Arrenurus (Megaluracarus) chutteri ankasa

Smit, Harry, 2021, Water mites from West Africa (Acari: Hydrachnidia), Acarologia 61 (3), pp. 700-746 : 736-738

Arrenurus (Megaluracarus) chutteri ankasa n. sp.

Zoobank: 13821AE5-C70B-4DE4-BAF2-2758B7386E92

( Figure 23 A-D)

Material examined. Holotype male, Second pond, Ankasa NP, Ghana, 5°17.424′ N 2°38.286′ W, 58 m a.s.l., 14 Feb. 2013 ( RMNH) . Paratypes: one male, one female, same data as holotype ( RMNH).

Diagnosis. Cauda of male expanding laterally, posterior margin of cauda with a relatively wide median cleft which is widening posteriorly.

Description. Male: Idiosoma greenish, dorsally 838 (867) long and 502 (494) wide, ventrally 838 (851) long. Dorsal shield 360 wide. Anterior idiosoma margin convex. Lateral idiosoma margin bulging anterior to the position where the genital plates extend onto the lateral part of the idiosoma. Cauda expanding posterolaterally, in dorsal view lateral margins of cauda concave ( Figure 23A ). Posterior margin of cauda with a relatively wide median cleft which is widening posteriorly; lateral to cleft a pair of small setae. Dgl-4 lying in an area with spiny setae. Gonopore 52 long. Genital plates long, extending onto lateral margins of idiosoma ( Figure 23B ). Length of P1–5: 24, 56, 30, 60, 30. P2 medially with three setae ( Figure 23C ). Length of I-leg-4–6: 108, 110, 112. Length of IV-leg-4–6: 170, 138, 146. IV-leg-4 with a short spur, IV-leg-6 slightly bowed. Third and fourth legs with numerous swimming setae.

Female: Idiosoma dorsally 713 long and 567 wide, ventrally 721 long. Dorsal shield complete, 543 long and 413 wide. Anterior coxae extending beyond anterior idiosoma margin. Medial margin of Cx-IV longer than medial margin of Cx-III. Medial distance of Cx-IV smaller than width of one genital valve. Gonopore field 148 wide, with anteriorly and posteriorly a small band of sclerotized patches; gonopore 92 long. Genital plates long and narrow, extending to lateral idiosoma margin ( Figure 23D ). Length of P1–5: 27, 56, 26, 66, 34. P2 medially with four setae. Length of I-leg-4–6: 104, 104, 92. Length of IV-lg-4–6: 130, 140, 118. Third and fourth legs with numerous swimming setae.

Etymology. Named after Ankasa National Park, the name is a noun in apposition.

Remarks. The male of the new species differs from A. chutteri K.O. Viets, 1966 and A. chutteri longipes Smit, 2012 in a much more laterally expanding posterior part of the cauda. The female of A. chutteri has shorter genital plates, not extending to the lateral idiosoma margin. The female of A. chutteri longipes has undulating genital plates.

Figures

Figure 23 Arrenurus (Megaluracarus) chutteri ankasan. sp., holotype male A-C, paratype female D. A – dorsum; B – venter; C – palp; D - venter. Scale bars: A-B, D = 200 µm, C = 50 µm.