Diversity

Anoxia (Protanoxia) orientalis is a beetle of the family Melolonthidae for which Italy represents the western limit of its distribution. The ecology of this species is little known from the quantitative point of view. The ecological correlates of A. orientalis presence in the whole European range and, more specifically, at its western border in Sicily, are analyzed in this paper to develop a potential distribution map for Sicily and to define the habitat selection of this species. There was a clear non-random habitat selection by A. orientalis at both the European and the Sicilian scales and a clear difference in the factors affecting the presence of this species in the larger spatial scale compared to Sicily. At the European scale, the bioclimatic factors were more important than landscape factors, whereas the same was not true at the Sicilian scale. In Sicily, the populations were statistically influenced by a combination of predictors that make their potential optimal distribution very narrow and mostly limited to a few coastal areas, suggesting a region-specific ecological diversification. Since A. orientalis is in strong decline in Italy due to the degradation of coastal environments, it is necessary to minimize the degradation of the dune and back dune environments in Sicily to achieve better management for the populations of this beetle species. Full article

Tropical and subtropical Asia are major orchid diversity and endemism centers. However, the evolutionary dynamics of orchids in these areas remain poorly studied. Gastrochilus D. Don, a species-rich orchid genus from tropical and subtropical Asian forests, was employed to investigate the issue. We firstly used eight DNA regions to reconstruct the phylogeny and estimate the divergence times within Gastrochilus. We inferred the ancestral ranges and conducted a diversification analysis based on empirical and simulated data. Subsequently, we assessed the ancestral niche state and tested for phylogenetic signals in the evolution of niche conditions. Our results suggested that the most recent common ancestor of Gastrochilus occurred in the subtropical area of the East Asiatic region in the late Miocene (8.13 Ma). At least eight dispersal events and four vicariant events were inferred to explain the current distribution of Gastrochilus, associated with the global cooling from the Plio-Pleistocene. The genus experienced a slowly decreasing diversification rate since its origin, and no significant correlation between current niches and phylogenetic relatedness was observed. The diversification of Gastrochilus was attributed to accumulation through time, integrated with the intensification of the Asian Monsoon system during the Plio-Pleistocene, pollination, and epiphytism. Full article

Many reports have demonstrated that the removal of aquaculture purse seine is conducive to the restoration of aquatic vegetation and the improvement in water quality, but less attention has been paid to the effects on phytoplankton. This paper addressed the response of phytoplankton community structure to aquatic vegetation restoration after purse seine removal in Caizi Lakes. The results showed that the average dissolved oxygen (from 7.43 ± 0.25 mg/L to 9.12 ± 0.49 mg/L) and Secchi depth (from 28.40 ± 6.20 cm to 47.61 ± 14.62 cm) in the water column of the Caizi Lakes increased after the restoration of aquatic vegetation, while the average concentrations of total nitrogen (from 2.00 ± 0.16 mg/L to 1.34 ± 0.18 mg/L) and total phosphorus (from 0.15 ± 0.02 mg/L to 0.06 ± 0.01 mg/L) decreased. After the restoration of the aquatic vegetation, the cell density of phytoplankton declined from 21.04 ± 4.57 × 10⁶ cells/L to 12.74 ± 3.63 × 10⁶ cells/L, and the biomass fell from 18.13 ± 3.57 mg/L to 9.72 ± 2.55 mg/L. We also observed that Shannon–Wiener diversity, Margalef and Pielou indices of phytoplankton surged by 66.50%, 46.20% and 84.68%, respectively. Because this study demonstrated that aquatic vegetation could alleviate the eutrophication, it can provide guidance for the restoration and protection of the aquatic ecosystem. Full article

Groups of recent speciation are characterized by high levels of introgression and gene flow, which often confounds delimitation of species on a DNA basis. We analyzed nuclear DNA sequences (ETS spacer and the AGT1 gene) obtained from a large sample of the C. calocephala complex from the Balkan clade of Centaurea sect. Acrocentron (Compositae, Cardueae-Centaureinae) together with a wide representation of other species from the section. Our main goals were to verify the monophyly of the complex as currently defined and to examine the possible presence of introgression and gene flow. Within the complex, species are well-delimited from a morphological point of view and probably originated by allopatric speciation in the Balkan Peninsula. Our results confirm that the Balkan–Eurasian complex is a natural group, but the Centaurea calocephala complex shows a very complicated pattern and its phylogeny is not resolved. Our hypothesis suggests that altitudinal shifts in the transits from glacial to interglacial periods caused successive hybridization events, which are very evident from the DNA networks, between taxa not currently sympatric. As a result, confirmation of interspecific boundaries using molecular markers is extremely complicated. Full article

This is the first report of the early development for the endemic Krbava minnow Delminichthys krbavensis from a karstic field in Croatia, and the first report of any species of the genus Delminichthys. The description is based on basic morphometric measures and meristic counts during a 48-day observation of embryos and larvae acquired from successful spawning and rearing in an aquarium. The mean total length of larvae at the time of hatching was 3.12 mm. Mouth opening and independent feeding and intestinal function were observed after day 11 post-hatching (PH) at which time the yolk sac was completely absorbed in all individuals. Flexion of the urostyle began after day 18 PH and was completed by day 23 PH. Pectoral fins developed on day 7 PH, pelvic fins begin to develop by day 44 PH and the formation of caudal, dorsal and anal fin was complete by day 48 PH, when individuals presented the full set of soft rays. Understanding its early development is particularly valuable in assessing the environmental impacts on this endangered species and is essential for its effective monitoring and conservation. Full article

The Roseobacter clade represents one of the most abundant groups of marine bacteria and plays important biogeochemical roles in marine environments. Roseobacter genomes commonly contain a conserved gene transfer agent (GTA) gene cluster. A major capsid protein-encoding GTA (g5) has been used as a genetic marker to estimate the diversity of marine roseobacters. Here, the diversity of roseobacters in the coastal seawater of Arctic Kongsfjorden and Antarctic Maxwell Bay was investigated based on g5 gene clone library analysis. Four g5 gene clone libraries were constructed from microbial assemblages representing Arctic and Antarctic regions. The genus Phaeobacter was exclusively detected in Arctic seawater, whereas the genera Jannaschia, Litoreibacter and Pacificibacter were only observed in Antarctic seawater. More diverse genera within the Roseobacter clade were observed in Antarctic clones than in Arctic clones. The genera Sulfitobacter, Loktanella and Yoonia were dominant (higher than 10% of total clones) in both Arctic and Antarctic samples, implying their roles in polar marine environments. The results not only indicated a bipolar or even global distribution of roseobacters in marine environments but also showed their endemic distribution either in the Arctic or Antarctic. Endemic phylotypes were more frequently observed in polar regions than cosmopolitan phylotypes. In addition, endemic phylotypes were more abundant in Arctic samples (84.8% of Arctic sequences) than in Antarctic samples (54.3% of Antarctic sequences). Full article

Bletilla striata is a terrestrial orchid with high ornamental and medicinal values that is widely interplanted in bamboo forests. However, little is known about the effects of bamboo forest type and density on the growth of B. striata and its symbiotic relationship with root endophytic fungi. In this study, the growth state of B. striata, the community composition and diversity of its root endophytic fungal, and the fungal nutritional function were investigated in Phyllostachys edulis, P. iridescens and P. glauca forests with three densities. We found that the type and density of the bamboo forest had significant effects on the growth of B. striata, with the biomass, leaf width, root quantity and width being the highest in the low-density of the P. edulis forest. The community composition and abundance of root endophytic fungi in B. striata varied among different bamboo forests and densities, with P. edulis and P. iridescens forests dominated by Basidiomycota and Serendipita, while P. glauca prevailed by Ascomycota and Dactylonectria. The trophic modes of root endophytic fungi were also affected by forest types and densities. The abundance of symbiotroph fungi was the highest in P. edulis and P. iridescens forests and greatly varied with density gradient, and saprotrophic fungi comprised the highest proportion in the Ph. glauca forest. These results provide basic data for further research and the configuration between bamboo species and terrestrial orchids. Full article

One hundred new COI sequences of nesting female Kemp’s ridley turtles (Lepidochelys kempii) were obtained in the Rancho Nuevo Sanctuary (RNS). The COI sequences were analyzed and contrasted with others retrieved from BOLD and GenBank with the aim of investigating genetic variability, genetic divergence, and haplotypes of the nesting female population at RNS. Four new COI haplotypes for Kemp’s ridley were described; two are redundant with (LK-RN01) 97 and (LK-COI-01) 17 specimens belonging to the RNS and other localities, respectively. Nucleotide (0.00052) and haplotype (0.303) diversity showed low and conserved COI values The fixation index (FST) between these main redundant haplotypes showed a high degree of differentiation with ~1. Genetic divergence demonstrated clearly two different Kemp’s ridley nesting populations, one from RNS and a second outside Mexico. Phylogenetic COI analysis was useful to differentiate these redundant (LK-COI-01 and RNS LK-RN01) haplotypes and, therefore, these different Kemp’s ridley populations. In addition, phylogenetic COI analysis clearly separates Kemp’s ridley turtles from other sea turtle species, supporting its use as a barcode marker. Full article

Mountain lakes are unique and often isolated freshwater habitats that harbour a rich biotic diversity. This high conservation value may be reflected by diatoms, a group of algae that is known for its reliability as a bioindicator, but which has not been studied extensively in mountain lakes of the northern European Alps. In this study, the conservation value of these lakes was assessed by characterizing the number, share, and abundance of diatom Red List (RL) taxa and their relationship with environmental variables, diatom α and β diversity (assemblage uniqueness). For this purpose, linear regression models, generalized linear models, and generalized additive models were fitted and spatial descriptors were included when relevant. Of the 560 diatom taxa identified, 64% were on the RL and half of these were assigned a threat status. As hypothesized, a decreasing share of RL species in sediment and littoral samples at higher trophic levels was reflected by higher total phosphorous content and lower Secchi depth, respectively. Species-rich lakes contained a high number of RL taxa, contrasting our hypothesis of a logarithmic relationship. In turn, RL abundance increased with uniqueness, confirming our initial hypothesis. However, some of the most unique sites were degraded by fish stocking and contained low abundances of RL species. The results demonstrate the importance of oligotrophic mountain lakes as habitats for rare freshwater biota and their vulnerability in light of human impact through cattle herding, tourism, damming, and fish stocking. Additional conservation efforts are urgently needed for mountain lakes that are still underrepresented within legal conservation frameworks. Species richness and uniqueness reflect complementary aspects of RL status and thus should be applied jointly. Uniqueness can indicate both pristine and degraded habitats, so that including information on human impacts facilitates its interpretation. Full article

Soil microorganisms that inhabit extreme environments have unique metabolic capacities and/or physical structures that allow them to survive in oligotrophic conditions. The bioprospecting of unknown bacteria in the context of current advances in genome mining is fundamental for the discovery of natural products with novel properties or applications. In this study, the plant growth-promoting and biocontrol traits of a Pseudomonas isolated from soil associated with plants from the Atacama Desert were characterized by whole-genome sequencing and in vitro assays. A high-quality genome draft of Pseudomonas sp. isolate C3 was obtained. An automated biosynthetic gene cluster analysis using antiSMASH 6.0 revealed the presence of a cluster of genes for the biosynthesis, regulation, and transport of the metabolite 2,4-diacetylphloroglucinol, which showed a high protein sequence identity (>89%) with a validated orthologous gene cluster from another Pseudomonas. In addition, via an in vitro assay, the biocontrol activity of Pseudomonas sp. isolate C3 against Botrytis cinerea, Monilinia fructicola, Phytium sp., Alternaria sp., Geotrichum candidum, and Fusarium oxysporum was corroborated. Finally, through KofamKOALA, the presence of genes involved in different metabolic pathways of plant growth-promoting traits was identified, which was corroborated by in vitro assays. This study provides information obtained from genomic analyses and culture tools on a bacterial isolate from the Atacama Desert characterized by plant growth-promoting capacities and biocontrol activity. Full article

Improving ecological connectivity (EC) within landscapes by establishing corridors and ecological networks has been proposed to counteract the negative effects of habitat fragmentation and climate change on biodiversity. To be functional, ecological networks should be kept free of opportunistic invasive species that can disrupt EC between protected areas and cause biodiversity loss. The present study focused on perennial herbaceous species whose occurrence in the Adriatic-Ionian region has increased in the last two decades, namely common milkweed (Asclepias syriaca), Jerusalem artichoke (Helianthus tuberosus), Japanese knotweed (Reynoutria japonica), Bohemian knotweed (Reynoutria × bohemica), giant hogweed (Heracleum mantegazzianum), giant goldenrod (Solidago gigantea), Canadian goldenrod (Solidago canadensis), and Bermuda buttercup (Oxalis pes-caprae). All species have a high potential to spread in grasslands, abandoned agricultural fields, forest edges, and riparian areas and pose a significant threat to native plant communities and biodiversity. Restoring heavily infested sites is a major challenge because these perennial invaders are very persistent and tend to alter the soil environment in invaded habitats and prevent the recolonization of native plant communities. Therefore, early action should be taken to prevent the spread of these environmental weeds in ecological networks and protected areas with high conservation value. Full article

In the framework of the PNRA (Italian National Antarctic Research Program) project CARBONANT focusing on biogenic carbonates and held in January–February 2002, several Ross Sea banks were sampled to obtain samples of biogenic carbonates. In the Mawson Bank, species belonging to the isopod genus Chaetarcturus Brandt, 1990 were recorded, including a specimen that did not match any described species. In this paper we describe Chaetarcturus cervicornis sp. n., which is characterized by supraocular spines and two pairs of tubercle-like protrusions on the cephalothorax. The new species is very similar to C. bovinus (Brandt & Wägele, 1988) and C. adareanus (Hodgson, 1902), but has a clearly different spine pattern. The study of the species of the genus Chaetarcturus in the Ross Sea contributes to increase our knowledge on the diversity of the Antarcturidae in the Southern Ocean. Ross Sea banks seem to hold an interesting and not-well-known fauna, deserving attention in future research. Full article

Plant leaf nutrient concentrations and resorption are sensitive to fertilization, yet their co-responses under different nutrient-limited conditions have not been well studied. We conducted a meta-analysis from a global dataset of 43 reports, including 130 observations of studies with plant leaf nitrogen (N) or phosphorus (P) concentrations and nitrogen resorption efficiency (NRE) or phosphorus resorption efficiency (PRE), in response to fertilization under different nutrient-limited conditions divided by the thresholds of leaf N:P ratio values of 10 and 20. The results showed that N fertilization generally increased leaf N concentration and decreased NRE, with greater magnitudes under N-limited conditions. P fertilization also generally increased leaf P concentration and decreased PRE, with greater magnitudes under P-limited conditions. N fertilization decreased leaf P concentration and increased PRE only under the N-limited condition. Under the P-limited or N and P co-limited conditions, however, N fertilization increased leaf P concentration and did not change PRE. Moreover, P fertilization did not change leaf N concentration under all nutrient-limited conditions but significantly increased NRE under the N-limited or N and P co-limited conditions. These findings suggest that plants cope with fertilization-induced N limitation vs. P limitation at the leaf level with different nutrient-use strategies. Full article

β-diversity has been under continuous debate, with a current need to better understand the way in which a new wave of measures work. We assessed the results of 12 incidence-based β-diversity indices. Our results of gradual species composition overlap between paired assemblages considering progressive differences in species richness show the following: (i) four indices (β_-2, β_-3, β_-3.s, and β_r) should be used cautiously given that results with no shared species retrieve results that could be misinterpreted; (ii) all measures conceived specifically as partitioned components of species compositional dissimilarities ought to be used as such and not as independent measures per se; (iii) the non-linear response of some indices to gradual species composition overlap should be interpreted carefully, and further analysis using their results as dependent variables should be performed cautiously; and (iv) two metrics (β_sim and β_sor) behave predictably and linearly to gradual species composition overlap. We encourage ecologists using measures of β-diversity to fully understand their mathematical nature and type of results under the scenario to be used in order to avoid inappropriate and misleading inferences. Full article

The Rheotanytarsus muscicola species group is generally considered to be a taxonomically difficult group of non-biting midges (Diptera: Chironomidae). In this study, we review the R. muscicola species group based on the adult males from China using morphology and DNA barcodes. Rheotanytarsus ferringtoni Lin & Yao sp. n. is described and figured, and four species (Rheotanytarsus falcipedius Kyerematen, Andersen & Sæther, 2000; Rheotanytarsus fluminis Kawai & Sasa, 1985; Rheotanytarsus illiesi Siebert, 1979; and Rheotanytarsus photophilus Goetghebuer, 1921) new to China are redescribed, figured and discussed. An updated key to known adult males of the R. muscicola species group is presented. Our study shows concordance between morphological species concepts and DNA barcodes. Full article

We report for the first time the occurrence of at least two species of the phylum Gnathostomulida in the Southern Ocean, along the shores of the Ross Sea in Antarctica. At least one species for each of the orders of the phylum (Filospermoidea and Bursovaginoidea) was found using both morphological inspection and DNA metabarcoding of the shallow marine sediments collected with a Van Veen grab or by scuba diving in the area facing the Italian research station “Mario Zucchelli”. Full article

In Tengchong County, springs with wide physicochemical diversity provide a multitude of niches for extremophilic microorganisms. In this study, eight middle-low temperature spring sites along two continuous small streams with low water flow and slow speed in the fourth geothermal experience area of Rehai scenic spot were chosen, and geochemical characteristics and HTS of the 16S rRNA V4 region were used to analyze the prokaryotic community structure and diversity in the water and sediment of these sites. The effect of environmental factors on the microbial communities was explored via redundancy analysis (RDA). All sediment samples had higher alpha diversity values than the corresponding water samples. Twenty-five phyla were annotated; Euryarchaeota, Crenarchaeota, Aquificae, Thermotogae and Proteobacteria were the dominant phyla, accounting for 95.31% of all prokaryotes, with relative abundances above 5%. Aquificae dominated in water samples, while Euryarchaeota dominated in sediment samples. RDA indicated that temperature was the main factor influencing the microbial communities in the two streams. The study expands the current understanding of the microbiology of Tengchong hot springs and provides a basis for further mining of hot spring microbial and functional gene resources. Full article

Here, we address the question of if/to what extent human–wildlife conflict (HWC) can be reduced or mitigated by supra-regional or even global approaches, or whether case- and region-specific strategies are necessary. First, we try to shift the perspective from humans towards wildlife and regard modern era (near) extinctions of selected wildlife species as an ultimate expression of HWC. We then reflect on the legitimacy of ecosystem comparisons beyond the borders of biogeographical regions—an important prerequisite for global approaches. In the following, we present two case scenarios that exemplarily illustrate the topic from different perspectives: carnivore–livestock conflicts (classical view, human perspective) and wind turbine-induced mortality of bats (wildlife perspective, rarely regarded as a form of HWC). On this basis, we try to develop a framework that enables a global approach, while adequately considering case- and region-specificity. We think that a globally valid and generally approachable dimension can be defined, as long as there is a natural link: in the present case the established monophyly of the orders Carnivora and Chiroptera, i.e., representatives descending from common ancestors, thus sharing common ecological features. This natural relationship among all representatives of a systematic group (specification of the “wildlife” concept) is key for the development of an overarching strategy that can be adjusted to a specific case. Full article

Two new species of Dacrymyces, D. cerebriformis and D. sinostenosporus, are presented from southwestern China, based on morphological characteristics and phylogenetic analyses. Dacrymyces cerebriformis is characterized by obviously cerebriform basidiomata when mature, hyphae without clamp connections, and hyaline, thin-walled, allantoid, 0–7-septate basidiospores (18.4–23.1 × 5.5–7.7 μm). Dacrymyces sinostenosporus is characterized by discoid and applanate basidiomata when mature, hyphae without clamp connections, and hyaline, thin-walled, cylindrical to allantoid, 0–7-septate basidiospores (18.0–23.5 × 6.3–8.0 μm). Dacrymyces cerebriformis can be distinguished from D. sinostenosporus by the narrower thin- or thick-walled terminal cells in the marginal hyphae of the sterile surface (1.7–3.5 μm vs. 3.5–6.0 μm in diameter) and thinner basidiospores (Q = 3.14–3.28 vs. Q = 2.63–2.77). A phylogenetic analysis of Dacrymyces is performed by using a dataset composed of concatenated internal transcribed spacer regions (ITS) and a large subunit (nrLSU) of ribosomal DNA gene, and two new species nested in two distinct lineages with robust support. A full description and illustrations of the two new species are provided here. Full article