Limnohalacarus wackeri ( Walter, 1914 )

Durucan, Furkan, 2020, Two new genera, Limnohalacarus and Soldanellonyx (Acari: Halacaridae) in freshwater halacarid mites with additional new records from Turkey, Persian Journal of Acarology 9 (1), pp. 1-11 : 5

Limnohalacarus wackeri ( Walter, 1914)

( Figs. 4 A–F, 5)

Material examined

1 ♂, standing water, on sediments and stones, Lake Eğirdir-Isparta , 19 August 2019, coll. F. Durucan.

Morphology and notes

Idiosoma 390 long, 263 wide. AD 82 long, 100 wide. OC divided transversely with cornea and eye pigment. Anterior ocular plate is wider than long. OC 37 long, 61 wide. Post ocular plate slender, triangular 42 long, 25 wide. Pore canaliculi in the distal part of the OC. Setae ds-1 on AD, ds-2 striated in integument, ds-3 on PD. Dorsum with five pairs of gland pores ( Fig. 4A ). AE with 3 pairs of ventral setae. AE 110 long, 230 wide. PE with one seta dorsally, one laterally. PE 135 long, 63 wide. PD 300 long, 153 wide, 1.9 times longer than wide and anteriorly rounded. GA 217 long, 175 wide. The specimen has 50 pairs of perigenital setae and 7 pairs of genital acetabula ( Fig. 4B ). Dorsal plates AD, OC and PD reticulated ( Fig. 4C ). Gnathosoma 93 long, 75 wide, length:width ratio 1.24. First pair of maxillary setae in. Second palp is broadly, basal spur. Palps with four segments, attached dorsally. P-1, 8, short. P-2, 45, enlarged. P-3, 20 and P-4, 35. P-2 with one short and one long seta. P-3 has a spine ventromedially. P-4 with six setae and a large spine ( Figs. 4D & E ). Leg-I chaetotaxy from trochanter to tarsus: 1, 4, 4, 7, 8, 7. Claws on tarsus I with pectines ( Fig. 4F ). As mentioned by Bartsch (2006) egg-shaped internal concrement (ic) has observed in the author's species as shown in Figure 5 .

This is the first report of this genus and species from Turkey. The morphological characteristics and habitat preferences of the specimens reported here accord with the previous descriptions given by Bartsch (1989, 2001).

Distribution

The genus has a worldwide distribution. At present the genus Limnohalacarus contains 13 described species. Limnohalacarus wackeri is recorded from northern European and Asian waters, from southern Finland and Kamchatka ( Bartsch 2001, 2018). Present record: Lake Eğirdir (Isparta).

Figures

Figure 4. Limnohalacarus wackeri (Walter, 1914) (male) – A. Idiosoma, dorsal view; B idiosoma, ventral view; C. reticulation on the plates; D. Gnathosoma, ventral view; E. Palp, lateral view; F. Leg I, medial view. Scale bars: 100 µm.

Figure 5. Limnohalacarus wackeri (Walter, 1914) (male) – ic = internal concrement.