Anadenosternum Athias-Henriot

Fenďa, Peter, 2017, A revision of the genus Anadenosternum Athias-Henriot (Acari: Mesostigmata: Parasitidae), Zootaxa 4324 (3), pp. 436-450 : 437-438

Genus Anadenosternum Athias-Henriot

Anadenosternum Athias-Henriot, 1980: 286 .

Type species: Parasitus azaleensis Daele, 1975 , by original designation.

Diagnosis. Adults are distinguished from other genera of Parasitidae by the following characters: podonotum with 23 pairs of setae; opisthonotum hypertrichous, with 28–34 pairs of setae; all dorsal setae smooth, fine, needle-like, and mostly subequal in thickness and length. Palpfemoral seta al serrate; palpgenual seta al1 rodlike, and seta al2 divided into four or five tines. Epistome with three prongs, middle prong longer than lateral prongs; anterolateral margins delicately denticulate. Distal anterolateral margins of coxae II and III serrated. Tarsi II and III with setae al2, pl2, av2, pv2 and mv strongly pilose, setae al1 and pl1 only slightly pilose and seta pv1 thickened and smooth; tarsus IV with seta pd2 very long and setae pv2, pl3 pilose, also seta av1 slightly pilose. Seta al on trochanter I with one lateral tine on each side; trochanter IV with a small acuminate dorsal tubercle. Epigynial shield of females triangular, with pointed anterior apex, strongly concave anterolateral margins and posterior margin straight or slightly convex; figura cuneata in the form of flat-iron; endogynial sac rounded or oval. Peritrematal shields of females with anterior ends narrowly connected to podonotal shield. Legs II of males just slightly thickened, with weak apophyses.

Description. ADULTS. Dorsal idiosoma. Dorsal shield divided into podonotal and opisthonotal shields, with a pattern of reticulation on surface; the pattern wih transverse lines dominant, more prominent on opisthonotum. Podonotum with 23 pairs of setae; opisthonotum hypertrichous, with 28–34 pairs of setae; setae often with asymmetrical positions. In female, dorso- and ventrolateral soft integument with 9–10 pairs of setae, including one pair of r-setae close to posterolateral angles of podonotal shield; these setae inserted on expanded and fused dorsal and ventral shields in male. Dorsal setae smooth, fine, needle-like, and mostly subequal in thickness and length.

Ventral idiosoma. Tritosternum of females with narrow base and two long laciniae, tritosternum of males with markedly shortened base. In females, presternal area normally with three pairs of small platelets: two medially situated pairs suboval, transversely oriented and obviously differing in length (smaller one rarely absent); anterolateral pair subtriangular, expressed also in male. Posterior margin of sternal shield of females shaped into obtuse angle. Epigynial shield triangular, with pointed anterior apex, strongly concave anterolateral margins and posterior margin straight or slightly convex; figura cuneata in the form of flat-iron; genital lyrifissures (iv5) placed on the shield or occasionally on soft integument between epigynium and opisthogaster. Endogynial sac rounded or oval. Ventrianal shield well reticulated, with 10–11 pairs of ventral setae plus three circum-anal setae; lines of reticulation undulate in circum-anal area (also on posteriormost surface of opisthonotal shield). Peritrematal shields with anterior ends narrowly connected to podonotal shield in female; posterior ends connected to ventrianal shield in female or holoventral shield in male; peritremes thin, reaching level of setae j2 anteriorly. Exopodal shields II-III small, subtriangular, free from peritrematal shields. Gland pores gv1 and gv3 absent, gland pores gv2 with two openings.

Gnathosoma . Palpfemoral seta al serrate; palpgenual seta al1 rodlike, and seta al2 divided into four or five tines. Epistome trifid, with middle prong longer than lateral prongs; anterolateral margins delicately denticulate. Corniculi simple, horn-like. Hypostome with ten rows of denticles. Movable digit of females normally with three teeth, occasionally with one or two minute accessory denticles; arthrodial corona in female simple, produced into a setiform brush in male. Fixed digit of males with a row of minute denticles; dorsal seta with fine serration.

Legs. Setation of legs I–IV: coxae 2, 2, 2, 1; trochanters 6, 5, 5, 5; femora 13 (2-5/4-2), 11 (2-5/3-1), 6 (1-4/1- 0), 6 (1-4/1-0); genua 13 (2-6/3-2), 11 (2-5/2-2), 9 (2-4/2-1), 10 (2-5/2-1); tibiae 14 (2-6/4-2), 10 (2-4/ 2-2), 8 (2-3/ 2-1), 10 (2-4/2-2); tarsi II–IV 18 (3-7/5-3). Legs II of male just slightly thickened, with weak apophyses. Distal anterolateral margins of coxae II and III serrated. Seta al on trochanter I with one lateral tine on each side; trochanter IV with a small acuminate dorsal tubercle; femur IV with seta pd1 thickened; tarsi II and III with setae al2, pl2, av2, pv2 and mv strongly pilose, setae al1 and pl1 only slightly pilose and seta pv1 thickened and smooth; tarsus IV with seta pd2 very long and setae pv2, pl3 pilose, also seta av1 slightly pilose.