Periseius Womersley

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 : 20

Periseius Womersley (5 described species)

Movable and fixed cheliceral digits with 3–7 and 5–11 teeth, respectively. Epistome with an anteromedian extension wider at base, acute distally, serrated. Seta h 3 about in longitudinal line with h 1 and slightly posterior and mediad to h 2. Idiosoma elongated or suboval, 350–560 µm long and 150–350 µm wide at widest level. Podonotal and opisthonotal shields separated. Dorsal idiosomal setae aciculate or spatulate and smooth or pilose. Podonotal region of dorsum with 21–23 pairs of setae, of which 21–23 pairs on podonotal shield and without setae on soft integument along lateral margins of podonotal shield. Opisthonotal region with 19–21 pairs of setae, of which 19– 21 pairs on opisthonotal shield and without setae on soft integument along lateral margins of opisthonotal shield. Seta j 1 not on prominent protuberance, as long as or shorter than r 3 and shorter than Z 5. Opisthonotal and ventrianal shields separated. With three pairs of presternal platelets. Sternal shield fused only by a narrow strip to endopodal shield near coxa IV; st 4 slightly lateral to st 1– st 3 (st 4 on soft integument in P. nobskae ). Opisthogaster without platelets between genital and ventrianal shields; with seven pairs of setae on ventrianal shield and without setae on soft integument around ventrianal shield; post-anal seta longer 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 and to ventrianal shield, with connection behind stigma wider than peritreme (not fused in P. hammeni ). Exopodal shields near coxae II–III–III divided at median level of coxa III. Without distinct metapodal platelets. All legs with pretarsi. Genua I, III and IV and tibia IV with 13, 9, 10 and 10 setae, respectively.