Evanssellus Ryke

Castilho, Raphael C., Silva, Edmilson S., De, Gilberto J. & Halliday, Bruce, 2016, Catalogue of the family Ologamasidae Ryke (Acari: Mesostigmata), Zootaxa 4197 (1), pp. 1-147: 12

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http://doi.org/ 10.5281/zenodo.168445

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Evanssellus Ryke


Evanssellus Ryke  (2 described species)

Movable and fixed cheliceral digits with 2–3 and 2–4 teeth, respectively. Epistome with an anteromedian extension wider at base. Seta h 3 about in longitudinal line with h 1 and slightly posterior and mediad to h 2. Idiosoma elongate, 470–550 µm long and 300–320 µm wide at widest level. Podonotal and opisthonotal shields separated. Dorsal idiosomal setae aciculate, pilose or leaf-like. Podonotal region of dorsum with 21–22 pairs of setae, of which 21 pairs on podonotal shield and 0–1 pair on soft integument along lateral margins of podonotal shield. Opisthonotal region with 20 pairs of setae, of which 20 pairs on opisthonotal shield and without setae on soft integument along lateral margins of opisthonotal shield. Seta j 1 on prominent protuberance, longer or shorter than r 3 and Z 5. Opisthonotal and ventrianal shields separated. With 1 pair of presternal platelets. Sternal shield not fused to endopodal shield near coxa IV; setae st 1– st 4 in longitudinal line (st 4 absent in E. medusa  ). Opisthogaster without platelets between genital and ventrianal shields; with 4–7 pairs of setae on ventrianal shield and 0–2 pairs on soft integument around ventrianal shield; post-anal seta as long as or shorter than para-anal seta. Peritreme with straight or smoothly curved margins, extending anteriorly to level of coxa I. Peritrematal shield fused posteriorly to exopodal shield near coxa IV, with connection behind stigma wider than peritreme. Exopodal shields near coxae II –III –III fused. Without distinct metapodal platelets. Leg I without pretarsus; legs II-IV with pretarsi. Genua I, III and IV and tibia IV with 13, 9, 10 and 10 setae, respectively. Setae av2, pv2 on tibia I long, thick, spine-like.