Paratydeidae Baker, 1949

Khaustov, Alexander A., 2017, Review of the Paratydeidae (Acari: Prostigmata), with description of three new species, Zootaxa 4303 (2), pp. 151-212 : 153

Family Paratydeidae Baker, 1949

Diagnosis. FEMALE. Gnathosoma . Chelicerae finely striated, separated, with one pair of simple cheliceral setae (cha) situated in distal part. Movable digit of chelicera sickle-like. Palps four-segmented. Palp setation: tr 0, FeGe 2 (dFe, dGe), Ti 3 (d, l’, l”), Ta 7(1) (ba, bp, va, vp, ul’, ul”, sul, ω); ul” and sul always eupathidion-like; ul’ often eupathidion-like. Solenidion ω fused with tarsus forming sensory pit in Tanytydeus or erect in other genera. Subcapitulum with four pairs of simple setae (m, n, or 1, or 2). Pharynx thin-walled, smooth, subrectangular.

Peritremes and trachea. Peritremes linear, with several chambers, widened at distal ends. Trachea very long and thin, arising from stigmata near base of chelicerae, reaching to posterior end of body. Main tracheal trunk usually subdivided into several additional trunks.

Idiosoma. Body long and narrow, soft and finely striated. Type of striation uniform for all studied species ( Figs. 5 A, B, 13A, B, 29A, B). Prosoma and hysterosoma clearly separated by sejugal furrow; hysterosoma subdivided into 3 to 7 parts by transverse folds (number of transverse hysterosomal rows is variable and depends on slide mounting and probably physiological condition of mounted specimen). Prodorsum subtriangular, with three pairs of setae (ve, sci, sce); setae sci situated in bothridia. Median part of prodorsum usually with weakly defined longitudinal crista-like prodorsal shield. Two pairs of eyes situated laterally to setae ve in Scolotydaeus , posterior pair of eyes usually much smaller than anterior and in some specimens difficult to discern; or eyes absent in Neotydeus and Tanytydeus . Two pairs of short, blunt-ended supracoxal setae (ep, el) situated anterolaterad to prodorsum. Hysterosoma with four pairs of cupules; im, ip situated dorsally; ia and ih situated ventrally. Hysterosoma dorsally with nine setae (c 1, c 2, d, e, f 1, f 2, h 1, h 2, ps 1) and with five pairs of ventral setae around anal opening (ps 2, ps 3, ad1, ad 2, ad 3; seta ad 1 in dorsal or ventral position). Anal covers anteromedially to setae ad 3 with oval pits. Genital and anal openings separate but situated close to each other. Number of genital and aggenital setae is greatly variable. Genital opening with two or three genital acetabulae and three pairs of setae k. Eugenital setae absent. Coxal fields I and II joined together, but separated medially. Coxal fields I with four pairs of setae (1 a, 1 b, 1 c, 1 d); coxal fields II with three pairs of setae (2 a, 2 b, 2 c). Coxal fields III and IV joined together, but separated medially. Coxal fields III with two pairs of setae (3 b, 3 c); coxal fields IV with two pairs of setae (4 a, 4 b). Setae 3 a situated in the space between coxal fields II and III.

Legs. Legs 5-segmented; femora I and IV divided into basi- and telofemur by ventral suture. Tarsi of all legs with one pair of simple claws and claw-like empodium. Leg I distinctly longer and thicker than leg II. Solenidia on genu, tibia and tarsus of legs I and II and on tibia of leg III erect or fused with leg segment (in Tanytydeus ). Tarsus II with spine-like famulus (Fuangarworn pers. com.). Leg setation variable in different species. Leg setal development from larva to adults is described below for Scolotydaeus uralensis sp. nov. and Tanytydeus cubanus sp. nov.

MALE. In general similar to female except genital region. Part of genital setae usually modified (branched, claw-like); genital opening with eugenital setae situated on genitalia.

LARVA. With three pairs of legs. Genital opening and genital acetabulae absent. Setae ad 1-3 absent. Coxal fields I with two pairs of setae (1 a, 1 b) and mushroom-like Claparede organ; coxal fields II with one pair of setae (2 a); coxal fields III with one pair of setae (3 b). Trochanters II and III without setae.

PROTONYMPH. Setae 2 c absent. Coxal fields IV without setae. Genital opening short, with one pair of genital acetabulae and one pair of setae k. One pair of aggenital setae.

DEUTONYMPH. Coxal fields IV with one pair of setae (4 a). Genital opening with two pairs of genital acetabulae and two pairs of setae k. Two pairs of genital and aggenital setae.

TRITONYMPH. Similar to adults. Genital and anal openings widely separated. Female tritonymph with simple genital setae; male tritonymph usually with branched genital setae.

Figures

FIGURE 5. Scolotydaeus tauricus (Kuznetsov, 1973) comb. nov., male: A—body in dorsal view, B—body in ventral view.