Pterygosoma circularis Jack, 1962

Fajfer, Monika, 2020, A systematic revision of the scale mite genus Pterygosoma Peters, 1849 (Acariformes: Pterygosomatidae), Zootaxa 4805 (1), pp. 1-147 : 76-78

Pterygosoma circularis Jack, 1962 ( Figs 64 and 65 ) new status

Pterygosoma annectans circularis Jack, 1962: 581 fig. 2

Pterygosoma livingstonei Bertrand and Modry, 2004: 62 figs 1−6 syn. n.

Type host: Agama lionotus lionotus (Sauria: Agmidae). Type locality: Kenya (near Lake Baringo) .

Redescription. FEMALE (based on 1 lectotype and paralectotype from Agama lionotus lionotus ). Gnathosoma . Chelicerae 280–285 long; basal swollen part 95–100 long, slender distal part 185–190 long. Fixed cheliceral digit 15–20 long, with minute tines. Setae dF and dG, about 70 and 85 long, respectively. Palpal tibia with small claw. Palpal tarsi with 3 setae. Subcapitulum with filiform setae n, about 15 long. Peritremes about 150 long. Hypostome with smooth rounded apex, 200–215 long. Idiosoma 900–910 long and 855–980 wide. Dorsum. Antero-lateral part with about 85 pairs of slightly serrate setae, 55–60 long; medial part with 2 pairs of dorso-median setae dm1 and dm2. Setae dm1 slightly serrate, 55–60 long; setae dm2 slightly apically expanded, about 75 long. Peripheral series represented by 10–12 pairs of fine-pointed setae, 190–355 long: 6–7 pairs of these setae situated laterally, 4–5 pairs situated medially. Eyes absent. Venter. Setae vm1 filiform, vm2 and vm3 with barely discernible serration in apical half. Genital slit situated dorsally. Genital series represented by 4 pairs of spine-like setae g1–g4. Setae g1 conspicuous, about 30 long, setae g2–g4 minute, about 30 long. Pseudanal series represented by 4 pairs of apically expanded setae ps1–ps4, 40–80 long. Legs chaetotaxy as in mutabilis group i.e. setae of trochanters I–IV (1–1–1–1), femora I–IV (3–1–1–1), genua I–IV (3–0–0–1), 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 B: I 12 setae (ft, tc’, tc”, p’, p”, a’, a”, it’, it”, u’, u”, 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). One female lectotype and 1 paralectotype ( NHM no. 1966.2.22.106) from Agama lionotus lionotus Boulenger (Sauria: Agamidae ) ( NHM no. 1940.1.19.16–19), KENYA: Baringo district, near Lake Baringo, 19 January 1940, coll. V. E. Fusch.

Type material deposition. All material deposited in the NHM .

Hosts and distribution. This species was recorded from Agama lionotus lionotus from Kenya [Baringo district, near Lake Baringo] ( Jack 1962a) and from Agama caudospinosa from Kenya [between Maralal and Baragoi] ( Bertrand and Modry 2004).

Remarks: This species was originally described by Jack (1962a) as a subspecies of Pterygosoma annectans from Agama lionotus lionotus (Agamidae) i. e. P. annectans circularis . This study shows that morphological differences between P. annectans circularis and P. annectans allows the recognition of this subspecies as a distinct species. In Pterygosoma circularis the idiosoma is circular, setae dF are shorter than dG, about 85 pairs of the anterior dorsal setae are present, the peripheral setae are gathered in two distinct groups: medial and lateral, four pairs of the genital setae are present and pseudanal setae ps3 and p4 are apically expanded whereas in P. annectans the idiosoma is much wider than long, setae dF are slightly longer than dG, 50–60 pairs of the anterior dorsal setae are present, all peripheral setae are situated terminally, one to three pairs of genital setae are present and setae ps3 and ps4 are tapered or fine-pointed.

Moreover, examination of P. circularis reveals some inaccuracies in the original description ( Jack 1961). P. circularis has four genital setae (vs. three pairs in the original description), leg setae lGI are present and vFIV are absent (vs. setae lGI are absent and setae vFIV are present).

It is worth mentioning that Jack (1962a) described the species based on one ‘type specimen’ which should be considered as a holotype according to Article 73.1.1 of the International Code of Zoological Nomenclature (ICZN 1999, 2012). However, the examination of the type material in the NHM reveas existence of two specimens of the species designated as ‘syntype’ therefore the lectotype and paralectotype were designated .

In 2004 Bertrand and Modry described a new species, Pterygosoma livingstonei , from Agama caudospinosa Meek (Betrand and Modry 2004) . However, based on examination of the type material of P. livingstonei loaned from the MNHN I synonymize this species with species previously described by Jack (1961). In Bertrand and Modry’s (2004) species description the idiosoma is 455–600 long and 485–750 wide, seta vs ” of tarsi I is present, 3 genital setae are present and the palp tarsi formula is: 1–1–3–6. However, all this information is clearly wrong. All ‘type’ specimens of P. livingstonei loaned from the MNHN have idiosoma 850–890 long and 860–940 wide, seta vs” of tarsi I is absent, four genital setae are present and the palp tarsi formula is 1–1–3–4, which is also consistent with figure 7 presented in Bertrand and Modry (2004).

Figures

FIGURE 64. Pterygosoma circularis Jack, 1962, female in dorsal view.

FIGURE 65. Pterygosoma circularis Jack, 1962, female. A, ventral view; B, palp tarsus and palp tibia in dorsal view.