Eustigmaeus extremiorientalis Khaustov 2016, n. sp.
Creators: name: Khaustov, A. A.
Publisher: name: Zenodo
Year: 2016
Subjects: Biodiversity
Taxonomy
Animalia
Arthropoda
Arachnida
Trombidiformes
Stigmaeidae
Eustigmaeus
Eustigmaeus extremiorientalis

description: <i>Eustigmaeus extremiorientalis</i> n. sp. <b>(Figures 1-6)</b> Description <i>Female</i> (Figures 1-6) — Idiosoma almost round in outline. Length of idiosoma 340 (320 – 340), width 270 (270 – 280). <i>Idiosomal dorsum</i> (Figures 1A, 5A, B, 6A, B) — Idiosoma completely covered by 2 large and well sclerotized plates. Plates with large round dimples (Figures 1A, 5A, 6B) and weak subcuticular reticulation. Dorsal setae situated on short protuberances, subequal, widened distally and strongly barbed (Figures 5A, B). Setae <i>e</i> 2 absent. Setae <i>h</i> 1 and <i>h</i> 2 situated ventrally. Setae <i>h</i> 2 only slightly thickened, not widened distally and weakly barbed. Lengths of dorsal setae: <i>vi</i> 42 (40 – 43), <i>ve</i> 50 (48 – 51), <i>sci</i> 38 (37 – 40), <i>sce</i> 31 (30 – 33), <i>c</i> 1 40 (39 – 41), <i>c</i> 2 28 (27 – 29), <i>d</i> 1 41 (40 – 43), <i>d</i> 2 35 (34 – 36), <i>e</i> 1 43 (42 – 44), <i>f</i> 1 46 (43 – 46), <i>h</i> 1 33 (31 – 34), <i>h</i> 2 19 (17 – 20). <i>Idiosomal venter</i> (Figures 1B, 5C, 6C, D) — With 2 pairs of callosities between idiosomal plate and humeral plate. Anterior callosity slightly larger than posterior one (Figure 5C). Suranal plate situated ventrally, with distinct large dimples. Endopodal plates separated medially distinctly reticulated. Humeral plate subtriangular, with distinct large dimples. Most of ventral setae weakly barbed; with 2 pairs of simple subequal aggenital, and 3 pairs of simple pseudanal setae; setae <i>ps</i> 2 clearly shorter than subequal <i>ps</i> 1 and <i>ps</i> 3. Lengths of ventral setae: 1 <i>a</i> 23 (21 – 24), 1 <i>b</i> 22 (20 – 23), 1 <i>c</i> 16 (15 – 19), 2 <i>b</i> 16 (15 – 18), 2 <i>c</i> 17 (14 – 17), 3 <i>a</i> 20 (18 – 22), 3 <i>b</i> 16 (13 – 17), 3 <i>c</i> 16 (13 – 17), 4 <i>a</i> 19 (17 – 20), 4 <i>b</i> 17 (16 – 18), 4 <i>c</i> 15 (13 – 16), <i>ag</i> 1 16 (15 – 17), <i>ag</i> 2 18 (16 – 19), <i>ps</i> 1 14 (14 – 16), <i>ps</i> 2 11 (10 – 11), <i>ps</i> 3 16 (15 – 17). <i>Gnathosoma</i> (Figures 2, 5B, D, 6E, F) — Tibial claw well-developed. Setae <i>l’</i> on palpal tibia very short, spine-like (Figure 2B). Setae <i>d</i> and <i>l’</i> of palpal femur widened distally and strongly barbed; other palpal setae of femur, genu and tibia (except <i>l’Ti</i>) pointed and barbed; seta <i>va</i> of palp-tarsus weakly barbed; other setae of palp-tarsus smooth. Number of setae on palpal segments: Tr 0, Fe 3 (<i>d</i>, <i>l’</i>, <i>v"</i>), Ge 2 (<i>d</i>, <i>l"</i>), Ti 3 (<i>d</i>, <i>l’</i>, <i>l"</i>), Ta 8(1) (fused eupathidia <i>ul’</i>, <i>ul"</i>, <i>sul</i>, eupathidion <i>acm</i>, <i>ba</i>, <i>bp</i>, <i>lp</i>, 1 solenidion <i>ω</i>). Palpal supracoxal setae (<i>ep</i>) needlelike. Rostrum of subcapitulum (Figure 2C) short and wide. Subcapitular setae <i>or</i> 1 smooth, distinctly thickened, curved and blunt-ended; other subcapitular setae simple, pointed. Basal part of subcapitulum with numerous small dimples and weak subcuticular reticulation (Figure 5D). Length of subcapitular setae: <i>m</i> 19 (18 – 22), <i>n</i> 18 (17 – 21), <i>or</i> 1 12 (11 – 12), <i>or</i> 2 12 (11 – 12). Chelicerae dorsally with numerous small dimples (Figure 5B). Legs (Figures 3, 4) — Empodial raylets capitate. Leg I (Figure 3A). Coxae I posterodorsally with needle-like leg supracoxal setae (<i>el</i>). Leg setation: Tr 1 (<i>v’</i>), Fe 6 (<i>d</i>, <i>l’</i>, <i>l"</i>, <i>v’</i>, <i>v"</i>, <i>bv"</i>), Ge 4 (<i>d</i>, <i>l’</i>, <i>l"</i>, <i>k</i>), Ti 5(2) (<i>d</i>, <i>l’</i>, <i>l"</i>, <i>v’</i>, <i>v"</i>, <i>Φ</i>, <i>Φp</i>), T <i>a</i> 13(1) (<i>p’</i>, <i>p"</i>, <i>tc’</i>, <i>tc"</i>, <i>ft’</i>, <i>ft"</i>, <i>u’</i>, <i>u"</i>, <i>a’</i>, <i>a"</i>, <i>pl’</i>, <i>pl"</i>, <i>vs</i>, <i>ω</i>). Setae (<i>p</i>) and (<i>tc</i>) of tarsus are eupathidia. Setae <i>d</i>, <i>l’</i>, <i>l"</i> of tibia, <i>l’</i>, <i>l"</i>, <i>d</i> of genu, <i>l"</i> and <i>d</i> of femur distinctly thickened distally and strongly barbed, situated on protuberances. Seta <i>k</i> 8 (8 – 9). Solenidion <i>ω</i> short 15 (13 – 15), finger-shaped; solenidia <i>Φ</i> 8 (8 – 9) and <i>Φp</i> 11 (10 – 11) baculiform. Setae (<i>ft</i>), (<i>pl</i>) and <i>vs</i> of tarsus weakly barbed; (<i>a</i>), (<i>u</i>) smooth. Leg II (Figure 3B). Leg setation: Tr 1 (<i>v’</i>), Fe 5 (<i>d</i>, <i>l’</i>, <i>l"</i>, <i>v’</i>, <i>bv"</i>), Ge 4 (<i>d</i>, <i>l’</i>, <i>l"</i>, <i>k</i>), Ti 5(1) (<i>d</i>, <i>l’</i>, <i>l"</i>, <i>v’</i>, <i>v"</i>, <i>Φ</i>), Ta 9(1) (<i>p’</i>, <i>tc’</i>, <i>tc"</i>, <i>u’</i>, <i>u"</i>, <i>a’</i>, <i>a"</i>, <i>pl’</i>, <i>vs</i>, <i>ω</i>). Setae <i>p’</i> and <i>tc’</i> of tarsus represented by eupathidia. Setae <i>d</i>, <i>l’</i> and <i>l"</i> of tibia, <i>d</i>, <i>l’</i> and <i>l"</i> of genu, <i>d</i> and <i>l"</i> of femur distinctly thickened distally and strongly barbed, situated on protuberances. Solenidion <i>ω</i> 9 (9 – 10) finger-shaped; solenidion <i>Φp</i> 7 (7 – 8) baculiform. Seta <i>k</i> 6 (5 – 6). Setae <i>tc"</i> and <i>vs</i> of tarsus weakly barbed; (<i>a</i>), (<i>u</i>) and <i>pl’</i> of tarsus smooth. Leg III (Figure 4A). Leg setation: Tr 1 (<i>v’</i>), Fe 3 (<i>d</i>, <i>l’</i>, <i>ev’</i>), Ge 1 (<i>d</i>), Ti 5(1) (<i>d</i>, <i>l’</i>, <i>l"</i>, <i>v’</i>, <i>v"</i>, <i>Φ</i>), Ta 7(1) (<i>tc’</i>, <i>tc"</i>, <i>u’</i>, <i>u"</i>, <i>a’</i>, <i>a"</i>, <i>vs</i>, <i>ω</i>). Solenidion <i>ω</i> 5 (4 – 5) baculiform; solenidion <i>Φp</i> 6 (5 – 6) baculiform. Setae <i>d</i>, <i>l’</i> of tibia, <i>d</i> of genu, <i>d</i> and <i>l’</i> of femur distinctly thickened distally and strongly barbed, situated on protuberances. Setae (<i>u</i>) of tarsus smooth, other tarsal setae weakly barbed. Leg IV (Figure 4B). Leg setation: Tr 1 (<i>v’</i>), Fe 2 (<i>d</i>, <i>ev’</i>), Ge 1 (<i>d</i>), Ti 5(1) (<i>d</i>, <i>l’</i>, <i>l"</i>, <i>v’</i>, <i>v"</i>, <i>Φ</i>), Ta 7(1) (<i>tc’</i>, <i>tc"</i>, <i>u’</i>, <i>u"</i>, <i>a’</i>, <i>a"</i>, <i>vs</i>, <i>ω</i>). Solenidion <i>ω</i> 4 (4 – 5) baculiform; solenidion <i>Φp</i> 6 (5 – 6) baculiform. Setae <i>d</i>, <i>l’</i>, <i>l"</i> of tibia, <i>d</i> of genu and femur distinctly thickened distally and strongly barbed, situated on protuberances. Setae (<i>u</i>) of tarsus smooth, other tarsal setae weakly barbed. Male and immatures: unknown. Type material — Female holotype, slide No ST181215, Russia: Primorskiy kray, Vladivostok, Botanical Garden-Institute, Far Eastern Branch of the Russian Academy of Sciences, 43°13’26.3"N, 131°59’34.6"E, from mosses on log, 18 December 2015, coll. S. Tupitsyn. Paratypes: 17 females, same data as holotype. Etymology — The new species name refers to its distribution in the Far East of Russia. Differential diagnosis — The new species is most similar to <i>E. absens</i> Do &amp;breve;gan, 2005, described from Turkey (Do &amp;breve;gan 2005), by the absence of setae <i>e</i> 2, presence of two callosities, only one seta on trochanter III and two pairs of aggenital setae. The new species differs from <i>E. absens</i> by distinctly thickened distally and strongly barbed dorsal idiosomal setae (vs. baculiform and weakly barbed in <i>E. absens</i>) and by setae <i>sci</i> longer than <i>sce</i> (vs. <i>sci</i> about two times shorter than <i>sce</i> in <i>E. absens</i>).
description: Published as part of <i>Khaustov, A. A., 2016, Two new species and a new record of mites of the family Stigmaeidae (Acari: Prostigmata) collected from mosses in Russia, pp. 321-339 in Acarologia 56 (3)</i> on pages 322-329, DOI: 10.1051/acarologia/20162249, http://zenodo.org/record/5398749