Limnohalacarus Walter, 1917

Bartsch, Ilse, 2015, The genital area of Halacaridae (Acari), life stages and development of morphological characters and implication on the classification, Zootaxa 3919 (2), pp. 201-259 : 222

Limnohalacarus Walter, 1917

Type species. Halacarus wackeri Walter, 1914 .

Adults. In female genital- and anal plate contiguous or partly fused. Female GO near posterior margin of genital plate and covered by large genital sclerites. Acetabula in external position; arranged along lateral margins of genital plate; 4–12 pairs present. Female with three to ten pairs of slender pgs and one to four pairs of sgs; GO in subterminal position ( Bartsch 2006c: fig. 5-15b). Ovipositor short and slender. Genital spines delicate, short and spiniform; number not known. In male GP and AP fused. Arrangement of external acetabula same as in female. Male GO much smaller than in female and in a ventral position ( Bartsch 2006c: fig. 5-15c). Perigenital setae slender, 17–30 pairs surrounding GO. Genital sclerites with three pairs of small subgenital setae. AE in both female and male with epimeral pores.

Juveniles. With two nymphal stages, deutonymph and protonymph. In both nymphs GP and AP fused. Genitoanal plate of deutonymph with two to six pairs of pgs; zero to two pairs of sgs and three to eight pairs of external gac, the latter arranged as in adults. Protonymph with two to three pairs of gac; pgs and sgs lacking. Larva with pair of large epimeral pores ( Bartsch 2013a: fig. 2f).

Remarks. Limnohalacarus is a cosmopolitan genus; slightly more than a dozen species have been described ( Bartsch 2013a). The females do not deposit the eggs in the substratum inhabited but attach them to the hind legs. This way of egg deposition may be correlated with a reduction of the genital spines.