Lohmannella Trouessart, 1901

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 : 223

Lohmannella Trouessart, 1901

(Fig. 61)

Type species. Leptognathus falcatus Hodge, 1863 .

Adults. In female and male GP and AP fused. Female GO same or somewhat larger than that of male, in both GO generally in almost similar position. Female GA of marine species with three pairs of internal gac, these often rather small, rarely large ( Viets 1939a: fig. 7; Bartsch 1986d: fig. 19). Females of freshwater species with two pairs of external acetabula in posterior part of genital sclerites ( Petrova 1969: figs 2b, 5b). Female GA with 6–37 pairs of slender pgs; each genital sclerite with four subgenital setae. Ovipositor short, with 12 genital spines, one basal and five apical pairs, the latter in 2+3 arrangement (two anterior and three posterior pairs). Genital spines of L. gaussi Lohmann, 1907 similar-sized, palmate, each ending with numerous tines ( Bartsch 1979a: fig. 29). Male GA with 25–40 pairs of slender pgs, these arranged densely around GO. Each genital sclerite with four short sgs. Genital acetabula in general small, three pairs adjacent in posterior part of GO ( Viets 1939a: fig. 8; Bartsch 2005b: fig. 1D). In a few freshwater inhabiting species acetabula external, situated on genital sclerites ( Petrova 1969: figs 1b, 4b). Adults without epimeral pores.

Juveniles. With a larval and two nymphal instars. In deuto- and protonymph GP separated from AP. Deutonymphal GP with two to five pairs of pgs, two pairs of sgs and two pairs of internal gac ( Imamura 1968: fig. 5; Bartsch 1979a: fig. 37, 2005a: fig. 36, 2005b: fig. 2F). Protonymph with a pair of internal acetabula and, immediately posterior to the level of acetabula, with a single pair of small setae close to primordial genital slit (Fig. 61); no further setae present. Larva with tube-like epimeral pores ( Bartsch 2007b: fig. 10C).

Remarks. Thirty-one species are known from marine habitats, another five have been found in fresh and low salinity brackish water areas. The marine species are spread world-wide and inhabit all depth zones from the low water edge to the deep sea ( Bartsch 2009a). Records of the freshwater species are from the circum-Mediterranean, from areas once being adjacent or covered by the Paratethys ( Bartsch 1996g)