Arrenurus (Arrenurus) altomontanus, Smit, 2012

Smit, H., 2012, New records of the water mite family Arrenuridae from the Afrotropical region, with the description of 11 new species and two new subspecies (Acari: Hydrachnidia), Zootaxa 3187, pp. 1-31 : 2

Arrenurus (Arrenurus) altomontanus n. sp.

( Figs. 1–7)

Material examined. Holotype male, Hofchoo Lake , Dinsho, Bale Mountains, Ethiopia, 7° 07.247 N 39° 43.219 E, alt. 3051 m a.s.l., 26-x-2006 ( RMNH) . Paratypes: three males, seven females, same data as holotype ( RMNH) .

Diagnosis. Petiole simple, without ligulate process; hyaline membrane almost bilobed.

Description. Male: Idiosoma brownish, 984 (974–1012) long (including petiole) and 599 (608–616) wide. Anterior idiosoma margin concave. Dorsal shield incomplete, passing onto cauda, 348 (356–374) wide. One of the glandularia D1 lacking in the holotype, but present in paratypes. D3 combined to one, large hump. Cauda and pygal lobes distinct. Hyaline membrane with a deep concave posterior margin, resulting in an almost bilobed membrane. Petiole simple, widened at its base, ligulate process absent, in lateral view tip of petiole downturned. Setae associated with petiole shorter than petiole. Anterior coxal plates not extending to anterior idiosoma margin. Posterior margin of fourth coxal plates sloping. Gonopore 60 long. Genital plates relatively wide, extending to lateral idiosoma margin, lateral part slightly narrower. Lengths of PI–PV: 30, 77, 62, 94, 55; PII medially with six setae. Lengths of I-leg-4-6: 134, 128, 172. Lengths of IV-leg-4-6: 180, 120, 140; IV-leg-4 with a spur.

Female: Idiosoma brownish, 1085 (948–1110) long and 875 (786–907) wide, anterior margin slightly concave, posteriorly slightly truncated. Dorsal shield complete, 753 (632–729) long and 583 (527–567) wide. Anterior coxal plates not extending to anterior idiosoma margin. Medial margin of fourth coxal plates larger than medial margin of third coxal plates. Medial distance of fourth coxal plates a little bit larger than width of one genital valve. Gonopore 140 long and 154 wide, without sclerotized patches. Genital plates large and wide, less than two times as long as wide; genital field 591 wide. One paratype female has shorter genital plates ( Fig. 6). Lengths of PI–PV: 36, 86, 62, 98, 62; palp as in male, but PII medially with four setae. Lengths of I-leg-4-6: 146, 134, 130. Lengths of IV-leg-4- 6: 200, 184, 142.

Etymology. Named for its occurrence in the high mountains.

Remarks. Most important characteristic for the new species is the almost bilobed hyaline membrane. Two other Afrotropical species have also a simple petiole, i.e. A. cooki K.O. Viets, 1968 and A. capensis Thor, 1902 , but both species have a different hyaline membrane.