Thoracophoracarus (Thoracophorurus) petioluriger K. Viets, 1925

Smit, Harry, 2021, Water mites from West Africa (Acari: Hydrachnidia), Acarologia 61 (3), pp. 700-746 : 742-743

Thoracophoracarus (Thoracophorurus) petioluriger K. Viets, 1925

( Figure 26 A-C)

New record. Ghana. 0/1/0, unnamed stream upstream Sagyimase, Atewa Hills, 6°13.966′

N 0°33.114′ W, 671 m a.s.l., 28 Feb. 2013.

Description. Female: Idiosoma colour brownish. Idiosoma dorsally 514 long and 381 wide, ventrally 502 long. Anterior idiosoma margin strongly concave, excretory pore terminal lying in a concave posterior idiosoma margin. Glandularia tubercles in posterior half of dorsum large ( Figure 26A ). All suture lines of the coxae indistinct. Gonopore field 90 long, genital plates very indistinct and hardly discernible ( Figure 26B ). Length of P1–5: 18, 42, 30, 50, 22. P2 medially with three setae, P4 anteroventrally pointed ( Figure 26C ). Length of I-leg-4–6: 104, 104, 92. Length of IV-leg-4–6: 80, 84, 70. Swimming setae: III-leg-3 two, III-leg-4 four, III-leg-5 four, IV-leg-2 and -3 one, IV-leg-4 four, IV-leg-5 four.

Remarks. As stated by Gerecke (2009), attribution of males and females in arrenurids can be problematic due to the strong sexual dimorphism. This applies to the specimen of this study also. Based on the strong concave anterior margin, assignment T to. whartoni Cook,

1966 would be most likely. However, due to the relative slender P4 and the large humps of the dorsum, I assigned this specimen to A. petioluriger . Females of the latter species, originally described as T. mammosus K. Viets, 1925 , are known from two specimens only collected in Cameroon. Moreover, there are some differences with the description given by Gerecke (2009), i.e., the anterior margin is stronger concave and the dorsum has two more pairs of glandularia. Therefore, an emended description is given of the female petioluriger of.

Distribution. Cameroon (K. Viets 1925), Ghana (this study).

Figures

Figure 26 Thoracophoracarus(Thoracophorurus) petioluriger K. Viets, female. A – dorsum; B – venter; C – palp. Scale bars: A-B 100 µm, C = 50 µm.