Damaeus (Paradamaeus) yushuensis, Xie, Lixia, Yan, Yi, Huang, Rong & Yang, Maofa, 2011

Xie, Lixia, Yan, Yi, Huang, Rong & Yang, Maofa, 2011, First record of the subgenus Damaeus (Paradamaeus) Bulanova-Zachvatkina (Oribatida, Damaeidae) from China, with description of a new species, ZooKeys 160, pp. 47-57 : 48-52

Damaeus (Paradamaeus) yushuensis sp. n. Figs 1-6

Material examined.

Holotype: male (in alcohol, QHYS-XLX-8-5), China, Three Rivers' Headwaters Natural Reserve Area of Yushu Tibetan Autonomous Prefecture, Qinghai province (32°33'48.65"N, 97°39'55.66"E), from soil under the Picea crassifolia , 3464M, 5 Aug., 2009, col. Lixia Xie. Paratypes: Three females (in alcohol, QHYS-XLX-8-5), same data as holotype; Two males (in alcohol, QHYS-XLX-8-6), same data as QHYS-XLX-8-5, from soil under the Kobresia pygmaea .

Diagnosis.

Propodolateral apophysis P distinct, with broader base and arched tip; setae ro slightly barbed, setae le heavily barbed, thick. Sensillus short, thick, heavily barbed and rod-like. Interlamellar setae long, rather thick and conspicuously barbed. Prodorsal tubercles Da, Dp absent, Ba well developed, Bp weakly developed. Spinae adnatae beak like, short, distinct, strongly curved inwards (about 30 µm in total), with broader base and quite sharp tip. Notogastral setae smooth, slender except c- series and p- series. Setae of c- series rather thick, with conspicuously barbed and frizzled tip, oriented forwards and the rest backwards.

Comparative length of notogastral setae: lp<lm= ps3<ps2<la= h3= h2= h1<ps1<c1<c2. Epimeral setae mostly smooth except 1b, 1c, 3b, 3c, 4d and hypostomal setae a, m, h. Seta 1a, 2a and 3a rather short. Epimeral setal formula: 3-1-3-4. Enantiophyses E2 and V present, E2p and Vp weakly developed, E2a and Va well developed. Parastigmatic tubercle Sa long, acuminate, with sharp tip; Sp small, triangular. Hypostomal setae a, h and m thin, slightly barbed. Legs rod-like and longer than body.

Description of adult.

Dimensions. Holotype: Body length 980; length of prodorsum: 420, width 280, height 370, setae: ss 175, in 100, le 150, ro 125, ex 75, distance between setae: ro-ro 110, in-in 125, le-le 125, in-le 105, le-ro 40; length of notogaster: 700, width 670, height 780; setae: c1 135, c2 175, la 110, lm 95, lp 90, h3 110, h2 110, h1 110, ps1 125, ps2 105, ps3 95; c1-c2 75, c2-c2 275, la-la 375, lm-lm 435; ventral region: genito-aggenital plate 225 × 220, ano-adanal plate 190 × 175. Paratypes: length of prodorsum: 415-425, width 275-285, height 365-375; length of notogaster: 695-705, width 665-670, height 775-780; ventral region: genito-aggenital plate 220 × 215, ano-adanal plate 185 × 170.

Integument. Surface of body and leg segments with filamentous cerotegument. Conspicuous microtubercles present on prodorsum and around leg acetabula, legs with dense fungal mycelic.

Prodorsum (Fig. 1). Triangular, propodolateral apophysis P distinct, with broader base and arched tip. Lamellar setae (le) and rostral setae (ro) both in dorsalaterad position, long, arched and tapered. Lamellar setae with obvious barbs, thick, being longer than slender, weakly barbed rostral pair. Bothridia well developed, funnel-like, with broad margin and pair of thick, heavily barbed sensillus. Interlamellar setae (in) long, thick and conspicuously barbed (specially in holotype). Exobothridial setae (ex) thick, with obvious barbs, frizzled. Comparative length of prodorsal setae: ex<in<ro<le<ss. Weakly developed transverseridge connected to the base of bothridium and directed to median end of prodorsum. Prodorsal tubercles Da absent, Ba distinct; Bp weakly developed, usually as tuberculate sclerotised ridge, in light microscope sometimes discernible only in lateral view.

Notogaster (Fig. 1). Circular viewed perpendicular to circumgastric scissure, length almost equivalent to wider. Spinae adnatae beak like, short, distinct, strongly curved inwards (about 30 µm in length), with broader base and quite sharp tip. Notogastral setae short, smooth, slender except c- series and p- series. Setae of c- series rather thick and long, with conspicuous barbed and frizzled tip, oriented forwards and the rest backwards. Comparative length of notogastral setae: lp<lm= ps3<ps2<la= h3= h2= h1<ps1<c1<c2. Pseudanal setae comparatively long, with obvious barbs, attenuate.

Ventral region. (Fig. 2). Epimere I with medial pit (cp). Epimeral setae mostly smooth except 1b, 1c, 3b, 3c, 4d; setae 1c, 3b, 3c, 4d long, with obvious barbs; Seta 1a, 2a and 3a rather short, lanciform. Epimeral setal formula: 3 –1–3– 4. Ano-genital setal formula: 6 –1–2– 3. Enantiophyses E2 and V present, E2a triangular with pointed tip; E2p weakly developed, usually as tuberculate sclerotised ridge. Ventrosejugal tubercle Va large, strong, represented by broad ridge; Vp represented by low, broadly curved ridge, with setae 3b Parastigmatic tubercle Sa long, acuminate, with broader base and heavily pointed tip; Sp small, triangular; Discidium (di) long, acuminate, with broader base and heavily pointed tip, directed posterolaterad.

Gnathosoma. Infracapitular mentum without noticeable microtubercles. Hypostomal setae a, m, h slender, weakly barbed. Chelicera rather strong, fixed and movable digits with four blunt teeth; setae cha with obvious barbsand chb smooth. Palpal setation: 0 –2–1–3– 8, including solenidion ω (Fig. 4M).

Legs. (Figs 5-6). Monodactylous, moderately long, leg I, III, IV longer than body, leg II shorter than body. Relative length of femur to tarsus of legs I to IV 1: 0.88: 1.01: 1.2. Leg IV 1.3 times ventral body length. Femur IV 1.4 times length of trochanter IV, proximal stalk 1.4 times length of bulb. Leg setae medium in length and thick, mostly with distinct short barbs on outer curvature. Setal formulas of legs as follows (from trochanter to tarsus, famulus and solenidia included): I: 1 –7– 4 (1)-4 (2)-20 (2); II: 1-6-4 (1)-4 (1)-18 (2); III: 2-4-3 (1)-3 (1)-16 (0); IV: 1-4-3 (1)-3 (1)-15 (0). Solenidia of genua I-II with compan ion seta d. Solenidia δ equivalent to seta d on genuaI, Solenidia δ shorter and thinner than seta d on genuaII. Solenidion φ 1 on tibia I 3 times longer than φ 2. Seta d absent from all tibiae, solenidia on all tibiae free, as usual for genus.

Etymology.

The specific name is derived from the type locality, Yushu Tibetan Autonomous Prefecture, Qinghai province.

Remarks.

This new species is characterised by following characters: interlamellar setae (in) long, rather thick and conspicuously barbed; spinae adnatae beak like, short, distinct, strongly curved inwards; c-series rather thick, long with conspicuous barbed and frizzled tip, oriented forwards and the rest backwards, other notogastral setae smooth, slender and short, except p- series (see Table 1).