Porolohmannella violacea ( Kramer, 1879 )

Abé, Hiroshi, 2021, Taxonomic review of the subfamily Lohmannellinae (Acari: Trombidiformes Halacaridae) with morphological comparisons among genera, Zootaxa 4980 (2), pp. 201-255 : 222-223

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]. Holstein, Behl (Behler See) and Sandkathen (Plön), Plöner See, Glashütte (Hamburg), Neuenburg, Thüringen, Schöhsee, Lützlower and Kleinower See (Uckermark), Möhringen, Falkau (Schwarzwald), Beuron, Ursee, Brege, Brigach, Seeon (Obing) [ Germany]. Maas River (Bergen), Herzogenbosch, St. Odiliënberg (Limburg), Pikmeeuwenwater (Hamert), Roer, St. Michielsgestel, Boxtel, Apeldoorn, Doetinchem, Zuidwolde, Noord Brabant, Maarsseveen [ Netherlands]. River Garvan, River Nevis, River Tilt, River Garry, River Tay, River Spey, River Moriston, River Almond, River Rothay, Epping Forest, Weybridge, Surrey, Cumbria, Malham Tarn, Isle of Man, West Yorkshire [ UK]. Duzos-Moûpa [ Belgium]. Lake Nino, Tavignano River ( Corsica), Lacs de l’Estibére (Pyrénées) [ France]. Statzersee (St. Moritz) [ Switzerland]. Lago di Mergozzo, Pallanza & Isola Madre (Lago Maggiore), Trentino-Alt Adige, Lago Calamone, Greppo, Lago Trasimeno, Manghisi (Sicilia) [ Italy]. Moosebruchs [Czech Rep.]. Lunz am See [ Austria]. Reinerz (Klodzko), Pešića Lake, Šiško Lake (Bjelasica Mt.) [ Montenegro]. Jezioro Ińsko (53°26’N, 15°32’E), Slask Dolny, Sudety Zachodnie, Beskidy Zachodnie, [ Poland]. Lake Balaton [ Hungary]. Danube Delta [ Ukraine]. Lake Sevan [ Armenia]. Karel’skaya Rep., Lake Kara-Kel, Teberda (Karachay-Cherkess Rep.), Lake Kuchak (Nizhnetavdinsky District in Tyumen), Yakutsk [ Russia]. Hokkaido [ Japan]. Nearctic Realm: Godthaab, Eqitsoq, Disko Is. ( Greenland) [ Denmark]. Tuktuyaktuk (Northwest Territories), Vancouver Island (British Columbia), Muskeg River (Alberta), Southern Indian Lake (Manitoba), Lake Opinicon, Georgian Bay (Ontario), Lake Matamec (Quebec), Avalon Peninsula (Newfoundland) [ Canada]. Pettaquamscutt (Rhode Island), Mirror Lake (New Hampshire), Tupper Lake (Franklin County), Dutchess, Ulster, Wappinger Creek (New York) [ USA].

References. Abé (1990b), André (1935), Angelier (1951, 1952, 1953b, 1953 c, 1954, 1959a –d, 1965), Bartsch (1981b, c, 1982a, 1987, 1988c, 1989a, c, 1996a, 2004b, 2006a, 2007b, 2011), Bazan-Strzelecka (1972), Beier (1928), Berg & Petersen (1956), Borner (1917), Brehm (1926), Buitendijk (1945), Chatterjee & Durucan (2021), Cicolani & Di Sabatino (1985), Cooreman (1954), Davids et al. (1994), Friedman (1950), Gerecke (2015), Gessner (1931, 1953), Gledhill (1973, 1974, 1982), Gledhill & Viets, K.O. (1976), Green (1956), Green & Macquitty (1987), Hallas (1978), Harnish (1924, 1926), Husmann & Teschner (1970), Kautsky et al. (1981), Keiding (1943), Konnerth-Ionescu (1981), Kramer (1879), Lettevall (1962), Lohmann (1889, 1901, 1907b), Lukin (1929), Lundblad (1920, 1926), Macer (1899), Mari & Morselli (1985, 1992), Meuche (1939), Migot (1926), Müller-Liebenau (1956), Nocentini (1961), Obermayer (1922), Paasivirta (1975), Pešić (2004b), Petrova (1973, 1974, 1984), Peus (1932), Ponyi (1965), Ramazzotti & Nocentini (1960), Romijn (1920, 1921), Ruffo (1961), Semenchenko et al. (2010), Schwoerbel (1955, 1956, 1961a, b, 1962, 1964a, 1964b), Smit et al. (2010), Soar (1924), Sokolov (1927, 1940, 1952) Sokolov & Yankovskaya (1962), Stirnimann (1926), Stolbov et al. (2018), Strayer (1985, 1988), Svenonius (1951), Szalay (1964, 1970), Teschner (1988), Thor (1914), Trouessart (1889a), Viets, K. (1923, 1924a, b, 1926, 1927a, b, d, 1928b, d, 1933, 1936, 1938, 1939b, 1949), Viets, K.O. (1956a, b, 1958, 1967), Viets, K & Viets K. O. (1960), Wainstein (1967), Walter (1914, 1917, 1919, 1922), Wesenberg-Lund (1939), Widbom (1977), Wiszniewski (1939), Yankovskaya (1965), Zawal (1998).

Depository. Unknown.