Mesotritia serrata, Liu, Dong & Chen, Jun, 2010

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 : 46-49

Mesotritia serrata sp. nov.

( Figs. 14–23 )

Material examined: Holotype: Adult (in alcohol, Yao-27), China: Hunan Province, Yuelushan Mt. (28°11'15.87"N, 112°55'25.76"E), from litter, 25 Aug., 1983, leg. Wen-Bing Yao. Paratype: three adults (in alcohol, Yao-27), with same data as holotype.

Etymology. The specific name “ serrata ” is from Latin, and refers to the serrate lateral margin of the prodorsum.

Diagnosis: Lateral margin of prodorsum serrate; one pair of lateral carinae present; sensilli short, smooth and spindle-shaped, other prodorsal setae long, smooth and attenuate, except exobothridial setae fine and short; rostral setae situated nearly at the level of interlamellar setae; in -in <le -le; genito-aggenital plates with six pairs of genital and two pairs of aggenital setae of unequal length; one pair of anal and three pairs of adanal setae present, ad2-ad3 <ad2-ad1; lyrifissures iad situated anterior to anal setae.

Measurements: Holotype: Prodorsum: length 305, width 210, height 85, setae: ss 55, ro 105, in 85, le 105, ex 30, distance between setae: ro -ro 45, in -in 130, le -le 145; notogaster: length 580, width 350, height 385; setae: c1 85, c2 70, c3 60, c p 70, d1 75, d2 60, e1 50, e2 60, h1 55, h2 55, h3 55, ps1 60, ps2 50, ps3 45; distance between setae: c1-d1 135, d1-e1 175, e1-h1 190, h1-ps1 150; ventral region: ad1 90, ad2 50, ad3 16, genitoaggenital plate 145×70, ano-adanal plate 290×60. Paratypes: Prodorsum: length 265–300, width 185–210, height 90–98; notogaster: length 465–552, width 302–350, height 340–405.

Colour yellowish to grey-yellowish. Surface of body finely dotted. Lateral margin of prodorsum serrate.

Prodorsum with one simple, long and strong lateral carina on each side; sensilli short, smooth and spindleshaped; lamellar, interlamellar and rostral setae long, smooth and attenuate; rostral setae situated nearly on level of interlamellar setae; mutual distance between interlamellar setae shorter than that between lamellar setae; exobothridial setae short and fine; comparative length: ro = le> in> ss> ex.

Notogaster with fine, short (c1 / c1-d1 =0.63), attenuate setae; setae of row c remote from anterior border, c1 further, c3 closer.

Genital plates with six pairs of minute setae; two pairs of aggenital setae present, setae ag2 longer than ag1; anal plates with one pair of minute anal setae; three pairs of adanal setae present, setae ad2 situated more close to ad3 than to ad1, setae ad1 longest, ad3 shortest; lyrifissures iad situated anterior to anal setae.

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: 2-3-2(1)-2(1), IV: 2-3-2-2(1); all legs heterotridactylous.

Distribution. Only known from type locality.

Remarks. This new species is similar to M. okuyamai Aoki, 1980 , but differs by following characters: in M. serrata , lateral margin of prodorsum serrate; rostral setae situated nearly on level of interlamellar setae. In M. okuyama , lateral margin of prodorsum smooth; rostral setae situated nearly on level of lamellar setae. In addition, these two species also differ from each other by the slightly different shape of sensilli and different setation of legs.

Figures

FIGURES 14 – 21. Mesotritia serrata sp. nov.: 14, lateral view of body (legs removed); 15, prodorsum, dorsal view; 16, ventral plate; 17, mentum of infracapitulum; 18 – 21, trochanter, femur, genu and tibia: 18, leg I; 19, leg II; 20, leg III; 21, leg IV. Scale bars: 14 – 16, 18 – 21 = 100 μm; 17 = 50 μm.

FIGURES 22 – 23. Mesotritia serrata sp. nov.: 22, lateral view of body; 23, serrate margin of prodorsum (indicated by the black arrow).