Desoria calderonis sp. nov., a new species of alpine cryophilic springtail (Collembola: Isotomidae) from the Apennines (Italy), with phylogenetic and ecological considerations

We describe and delimit with integrative taxonomy the new springtail species Desoria calderonis sp. nov. (Collembola: Isotomidae). This cryophilic species is strictly linked to the supraglacial stony debris of the isolated Calderone glacier (Central Apennines, Italy), one of the southernmost glaciers of Europe. Desoria calderonis sp. nov. could belong to the nivalis-complex, a group of European mountain species included in the violacea-group. Genetic analysis (COI mtDNA barcoding) confirms the morphological attribution to the genus Desoria Nicolet in Desor, 1841, but highlights that the genus, in its current definition, is polyphyletic. We specify the peculiar micro-habitat preferences and highlight the threat of extinction for this cryophilic species in the context of the ongoing climate change and subsequent risk of complete disappearance of the glacier.

Springtail coloration at a finer scale: mechanisms behind vibrant collembolan metallic colours

The mechanisms and evolution of metallic structural colours are of both fundamental and applied interest, yet most work in arthropods has focused on derived butterflies and beetles with distinct hues. In particular, basal hexapods—groups with many scaled, metallic representatives—are currently poorly studied and controversial, with some recent studies suggesting either that thin-film (lamina thickness) or diffraction grating (longitudinal ridges, cross-ribs) elements produce these colours in early Lepidoptera and one springtail (Collembola) species. Especially the collembolan basal scale design, consisting of a single lamina and longitudinal ridges with smooth valleys lacking cross-ribs, makes them an interesting group to explore the mechanisms of metallic coloration. Using microspectroscopy, Raman spectroscopy, electron microscopy and finite-difference time-domain optical modelling, we investigated scale colour in seven springtail species that show clear metallic coloration. Reflectance spectra are largely uniform and exhibit a broadband metallic/golden coloration with peaks in the violet/blue region. Our simulations confirm the role of the longitudinal ridges, working in conjunction with thin-film effects to produce a broadband metallic coloration. Broadband coloration occurs through spatial colour mixing, which probably results from nanoscale variation in scale thickness and ridge height and distance. These results provide crucial insights into the colour production mechanisms in a basal scale design and highlight the need for further investigation of scaled, basal arthropods.

Evidence for strong environmental control on bacterial microbiomes of Antarctic springtails

Collembola are a key component of the soil biota globally, playing an important role in community and ecosystem dynamics. Equally significant are their associated microbiomes, that can contribute to key metabolic functions. In the present study, we investigated the bacterial community composition of four Antarctic springtail species to assess if and how the extreme Antarctic environment has shaped the collembolans’ microbiomes. Springtails were collected from two biogeographical regions, the maritime and the continental Antarctic. From each region, two endemic species, belonging to the genera Cryptopygus (Isotomidae, Entomobryomorpha) and Friesea (Neanuridae, Poduromorpha), were included. This experimental design allowed us to quantify the relative importance of ecological factors (different regions of occurrence) and/or phylogenetic divergence in the host (different Orders) in shaping the Collembola microbiome. The diversity and richness of springtail microbiomes was lower in the Antarctic taxa compared to published information from species from temperate regions. The microbiome composition was predominantly species-specific, with a limited core microbiome shared across the four species examined. While both geographic origin and host species influenced the associated microbiomes, the former was the prevalent driver, with closer similarity between springtails from the same bioregion than between those belonging to the same genus.

Molecular Comparison among Three Antarctic Endemic Springtail Species and Description of the Mitochondrial Genome of Friesea gretae (Hexapoda, Collembola)

Springtails and mites are the dominant groups of terrestrial arthropods in Antarctic terrestrial ecosystems. Their Antarctic diversity includes a limited number of species, which are frequently endemic to specific regions within the continent. Advances in molecular techniques, combined with the re-evaluation of morphological characters and the availability of new samples, have recently led to the identification of a number of new springtail species within previously named, but ill-defined, species entities described in the last century. One such species, the neanurid Friesea grisea, originally described from sub-Antarctic South Georgia, was for many years considered to be the only known springtail with a pan-Antarctic distribution. With the recent availability of new morphological and molecular data, it has now been firmly established that the different representatives previously referred to this taxon from the Antarctic Peninsula and Victoria Land (continental Antarctica) should no longer be considered as representing one and the same species, and three clearly distinct taxa have been recognized: F. antarctica, F. gretae and F. propria. In this study, the relationships among these three species are further explored through the sequencing of the complete mtDNA for F. gretae and the use of complete mitogenomic as well as cytochrome c oxidase I data. The data obtained provide further support that distinct species were originally hidden within the same taxon and that, despite the difficulties in obtaining reliable diagnostic morphological characters, F. gretae is genetically differentiated from F. propria (known to be present in different locations in Northern Victoria Land), as well as from F. antarctica (distributed in the Antarctic Peninsula).

Checklist and distribution of Collembola from Greater Puerto Rico

Springtails (Arthropoda, Hexapoda, Collembola) are small arthropods commonly found in soil, litter and other habitats all around the Globe. More than 9,000 species have been described worldwide, but knowledge about their diversity and distribution remains far from complete. Reports of springtail diversity in the Antilles are uneven, some islands are relatively well known, whereas others have not been explored at all. The fauna of Puerto Rico is reasonably well known, but many recent reports are scattered in published literature and unpublished theses. Here, we present a summary of all springtail species identified from the Bank of Puerto Rico, including unpublished records. As a result, we list 146 species including 43 unnamed, included in 65 genera and 17 families. Most species, 33, belong to Entomobryidae, but this possibly reflects the taxonomic expertise of specialists working in Puerto Rico rather than a real bias in the distribution of higher taxa in the islands. In addition to the new records, the database provides information on the world and local distribution of species listed. The dataset, presented here, is work in progress and will be updated as ongoing taxonomic inventories are completed.

A new species of Arrhopalites Börner, 1906 (Collembola, Symphypleona, Arrhopalitidae) from Iran with an updated key to A. diversus group of species

A new springtail species of the family Arrhopalitidae, Arrhopalites persicus sp. nov., is described from Kermanshah Province in Iran. It belongs to the diversus group of species with 3, 2, 1, 1 anterior setae on dens. It is separated from all members of this group by presence of 5+5 circumanal spines on the sixth abdominal segment and it shows reduced tibiotarsal chaetotaxy. It is the second species of the genus recorded in the country. A key to Arrhopalites diversus group of species is updated.

Contrasting Effects of Tillage and Landscape Structure on Spiders and Springtails in Vineyards

Interactions between predatory species and their potential prey are little studied in vineyards, especially considering the surrounding landscape structure. We examined the effects of soil tillage intensities in vineyard inter-rows on the activity density and diversity of spiders (Araneae) and springtails (Collembola), their potential preys, and assessed whether these effects are altered by non-crop elements in the surrounding landscape. We collected data in 16 vineyards in Austria; eight were periodically mechanically disturbed (PMD), eight had permanent green cover (PGC). The study vineyards were embedded in landscapes ranging from structurally simple to complex. Both, spiders and springtails were collected with pitfall traps. Data analyses using generalized linear mixed models (GLMM) showed different effects of soil tillage intensities on spiders and springtails and an interaction with semi-natural elements (SNEs) in the surrounding landscape. Activities of springtails were higher under PMD than under PGC while spider activity density remained unaffected. Spider family Shannon diversity was lower under PMD than under PGC, while springtail species Shannon diversity was unaffected by tillage. Under PMD, spider activity and family diversity decreased with increasing SNEs in the surroundings indicating spider emigration away from vineyards. Under PGC, spider activity density increased with increasing SNE proportions in the surroundings when springtail activity density was high. Our findings suggest that recommendations on sustainable vineyard management should include both site and landscape factors.