Arthropods in amber from the Triassic Period.

The occurrence of arthropods in amber exclusively from the Cretaceous and Cenozoic is widely regarded to be a result of the production and preservation of large amounts of tree resin beginning ca. 130 million years (Ma) ago. Abundant 230 million-year-old amber from the Late Triassic (Carnian) of northeastern Italy has previously yielded myriad microorganisms, but we report here that it also preserves arthropods some 100 Ma older than the earliest prior records in amber. The Triassic specimens are a nematoceran fly (Diptera) and two disparate species of mites, Triasacarus fedelei gen. et sp. nov., and Ampezzoa triassica gen. et sp. nov. These mites are the oldest definitive fossils of a group, the Eriophyoidea, which includes the gall mites and comprises at least 3,500 Recent species, 97% of which feed on angiosperms and represents one of the most specialized lineages of phytophagous arthropods. Antiquity of the gall mites in much their extant form was unexpected, particularly with the Triassic species already having many of their present-day features (such as only two pairs of legs); further, it establishes conifer feeding as an ancestral trait. Feeding by the fossil mites may have contributed to the formation of the amber droplets, but we find that the abundance of amber during the Carnian (ca. 230 Ma) is globally anomalous for the pre-Cretaceous and may, alternatively, be related to paleoclimate. Further recovery of arthropods in Carnian-aged amber is promising and will have profound implications for understanding the evolution of terrestrial members of the most diverse phylum of organisms.

Distribution, habitats, and redescription of the rare mite species emIphidonopsis/em emsculptus/em Gwiazdowicz, 2004 (Mesostigmata: Ascidae).

Iphidonopsis sculptus Gwiazdowicz, 2004, is currently known only from the type locality in eastern Poland and a record in southwestern Finland (Huhta, 2016). Here, we record this species from twelve localities elsewhere (Europe, Siberia, Far East of Russia, Canada) indicating its broadly Holarctic geographical range. Another genus member, Iphidonopsis magnanalis (Ma Yin, 1999), is known only from China. About half of Iphidonopsis sculptus records are associated with litter of coniferous or mixed forests, but the others, including samples with juveniles (deutonymphs), were found in bracket fungi or under tree bark. The finding of two adult females on a bark beetle, Dryocoetes affaber (Mannerheim) (Coleoptera: Curculionidae: Scolytinae), suggests a phoretic association, though members of the closely related genus Zerconopsis Hull, 1918 as well as of all of the subfamily Arctoseiinae are known only from phoretic dispersal by nematoceran dipterans. The morphology of adults and an immature instar (deutonymph) of I. sculptus is redescribed and newly described, respectively, and illustrated in detail. A subdivision of the subfamily Arctoseiinae Evans, 1963 into three tribes is proposed-Arctoseiini Evans, 1963 (including Arctoseius Thor, 1930 and Iphidozercon Berlese, 1903), Zerconopsini tribe n. (Zerconopsis Hull, 1918; Xenoseius Lindquist Evans, 1965; and Iphidonopsis Gwiazdowicz, 2004), and Maxiniini tribe n. (Maxinia Lindquist Makarova, 2012).

Review of the genera Berlesia Canestrini, 1884, and Katydiseius Fain amp; Lukoschus, 1983, the subfamily Katydiseiinae Fain amp; Lukoschus, 1983, and their family group relationships (Acari: Mesostigmata: Gamasina), with description of three new species parasitic on gryllacridid crickets (Orthoptera).

The gamasine genus Berlesia Canestrini, 1884, is revived and further diagnosed, based on descriptions of adult females, males and nymphs of three new species (B. hospitabilis sp. nov., B. multisetosa sp. nov., B. vorontsovi sp. nov.) ectoparasitic on raspy crickets of three genera of Gryllacrididae (Ensifera) from Australia and the Philippines. A tight sister relationship of Berlesia with the monobasic genus Katydiseius Fain Lukoschus, 1983, known only from a pseudophylline katydid in Malaysia, is proposed. The subfamily Katydiseiinae Fain Lukoschus, 1983 (previously included in the family Otopheidomenidae in the superfamily Phytoseioidea) is redefined to include only those two genera, and moved to the dermanyssoid family Laelapidae, while its previously other monobasic genus, Eickwortius Zhang, 1995, is retained tentatively in the family Otopheidomenidae. Among other taxa relevant to Katydiseiinae reviewed here, Berlesia cultrigera Berlese, 1910a is transferred to the genus Orthopteroseius Mo, 1996, at present Otopheidomenidae, as Orthopteroseius cultrigerum (Berlese) comb. nov., and Berlesia nuda Berlese, 1910b is transferred to the genus Prasadiseius Wainstein, 1972, at present Otopheidomenidae, as Prasadiseius nudum (Berlese) comb. nov. A key to the two genera and five species recognized as belonging in Katydiseiinae is presented. Notable morphological traits of Berlesia, including only deutonymphs equipped with well-developed claws and males with dimorphically more elongated salivary stylets, are discussed. The one known life cycle of a species of Berlesia, B. hospitabilis sp. nov., includes protonymphipary, followed by a fully functioning deutonymph, and male copulation with pharate females-traits, rarely or not known among gamasine mite associates of invertebrates. The possible significance of elongate spermatodactyls and male reduced feeding are explored.

A new species of Podapolipus (Acari: Heterostigmata: Podapolipidae) from an Australian gryllacridid cricket (Orthoptera), with keys to orthopteran-associated species of the genus.

A new species of the ectoparasitic mite genus Podapolipus Rovelli Grassi, 1888 from a recently described species of the raspy cricket genus Chauliogryllacris Rentz, in Rentz and John,1990 (Orthoptera: Gryllacrididae) is described. The main distinctions of Podapolipus gryllacridi n. sp. from its described congeners from orthopterans are the larval female and adult male having all dorsal and ventral idiosomatic setae, except the greatly elongated pair of scapular setae (and the caudal setae of the larval female), reduced to the size of microsetae; the larval female having separate tergites C and D; the male having an entire prodorsal shield, with apex of the aedeagus between bases of setae v1; and the adult female having smooth dorsal shields. Novel biological features of this parasite include its adult females' dwelling in the hollow sternal apodemes of their host, and its larval females using their host's other parasite, a gamasine mite, as phoretic and facultative hyperparasitic hosts. Keys are presented for the larval females and adult males of Podapolipus species associated with orthopterans. Problems with the generic concept of Podapolipus and closely related genera are reviewed. This is the first record of a podapolipid associated with orthopterans of the family Gryllacrididae.

Acari of Canada.

Summaries of taxonomic knowledge are provided for all acarine groups in Canada, accompanied by references to relevant publications, changes in classification at the family level since 1979, and notes on biology relevant to estimating their diversity. Nearly 3000 described species from 269 families are recorded in the country, representing a 56% increase from the 1917 species reported by Lindquist et al. (1979). An additional 42 families are known from Canada only from material identified to family- or genus-level. Of the total 311 families known in Canada, 69 are newly recorded since 1979, excluding apparent new records due solely to classification changes. This substantial progress is most evident in Oribatida and Hydrachnidia, for which many regional checklists and family-level revisions have been published. Except for recent taxonomic leaps in a few other groups, particularly of symbiotic mites (Astigmata: feather mites; Mesostigmata: Rhinonyssidae), knowledge remains limited for most other taxa, for which most species records are unpublished and may require verification. Taxonomic revisions are greatly needed for a large majority of families in Canada. Based in part on species recorded in adjacent areas of the USA and on hosts known to be present here, we conservatively estimate that nearly 10,000 species of mites occur in Canada, but the actual number could be 15,000 or more. This means that at least 70% of Canada's mite fauna is yet unrecorded. Much work also remains to match existing molecular data with species names, as less than 10% of the ~7500 Barcode Index Numbers for Canadian mites in the Barcode of Life Database are associated with named species. Understudied hosts and terrestrial and aquatic habitats require investigation across Canada to uncover new species and to clarify geographic and ecological distributions of known species.

A new tribe of tarsonemid mites (Trombidiformes: Heterostigmatina) parasitic on tetrigid grasshoppers (Orthoptera).

Podotarsonemini tribe nov. (Tarsonemidae: Acarapinae), with one nominate genus Podotarsonemus gen. nov., is proposed for seven new species of tarsonemid mites collected from the hindwings of pygmy grasshoppers of the family Tetrigidae (Orthoptera). The new tribe is placed within the tarsonemid subfamily Acarapinae on the basis of several morphological synapomorphies, as well as on parasitism of insects. In light of this new tribe, a revised description of the Acarapinae is provided, as are full tribal, generic and species descriptions for the Podotarsonemini, and a key to species. In view of Podapolipidae, the sister family of Tarsonemidae, consisting entirely of obligatory parasitic mites, the distinction between the two constituent sister families of Tarsonemoidea as well as the ancestral feeding habits of that superfamily are considered. These mites and their host grasshoppers were collected from Bolivia, Ecuador, Honduras, southern India, Japan, Papua New Guinea, South Africa and two localities in north-eastern Australia. This distribution suggests that the Podotarsonemini are an ancient lineage of Tarsonemidae that radiated on the Gondwanan Tetrigidae during the Jurassic.

Systematics and biology of mites associated with neotropical hispine beetles in unfurled leaves of Heliconia, with descriptions of two new genera of the family Melicharidae (Acari: Mesostigmata: Gamasina: Ascoidea).

Two new genera Makarovaia and Hispiniphis are described from adults and immatures of newly described species associated with hispine beetles of the genera Chelobasis and Cephaloleia, respectively, occupying unfurled leaves of Heliconia in lowland rainforest of Costa Rica. The new genera share a suite of unique morphological attributes, but are tentatively assigned to the family Melicharidae. While all instars of the mites can be found under the elytra of their adult beetle hosts, adult mites also move freely on and off the beetles. A new form of laboulbeniaceous fungus of the genus Rickia is frequently associated with adult mites of Makarovaia as well as their beetle hosts, yet evidently rarely with mites of a species of Hispiniphis or its beetle hosts which may co-occupy the same host leaves. Limited data suggest considerable host specificity between mites and their beetle hosts. Whether the association of these mites with hispine beetles may be ancient, prior to the beetles' adaptation to living in unfurled leaves of host plants, or is a more recent invasion and partitioning of the rolled leaf beetle fauna, is discussed.

A new species of the gamasid mite genus Arctoseius Thor, 1930 (Parasitiformes, Mesostigmata, Ascidae) from Russia with a key to the multidentatus species-group.

A new gamasid mite species belonging to the genus Arctoseius Thor, 1930 is described from Russia. Arctoseius koltschaki sp. n. is distributed in the plain and mountain tundras from Khibiny Mountains to Chukotka on the north and to West Sayan Mountains on the south. A diagnosis and a key for identification of species comprising the multidentatus species-group (Arctoseius multidentatus Evans, 1955; Arctoseius wisniewskii Gwiazdowicz & Kamczyc, 2009; Arctoseius sexsetus Lindquist & Makarova, 2011; Arctoseius haarlovi Lindquist & Makarova, 2011; and Arctoseius koltschaki sp. n.) are given.

Review of the mite subfamily Arctoseiinae Evans with a key to its genera and description of a new genus and species from Siberia (Parasitiformes, Mesostigmata, Ascidae).

We redefine the subfamily Arctoseiinae of the family Ascidae, and describe a new genus, Maxiniagen. n., based on a new species, Maxinia arctomontanasp. n., whose adults display a combination of attri-butes uniquely different from other genera of the subfamily. The geographical range of Maxinia arctomontana is limited by arctic and mountain landscapes of Siberia. This description provides furtherdata on the arctic distribution and morphological diversity of the subfamily Arctoseiinae, which is unusually well represented in that region (26-83% in local gamasid mite faunas). Conceptual problems with the genus Iphidonopsis Gwiazdowicz, 2004 are reviewed, and a new combination, Iphidonopsis magnanalis (Ma & Yin, 1999) comb. n., is presented for Iphidozercon magnanalis Ma & Yin, 1999 from China. The genus Diseius Lindquist & Evans, 1965 is provisionally moved from the family Ascidae to the Digamasellidae. A new key to the genera of Arctoseiinae is presented.