Search results for "fylogenia"

Redescription and phylogenetic analysis of the type species of the genus Panagrellus Thorne, 1938 (Rhabditida, Panagrolaimidae), P. pycnus Thorne, 19…

2021

Abstract The identity of Panagrellus pycnus, the type species of the genus Panagrellus, is discussed after studying specimens from a cultured population collected in Italy that fits the original material of the species. A new characterization is consequently provided as follows: body 0.93–1.32 mm long, lip region continuous with the adjoining body, stoma with gymnostom very reduced, pharynx with not swollen metacorpus, neck 161–203 µm long, excretory pore at level of the metacorpus, post-vulval uterine sac 99–162 µm long or 2.6–3.8 times as long as the body diameter divided in a short tubular proximal part and a long swollen distal part, vulva post-equatorial (V = 63–69), female tail conica…

Local environment and space drive multiple facets of stream macroinvertebrate beta diversity

2018

AIM: Understanding variation in biodiversity typically requires consideration of factors operating at different spatial scales. Recently, ecologists and biogeographers have recognized the need of analysing ecological communities in the light of multiple facets including not only species‐level information but also functional and phylogenetic approaches to improve our understanding of the relative contribution of processes shaping biodiversity. Here, our aim was to disentangle the relative importance of environmental variables measured at multiple levels (i.e., local, catchment, climate, and spatial variables) influencing variation in macroinvertebrate beta diversity facets (i.e., species, tr…

Whole-genome analysis reveals contrasting relationships among nuclear and mitochondrial genomes between three sympatric bat species

2023

Understanding mechanisms involved in speciation can be challenging, especially when hybridization or introgression blurs species boundaries. In bats resolving relationships of some closely related groups has proven difficult due subtle interspecific variation both in morphometrics and molecular datasets. The endemic South American Histiotus bats, currently considered a sub-genus of Eptesicus, harbor unresolved phylogenetic relationships and of those is a trio consisting of two closely related species: Eptesicus (Histiotus) macrotus and E. (H.) montanus, and their relationship with a third, E. (H.) magellanicus. The three sympatric species bear marked resemblance to each other, but can be di…

Exploring evolutionary responses to increasing temperature in an environmental opportunistic pathogen

2017

Integrative descriptions of two new Macrobiotus species (Tardigrada, Eutardigrada, Macrobiotidae) from Mississippi (USA) and Crete (Greece)

2021

In this paper, we describe two new Macrobiotus species from Mississippi (USA) and Crete (Greece) by means of integrative taxonomy. Detailed morphological data from light and scanning electron microscopy, as well as molecular data (sequences of four genetic markers: 18S rRNA, 28S rRNA, ITS-2 and COI), are provided in support of the descriptions of the new species. Macrobiotus annewintersaesp. nov. from Mississippi belongs to the Macrobiotus persimilis complex (Macrobiotus clade B) and exhibits a unique egg processes morphology, similar only to Macrobiotus anemone Meyer, Domingue & Hinton, 2014, but mainly differs from that species by the presence of eyes, granulation on all legs, den…

High‐resolution 3D forest structure explains ecomorphological trait variation in assemblages of saproxylic beetles

2022

1. Climate, topography and the 3D structure of forests are major drivers affecting local species communities. However, little is known about how the specific functional traits of saproxylic (wood-living) beetles, involved in the recycling of wood, might be affected by those environmental characteristics. 2. Here, we combine ecological and morphological traits available for saproxylic beetles and airborne laser scanning (ALS) data in Bayesian trait-based joint species distribution models to study how traits drive the distributions of more than 230 species in temperate forests of Europe. 3. We found that elevation (as a proxy for temperature and precipitation) and the proportion of conifers p…

Traits mediate niches and co‐occurrences of forest beetles in ways that differ among bioclimatic regions

2021

Aim The aim of this study was to investigate the role of traits in beetle community assembly and test for consistency in these effects among several bioclimatic regions. We asked (1) whether traits predicted species’ responses to environmental gradients (i.e. their niches), (2) whether these same traits could predict co-occurrence patterns and (3) how consistent were niches and the role of traits among study regions. Location Boreal forests in Norway and Finland, temperate forests in Germany. Taxon Wood-living (saproxylic) beetles. Methods We compiled capture records of 468 wood-living beetle species from the three regions, along with nine morphological and ecological species traits. Eight …

Large variation in mitochondrial DNA of sexual and parthenogenetic Dahlica triquetrella (Lepidoptera: Psychidae) shows multiple origins of parthenoge…

2013

Background Obligate parthenogenesis is relatively rare in animals. Still, in some groups it is quite common and has evolved and persisted multiple times. These groups may provide important clues to help solve the ‘paradox of sex’. Several species in the Psychidae (Lepidoptera) have obligate parthenogenesis. Dahlica triquetrella is one of those species where multiple transitions to parthenogenesis are postulated based on intensive cytological and behavioural studies. This has led to the hypothesis that multiple transitions from sexuals to diploid parthenogens occurred during and after the last glacial period, followed by transitions from parthenogenetic diploids to parthenogenetic tetraploid…

Phylogenetic diversity and affiliation of tropical African ectomycorrhizal fungi

2022

Ectomycorrhizal fungi form a mutualistic symbiosis with plant roots, and are key for nutrient cycling in many ecosystems. Here we study the ectomycorrhizal fungal communities in the Oueme Superieur reserve forest in Benin (West Africa). We use phylogenetic methods to test if the species from the study site are closer to other tropical African species than to species from other regions. The Oueme Superieur community was represented by nine Operational Taxonomic Units in Amanitaceae, one in Boletaceae, one in Cantharellaceae, one in Cortinariaceae, two in Inocybaceae, fourteen in Russulaceae and three in Sclerodermataceae. Of these thirty-one Operational Taxonomic Units, twenty had no record …

Cryo-EM structure of ssDNA bacteriophage ΦCjT23 provides insight into early virus evolution.

2022

AbstractThe origin of viruses remains an open question. While lack of detectable sequence similarity hampers the analysis of distantly related viruses, structural biology investigations of conserved capsid protein structures facilitate the study of distant evolutionary relationships. Here we characterize the lipid-containing ssDNA temperate bacteriophage ΦCjT23, which infects Flavobacterium sp. (Bacteroidetes). We report ΦCjT23-like sequences in the genome of strains belonging to several Flavobacterium species. The virion structure determined by cryogenic electron microscopy reveals similarities to members of the viral kingdom Bamfordvirae that currently consists solely of dsDNA viruses wit…