A new genus and species of Laelapidae Canestrini from Sri Lanka (Acari: Mesostigmata)

We describe a new monotypic genus in the mite family Laelapidae, Hyposternus gen. nov., to accommodate a new species, H. ceylonicus sp. nov., on the basis of female, male and protonymph specimens collected from soil-litter in Sri Lanka. The female of the new genus differs from other genera of Laelapidae by having a strongly desclerotised sternal shield, essentially represented by a narrow anterior and lateral sclerotised ridges. Other distinctive features of the new species include the absence of dorsal shield seta z3, an epistome projecting anteriorly, movable digit of the chelicera tapered apically, an elongate anal shield, thorn-like opisthogastric setae, an anteriorly widened hypostomal groove, and long dorsal macrosetae ad1 on femora II–IV.

A new species of Lasioseius (Acari: Blattisociidae) from Brazil with morphological and DNA barcode data

Lasioseius foliatisetus n. sp. is described based on the morphology and molecular markers of adult females collected in litter/soil samples of the Caatinga and Pantanal, extensive Brazilian biomes. This new species can be distinguished from other Lasioseius species mainly by having fixed cheliceral digit with three teeth in addition to apical tooth, most dorsal shield setae leaf-shaped, and ventrianal shield with seven pairs of setae (including Jv5) in addition to the circumanal setae. The determined nucleotide sequences of the CytB gene and of ITSS of Lasioseius foliatisetus n. sp. are the first data of these types deposited in a published database (GenBank) for a species of this genus. The phylogenetic tree generated in the analysis of ITSS sequences showed a clade constituted only by species of the superfamily Phytoseoidea, including L. foliatisetus n. sp.. The phylogenetic tree generated in the ML analysis based on CytB showed a separation of the blattisociid species (including L. foliatisetus n. sp.) in one clade and the phytoseiid species in another clade. The analysis of the 28S 1–3 domain by itself did not allow the separation of the new species here described from species of other blattisociid genera.

Metagynella pangooli sp. nov. from decaying baobab tree from Senegal with the notes on genus Metagynella Berlese, 1919 (Acari: Mesostigmata: Metagynuridae)

A new species of Metagynella, M. pangooli sp. nov. is described based on female and male specimens collected from decaying baobab trees (Adansonia digitata) in Senegal. The new species differs from congeners by the sculptural pattern of the dorsal shield and the shape of the sternal shield. A list and a new key to the known Metagynella species are also presented.

A new opilioacarid species (Parasitiformes: Opilioacarida) from Crete (Greece) with notes on its karyotype

A new species of opilioacarid mite, Opilioacarus thaleri n. sp., is described from mid-level elevation close to the seashore in Crete (Greece). It was found on moister sites, under stones or inside stone accumulations in phrygana vegetation. The peak of activity was found to be in early May. The diagnostic morphological characters include 7–8 eugenital setae (female), 5/7 setae on each sclerite at pregenital and genital areas, 11 setae on genital area (male), anterior dorsal shield with two pairs of eyes and 60–70 stout, ribbed setae, 5 (female) or 6 (male) leaf setae plus one pectinate seta on the palp tarsus, and the "simple" type of ovipositor with two pairs of glands, a pair of ducts plus a basal structure. The female karyotype comprises 16 monocentric chromosomes, predominantly with acrocentric morphology. Comparison with data of the ixodids and mesostigmatids indicates that a low number of chromosomes and predomination of acrocentric chromosomes could be plesiomorphies of the parasitiform mites.

A new genus and new species of macronyssid mite (Mesostigmata: Gamasina: Macronyssidae) from Brazilian caves including molecular data and key for genera occurring in Brazil

A new genus and a new species of macronyssid mites is described based on material collected from caves in Minas Gerais state, Southeastern Brazil, and additional occurrences from caves in Rio de Janeiro (Southeast) and Pará (Eastern Amazon region). The new genus may be distinguished from other Macronyssidae genera by the combination of sternal shield with a distinct X-shaped area; sternal shield bearing three pairs of setae and two pairs of pores; sternal gland absent; anterior spur on coxa II lacking; adults with dorsal shield entire and j and J series complete; adults and protonymphs with setae J5 minute; males with strong-pores on dorsal shield and peritrema short extending from posterior margin of coxae II to the anterior margin of coxae IV. A key for genera occurring in Brazil is provided, as well sequences from the mitochondrial large subunit of ribosome (16S).

Does diet affect morphological parameters of Neoseiulus tunus (De Leon) (Acari: Phytoseiidae)?

Neoseiulus Hughes is one of the most diverse genus of Phytoseiidae, with approximately 400 described species. Among them, Neoseiulus tunus (De Leon) is very frequent and abundant in the Neotropical region. Although considerable amount of data about morphological variation of phytoseiid mites are available, the possible causes of intraspecific variations are still poorly understood, being diet and feeding habit usually reported as the main drivers. The present study investigated the influence of three different diets on morphological traits of taxonomic interest of N. tunus, aiming to verify whether diet is a determinant factor in the morphological pattern of this species and which structures are most affected by them. Our results show that based on the diet treatment, populations of N. tunus may be differentiated based on the size of morphological traits. All treatments differ from stock population and among them, except between populations feeding with Aculops lycopersici (Massee) (Eriophyidae) and Tetranychus urticae (Kock) (Tetranychidae). The widest range occurred on the dorsal setae, macrosetae of leg IV, width of the dorsal shield, distance between the bases of the genital’s setae and posterior width of the ventrianal shield. Most of the dorsal setae responded to the treatment with significant variation, being the longest lengths observed when the A. lycopersici was offered as diet. Considering the other two diets, the variation does not present a clear increasing or reducing pattern.

The fossil record of whip spiders: the past of Amblypygi

Whip spiders (Amblypygi), as their name suggests, resemble spiders (Araneae) in some aspects, but differ from them by their heart-shaped (prosomal) dorsal shield, their prominent grasping pedipalps, and their subsequent elongate pair of feeler appendages. The oldest possible occurrences of whip spiders, represented by cuticle fragments, date back to the Devonian (c. 385 mya), but (almost) complete fossils are known from the Carboniferous (c. 300 mya) onwards. The fossils include specimens preserved on slabs or in nodules (Carboniferous, Cretaceous) as well as specimens preserved in amber (Cretaceous, Eocene, Miocene). We review here all fossil whip spider specimens, figure most of them as interpretative drawings or with high-quality photographs including 3D imaging (stereo images) to make the three-dimensional relief of the specimens visible. Furthermore, we amend the list by two new specimens (resulting in 37 in total). The fossil specimens as well as modern whip spiders were measured to analyse possible changes in morphology over time. In general, the shield appears to have become relatively broader and the pedipalps and walking appendages have become more elongate over geological time. The morphological details are discussed in an evolutionary framework and in comparison with results from earlier studies.

Morphological description, DNA barcodes and phylogenetic placement of a new mite species: Dinogamasus saengdaoae sp. nov. (Mesostigmata: Laelapidae) found in the acarinarium of carpenter bees in Thailand

Dinogamasus saengdaoae Attasopa & Ferrari sp. nov. is described based on adult females from the abdominal pouch of females of Xylocopa tenuiscapa (Westwood) in Chiang Mai Province, Northern Thailand. The new species belongs to the D. perkinsi (Oudemans) group (sensu LeVeque) and can be distinguished from its congeners by the combination of the following characters: (1) dorsal shield covering opisthosoma neither laterally nor posteriorly; (2) opisthonotal soft cuticle with a pair of relatively long setae posteriorly; (3) setae pd1, pd2 on genu I and ad3, pd3, pl1, pl2 on both genu and tibia I conical. Maximum likelihood-based analysis of newly-generated DNA barcodes shows that the sequenced specimens of D. saengdaoae sp. nov. form a monophyletic cluster, and parsimony analysis of a previously available morphological dataset indicates that the species comprises a strongly-supported clade with D. perkinsi and D. piperi LeVeque. We provide an additional couplet for Lundqvist’s key for the species of Dinogamasus Kramer to facilitate identification of D. saengdaoae sp. nov..

Two new species of the genus Bloszykiella (Acari: Uropodidae) from the Afrotropical region

Two new Bloszykiella species are discovered and described from the Afrotropical realm. Bloszykiella rammsteini sp. nov. (from Zimbabwe) differs from its congeners in the sculptural pattern of the dorsal shield, the strongly sclerotized U-shaped grooves on the dorsal shield and pilose dorsal setae. Bloszykiella lindemanni sp. nov. (from Rwanda) differs from the other species in the shape of the sternal setae, setae on the apical margin of the pygidial shield and the sculptural pattern of the female genital shield.

Morphological changes in Neoseiulus californicus (Acari: Phytoseiidae)

This paper deals with the detailed morphological observation of larva, protonymph and deutonymph, as well as female and male adults of Neoseiulus californicus (McGregor) based on laboratory reared specimens. The main changes are as follows: larva with one dorsal shield, while protonymph with two, which fused into a holodorsal shield in deutonymph; 9 pairs of dorsal setae in larvae, 14 pairs in protonymph, and 19 pairs in deutonymph and adult; the immature stages without discernible ventrianal shield, though hypoplastic shield, a weakly sclerotized small plate around the anal pore, present in the protonymph and deutonymph. larva and protonymph each with seven pairs of ventral setae, while deutonymph and adult each with 12 pairs; movable digit with one or two teeth in larva, three teeth in protonymph, deutonymph or adult. The development of morphological traits in ontogenesis of N. californicus could provide helpful basis to identify it practically from its relatives.