Pterygosoma orbicularis Jack, 1962

Fajfer, Monika, 2020, A systematic revision of the scale mite genus Pterygosoma Peters, 1849 (Acariformes: Pterygosomatidae), Zootaxa 4805 (1), pp. 1-147 : 119-120

Pterygosoma orbicularis Jack, 1962 ( Figs 110 and 111 ) new status

Pterygosoma spinosa orbicularis Jack, 1962: 588 , fig. 8

Type host: Agama agama (Sauria: Agamidae ) Type locality: Somalia (Goolis Mts).

Redescription. FEMALE (based on lectotype and 1 paralectotype from Agama agama ). Gnathosoma . Chelicerae 270 long; slender distal part 175–180 long, swollen cheliceral part 90–95 long. Fixed cheliceral digit with minute tines, about 10 long. Setae dF and dG subequal in length, 60–65 long. Palpal tibia with small claw. Palpal tarsi with 3 setae. Subcapitulum with filiform setae n, about 20 long. Peritremes about 160 long. Hypostome with smooth apex, 190–210 long. Idiosoma 630–645 long and 935–945 wide. Dorsum. Antero-lateral part with about 90 pairs of serrate setae, 20–65 long; postero-lateral part with 3 pairs of slightly apically expanded setae, 95–185 long; medial part with 2 pairs of dorso-median setae dm1 and dm2. Setae dm1 serrate, 45 long, setae dm2 apically expanded with minute spicules on apical part, 60–65 long. Posterior part with 27–32 pairs of smooth tapered or apically expanded peripheral setae, 245–375 long. All peripheral setae inserted terminally, except for 2 pairs of setae inserted dorsally (1 pair near genital region and 1 pair near lateral margin of idiosoma ). Eyes absent. Venter. Setae vm1 filiform, vm2 and vm3 with barely discernible serration. Genital slit situated mainly dorsally. Genital series represented by 3 pairs of spine-like setae g1–g3. Setae g1 and g2 15–20 long, setae g3 40–45 long. Pseudanal series represented by 5 pairs of paddle-shaped setae ps1–ps5 with minute spicules on apical part, 125–140 long. Legs chaetotaxy as in inermis group i.e. setae of trochanters I–IV (1–1–1–1), femora I–IV (3–1–1–1), genua I–IV (2–0–0–1), tibiae I–IV (5–3–3–3). All setae on each podomere filiform, except for slightly serrate setae dFI–IV. Setation of tarsi I−IV as in group A: I 13 setae (ft, tc’, tc”, p’, p”, a’, a”, it’, it”, u’, u”, vs’, vs”) and solenidion ω1; II 8 setae (tc’, p’, p”, a’, a”, u’, u”, vs’) and ω1; III and IV with 8 setae each (tc’, p’, p”, a’, a”, u’, u”, vs’). Setae tc’ of legs II–IV and a’, a”, u’, u”, vs’, vs ” of legs I–IV smooth.

MALE. Unknown.

Type material (examined). Female lectotype and 1 female paralectotype ( NHM no. 1966.2.22.345–346) from Agama agama (Linnaeus) (Sauria: Agamidae ) ( NHM no. 1905.11.7.8–9), SOMALIA: Berbera: Goolis Mts, 7 November 1905, coll. G. W. Bury.

Type material deposition. All types deposited in the NHM .

Host and distribution. This species is known only from Agama agama from Somalia [Berbera, Goolis Mts] ( Jack 1962a).

Remarks. This species was originally described as a subspecies of Pterygosoma spinosa ( Jack 1962b) . Howev- er, the morphological differences between P. spinosa and P. spinosa orbicularis allow me to elevate this subspecies to species level. P. orbicularis differs from P. spinosa by the presence of the rounded idiosoma , subequal setae dF and dG, smooth hypostomal apex, the absence of setae d’GI and presence of tapered or slightly apically expanded peripheral setae. In P. spinosa the idiosoma is much wider than long, setae dG are longer than dF, the hypostome has teeth at the apex, setae d’GI are present and the peripheral setae situated laterally are fine-pointed.

Moreover, this species redescription shows that the majority of the peripheral setae are inserted terminally (vs. most of setae are inserted dorsally according to the original description), setae dF and dG are subequal in length (vs. setae dG are longer than dF), setae dGI are absent (vs. setae dGI are present) and the peripheral setae are tapered or slightly apically expanded (vs. fine-pointed).

Figures

FIGURE 110. Pterygosoma orbicularis Jack, 1962, female in dorsal view.

FIGURE 111. Pterygosoma orbicularis Jack, 1962, female. A, ventral view; B, tarsus I in dorsal view; C, tarsi I in ventral view.