Mite secretions from three traditional mite-ripened cheese types: are ripened French cheeses flavored by the mites (Acari: Astigmata)?

The opisthonotal glands of Astigmata contain monoterpenes, aromatics, aliphatics, and other volatile compounds; some of these compounds act as pheromones and have antifungal effects. This study analyzed volatile compounds secreted by mites on three traditional mite-ripened cheeses from producers (Milbenkäse from Germany, Mimolette and Artisou from France). The mites obtained from various traditional ripened French cheeses (Mimolette, Laguiole, Salers, and Cantal vieux) from stores were also investigated. The gas chromatography (GC) profiles of all their hexane extracts, except the Cantal vieux one, showed almost no differences and were identical to that of Tyrolichus casei Oudemans except for trace components. Based on the GC results, the mites of Cantal vieux were identified as Acarus siro L. For the Artisou and Cantal vieux, not studied before, the influence of the mite secretions on their characteristics was investigated by analyzing the headspace volatiles from the cheeses. According to the results, neral secreted from T. casei is the main compound responsible for the lemon-like flavor of the mite-ripened cheeses, which is, hence, due to a component of the mite secretions rather than the fermentation of the cheese itself. Moreover, the compounds secreted by the mites are not directly added to the cheese through ripening as they were not detected in the odors of the Artisou and Cantal vieux after the mites were removed. However, the consumers of the Artisou usually eat also the cheese rind, and thus, can enjoy its lemon-like flavor fully.

Do 'cheese factory-specific' mites (Acari: Astigmata) exist in the cheese-ripening cabinet?

To determine whether the mites used in the ripening process of traditional cheeses are genetically unique to cheese factories, we investigated mites from three types of traditional cheeses, that use mites in the ripening process: 'Würchwitzer Milbenkäse' from Germany and 'Mimolette' and 'Artisou' from France. In addition, traditional ripened cheeses were purchased from cheese specialty stores in France (Mimolette) and Japan ('Laguiole' from France) as well as stores in temporary markets in France ('Salers' and 'Cantal vieux') and the mites obtained from those cheeses were analyzed in this study. Partial sequences of the 28S rRNA gene (28S) were determined and used to reconstruct a phylogenetic tree. Tyrolichus casei, the dominant cheese mite species from the ripening cabinets of three traditional cheese producers and two cheese specialty stores in France and Japan, had identical partial 28S sequences. All specimens from Cantal vieux from a store in the temporary market in France had an identical sequence with Acarus siro and Acarus immobilis in the determined region of the 28S sequences. Mite individuals from Salers from a store in the temporary markets in France shared the same haplotype as Acotyledon paradoxa. For the T. casei individuals from five different localities (19 individuals in total), the nuclear loci were obtained using MIG-seq. More than several thousand genomic regions are amplified simultaneously by multiplex PCR, and targeting regions surrounded by inter-simple sequence repeats (ISSRs) in the genome were sequenced using the MiSeq system (Illumina). SNPs extracted from this genome-wide analysis showed that no genetic structure existed in the populations from any region. Among the five samples from the three regions, which were more than 500 km apart and from completely different environments, the mites had no geographic bias, but all mite individuals were genetically nearly identical. Thus, we found no evidence to support the existence of 'cheese factory-specific' T. casei mites, at least in terms of genetic analysis.

Juvenile morphology of seven intertidal mite species (Acari, Oribatida, Ameronothroidea) from the East Asian region.

The present paper provides information on juvenile stages of seven intertidal oribatid mite species from the East Asian region. Larva and nymphs of the fortuyniid species Fortuynia churaumi, F. shibai, F. rotunda and Alismobates reticulatus are described and details about juvenile morphology of the selenoribatid species, Arotrobates granulatus, Indopacifica taiyo and I. tyida are given. Juveniles of the genus Arotrobates are reported for the first time and strong ventral femoral carinae are supposed to be diagnostic characters. Basically, the conservative morphology of immature stages could be confirmed in every studied taxon and its importance for phylogenetic considerations is emphasized.

First record of the family Ameronothridae (Acari: Oribatida) from Japan - new species, juvenile morphology, ecology and biogeographic remarks.

The Ameronothridae are recorded for the first time from Japanese coasts with the new species Ameronothrus yoichi sp. n. from Hokkaido. The report of this species represents the most southern occurrence of an Ameronothrus species in the Asian Pacific region. Ameronothrus yoichi sp. n. can be easily distinguished from its congeners by the conspicuously pusticulate body surface and the loss of dorsal companion setae d on all genua in the adult stage. Based on adult and juvenile morphology, a close relation to Ameronothrus maculatus and A. schneideri is suggested. Ameronothrus yoichi sp. n. is classified as a lichenivorous inhabitant of sediment-free rocky coastal substrates. Due to a lack of genetic sequence data of nearly all ameronothrid species a molecular genetic comparison is yet unfeasible, but a Bayesian inference tree based on the 18S rRNA gene shows a paraphyletic clustering of the ameronothrid A. yoichi sp. n. and Paraquanothrus grahami. http://www.zoobank.org/urn:lsid:zoobank.org:pub:5B772E2C-7D5E-4C86-9955-AB84A84C50DA.

Author Correction: Phylogeographic patterns of intertidal arthropods (Acari, Oribatida) from southern Japanese islands reflect paleoclimatic events.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Supplementary descriptions of Pergalumna amamiensis Aoki, 1984 (Acariformes, Galumnoidea) from Ryukyu Islands.

A species of oribatid mites, Pergalumna amamiensis was collected from Amami-Ohshima Island, Ishigaki Island, and Okinawa Island, Southwestern Japan. The specimens were studied in detail, and supplementary descriptions are provided; these include features of the rostrum, the subcapitulum and the surface pattern of pteromorphs. The main morphological traits for this species are summarized as follows; body length 519-570 µm, body width 363-410 µm, rostral tip pointed, sensillus with a long stalk covered by minute barbs, porose areas Aa bulbous, porose areas A1, A2, and A3 circular, surface of pteromorphs ornamented by fine granular structure and dense wrinkles, fine granular structure on prodorsum, subcapitulum, genital plates and anal plates, median pore on the notogaster represented as single pore.

Phylogeographic patterns of intertidal arthropods (Acari, Oribatida) from southern Japanese islands reflect paleoclimatic events.

The Japanese islands represent one of the world's biodiversity hotspots. Their geological history and present geography resulted in a high number of endemic species in nearly all major metazoan clades. We investigated the phylogeography of three different intertidal mite species from the Ryukyu islands and southern mainland by means of morphometry and molecular genetics. None of the species represents an endemic, nearly all show distributions ranging over at least the southern and central Ryukyus. Two species, Fortuynia shibai and F. churaumi sp. n. clearly represent sister species that are derived from a common Eastern ancestor. Molecular genetic results indicate that these species separated approx. 3 Ma before the opening of the Okinawa trough, whereas F. shibai most likely showed an ancestral distribution stretching from the central Ryukyus across the Tokara strait to Japanese mainland, whereas F. churaumi probably evolved somewhere south of the Tokara strait. Phylogenetic data further indicates that long periods of isolation resulted in heterogeneous genetic structure but subsequent low sea level stands during Pleistocene allowed recent expansion and gene flow between island populations. Comparing these patterns with those of other animals, these tiny wingless mites apparently show better dispersal abilities than partially volant terrestrial organism groups.