Arrenurus mansoensis, Smit, 2020

Smit, Harry, 2020, New records of the water mite genus Arrenurus Dugès, 1834 from South America (Acari: Hydrachnidia: Arrenuridae), with the description of five new species and one new subspecies, Acarologia 60 (2), pp. 371-389 : 379-380

Arrenurus mansoensis n. sp.

Zoobank: B5945CB6-D357-4ED4-BF63-9D9191F4CE43

( Figure 6 )

Material examined — Holotype male, Manso River , Nahuel Huapi National Park, Río Negro Province, Argentina, 41°20.858 S 71°36.300 W, alt. 817 m asl, 17-ii-2018 ( MBR).

Diagnosis — Male: Cauda relatively short, Lgl-4 on small humps, posterior margin of cauda convex, P2 with a large patch of setae.

Description — Idiosoma yellowish, dorsally 754 long and 599 wide, ventrally 786 long. Dorsal shield incomplete, 421 wide, distance dorsal shield – anterior idiosoma margin 182. Cauda distinctly set off from anterior idiosoma with Lgl-4 on small humps, posterior margin convex. Gonopore 52 long, genital field 454 wide, relatively broad, not extending to lateral idiosoma margin. Lengths of P1-5: 38, 70, 48, 72, 26. P2 with a large patch of setae, the setae of the anterior row larger than the more posterior setae; near dorsal margin two long setae and one smaller seta. Length of I-leg-4-6: 110, 114, 100. Length of IV-leg-4-6: 146, 192, 190. Legs with numerous swimming setae.

Etymology — Named after the type locality, the Manso River.

Remarks — The new species is close to Arrenurus neuquenensis Rosso de Ferradás, 1987 .

The latter species is larger (842-909) and has a shorter and broader cauda, especially the part posterior to the humps of Lgl-4. Moreover, the idiosoma of the new species is more elongated compared to A. neuquenensis .

Figures

Figure 6 Arrenurus mansoensis n. sp., holotype male. A – dorsum; B – venter; C – palp. Scale bars: A, B = 100 µm, C = 50 µm.