(Figures 7–11, 22, 26, 30, 34)
Material examined. Holotype: female collected in stand 940 -DD, plot 6 (56 ° 49 ' 5.753 '' N, 118 ° 21 ' 38.284 '' W) at EMEND research study site, northern area, from vascular plants and broadleaf-litter on forest floor, 8.09.2006, leg. Díaz-Aguilar, I. (deposited in CNC). Paratypes: stand 940 -DD, plot 6, northern area, from vascular plants and broadleaf-litter on forest floor, 8.09.2006., leg. Diaz-Aguilar, I. (3 females, 1 DN deposited in CNC, 1 female, 2 DN deposited in HNHM); stand 928 - MX, plot 1, northeastern area, from vascular plants and leaf-litter on forest floor, 9.09.2006, leg. Díaz-Aguilar, I. (2 females deposited in HNHM, 2 males deposited in CNC); stand 928 - MX, plots 1, 2 and 4, northeastern area, from vascular plants and leaflitter on forest floor, 9.09.2006, leg. Díaz-Aguilar, I. (30 females, 5 males, 2 DN); stand 930 -CD, plot 4, northeastern area, from mosses and needle leaf-litter on forest floor, 9.09.2006, leg. Díaz-Aguilar, I. (4 females); 940 -DD, plot 6, northern area, from vascular plants and broadleaf-litter on forest floor, 8.09.2006., leg. Diaz-Aguilar, I. (23 females, 8 DN).
Diagnosis. Adult female. Central and submarginal setae of podonotum smooth, except j 1, z 2 and s 6. J-, Z- and S-setae of opisthonotum pilose to varying degrees, R 1 slightly pilose, other marginal R-setae smooth, thorn-like. Central members of J and Z setal-row inserted on enlarged setal bases. Setae J 5 situated between dorsal cavities; Z 3 reaching bases of Z 4; S 1 situated close to Z 1, in posterolateral position. Pores Po 2 situated inside the line connecting Z 1 and Z 2. Podonotum covered by circular, squamous pattern, the area between J setal-rows ornamented with relatively large, subtriangular protuberances. Dorsal cavities weakly sclerotised, with undulate anterior margin. Posterior end of peritrematal shield rounded, reaching beyond level of R 3. Post-genital sclerites absent.
Description. Female. Length of idiosoma 342–360 μm (mean 355); width 244–252 μm (mean 250) (n = 7).
Dorsum (Figs 7, 22). Podonotum, 22 pairs of setae: j-row with six pairs, z-row with two pairs, s-row with six pairs, r-row with six pairs, p-row with two pairs. Setae j 1 plumose, z 2 and s 6 often barbed, s 3 elongate, plumose. Other j-, z- and s-setae short, smooth and needle-like. Marginal setae r 3 and r 6 elongate, plumose, other r setae shorter and delicately pilose (r 1 may be smooth). Peritrematal seta p 1 short and smooth, p 2 elongate and pilose; both visible in dorsal view. Pores po 1 situated on a line connecting the insertions of j 2 and s 1, po 2 lying on a line connecting j 4 and s 4, near s 4, po 3 inside the line connecting s 5 and s 6. Whole podonotum covered by small, circular, irregular squamous ornamentation, mostly arranged in curved lines in the center of the shield (Fig. 34). Circular ornamentation between setae z 1 well-developed, strongly sclerotised. Opisthonotum (Figs 26, 30) with 23 pairs of setae: J-row with six pairs, Z-row with five pairs, Srow with four pairs and R-row with eight pairs. Setae J 1 -J 5 elongate, pilose and pointed, J 1 situated close together, distance between their bases 16 μm, J 2 -J 5 diverging further away from each other. Setae J 5 situated between dorsal cavities, J 6 elongate, brush-like and plumose. Z 1 –Z 3 similar in shape and length to anterior Jsetae, Z 3 reaching bases of Z 4. Setae Z 4 long, broadening distally, brush-like and plumose, Z 5 short, delicately pilose. Setae S 1 similar in shape and length to Z 1, situated close to Z 1, distance between their insertions 11 μm. Setae S 2 -S 4 elongate, densely plumose, extending beyond lateral margin of opisthonotal shield. Setae S 2 situated anterolateral to Z 2. Eight marginal R-setae short, smooth and thorn-like; in some specimens R 1 delicately barbed. Setae J 1 -J 5, Z 1 -Z 4 and S 1 inserted on broad setal bases. Pores Po 2 -Po 4 enlarged, with undulate margins, Po 1 situated anterior to Z 1, Po 2 axial to a line connecting the insertions of Z 1 and Z 2, Po 3 enlarged, on a line connecting J 4 and Z 4, Po 4 on a line connecting Z 5 and S 4. Lateral parts of opisthonotum sparsely covered by large, bulging spots, central area around J setae with large, distinct, subtriangular protuberances forming a central star-like pattern. Dorsal cavities weakly sclerotised, uniform, with undulate anterior margin, axes parallel to that of the body. The length of opisthonotal setae and the distances between their insertions as in Table 2.
female male DN female male DN female male DN Venter (Fig. 8). Posterolateral ends of peritrematal shield arcuate, expanded posteriorly, reaching beyond level of R 3 setae. Peritremes straight, with bent anterior tips. Post-genital sclerites absent. Anterior margin of ventri-anal shield with two pairs of setae. Pre-anal setae short simple, post-anal seta elongate, distally pilose. Ventri-anal pores situated lateral to adanal setae. Sternal shield with reticulate ornamentation, ventri-anal shield covered by squamous pattern.
Male. Length of idiosoma 263–267 μm (mean 265); width 180 μm (n = 2). Chaetotaxy, poroidotaxy and sculpturing pattern of dorsal shields (Fig. 9) similar to female, but setae r 5 may be slightly pilose. On the ventral side (Fig. 10), sternogenital shield with straight posterior margin and five pairs of setae. Peritrematal shield and ventri-anal shield fused laterally, on the level of R 3 setae, not separated from the body margin. Post-genital sclerites absent. Ventri-anal shield with one pair of setae on the anterior margin and 17 ventri-anal setae (Fig. 10). The length of opisthonotal setae and the distances between their insertions as in Table 2.
Deutonymph (Fig. 11). Length of idiosoma: 275–283 μm (mean 280); width 178–188 μm (mean 185) (n = 3). Setae j 1 barbed, s 3, r 3 and r 6 long, brush-like, plumose, other podonotal setae smooth, simple. Chatetotaxy and poroidotaxy of opisthonotum as in adult stages. Podonotal circular, irregular-squamous pattern and circular sclerotised markings weakly developed, central and lateral parts of opisthonotum covered by circular protuberances. The length of J, Z and S setae and the distances between their insertions as in Table 2.
Protonymph and larva. Unknown.
Etymology. The species is dedicated to Mr. Jason Edwards, EMEND field coordinator.
Remarks. There is a difference in the number of setae on the anterior margin of the ventri-anal shield between male and female specimens. All females observed bear two pairs of setae on the anterior margin of ventri-anal shield, in contrast to male specimens, which generally had one pair of setae but sometimes two. Mixozercon jasoniana is closely related to M. albertaensis sp. nov., and M. borealis sp. nov. by the shape of the dorsal cavities and the presence of enlarged setal bases, and also resembles M. s tellifer on the basis of the similar sculpturing pattern and the pilosity of J-, Z-, and S-setae. The four species can be distinguished from each other according to the particular characteristics given in Table 4.