Zerconidae

Abstract: The holotrichous condition for the idiosomal chaetotaxy of Zerconidae is reviewed. Using ontogenetic patterns of body setation of holotrichous taxa in other families of Gamasina for comparison, the homologies and notation for some of the podonotal and opisthosomal setae of zerconid mites are changed. These modifications lead to new interpretation of some of the apomorphic attributes used to characterize the family Zerconidae and superfamily Zerconoidea. The caudodorsal displacement of a pair of opisthogastric setae, JV5, so as to appear to be captured by the opisthonotal shield in deutonymphs and adults, is seen to be a unique characteristic of Zerconoidea. The caudal coalescence of the opisthonotal and opisthogastric shields, and the anterior displacement of setae J5 to a nearly transverse alignment with setae Z4 well ahead of the caudal body margin, characterize Zerconidae.

Abstract: Analysis has been completed of all the available material on gamasid mites from insular and continental territories of the Barents Sea region A total of 116 species has been revealed, including 9 new to science The species Gamasus armatus L Koch, 1879 is transferred to the genus Gamasodes Oudemans, 1939, thus becoming Gamasodesarmatus (L Koch, 1879), comb n Six species of gamasid mites occur even at the thermal limit in the Northern Hemisphere, on the ice-free grounds of Franz Josef Land (with mid-July temperatures ranging from −12°C to +16°C) On Svalbard, 25 species have been recorded, as compared to 27 on Novaya Zemlya, 39 on Vaigach Island, 43 on Kolguev Island, 50 in the Pechora Bay, 37 on Kanin Peninsula, and 58 on the Eastern Murman coast Despite the differences in the quality and quantity of material obtained during 30 years from numerous collectors, a relation between species diversity and summer heat supply has been revealed (linear regression coefficient: 0816; significance level: 99%) The most diverse families are Ascidae (23 species, including 20 species of Arctoseius), Parasitidae (15, including 6 species of Vulgarogamasus), and Zerconidae (14, including 11 species of Zercon) The species Zercon michaeli Halaskova, 1977, Zercon solenites Haarlov, 1942, Parasitellus papei (Karg, 1985), Parasitellus arcticus (Karg, 1985), and Halolaelaps gerlachi Hirschmann, 1966 have been recorded in Russia for the first time The species Zercon acanticus Blaszak, 1978, Poecilochirus nordi Davydova, 1971, Euryparasitus tori Davydova, 1970, Gamasellus tundriensis Davydova, 1982, Arctoseius nikolskyi Makarova et Petrova, 1992, and Neoseiulus ellesmerei (Chant et Hansell, 1971) are new to the European list The specific gamasid mites associated with lemmings or bumble-bees are absent on Franz Josef Land and Svalbard, since both archipelagoes were almost completely glaciated in the Late Pleistocene An obviously temporary population of a member of the family Macrochelidae, namely, of the dung-compost cosmopolitan species Macrocheles muscaedomesticae (Scopoli, 1772) was first recorded in the High Arctic (Spitsbergen) Distribution ranges of many species, mainly of those of the genus Arctoseius, lie within the Metaarctic (sensu Yurtsev, 1977) High Arctic patterns have been confirmed for Arctoseius tschernovi Makarova, 2000, A babenkoi Makarova, 2000, A productus Makarova, 2000, Neoseiulus sp aff tibielingmiut (Chant et Hansell, 1971) However, quite a few of the species traditionally considered as “arctic” and inhabiting mainly arctic landscapes in North America and the western Palaearctic, have also been found in the Siberian mountains as far southwards as the Altai-Sayan mountain system: Antennoseius oudemansi (Thor, 1930), Proctolaelaps parvanalis (Thor, 1930), Zerconopsis labradorensis Evans et Hyatt, 1960, Zerconmichaeli, Zercon solenites, etc Similar arcto-montane patterns have also been revealed for some “mountain” species: Trachytes hirschmanni Hutu, 1973, Syskenozercon kosiri Athias-Henriot, 1976, Veigaia belovae Davydova, 1979, Iphidinychus gaieri (Schweizer, 1961), and Zercon spp As the climate becomes milder, the total share of arctic and arcto-montane species in the individual regions of the European Arctic gradually drops from 100% (Franz Josef Land) to 12% (Eastern Murman coast)

Abstract: According to the data of four-year sampling, the territory of the Pinega Reserve (Arkhangelsk Province) is populated by more than 117 gamasid mite species belonging to 18 families. A relative richness of this fauna is obviously associated with intensive karst processes. A number of species (arctic, Siberian, mountainous) is limited to karst localities characterized by low soil temperature and a short vegetation period. When comparing the local Mesostigmata faunas from different regions, it was suggested that only species lists of unspecialized free-leaving forms should be used. Changes in the species richness of separate families and their fraction in the total suborder diversity along the latitudinal gradient from dry steppes to polar deserts are individual, reflecting different ecological potencies. The zone of deciduous forests is characterized by the richest fauna of Mesostigmata as a whole and of the majority of its families. The northern boundaries for the distribution of separate families are outlined. The number of free-leaving species in the families Ascidae, Phytoseiidae, and Zerconidae varies most smoothly along the latitudinal gradient. Even in polar deserts, Ascidae and Phytoseiidae are represented by more than a single species. It is in the taiga that the family Ascidae becomes the most diverse among Mesostigmata. In the tundra zone, this tendency is more pronounced, and in polar deserts this family constitutes 70–83% of species in local faunas, represented mainly by the genus Arctoseius.

Abstract: A new family of mesostigmatic mites, Coprozerconidae, is described on the basis of material collected from feces of the wood rat, Neotoma floridana magister Baird, in a cave in Kentucky, U.S.A. Coprozercon n. gen, is described as the type genus of the family, based on material representing the type species, Coprozercon scopaeus n. sp. The characteristics and relationships of this family among others of the cohort Epicriina are discussed, including a rationale for Coprozerconidae as the sister group of Zerconidae. The tocospermous genus Halozercon Wisniewski, Karg and Hirschmann, 1992, is transferred from the podospermous family Halolaelapidae to the tocospermous family Zerconidae.