Priscapalpus De Leon, 1961

Farzan, Sadegh, Asadi, Mahdieh, Ueckermann, Edward A., Seeman, Owen D. & Beard, Jennifer J., 2013, A review of Amblypalpus and Priscapalpus (Acari: Trombidiformes: Tenuipalpidae), including two new species of Amblypalpus from Iran, Zootaxa 3716 (1), pp. 53-64 : 54-55

Priscapalpus De Leon, 1961

Type species: Priscapalpus macropilis De Leon, 1961: 94 . By monotypy

Diagnosis. Palps 2-segmented; palp tarsus with 2 phaneres and 1 dorsal seta; anterior margin of prodorsum with long, narrow forked projection extending medially, with small lateral projection; opisthosoma with 8–9 pairs of setae (c2, d2, e2, f2 absent; e1 present or absent); some dorsal setae much longer and thicker than other dorsal setae, except f3, h2, and h1 short, narrow, setiform; dorsal cuticle and leg cuticle heavily sculptured with tubercles; ventral and genital shields fused in large broad shield, weakly developed, transversely striate; genital setae arranged more or less transversely along posterior margin of shield; metapodal shields absent; 2 pairs of ps setae, anal plate well defined, setae ps1 on small tubercle with seta curving upwards around body margin, ps1 – 2 inserted transversely on anal plates; trochanter IV bare; genu III–IV with 1 seta; tibia I–II with 5 setae; tarsi 9(1)-9(1)-5-5 (seta tc′′ present); empodia claw-like. Spermatheca unknown.

Remarks. Priscapalpus De Leon is a small genus previously comprising three species from the Neotropical and Afrotropical regions (De Leon 1961, 1965; Meyer 1979; Mesa at al. 2009). Our concept of the genus is reduced to exclude the Afrotropical species Priscapalpus thomissus Meyer , which is now placed in Amblypalpus . Thus, Priscapalpus now comprises just P. macropilis and P. cherretti , both from the Neotropical region.

After examining the type specimens of Priscapalpus macropilis , P. cherretti , and P. thomissus , it was revealed that several generic-level characters in the original descriptions were inaccurate, and that the former two species share several characters that the latter species does not. Priscapalpus thomissus does not have fused ventral and genital plates, there are no setae in the F-row, the anterior margin of the prodorsum has a lobed projection (two large median lobes flanked by two smaller lateral lobes), trochanter IV has one seta (nude in macropilis and cherretti ), genua III–IV are nude (one seta present in macropilis and cherretti ), and tarsal claws are pad-like.

The two current members of the genus are highly distinctive flat mites, but resemble the diverse and widespread genus Brevipalpus by lacking dorsal setae c2, d2 and e2 (one species also lacks e1). Unlike Brevipalpus , Priscapalpus has fewer palpal segments (2 versus 4), anal setae set transversely on the anal plates (medially and longitudinally in Brevipalpus ), and ventral and genital plates fused into a single broad shield (always strongly developed in Brevipalpus ), and tarsal claws are uncinate. Furthermore, some dorsal setae are several times longer than others, whereas most Brevipalpus have all dorsal setae more or less of subequal length, or have differences that are not quite as striking.

A further two Oriental species, Priscapalpus gurdaspurensis Kaur and Sadana, 1999 and Priscapalpus piarai Sadana and Sidhu, 1989 , are incertae sedis because they were described from immature stages (Mesa et al., 2009). These species are certainly not Priscapalpus because they have four-segmented palps and the dorsal setae are all subequal in length. The immature stage of Priscapalpus is known for the deutonymph of P. macropilis only, which —like the adult—has some extremely long dorsal setae, although some of these setae change form between the deutonymph and adult (De Leon 1961). Both incertae sedis species match the deutonymphs of Brevipalpus and here considered to represent this genus.