Arrenurus (Arrenurus) dugesi, Smit & Pesic, 2010

Smit, H. & Pesic, V., 2010, New Species Of Water Mites From Oman, With Some Zoogeographical Notes (Acari: Hydrachnidia), Acarologia 50 (2), pp. 151-195 : 186-189

Arrenurus (Arrenurus) dugesi n. sp.

( Figures 29 A-F)

Type material — Holotype male, Wadi Hanna , Oman, 17°03.236 N 54°36.489 E, 4-xi-2008 . Paratypes: 12/8/0, same data as holotype.

Diagnosis — Male: cauda short; pygal lobes distinct; hyaline membrane with pointed angles; petiole rounded posteriorly; ligulate process of petiole rounded, lying well distanced from posterior margin of petiole. Female: Genital plates short, tapering laterally, sloping towards posterolateral idiosoma margin.

Description

Male — Idiosoma greenish, L (including petiole) 1073 (932-1154), W 802 (701-850), posterior margin slightly concave. D1 on small humps. Dorsal shield ( Fig. 29A ) W 437 (397-486). Cauda short, pygal lobes distinct. Hyaline membrane with pointed angles, posterior margin concave. Petiole ( Fig. 29C ) rounded posteriorly, ligulate process rounded, well distanced from posterior margin of petiole, uplifted only slightly. Petiole ventrally with two lateral rows of irregularly shaped denticles. Setae associated with petiole bifurcated, these setae longer than petiole. Cx-I not extending to anterior idiosoma margin ( Fig. 29B ). Gonopore L 58. Genital plates narrow, extending to lateral idiosoma margin. Palp ( Fig. 29E ): total L 364; L: P-1, 40; P-2, 94; P-3, 70; P-4, 100; P-5, 60; P-2 with two setae in anteroventral corner and two medial setae more anterodorsally. L of I-Leg-4-6: 190, 186, 176. L of IV-Leg-4-6: 316, 114, 124; IV-Leg-4 with a long spur. Claws of legs with a

Acarologia 50(2): 151–195 (2010)

clawlet as large as claw, third and fourth legs with numerous swimming setae.

Females — Idiosoma greenish-brownish, L 1045 (948-1175), W 932 (850-1037). Anterior margin of idiosoma straight, posterolateral corners of idiosoma indistinct. Dorsal shield complete, L 664 (599-774), W 543 (494-616). D1 on small humps, setae of D4 long. Cx-I plates extending beyond anterior margin of idiosoma. Medial margin of Cx-IV longer than medial margin of Cx-III. Medial distance of Cx- IV shorter than width of one genital valve. Gonopore L 164, width of gonopore 186, genital valves with small sclerotized patches. Genital plates short, shorter than width of gonopore, sloping towards posterolateral idiosoma margin ( Fig. 29F ). Palp: total L 330; L: P-1, 32; P-2, 92; P-3, 62; P-4, 92; P-5, 52; P-2 with two anteromedial setae and two setae located more anterodorsally. L of I-Leg-4-6: 195, 160, 148. L of IV-Leg-4-6: 230, 182, 160. Claws of legs with a clawlet as large as claw, third and fourth legs with numerous swimming setae.

Etymology — Named after the French acarologist Antoine-Louis Delsecautz DugŁs (1797-1838), who erected the genus Arrenurus .

Remarks — Two Arrenurus species having also a petiole with a row of ventral teeth differ as follows: A. glenifferensis Lundblad, 1941 from southern Africa has a long cauda and a triangular ligulate process, A. denticulatus Mota¸s, 1927 from the Western Palaearctic has also a long cauda and a more angular-shaped petiole and ligulate process. The assignment of the female is uncertain, as two types of the females were collected on the type locality. The most common of these have been assigned to the new species, the less common to A. ortali Smit (see below). Moreover, the females here assigned to A. ortali Smit share with males of the same number and arrangement of medial setae on P-2.

Figures

FIGURE 29: Arrenurus dugesi n. sp. (A-E: male, F: female): (A) – idiosoma, dorsal view; (B, F) – idiosoma, ventral view; (C) – petiole, ventral view; (D) – petiole, lateral view; (E) – palp. Scale bars = 200 µm (A-B, F), 50 µm (C-E).