Mesotritia nuda ( Berlese, 1887 )

Liu, Dong & Chen, Jun, 2010, A review of Mesotritia (Acari: Oribatida: Oribotritiidae) in China, with descriptions of two new species and a checklist of known taxa, Zootaxa 2479, pp. 39-58 : 51-54

Mesotritia nuda ( Berlese, 1887)

( Figs. 31–50 )

Tritia nuda Berlese, 1887 , p. 9; 1896, p. 20, figs. 1–6; Sellnick, p. 40, figs 6, 17, 29.

Oribotritia nuda: Hammen, 1959 , p. 35.

Mesotritia (Entomotritia) nuda: Märkel, 1964 , p.43.

Mesotritia nuda: Aoki, 1980 , p. 72; Balogh & Mahunka, 1983, p. 168; Niedbała, 1993, p. 44, figs. 17–41; Mahunka, 1994, p. 240, fig. 2; Niedbała, 2001, p. 296, figs. 44–50; 2002, p. 33, figs. 120–141; 2003, p. 274, figs. 70–73; 2004a, p.33, fig. 16 (K–N); 2006, p. 12, fig. 5(A–D); 2008a, p. 117; 2008b, p. 763.

Oribotritia brachythrix Walker, 1965 , p. 52, figs. 23–26; Niedbała, 2001, p. 296, figs. 44–50.

Mesotritia brachythrix: Grandjean, 1967 , p. 252; Märkel, 1968, p. 732; Aoki, 1980, p.72; Marshall, Reeves & Norton, 1987, p. 66.

Mesotritia elastica Sergienko, 1988 , p. 66, figs. 1–10; Niedbała, 1993, p. 44, figs. 120–141.

Mesotritia (Entomotritia) piffli Märkel, 1964 , p. 39, fig. 9; Gilyarov, 1975, p. 380.

Mesotritia piffli: Aoki, 1980 , p. 72; Balogh & Mahunka, 1983, p. 169; Niedbała, 1993, p. 44, figs. 120–141.

Material examined: Five adults (in alcohol, W-90-19), China: Sichuan Province, Nanping County, Jiuzhaigou (33°15'40.80"N, 104°14'7.81"E), Wucai Lake, from litter, 2800M, 5 Jul., 1990, leg. Fu-Sheng Huang; one adult (in alcohol, W-90-20), China: Sichuan Province, Nanping County, Jiuzhaigou (33°15'40.80"N, 104°14'7.81"E), Changhai, from litter, 3100M, 5 Jul., 1990, leg. Fu-Sheng Huang; one adult (in alcohol, LD-013), China: Gansu Province, Kangle County, Lianhua Mountain (34°56'25.17"N, 103°45'58.94"E), from litter, 2900M, 2 Sep., 1990; one adult (in alcohol, W-97-17), China: Beijing, Mentougou District, Xiaolongmen National Nature Reserve (39°57'57.32"N, 115°26'28.95"E), from litter, 6– 7 Oct., 1997, leg. Hui-Fu Wang and Jun Chen; one adult (in alcohol, CJ-02-38), China: Beijing, Huairou District, Labagoumen (40°57'8.91"N, 116°29'11.57"E), Wulongtan, from litter under robur, 20 Jun., 2002, leg. Jun Chen; one adult (in alcohol, CJ-05-5), China: Beijing, Miyun District, Shicheng (40°33'46.82"N, 116°47'54.98"E), Jiudaowan, from litter under shrub, 13 May, 2005, leg. Jun Chen; one adult (in alcohol, WuX-7), China: Hebei Province, Yu County, Huliuhe Reservoir (39°48'14.13"N, 114°29'7.09"E), from moss under tree of Populus , 5 Jun., 1985, leg. Hui-Fu Wang. Newly recorded from China.

Measurements: Specimens (n=5) from Sichuan and Gansu Provinces: Prodorsum: length 425–490, width 305–335, height 125–180; notogaster: length 770–960, width 515–601, height 590–710. One specimen from Sichuan Province: prodorsal setae: ss 75, ro 145, in 70, le 145, ex 65, distance between setae: ro -ro 55, in -in 215, le -le 225; notogastral setae: c1 100, c2 80, c3 75, c p 65, d1 100, d2 80, e1 80, e2 70, h1 75, h2 75, h3 60, ps1 80, ps2 70, ps3 60; distance between setae: c1-d1 190, d1-e1 210, e1-h1 205, h1-ps1 205; ventral region: genitoaggenital plate 217.5×100, ano-adanal plate 390×55. Specimens (n=5) from Beijing and Hebei Province: Prodorsum: length 285–335, width 205–225, height 100–115; notogaster: length 561–640, width 365–375, height 415–435. One specimen from Beijing: prodorsal setae: ss 75–80, ro 95, in 45, le 95, distance between setae: ro -ro 25, in -in 155, le -le 160; notogastral setae: c1 60, c2 40, c3 40, c p 45, d1 45, d2 45, e1 45, e2 55, h1 30, h2 45, h3 35, ps1 45, ps2 40, ps3 35; distance between setae: c1-d1 135, d1-e1 180, e1-h1 185, h1-ps1 140; ventral region: genito-aggenital plate 155×75, ano-adanal plate 282.5×50.

Prodorsum with one simple, long and strong lateral carina on each side; sensilli smooth and fusiform (specimens from Sichuan and Gansu Provinces) (figs. 34, 50) or with narrow stalk and fusiform head (specimens from Beijing and Hebei Province) (figs. 40, 47–49); lamellar, interlamellar and rostral setae long, smooth and attenuate; rostral setae near each other and located slightly (most specimens examined) ( Figs.47– 49 ) or more (only one specimen from Beijing, W-97-17) (fig. 40) anterior to interlamellar setae; mutual distance between interlamellar setae slightly shorter than that between lamellar setae; exobothridial setae short and fine; comparative length: ro = le> ss> in> ex. Notogaster with fine, short and attenuate setae; setae of row c remote from anterior border, setae c1 more than setae c2 and c3. Six to seven (one specimen from Gansu Province, LD-013) pairs of genital setae, short (specimens from Beijing and Hebei Province) (fig. 39), or slightly longer (specimens from Gansu and Sichuan Provinces) (fig. 31), and two pairs of aggenital setae present; anal plates with two pairs of short anal setae (specimens from Gansu and Sichuan Provinces slightly longer), setae an1 situated between setae ad2 and ad3; three pairs of adanal setae present, setae ad2 situated more close to ad3 than to ad1, setae ad3 short, setae ad1 and ad2 long; lyrifissures iad situated laterally or posterior to setae an2. Setae h of mentum considerably longer than distance between them; setation of legs (without tarsi): I: 1-3-4(2)-5(1); II: 1-4-4(1)-4(1), III: 2-3 or 2-2(1)-2(1), IV: 2-3-2-2(1); all legs heterotridactylous.

Distribution. China (Beijing, Gansu, Hebei, Sichuan), Austria, Canada, Chile, Ecuador, Germany, Italy, Central America (Antilles, Bermuda, Costa Rica, Cuba, El Salvador, Jamaica, Saint Andrews, Saint Eustatius), Mexico, Poland, South Africa, Sweden, Ukraine, U.S. A..

Remarks. After examining all Chinese specimens, some characters show individual variation, such as the shape of sensilli, the length of genital and anal setae and the number of genital setae. These are all subject to intraspecific variability.

Figures

FIGURES 31 – 38. Mesotritia nuda (Berlese, 1887) (specimen from Sichuan): 31, lateral view of body (legs removed); 32, prodorsum, dorsal view; 33, ventral plate; 34, sensillus, dorsal view; 35 – 36, trochanter, femur, genu and tibia: 35, leg I; 36, leg II; 37 – 38, femur, genu and tibia: 37, leg III; 38, leg IV. Scale bars: 31 – 33, 35 – 38 = 100 μm; 34 = 50 μm.

FIGURES 39 – 46. Mesotritia nuda (Berlese, 1887) (specimen from Beijing): 39, lateral view of body (legs removed); 40, prodorsum, dorsal view; 41, ventral plate; 42, mentum of infracapitulum; 43 – 44, trochanter, femur, genu and tibia: 43, leg I; 44, leg II; 45 – 46, femur, genu and tibia: 45, leg III; 46, leg IV. Scale bars = 100 μm.

FIGURES 47 – 50. Mesotritia nuda (Berlese, 1887): 47 – 48, prodorsum, dorsal view (specimen from Beijing); 49, prodorsum, dorsal view (specimen from Hebei); 50, sensillus (specimen from Gansu). Scale bars: 47 – 49 = 100 μm; 50 = 50 μm.