Philippipalpus Corpuz-Raros, 1978

Beard, Jennifer J., Seeman, Owen D. & Bauchan, Gary R., 2014, Tenuipalpidae (Acari: Trombidiformes) from Casuarinaceae (Fagales), Zootaxa 3778 (1), pp. 1-157 : 111-112

Philippipalpus Corpuz-Raros, 1978

Type species. Philippipalpus agohoi Corpuz-Raros, 1978 , by original designation.

Diagnosis. All life stages: dorsal opisthosoma with 10 pairs of lanceolate to weakly palmate setae; c2, d2 and f2 absent; setae e 2 in marginal position, aligned with c3, d3, e3, and f3; setae h2 similar in size and form to other dorsal setae; palps 5-segmented, palp setal formula 0, 0, 0, 2, 3(1); immature stages with anterior margin of prodorsum smoothly rounded, without projections/notches; ventral plate absent; 3 pairs of pseudanal setae (ps1–3) on weakly developed membranous anal plates. Adult female: gnathosoma usually completely concealed by prodorsum; anterior margin of prodorsum with deep medial notch, forming 1 pair of broad fleshy lobes each bearing setae v2 (usually inserted beneath a fold); genital plate weakly developed, membranous; metapodal plates not developed; coxae I without 1c; trochanters I–IV 0-0-1-0 (v ′ absent on tr I–IV; l ′ present on tr III); femora I–IV 3-3 -2-1; genua 1-1-0-0 (d present on ge I–II); tibiae 4-4-2-2 (seta d absent ti III–IV); tarsi I–IV without tc′′. Solenidia of male similar in thickness and length to those of female.

Remarks. Smiley et al. (1996) and Mesa et al. (2009) described the genus with setae d2 present and e2 absent; however we feel that d2 is in fact absent and e2 is present on the margin, as in most of the related tegopalpine genera ( Beard et al. 2013).

Species of Philippipalpus are morphologically similar to species in the genera Tegopalpus and Chaudhripalpus , as all three genera have dorsal setae c2 absent and three pairs of ps setae present (ps1–3). Philippipalpus can be separated from both these genera by the presence of dorsal setae e2 (absent in both Tegopalpus and Chaudhripalpus ). Species of Philippipalpus are separated here using subtle differences in ornamentation, striation and measurements, unlike the other genera of Tegopalpinae. We feel that because each new species of Philippipalpus presented here occupies a single host species, and no other species of flat mite in this subfamily inhabits more than one species of she-oak, it is evidence to support their separation at the species level. Nevertheless, we acknowledge further collecting from a greater geographical range is warranted to test the validity of these species.

Philippipalpus is unusual in lacking both setae v ′ on all trochanters (l ′ present on tr III) and d on tibiae III–IV.