Oribotritia hunchunensis, Liu, Dong, 2015

Liu, Dong, 2015, Review of Oribotritia (Acari, Oribatida, Oribotritiidae) with a world checklist and description of a new species from China, Zootaxa 4007 (2), pp. 217-241 : 219-221

Oribotritia hunchunensis sp. nov.

( Figs 1 A–H)

Diagnosis. Entire surface punctate; two pairs of lateral carinae present, upper ones composed with about three lines, lower ones thinner and shorter; sensilli rough and setiform; interlamellar and rostral setae stout, erect and rough; lamellar and exobothridial setae smooth and fine; comparative lengths: in> ss> ro>ex> le, in–in / ro–ro≈ 1.7; notogastral setae similar in shape to rostral setae, setae c 3 are the smallest; h> h–h; setation of palps: 0-3-0-3-9(1); epimeral setal formula: 3-0-2-2; genital setae with formula: 7:2; setae ag 2 longer than ag 1; three pairs of anal and three pairs of adanal setae present; lyrifissures iad placed between level of setae ad 3 and an 3; femora I with distinct distal spines; setae d on femora I near distal end.

Description. Measurements. Holotype: prodorsum: length 700, width 550, height 202, setae: ss 210, ro 175, in 285, le 98, ex 102; notogaster: length 1390, width 1020, height 890; c 1 225, c 3 150, c p 210, d 1 205, d 2 210, e 1 200, e 2 200, h 1 245, h 2 210, h 3 165, ps 2 150, ps 3 125, ps 3 125; ag 1 55, ag 2 75; genito-aggenital plate 350×150, ano-adanal plate 750×120. One of paratypes: prodorsum: length 740, width 570, height 208; notogaster: length 1650, width 1160, height 1030; genito-aggenital plate 368×160, ano-adanal plate 765×125.

Integument. Very large species. Colour brown. Entire surface punctate, anterior part of prodorsum with distinct striations.

Prodorsum ( Figs 1 A–B). Two pairs of lateral carinae present, upper ones composed of about three lines, lower ones thinner and shorter, about half length of upper ones; sensilli (ss) rough and setiform; interlamellar and rostral setae (in and ro) stout, erect and rough; lamellar and exobothridial setae (le and ro) smooth and fine; comparative lengths: in> ss> ro> ex> le, in–in / ro–ro≈ 1.7.

Notogaster ( Fig. 1 A). Notogastral setae fairly short (c 1/ c 1– d 1 ≈ 0.5), similar in shape to rostral setae, setae c 3 are the smallest; setae c 2 further away from anterior border than setae c 1 and c 3.

Ventral region ( Figs 1 A, C–G). Setae h of mentum considerably longer than distance between them; setation of palps: 0-3-0-3-9(1); epimeral setal formula: 3-0-2-2. Nine pairs of genital setae (g) arranged with formula: 7:2; two pairs of aggenital setae located longitudinally, setae ag 2 longer than ag 1; three pairs of anal and three pairs of adanal setae present, all minute; setae ad 3 situated between level of setae an 2 and an 3; lyrifissures iad placed between level of setae ad 3 and an 3.

Legs ( Figs 1 H). Setal counts for leg segments: 1-4-5(2)-5(1)-22(3); II: 1-4-4(1)-5(1)-21(2), III: 3-2-3(1)-4(1)- 15, IV: 3-2-2(1)-3(1)-14; femora I with distinct distal spines; setae d on femora I near distal end.

Material examined. Holotype: 1 adult ( NIGA, in alcohol), China: Jilin Province, Yabian, Hunchun, from litter under tree, 3 Apr. 2015, leg. Dong Liu. Paratypes: 2 adults ( NIGA, in alcohol), same data as holotype.

Etymology. The new specific name “ hunchunensis ” refers to the type locality, Hunchun in Jilin Province, China.

Remarks. This species is very large. It distinguishable from congeners by presence of two pairs of prodorsal lateral carinae (upper ones composed with about three lines, lower ones short), stout and rough interlamellar, rostral and notogastral setae, fine and smooth lamellar, three pairs of anal and three pairs of adanal setae, lyrifissures iad placed anterior to setae ad 3, and femora I with distinct distal spines.

Compared with O. asiatica Hammer, 1977 , these two species are similar in having rigid, erect interlamellar, rostral and notogastral setae, similar shape of sensilli, three pairs of anal and adanal setae, but this new species can be differed by the following features: 1) two pairs of lateral carinae on prodorsum (versus one pair in O. asiatica ); 2) setae c 2 further away from anterior border than setae c 1 and c 3 (versus setae c 1 and c 2 more so); 3) interlamellar, rostral and notogastral setae rough (versus sparsely barbed); 4) aggenital setae longer (versus minute); 5) lyrifissures iad placed anterior to setae ad 3 (versus at the level of setae ad 2 or between setae ad 2 and ad 3); 6) femora I with distinct distal spines (versus without).

It is also similar to O. gigas Bayoumi & Mahunka, 1979 in having rigid, erect interlamellar, rostral and notogastral setae, similar shape of sensilli, but this new species can be distinguished by 1) two pairs of lateral carinae on prodorsum (versus one pair in O. gigas ); 2) interlamellar, rostral and notogastral setae rough (versus sparsely barbed); 3) nine pairs of genital setae (versus eight pairs); 4) aggenital setae longer (versus minute); 5) three pairs of anal setae (versus one or two pairs); 6) femora I with distinct distal spines (versus without).

Figures

FIGURE 1. Oribotritia hunchunensis sp. nov.: A, lateral view of body (legs removed); B, prodorsum, dorsal view; C, right side of genito-aggenital plate; D, right side of ano-genital region; E, infracapitulum, palpi removed; F, palp, antiaxial view; G, chelicera, antiaxial view; H, femur I. Scale bars: A = 200 Μm; B – D = 100 Μm; E – H = 50 Μm.