Unionicola neowalkeri, Orginal, 2021

Orginal, Harry Smit, 2021, The water mites of Western Australia (Acari: Hydrachnidia), with the description of 13 new species, Acarologia 61 (4), pp. 928-966 : 952-954

Unionicola neowalkeri n. sp.

Zoobank: EB7278D5-5B80-4FEC-9537-FC0E65F397D3

( Figure 14 A-C)

Material examined — Holotype female, Kent River at crossing with South Coast Highway, from mussel Westralunio carteri Iredale, 1934 (Hyriidae) , Western Australia, Australia, 34°57.576′ S 117°02.430′ E, 19 Apr. 2008 ( WAM).

Diagnosis — Genital field with two pairs of platelets, each platelet with three acetabula and a stout seta; P4 stocky, only I-leg-6 with an anterodorsal spatulate seta.

Description — Female: Idiosoma dorsally 624 long and 445 wide, ventrally 648 long.

Dorsum with two pairs of platelets, anterior pair 50 long, posterior pair of similar size. Coxal area 380 long. Apodemes of anterior coxae short. Suture line of Cx-III/IV incomplete, posterior margin of Cx-IV with a well-developed projection. Genital field terminal, with two pairs of platelets, each platelet with three acetabula. Anterior platelets with a relatively short posterior extension with a stout seta. Each platelet with two fine setae ( Figure 14A). Length of P1-5: 8, 94, 40, 90, 54. P1 short, P2 medially with two setae, P4 stocky, P5 with two claws ( Figure 14B).

Length of I-leg-4-6: 98, 86, 104. I-leg-6 enlarged, with an anterodorsal spatulate seta, I-leg-5 with two stout setae ( Figure 14C). Other legs without a spatulate seta. Length of IV-leg-4-6: 144, 154, 128. Legs without true swimming setae, but several long, stiff setae present on fourth and fifth segments.

Male: Unknown.

Etymology — Named for its resemblance to U. walkeri K.O. Viets, 1980.

Remarks — The species is close to U. walkeri (in parentheses walkeri), but differs in six pairs of acetabula (five pairs), I-leg-5 with two stout setae (five), P4 stocky (less stocky), only first leg with a spatulate seta (all legs). From the same mussel species in SW-Australia, another

Unionicola species is known, i.e. U. assimilis K.O. Viets, 1980 (see K.O. Viets 1980). The latter species has the anterior platelets with a long posterior extension without a stout seta, the dorsum with a pair of elongated platelets and P4 is less stocky.