Unionicola boonsaengi, Smit, 2017

Smit, Harry, 2017, New records of water mites from standing waters in Thailand, with the description of nine new species (Acari: Hydrachnidia), Zootaxa 4312 (1), pp. 69-91 : 75

Unionicola (?) boonsaengi n. sp.

( Fig. 4 )

Material examined. Holotype female, Huay Tubtan Dam, Sisaket Province, Thailand, 15° 2.865ʹ N, 104° 1.362ʹ E, 9-ii-2011 ( RMNH).

Diagnosis. Palp stocky, P4 with three large ventral setal tubercles located posteroventrally, P5 with five stout terminal setae; leg segments thin, with relatively short grooved setae.

Description. Female: Idiosoma 551 long; 413 wide. Genital field with two pairs of platelets, anterior platelets with two acetabula (but difficult to see in the illustration due to folding of the integument), posterior pair with three acetabula in a line. Lengths of P1-5: 28, 99, 44, 98, 14. P2 with one long and three short pectinate setae, P3 with one anterodorsal and one anteromedial pectinate setae, P4 with one posteromedial thin seta and three large posteroventral setal tubercles, P5 with five stout terminal setae. Length of I-leg-4–6: 172, 178, 132. Length of IVleg-4–6: 182, 244, 226. Grooved or fluted leg setae small and thin. III-leg-5 and IV-leg-5 with three swimming setae.

Male: Unknown.

Etymology. The species is named in honour of Prof. Dr. Vichai Boonsaeng (Mahidol University, Thailand) for his support to biodiversity research in Thailand in the program of The National Research Universities and The Higher Education Research Promotion (NRU-HERP), Office of the Higher Education Commission.

Remarks. As we have collected a female only of the new species, we refrain from a subgeneric assignment. The combination of stout distal setae of P5 and large, posteroventrally located setal tubercles is unique and not found in any other Unionicola species. Moreover, the absence of grooved setae of the legs is characteristic also.

Figures

FIGURE 4. Unionicola boonsaengi n. sp., holotype female. A = venter; B = Gnathosoma and palp; C = I-leg- 4 – 6; D = IV-leg- 4 – 6. Scale bars = 50 µm.