Katydiseiinae, Fain & Lukoschus, 1983

Lindquist, Evert E., Oconnor, Barry M., Shaw, Matthew D. & Sidorchuk, Ekaterina A., 2020, Review of the genera Berlesia Canestrini, 1884, and Katydiseius Fain & Lukoschus 1983, the subfamily Katydiseiinae Fain & Lukoschus, 1983, and their family group relationships (Acari: Mesostigmata: Gamasina), with description of three new species parasitic on gryllacridid crickets (Orthoptera), Zootaxa 4857 (1), pp. 5-70 : 44

Key to genera and species of Katydiseiinae , adult females

1. Dorsal vertex setae j1 absent (not to be confused with j3, present slightly behind level of poroids id-1); sternal shield reduced, bearing only setae st1, without endopodal extensions between bases of legs I–II and II–III; anal shield with paranal setae inserted at mid-level of anus; subcapitulum with hypostome prolonged anteriorly by two paramedian processes reaching level of palptibia and enveloping extremities of internal malae and labrum; coxa of legs I–IV with all setae setiform; genua of legs I-II-III with 8-6-6 setae, each lacking al-2, pl-2......................................................................................................... Genus Katydiseius , monobasic, K. nadchatrami Fain & Lukoschus, 1983

- Dorsal vertex setae j1 present (inserted slightly anteromediad poroids id-1, closely anterior to j3); sternal shield well developed, bearing setae st1, st2, with endopodal extensions between bases of legs I–II and II–III; anal shield with paranal setae inserted at level of, or behind, posterior margin of anus; subcapitulum with sclerotized extensions of hypostome extended only as corniculi to level of palptrochanter, but with flexible mouthpart structures (salivary styli, internal malae, labrum) extending freely to level of palpgenu; coxa of legs I–III and sometimes IV each with one seta strongly bulbiform basally; genua of legs I-II-III with minimally 11-10-9 setae, each with al-2, pl-2 ... Genus Berlesia Canestrini, 1884 ............................... 2

2. Coxal seta of leg IV conspicuously bulbiform, similar to one of coxal setae on each of legs I–III and subcapitular setae pc; anal shield lateral margins nearly parallel; tarsi II–IV each with one of apical setae distinctively longer than adjacent setae and as long as entire pretarsus.............................................................. B. rapax Canestrini, 1884

- Coxal seta of leg IV setiform, in contrast to a bulbiform coxal seta on each of legs I–III and subcapitulum; anal shield subrhomboidal, lateral margins angular; tarsi II–IV each with apical setae similar in length, none as long as entire pretarsus........ 3

3. Vertex setae j1 moderately long, z1 present; dorsal shield with mid–dorsal setae (j4–j6, z5, J1–J3) also moderately long (J2 present), e.g., j4 nearly as long as interval j4–j5; dorsal shield flanked by about 25 pairs of setae, mostly of the hypertrichous r–R and S series; soft opisthogastric cuticle also hypertrichous, with about 15 pairs of setae........... B. multisetosa n. sp.

- Vertex setae j1 short, z1 absent; dorsal shield with mid-dorsal setae also short (J2 absent), e.g., j4 ca one-fourth as long as interval j4–j5; dorsal shield flanked by at most 15 pairs of setae mostly of the r–R and S series; soft opisthogastric cuticle with at most 7 pairs of setae................................................................................... 4

4. Dorsal shield with setae j3 and z4 very long, longer than diagonal interval j3–z4 and twice as long as transverse interval j3–j3, and with setae J4 absent; metapodal plates ovoid, nearly as wide as long; dorsal palpfemoral seta d extending beyond apex of palpgenu; leg I genu and tibia each with 10 or 11 setae, third ventral (av-2) absent.................... B. vorontsovi n. sp.

- Dorsal shield with setae j3 and z4 moderately long, shorter than interval j3–z4 and no longer than interval j3–j3, and with minute setae J4 present; metapodal plates slender/baculiform, three times as long as wide; dorsal palpfemoral seta d extending to about mid-level of palpgenu; leg I genu and tibia each with 12 setae, third ventral (av-2) present....... B. hospitabilis n. sp.