Hygrobates (Hygrobates) dentipalpis, Smit, 2021

Smit, Harry, 2021, Water mites from West Africa (Acari: Hydrachnidia), Acarologia 61 (3), pp. 700-746 : 711-713

Hygrobates (Hygrobates) dentipalpis n. sp.

Zoobank: 6229E1E4-B4C7-4E31-B803-60971D506602 ( Figure 6 A-C)

Material examined. Holotype male, stream Asukuma , Kakum National Park, Ghana, 5°26.995′ N 1°25.071′ W, 131 m a.s.l., 12 Feb. 2013 ( RMNH) . Paratypes: One male, same data as holotype ( RMNH); 1/0/0, Supon stream near Asiakwa, Atewa Hills, Ghana, 6°15.530′ N 0°30.642′ W, 250 m a.s.l., 7 Mar. 2011 ( RMNH); 1/0/0, River Tordzi, 6°32.819′ N 0°41.445′

E, 79 m a.s.l., 19 Feb. 2013 ; 1/0/0, Kue River, Kyabobo NP, Ghana, 8°31.087′ N 0°36.049′ E,

208 m a.s.l., 25 Feb. 2013 ( RMNH).

Material for comparison. Hygrobates sudafricanus K.O. Viets, 1963 : male, Klein Vaal River near source, Südafrika, Val. 857, Chütter leg., 11 Nov. 1959 (slide 51656, SMF); female, Klein Vaal River near source, Südafrika, Val. 857, Chütter leg., 11 Nov. 1959 (slide 51657, SMF); male, Klein Vaal River near source, Südafrika, Val. 857, Chütter leg., 11 Nov. 1959 (slide 51658, SMF); female, Klein Vaal River near source, Südafrika, Val. 857, Chütter leg., 11 Nov. 1959 (slide 51660, SMF).

Diagnosis. Anterior coxae only slightly tapering posteriorly; genital field with three pairs of acetabula; P2 with an anteroventral extension with several denticles, P3 with several relatively large denticles.

Description. Male. Integument finely lineated, only visible at higher magnification. Idiosoma dorsally 446 (360-413) long and 369 (300-356) wide, ventrally 486 (405-454)

long. Dorsum without platelets. Anterior coxae only slightly tapering posteriorly. Cx-I fused medially. Suture line Cx-III/IV incomplete, Cxgl-4 located near this suture line, Cx-IV rounded medially ( Figure 6A ). Genital field 102 long and 112 wide, with three pairs of acetabula in a triangle; gonopore 64 long. Length of P1–5: 20, 78, 50, 116, 41. P2 with an anteroventral extension with several small denticles, a few denticles present posterior to this extension, but these only visible in ventral view. P3 ventrally with four relatively large denticles, medially with a few more denticles. P4 slender ( Figure 6B ). Length of I-leg-4–6: 103, 104, 72. I-leg-5 distally with two setae, one of these slightly bowed ( Figure 6C ). Length of IV-leg-4-6: 136, 154, 124. Legs without swimming setae.

Female: Unknown.

Etymology. Named for the presence of relatively large denticles on P3.

Remarks. The new species is similar to H. niloticus Walter, 1922 in the presence of an anteroventral extension of P2, with several denticles on this extension. However, H. niloticus has strongly tapering anterior coxae. Males of Hygrobates sudafricanus K.O. Viets, 1963

from South Africa, have P3 with 5–6 smaller denticles, P2 has a less extending anteroventral extension with larger and fewer denticles (about 2–3), in the new species there are about 6–7 small denticles on the anteroventral extension. Females of H. sudafricanus have P2 with a larger anteroventral extension and P3 with larger denticles, but the female of the new species is unknown.

Figures

Figure 6 Hygrobates(Hygrobates) dentipalpis n. sp., holotype male. A – venter; B – palp; C – I-leg-4–6. Scale bars: A = 100 µm, B-C = 50 µm.