New species and records of mites of the family Stigmaeidae (Acari: Prostigmata) collected from mosses in Southern Chile

Five new species of the family Stigmaeidae (Acari: Prostigmata), Stigmaeus palustris n. sp., Stigmaeus flexisetus n. sp., Stigmaeus patagoniensis n. sp., Pseudostigmaeus magellani n. sp. and Eryngiopus techuelche n. sp. are described from mosses in Southern Chile (Patagonia). Eustigmaeus ovatus (Chaudhri, 1965) is recorded from Chile for the first time and redescribed; Eustigmaeus chilensis (Chaudhri, 1965) is recorded from Tierra del Fuego for the first time and also redescribed.


INTRODUCTION
The predatory mite family Stigmaeidae (Acari: Prostigmata) is the largest in the superfamily Raphignathoidea and includes more than 500 species in 32 valid genera (Zhang et al. 2011;Dogan et al. 2015). Members of the family have been collected in a large range of habitats. Many stigmaeid mites from the genera Mediolata Canestrini, 1889, Agistemus Summers, 1960, Eryngiopus Summers, 1964 and some others are free-living predators of other microarthropods on plant leaves (Fan and Zhang 2005); Most species of the largest genus Stigmaeus Koch, 1836 inhabit soil, forest litter, lichens and mosses (Dogan et al. 2015a). Many species of the genera Eustigmaeus Berlese, 1910 and Ledermuelleriopsis Willmann, 1953 inhabit mosses and some feed on moses (Gerson 1972). The adult females of some Eustigmaeus and Stigmaeus species have been found attached to and apparently feeding on adult phlebotomine sandflies (Diptera: Psychodidae) in several regions of the world (Swift 1987;Zhang and Gerson 1995). Some species of Eryngiopus considered predators of crawlers of some Hemiptera (Dogan et al. 2015b).
During a study of stigmaeid mites inhabiting mosses in Patagonia (Southern Chile) five new species were revealed: Stigmaeus palustris n. sp., Stigmaeus flexisetus n. sp., Stigmaeus patagoniensis n. sp., Pseudostigmaeus magellanicus n. sp. and Eryngiopus techuelche n. sp. These new species are de-scribed in this paper. Eustigmaeus ovatus (Chaudhri, 1965) is recorded from Chile for the first time and redescribed; Eustigmaeus chilensis (Chaudhri, 1965) is recorded from Tierra del Fuego for the first time and also redescribed.

MATERIALS AND METHODS
Mites were collected from mosses using Berlese funnels and mounted in Hoyer's medium. All samples were taken in southern part of Chilean Patagonia in vicinities of Punta Arenas and Tierra del Fuego Archipelago. Mosses were collected mainly on swamps surrounded by Nothofagus forests. In the description below, the palpal, idiosomal and the leg setations follow those of Grandjean (1939Grandjean ( , 1944Grandjean ( , 1946. Prodorsal nomenclature follows that of Kethley (1990). All measurements are given in micrometers (µm) for the holotype and available paratypes (in parenthesis). In descriptions of leg setation the number of solenidia is given in parentheses. The type material is deposited in the mite collection of the Tyumen State University Museum of Zoology, Tyumen, Russia. The type material is not shared with museums in country of its origin (Chile) because of limited number of type specimens and lack of specialist on raphignathoid mites. Photographs were taken with a digital camera AxioCam ICc5 via the compound microscope Carl Zeiss AxioImager.A2 with phase-contrast and DIC illumination. Ledermuelleria ovata Chaudhri, 1965, p. 480, figs. 18-20, 32.
Male and immatures unknown.
Distribution -This species is known from U.S.A. (California) (Chaudhri 1965). It is a first record for the fauna of South America.
original description of Eustigmaeus ovatus, except for long seta k of genu I, which is more than half length of seta d of genu I. In original description of E. ovatus seta k of genu I short, needle-like and about 1/4 length of seta d of genu I (Chaudhri 1965). I consider the specimens from Chile and U.S.A. are conspecific with difference in length of seta k of genu I resulting from geographical variability.
Male and immatures unknown.
Distribution -This species was described from Chile (Jardin Botanico Nacional, Vina del Mar) (Chaudhri 1965). It was also recorded from Latvia and Lithuania (Kuznetsov and Petrov 1984) and Turkey (Dogan 2007). However records of E. chilensis from Latvia, Lithuania and Turkey would need confirmation. This species is first time recorded in the fauna of Tierra del Fuego.
Male and immatures unknown.
Etymology -The name of the new species is derived from Latin word palustris meaning swamp and refers to a habitat of the new species.
Male and immatures unknown.
Etymology -The name of the new species refers to its distribution in Patagonia.
Male and immatures unknown.
Etymology -The new species is named after Ferdinand Magellan, the first European explorer who sailed past southernmost tip of South America and discovered Patagonia in 1520.
Differential diagnosis -The new species differs from all known Pseudostigmaeus species by the absence of seta d of genu III and l" of palpal genu (vs. present in all known species).
Remarks -The genus Pseudostigmaeus Wood, 1967 includes four species, which were described from New Zealand (Fan and Zhang 2005). This is the first report of the genus Pseudostigmaeus from South America.