Ulyxes undefined-a

Ulyxes species A

Specimens examined. 1 female, 1 male, 2 deutonymphs (see Remarks), Spargo Creek, Wombat State Forest, Victoria, 29 Jan 1999, S. Ward coll., ex nestbox occupied by 19 adult and several juvenile Acrobates pygmaeus Feathertail Glider, nest 143.

Description of female. Dorsum. Large mite, 900 long. Dorsal shield almost textureless centrally, margins with fine reticulations, bearing 37 pairs of setae, z3 and px3 absent. Unpaired setae below J3 present. Discal setae minute. Z5 smooth, distinctly thickened, 5 wide.

Gnathosoma. Epistome a smooth lobe. Fimbriae on lateral arms of internal malae with distinctly expanded tips. Fixed digit with single tooth. Palp genu al1 not broadened or spatulate. Palp trochanter av seta distinctly broadened, sabre-shaped, 5 wide. Deutosternal groove with 6 rows of denticles, flanked by two lateral lines.

Venter. Sternal shield anterior edge subcuticular, posterior edge straight. Exopodal IV well-developed, 21 wide. Post-stigmatal shield abbreviated, with usual three pore-like structures. Genito-ventral shield extensive, reaching to within 4 of anal shield; without visible striae, possibly smooth. Zv1 thickened, distinctly peg-like. Opisthogaster bearing 29 pairs of setae excluding Jv1–3 and Zv1–2. Jv5 elongate, 93 µm (cf U. ulixes).

Legs. Chaetotaxy holotrichous for Laelapidae as defined by Evans (1963). Tarsus I lacks a forked sensory seta. Genu IV with single seta on pl face, distally placed thus pl2 appears absent or has migrated (cf. U. calypso, U. sisyphus, Figs 58, 59). Femur I ad1 long (50) and thick (6). Other d setae on femur II–III are slightly strengthened but none longer than 32 or thicker than 4. The following setae are apically bifid: femur I ad1, femur I pd2, femur II ad1, femur II ad2, femur III ad1, trochanterIV pl, femur IV ad1 and femur IV ad2. Trochanter I v seta thickened, peg-like. Trochanter IV ventral seta slightly thickened, not peg-like. Coxa II anterior seta thickened, peg-like; posterior seta slightly thickened, not peg-like. Coxa III anterior and posterior seta slightly thickened, not peg-like.

Description of male. Dorsal shield with long marginal setae (cf. U. ulixes). Fixed digit slightly reduced, no teeth in fixed digit. Genital opening subcircular, 20 wide, 18 deep. Zv1 setiform, not peg-like.

Remarks. The examined specimens cannot be figured or formally named because they were destroyed during an attempt to remount them. These notes are offered in case they help interpret future material. This is the first record of a Ulyxes species from a possum in the family Acrobatidae. In the same locality from which these specimens were found, five other nestboxes used by Acrobates did not contain Ulyxes sp. Nor did six other nestboxes used by Acrobates in SE Queensland.