesal ridge (<i>mr</i>) reaching to ca promere mid-height, a very small lateral ridge (<i>lr</i>), and a long, arched distal ridge (dr) bearing 2–3 dense rows of denticles; a broad and deep median groove (<i>mg</i>) between mesal and lateral ridges. Opisthomere (Fig. 13B–E) rather stout; mesomeral process (<i>m</i>) mostly fused to the solenomere, with a bulging basal part being reciprocal to the median groove of the promere, distally free, directed partly anteriad, apically finely and irregularly branched; posterior lamella (<i>l</i>) well-developed, thick, expanding mesad, mostly concealing solenomere from mesal view, meso-apically forming a groove surrounded by short fringes; solenomere (<i>s</i>) simple, meso-laterally flattened, bent frontad, apically forming a fovea (<i>fo</i>).</p> <p> Female sexual characters: Legs 1 significantly, legs 2 slightly ticker than leg-pair 3 and following pairs. Vulva (Figs 13F) cylindrical, mostly symmetrical; the two bursal valves separated only apically by a small, oval median cleft (<i>mc</i>), this being surrounded by a broad median field (<i>mf</i>); operculum (<i>op</i>) slightly higher than bursa, both bursa and operculum ending with large ear-like hyaline protrusions; only 2 pairs of setae distally on bursa, operculum nonsetose. RS composed of a long and mostly straight central tube (<i>ct</i>), slightly enlarged at bottom, and a long, narrow and folded posterior tube (<i>pt</i>) leading to a small piriform posterior ampulla (<i>pa</i>).</p> <p> <b>Distribution</b> (Fig. 14, yellow squares). <b>Armenia:</b> Armenian Lesser Caucasus (type locality).</p>Published as part of <i>Vagalinski, Boyan, Evsyukov, Aleksandr P., Chumachenko, Yuri A. & Zabiyaka, Igor Y., 2023, A review of the genus Micropachyiulus Verhoeff, 1899 and description of the related Armeniopachyiulus gen. nov. (Diplopoda: Julida: Julidae: Pachyiulini), pp. 221-246 in Zootaxa 5239 (2)</i> on pages 240-243, DOI: 10.11646/zootaxa.5239.2.3, <a href="http://zenodo.org/record/7624205">http://zenodo.org/record/7624205</a&gt

Micropachyiulus Verhoeff 1899

Genus <i>Micropachyiulus</i> Verhoeff, 1899 <p> <i>Micropachyiulus</i> Verhoeff, 1899: 184 (described as a subgenus of <i>Pachyiulus</i> Berlese, 1886).</p> <p> <i>Hylopachyiulus</i> Attems, 1904: 183 (described as a subgenus of <i>Pachyiulus</i> Berlese, 1886), <b>syn. nov.</b></p> <p> <b>Type species:</b> <i>Pachyiulus (Micropachyiulus) paucioculatus</i> Verhoeff, 1899, by monotypy.</p>Published as part of <i>Vagalinski, Boyan, Evsyukov, Aleksandr P., Chumachenko, Yuri A. & Zabiyaka, Igor Y., 2023, A review of the genus Micropachyiulus Verhoeff, 1899 and description of the related Armeniopachyiulus gen. nov. (Diplopoda: Julida: Julidae: Pachyiulini), pp. 221-246 in Zootaxa 5239 (2)</i> on page 224, DOI: 10.11646/zootaxa.5239.2.3, <a href="http://zenodo.org/record/7624205">http://zenodo.org/record/7624205</a&gt

Micropachyiulus ocellatus Vagalinski & Evsyukov & Chumachenko & Zabiyaka 2023, comb. nov.

<i>Micropachyiulus ocellatus</i> (Antić & Akkari, 2018), comb. nov. <p> <i>Hylopachyiulus ocellatus</i> Antić & Akkari, 2018 (in Antić <i>et al.</i> 2018): 231–234, figs 4, 5, 8C, D.</p> <p> <b>Diagnosis.</b> A species of <i>Micropachyiulus</i> (always?) with ommatidia. Very similar to <i>Micropachyiulus corylorum</i>, <i>Micropachyiulus pygmaeus</i>, and <i>Micropachyiulus paucioculatus</i> in terms of gonopod conformation, and especially in the shape of the solenomere which ends up with a minute, transversely oriented apical projection. Clearly distinguishable from all these species by the very short and blunt (vs. long and pointed) epiproct. Differs further from <i>M. corylorum</i> by the absence of a rod-like process next to the solenomere; from <i>M. pygmaeus</i> by the solenomere considerably overreaching the mesomeral process, rather than the two being subequal in height; and from <i>M</i>. <i>paucioculatus</i> by a thicker, apically fimbriate rather than smooth posterior lamella of the opisthomere, a much shorter (barely vs. considerably overreaching apical part of posterior lamella) solenomere and a stouter apical outgrowth of the mesomeral process, oriented considerably more anteriad rather than being mostly parallel to the main axis of the opisthomere.</p> <p> <b>Distribution</b> (Fig. 14, pink circles). <b>Croatia:</b> Dicmo (type locality). <b>Austria:</b> Vienna, Grinzing (D. Antić and J. Gruber, pers. comm.).</p> <p> <b>Remarks.</b> According to fig. 5A in Antić <i>et al.</i> (2018), males of <i>M. ocellatus</i> <b>comb. nov.</b> have humps basomesally on the distal podomere of legs 1, like those observed in other species of the genus (see below).</p> <p> According to unpublished observations of Jürgen Gruber (formerly in NHMW) based on numerous individuals from Grinzing, most adults have 1–4 ommatidia on each side of the head, while some seem to lack ommatidia altogether. However, the latter condition might be a false impression caused by the absence of pigmentation from the ommatidia, which is quite common in this species. Additional careful observations are needed to either confirm or reject the existence of an anophtalmous form of <i>M. ocellatus</i> <b>comb. nov.</b>.</p> <p> Considering the high level of endemism within <i>Micropachyiulus</i> and the more than 500 km in a straight line between the type locality of <i>M. ocellatus</i> <b>comb. nov.</b> and Vienna, the latter record is almost certainly a case of human introduction.</p>Published as part of <i>Vagalinski, Boyan, Evsyukov, Aleksandr P., Chumachenko, Yuri A. & Zabiyaka, Igor Y., 2023, A review of the genus Micropachyiulus Verhoeff, 1899 and description of the related Armeniopachyiulus gen. nov. (Diplopoda: Julida: Julidae: Pachyiulini), pp. 221-246 in Zootaxa 5239 (2)</i> on page 227, DOI: 10.11646/zootaxa.5239.2.3, <a href="http://zenodo.org/record/7624205">http://zenodo.org/record/7624205</a&gt