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

Abstract

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).

Re-Evaluating the Internal Phylogenetic Relationships of Collembola by Means of Mitogenome Data

“…Nevertheless, although their status as new gene orders is clearly plausible, caution is required because similar congeneric species (e.g., related to Seira) display the classical Pancrustacea gene order. Furthermore, although the first of these does not have other congeneric species that can be compared in terms of gene order, both Seira models are unique in the context of all other Seira species analyzed (19), that display the Pancrustacea model.…”

“…Moreover, the conservation of genes in the mitogenome minimizes the possibility that paralogous genes are sampled, and the order of genes along the molecule (gene order) provides an independent set of characters that can complement sequence analysis [16][17][18]. Different sets of complete mitogenomic data have been applied in the study of internal relationships among Collembola [19]. Leo and colleagues [2] proposed Neelipleona as the earliest diverging lineage in Collembola, although not all analyses converged to the same result, while Poduromorpha was recovered as the sister taxon to the more derived Entomobryomorpha + Symphypleona ( Figure 1F).…”

Biogeography and Genetic Diversity of Terrestrial Mites in the Ross Sea Region, Antarctica

“…Within these bioregions there are also many smaller-scale landscape barriers to dispersal, further structuring the distribution of species or genetic lineages (Collins et al, 2019;Fanciulli et al, 2001). Studies using DNA-based methods for discriminating species, including cryptic species, have now been carried out for several Antarctic terrestrial invertebrate groups including rotifers (Iakovenko et al, 2015), tardigrades (Kagoshima et al, 2013;Short et al, 2022), mites (Demetras et al, 2010;van Vuuren et al 2018) and Collembola (Bennett et al, 2016;Carapelli et al, 2020a;Carapelli et al, 2020b;. However, many of these studies are limited to small spatial scales, covering single bioregions (Liu et al, 2022).…”

“…Until recently, this was one of the only micro-arthropod species thought to occur in both the latter regions as well as the sub-Antarctic. However, driven by the application of molecular phylogenetic analyses and also supported by detailed micromorphological assessments, this species has now been redescribed as at least five species (Carapelli et al, 2020a;Carapelli et al, 2020b;Greenslade, 2018;Stevens et al, 2021).…”

Eukarya biodiversity in the Thala Hills, East Antarctica

“…The described microarthropod diversity of the Thala Hills oasis is very low, and samples examined in the current study did not include specimens of the one springtail (Collembola) recorded, previously known as Friesea grisea (Wise 1971). The taxonomy of Antarctic members of this genus has recently been extensively revised (Greenslade 2018a, Carapelli et al 2020a, 2020b, and material from Thala Hills has been re-described as the new and oasis-endemic species F. eureka (Greenslade 2018b). The prostigmatid mite Stereotydeus meyeri was sometimes commonly associated with moss vegetation and lichens (Strandtmann 1967).…”