Pterygosoma aculeatum Lawrence, 1936

Fajfer, Monika, 2020, A systematic revision of the scale mite genus Pterygosoma Peters, 1849 (Acariformes: Pterygosomatidae), Zootaxa 4805 (1), pp. 1-147 : 93-95

Pterygosoma aculeatum Lawrence, 1936 ( Figs 83–85 ) new status

Pterygosoma aculeatum Lawrence, 1936: 25 , fig. 20

Pterygosoma agamae aculeatum Jack, 1962: 284 , fig. 21

Type host: Agama aculeata (Sauria: Agamidae ). Type locality: South Africa (Stydenburg).

Redescription. FEMALE (based on neotype and 9 specimens from type host species, Agama aculeata ). Gnathosoma . Chelicerae 200–225 long; slender distal part 115–135 long, basal swollen part 85–90 long. Fixed cheliceral digit spinous, 20–25 long. Setae dF and dG, 45–55 and 50–70 long, respectively. Palpal tibia with short claw; palpal tarsi with 3 setae. Subcapitulum with filiform setae n, 25–35 long. Peritremes 145–170 long. Hypostome 150–170 long, with smooth flattened apex. Idiosoma 515–655 long and 1095–1270 wide. Dorsum with 4 groups of setae: 75–88 pairs of antero-lateral serrate setae, 35–50 long; 2 pairs of dorso-median setae: dm1 slightly serrate and 50–65 long; dm2 slightly apically expanded and 85–115 long; 3–5 pairs of apically expanded postero-lateral setae, 90–125 long, and 26–32 pairs of tapered or apically expanded peripheral setae, 195–220 long, situated posteriorly. Eyes absent. Venter. Setae vm1 filiform, vm2 serrate, 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 20–25 long (sometimes setae g1 and g2 barely discernible). Setae g3 thicker than g1 and g2, 30–35 long. Pseudanal series represented by 5–6 pairs of paddle-shaped setae ps, 80–115 long. Legs chaetotaxy as in persicum group i. e. setae of trochanters I–IV (1–1–1–1), femora I–IV (3–1–1–1), genua I–IV (3–1–1–1), tibiae I–IV (5–3–3–3). All leg setae filiform, except for slightly serrate setae d’FI–IV. Setation of tarsi 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 setae a’, a”, u’, u”, vs’ of legs I–IV smooth.

MALE (based on description presented in Jack 1962b, amended). Gnathosoma as in female. Chelicerae about 110 long, swollen cheliceral part and slender distal part subequal in length, about 55 long. Idiosoma 460–670 long and 1070–1275. Dorsum with about 30 pairs of antero-lateral serrate setae, 35–70 long; 5 pairs of smooth finepointed setae situated postero-laterally, 150–220 long; 2 pairs of dorso-median setae dm1 and dm2: setae dm1 serrate and about 55 long, setae dm2 smooth and about 20 long; and 7–9 pairs of smooth fine-pointed setae, 210–230 long. Eyes present. Aedeagus about 150 long, directed forward; genito-anal opening with 2 pairs of filiform setae. Venter as in female. Legs I–IV as in female.

Type material (not examined). Six specimens from Agama aculeata Merrem (Sauria: Agamidae ), SOUTH AFRICA, Northern Cape Province, Strydenburg.

Type material deposition. All type material deposited in the SAM is lost (Dawn Larsen, personal communication).

Neotype (examined). Neotype female ( NHM no. 1966.2.22.59–68) from Agama aculeata ( NHM no. 1918.1.28.1), SOUTH AFRICA: Northern Cape Province, Kimberley , 28 January 1918, coll. J. H. Powell.

Non-type material (examined). Four females ( NHM no. 1966.2.22.59–68) from Agama aculeata ( NHM no. 1918.1.28.1), SOUTH AFRICA: Northern Cape Province, Kimberley , 28 January 1918, coll. J. H. Powell; 3 females ( NHM no.1966.2.22.34–43) from same host species ( NHM no. 1910.6.18.1.6), SOUTH AFRICA: Namaqualand , 18 June 1910, coll. Marloth; 2 females ( NHM no. 1966.2.22.47–54) from same host species ( NHM no. 1917.8.27.6), SOUTH AFRICA: Northern Cape Province, Modder River near Kimberley , 27 August 1917, coll. J. H. Powell.

Hosts and distribution. This species was recorded from Agama aculeata from South Africa [Stydenburg, Kimberley and Pretoria] and Namibia [Namaraland] ( Lawrence 1936); Agama armata and Agama kirkii both from Malawi ( Loveridge 1953).

Remarks. This species was considered as a subspecies of Pterygosoma agamae Peters, 1849 i.e. P. agamae aculeatum Jack, 1962 ( Jack 1962b) . However, the morphological differences found among specimens of P. agamae and P. agamae aculeatum allow the elevation of this subspecies to the species rank as originally was described by Lawrence (1936). In P. aculeatum setae vGI are present (vs. setae vGI are absent in P. agamae ), the hypostome has smooth flattened apex (vs. the hypostome has a small depression at the apex), the fixed cheliceral digit is spinous (vs. the fixed cheliceral digit has a long tine at the top), setae vm3 have discernible serration (vs. setae vm3 are smooth) and the eyes are absent (vs. the eyes are present).

In accordance with Article 75.3 of the International Code of Zoological Nomenclature (ICZN 1999, 2012) I designate one of the female specimens from Jack’s (1962b) study as a neotype of Pterygosoma aculeatum Lawrence, 1936 with the purpose of clarifying the taxonomic status of the species and present a redescription of the species above.

Figures

FIGURE 83. Pterygosoma aculeatum Lawrence, 1936, female in dorsal view.

FIGURE 84. Pterygosoma aculeatum Lawrence, 1936, female in ventral view.

FIGURE 85. Pterygosoma aculeatum Lawrence, 1936, female; details. A, part of gnathosoma in dorsal view; B, tarsus I in ventro-lateral view; C, tarsus II in dorso-lateral view.