Porolohmannella violacea

• Main Author: Abé, Hiroshi
• Format: Other/Unknown Material
• Language: unknown
• Published: 2021
• Subjects: Biodiversity; Taxonomy; Animalia; Arthropoda; Arachnida; Trombidiformes; Halacaridae; Porolohmannella; Porolohmannella violacea; Norway; Seta; Kramer; Pääjärvi; Luleå
• Online Access: https://zenodo.org/record/4889580; https://doi.org/10.5281/zenodo.4889580

Porolohmannella violacea (Kramer, 1879) Diagnosis. One cornea present. Glp-1 anterior to Ds-1. Ds-2 on OC. Ds-3 on OC. One dorsal seta on PE. Female with 6 Pgs and no Sgs. Tr I–IV with (0,1)-1-1-0 setae; Bf I–IV with 2-2-2-2 setae; Tf I–IV with 4-4-3-3 setae; Gn I–IV with 6-6-3-3 setae, (1,2)-1-0-0 Bp setae; Tb I–IV with 8-8-7-(6,7) setae, 4-(3,4)-3-3 Bp setae; Ta I–IV with 3-3-4-3 dorsal setae, 0-0-0-0 Bp setae. Lc I with accessory process and fine comb. Idiosoma length 475–580 in female, 405–449 in DN, 315–324 in PN, 265 in LV. Idiosoma width 307–370 in female, 240–308 in DN, 195–204 in PN, 165 in LV. Gnathosoma length 245–330 in female, 195 in DN. Ratio of gnathosoma to idiosoma 0.47–0.52 in female, 0.48 in DN; Ratio of P-2 to P-1 2.81–3.18. Remarks. This is the single species belonging to the genus Porolohmannella. The species was originally described by Kramer (1879) under the name of Leptognathus violaceus. Raphignathus falcatus (e.g., Macer 1899), Trouessartella violacea (e.g., Lohmann 1901) and Lohmannella violacea (e.g., Lohmann 1907b) correspond to this species. The species is similar to species in the genus Lohmannella, however, easily distinguishable by its PE with 3 pairs of setae, Sgs absent, and P-2 with a single seta. Female, DN, PN, and LV are known. Male is unknown, though many reports have been given from all over the world. Habitat. Inland freshwater and rarely brackishwater: Detritus in river, lake, pond, swamp, and bog (peat bog). Interstices of gravels and coarse sands, stony and rocky bottom at a depth of 0–40 m, gill chambers of crayfish (Potamobius astacus), colonies of freshwater ectoproct, Plumatella. Sphagnum and Fontinalis (moss) growths. Potamogeton lucens (vascular plant), Cladophora spp. (Chlorophyta), 0–1810 m alt. Distribution. Palearctic Realm: Oslo [Norway]. Luleå, See Erken, Kristineholm, Estuna, Torsby, Bohuslän, Bokenäs, Essvik, Uppland, Lohärad, Malmö [Sweden]. Lake Pääjärvi [Finland]. Seda (57°40’N, 25°45’E) [Latvia]. St. Hulsø, Store Gribsø, Madum Lake, Møen [Denmark]. ...