Native Geographic Range Research Articles

Knowledge gaps in invasive species infections: Alien mammals of European Union concern as a case study

Invasive Alien Species (IAS), i.e. species introduced by humans outside their natural geographic range, may act as host or vectors of pathogens of both human and animal health relevance. Although it has been recognized that IAS should deserve more attention from a public and animal health perspective, data on the pathogens hosted by these species are not systematically collected and this prevents accurate assessments of IAS-specific risks of disease transmission.To support the future development of disease risk assessments, we systematically reviewed the scientific literature related to the pathogens of the eleven mammal species included in the European list of IAS of concern to gain insight in the amount and quality of data available. Data were analyzed to assess the current knowledge on the pathogens harbored by mammal IAS in natural conditions, through the identification of the main factors associated with research intensity on IAS pathogens and with the IAS observed pathogen species richness, the estimation of the true pathogen species richness for each IAS, and a meta-analysis of prevalence for the pathogens of health relevance.While the review confirmed that mammal IAS harbor pathogens of human and animal health relevance such as rabies virus, West Nile Virus, Borrelia burgdorferi and Mycobacterium bovis, results also highlighted strong information gaps and biases in research on IAS pathogens. In addition, the analyses showed an underestimation of the number of pathogens harbored by these species and the existence of high levels of uncertainty in the prevalence of the pathogens of health significance identified.These results highlight the need towards more efforts in making the available information on IAS pathogens accessible and systematically collected in order to provide data for future investigations and risk assessments, as well as the need of relying on alternative sources of information to assess IAS disease risk, like expert opinions.

Extensive polyploid clonality was a successful strategy for seagrass to expand into a newly submerged environment.

Polyploidy has the potential to allow organisms to outcompete their diploid progenitor(s) and occupy new environments. Shark Bay, Western Australia, is a World Heritage Area dominated by temperate seagrass meadows including Poseidon's ribbon weed, Posidonia australis. This seagrass is at the northern extent of its natural geographic range and experiences extremes in temperature and salinity. Our genomic and cytogenetic assessments of 10 meadows identified geographically restricted, diploid clones (2n = 20) in a single location, and a single widespread, high-heterozygosity, polyploid clone (2n = 40) in all other locations. The polyploid clone spanned at least 180 km, making it the largest known example of a clone in any environment on earth. Whole-genome duplication through polyploidy, combined with clonality, may have provided the mechanism for P. australis to expand into new habitats and adapt to new environments that became increasingly stressful for its diploid progenitor(s). The new polyploid clone probably formed in shallow waters after the inundation of Shark Bay less than 8500 years ago and subsequently expanded via vegetative growth into newly submerged habitats.

The Distribution, Seasonal Abundance, and Environmental Factors Contributing to the Presence of the Asian Longhorned Tick (Haemaphysalis longicornis, Acari: Ixodidae) in Central Appalachian Virginia.

Over the past decade, Haemaphysalis longicornis, the Asian longhorned tick, has undergone a geographic range expansion in the United States, from its historical range in east Asia. This tick has been characterized by its frequent parasitism of livestock, an ability to reproduce through parthenogenesis, and its ability to transmit a variety of vector-borne pathogens to livestock, wildlife, and human hosts in its native geographic range. Thus far in the United States, 17 states have reported H. longicornis populations, including 38 counties in Virginia. These numbers come from presence-absence reports provided to the U.S. Department of Agriculture, but little has been reported about this ticks' seasonality in Virginia or its habitat preferences. Our current study detected H. longicornis populations in seven of the nine surveyed counties in Virginia. Haemaphysalis longicornis were observed in multiple habitat types including mixed hardwood forests and pastures, with abundant H. longicornis populations detected at one particular pasture site in Wythe County. This study also attempted to investigate environmental conditions that may be of importance in predicting tick presence likelihood. While sample size limited the scope of these efforts, habitat type and climatic metrics were found to be important indicators of H. longicornis collection success and abundance for both the nymphal and larval life stages. This current study reports useful surveillance data for monitoring these tick populations as they become established in the western half of Virginia and provides insight into their current distribution and maintenance over a large study region.

Changing community dynamics and climate alter invasion risk of freshwater fishes historically found in invasion pathways of the Laurentian Great Lakes

AbstractAimHere, we use an integrative, comprehensive risk assessment framework as a screening tool to evaluate how the invasion risk of previously failed introduced freshwater fish species, commonly found in the live‐trade pathway, will change under future climate‐change scenarios.LocationLaurentian Great Lakes, North America.MethodsThe 34 species screened for invasion risk previously failed to establish populations, likely due to poor environmental suitability, low propagule pressure, and/or biotic resistance from the recipient community, and are most commonly found in the increasingly important live‐trade pathway. Using established trait‐based models, we quantified the probability of establishment success and probability of having high ecological impact in the decade of first introduction and present‐day communities (2020) based on known species extirpations, introductions and establishments between 1870 and 2020. We completed a climate match analysis under future climate‐change scenarios based on 16 bioclimatic variables. This approach identified a list of species that should be prioritized in surveillance management.ResultsWe identified seven species that have an increased climate match with the region and an increased probability of establishment success. Five of these species have an increased probability of high ecological impacts. Twenty‐four species have a current probability of establishment success greater than 50% and 33 species have a current probability of high ecological impacts greater than 50%. Climate match was dynamic under future climate‐change scenarios with 14 species experiencing a better match between their native geographical range and the Laurentian Great Lakes region.Main conclusionsOur models identify and predict the invasion risk of non‐native freshwater fish species present in pathways relevant to the Great Lakes region and provide a comprehensive framework for future management that prioritize efforts to species of highest risk. This framework could be applied to different taxa, pathways, and/or ecosystems to estimate current and predicted invasion risk under multiple scenarios.

Transcriptome annotation reveals minimal immunogenetic diversity among Wyoming toads, Anaxyrus baxteri.

Briefly considered extinct in the wild, the future of the Wyoming toad (Anaxyrus baxteri) continues to rely on captive breeding to supplement the wild population. Given its small natural geographic range and history of rapid population decline at least partly due to fungal disease, investigation of the diversity of key receptor families involved in the host immune response represents an important conservation need. Population decline may have reduced immunogenetic diversity sufficiently to increase the vulnerability of the species to infectious diseases. Here we use comparative transcriptomics to examine the diversity of toll-like receptors and major histocompatibility complex (MHC) sequences across three individual Wyoming toads. We find reduced diversity at MHC genes compared to bufonid species with a similar history of bottleneck events. Our data provide a foundation for future studies that seek to evaluate the genetic diversity of Wyoming toads, identify biomarkers for infectious disease outcomes, and guide breeding strategies to increase genomic variability and wild release successes.

Pathogen Spillover to an Invasive Tick Species: First Detection of Bourbon Virus in Haemaphysalis longicornis in the United States.

Haemaphysalis longicornis (Neumann, 1901) (Acari: Ixodidae), the Asian longhorned tick, is an invasive tick species present in the USA since at least 2017 and has been detected in one-third of Virginia counties. While this species is associated with the transmission of multiple pathogens in its native geographical range of eastern Asia, little is known about its ability to acquire and transmit pathogens in the USA, specifically those that are transmissible to humans, although from an animal health perspective, it has already been shown to vector Theileria orientalis Ikeda strains. Emerging tick-borne viruses such as Bourbon virus (genus: Thogotovirus) are of concern, as these newly discovered pathogenic agents have caused fatal clinical cases, and little is known about their distribution or enzootic maintenance. This study examined H. longicornis collected within Virginia (from ten counties) for Bourbon and Heartland viruses using PCR methods. All ticks tested negative for Heartland virus via qRT-PCR (S segment target). Bourbon-virus-positive samples were confirmed on two different gene targets and with Sanger sequencing of the PB2 (segment 1) gene. Bourbon virus RNA was detected in one nymphal stage H. longicornis from Patrick County, one nymph from Staunton City, and one larval pool and one adult female tick from Wythe County, Virginia. An additional 100 Amblyomma americanum (Linnaeus 1758; lone star tick) collected at the same Patrick County site revealed one positive nymphal pool, suggesting that Bourbon virus may have spilled over from the native vector, potentially by co-feeding on a shared Bourbon-virus-infected vertebrate host. Blood tested from local harvested deer revealed a 11.1% antibody seroprevalence against Bourbon virus, exposure which further corroborates that this tick-borne virus is circulating in the southwest Virginia region. Through these results, it can be concluded that H. longicornis can carry Bourbon virus and that pathogen spillover may occur from native to invasive tick species.

Reduction of Genetic Variation When Far From the Niche Centroid: Prediction for Mangrove Species

The niche-centroid hypothesis states that populations that are distributed near the centroid of the species' ecological niche will have higher fitness-related attributes, such as population abundance and genetic diversity than populations near the edges of the niche. Empirical evidence based on abundance and, more recently, genetic diversity data support this hypothesis. However, there are few studies that test this hypothesis in coastal species, such as mangroves. Here, we focused on the black mangrove Avicennia germinans. We combined ecological, heterozygosity, and allelic richness information from 1,419 individuals distributed in 40 populations with three main goals: (1) test the relationship between distance to the niche centroid and genetic diversity, (2) determine the set of environmental variables that best explain heterozygosity and allelic richness, and (3) predict the spatial variation in genetic diversity throughout most of the species' natural geographic range. We found a strong correlation between the distance to the niche centroid and both observed heterozygosity (Ho; ρ2 = 0.67 P < 0.05) and expected heterozygosity (He; ρ2 = 0.65, P < 0.05). The niche variables that best explained geographic variation in genetic diversity were soil type and precipitation seasonality. This suggests that these environmental variables influence mangrove growth and establishment, indirectly impacting standing genetic variation. We also predicted the spatial heterozygosity of A. germinans across its natural geographic range in the Americas using regression model coefficients. They showed significant power in predicting the observed data (R2 = 0.65 for Ho; R2 = 0.60 for He), even when we considered independent data sets (R2= 0.28 for Ho; R2 = 0.25 for He). Using this approach, several genetic diversity estimates can be implemented and may take advantage of population genomics to improve genetic diversity predictions. We conclude that the level of genetic diversity in A. germinans is in agreement with expectations of the niche-centroid hypothesis, namely that the highest heterozygosity and allelic richness (the basic genetic units for adaptation) are higher at locations of high environmental suitability. This shows that this approach is a potentially powerful tool in the conservation and management of this species, including for modelling changes in the face of climate change.

First report of the zoonotic nematode Baylisascaris procyonis in non-native raccoons (Procyon lotor) from Italy

Baylisascaris procyonis is a nematode parasite of the raccoon (Procyon lotor), and it can be responsible for a severe form of larva migrans in humans. This parasite has been reported from many countries all over the world, after translocation of its natural host outside its native geographic range, North America. In the period between January and August 2021, 21 raccoons were cage-trapped and euthanized in Tuscany (Central Italy), in the context of a plan aimed at eradicating a reproductive population of this non-native species. All the animals were submitted for necroscopic examination. Adult ascariids were found in the small intestine of seven raccoons (prevalence 33.3%). Parasites have been identified as B. procyonis based on both morphometric and molecular approaches. The aim of the present article is to report the first finding of this zoonotic parasite from Italy, highlighting the sanitary risks linked to the introduction of alien vertebrate species in new areas.Graphical

Gardening the menace!

Biodiversity across the globe are facing major threats to their ecological balance as a result of invasion by non-native species. In an endeavour to beautify our gardens with exotic species, several alien plants have been imported to the areas beyond their natural geographical range. Many of them are highly invasive and have deleterious impact on the environment. In an attempt to reach out to many threatened pollinators, city gardens have facilitated the implantation of several flowering non-native weeds. These non-indigenous plants often outcompete the native ones, leading to extinction of many native species. Further, these invasive species not only reduce native biodiversity but also alter key ecological processes like nutrient cycling, primary productivity, hydrology, soil structure etc. Thus, such exotic species frequently destroy natural ecosystem and have become a menace for management in the parks and reserves. In this review, we have discussed a great breadth of the causes, consequences and way forward to reduce the impact of these plant invasions on our ecosystem.

Notes on the distribution range of Sedum rubens L. (Crassulaceae) in continental Portugal

The natural geographical distribution range of Sedum rubens in continental Portugal is reassessed. Based on the Flora iberica provinces recognised for the country, the occurrence of the species in Ribatejo is confirmed but it is thus far excluded from Beira Alta.

Kalanchoe benbothae (K. subg. Fernandesiae; Crassulaceae subfam. Kalanchooideae), a new southern African species endemic to KwaZulu-Natal in the Maputaland-Pondoland Region of Endemism

Since 2016 the number of species of Kalanchoe (Crassulaceae subfam. Kalanchooideae) known from southern Africa has increased by more than 50%, from 13 to 20. We here describe the 21st species known from the subcontinent. As far as could be determined, this new species, K. benbothae, is endemic to northeastern KwaZulu-Natal, the eastern-most province of South Africa, with the entire natural geographical distribution range of the species falling within the Maputaland-Pondoland Region of Endemism. Kalanchoe benbothae fits in K. subg. Fernandesiae, a cluster of species with large, paddle- to soup plate-sized leaves, and dense, elongated, often club-shaped inflorescences. The closest relative of K. benbothae is K. luciae, which was described just over 110 years ago, and was the second representative of K. subg. Fernandesiae to have been described. Kalanchoe benbothae differs from K. luciae mostly in its reproductive morphology (corolla lobe colour and orientation, anther colour and presentation, filament length, pistil shape, and size and shape of the nectar scales).

Tree assisted migration in a browsed landscape: Can we predict susceptibility to herbivores?

To promote the sustainability of forest ecosystems and maintain ecosystem services to human populations in the context of climate change, forest managers are considering several adaptation tools. One of those, assisted migration, consists of displacing tree species and/or populations to locations with suitable future climate conditions. Assisted migration plantations, however, could fail to produce viable forests under high herbivory pressure from mammalian herbivores. Thus, selecting species and genotypes with low susceptibility to herbivores could be a key condition for the recruitment of translocated seedlings. We developed an approach to predict susceptibility to mammalian herbivores, based on the seedlings’ chemical content (a proxy of phytochemical defence and susceptibility to herbivores). We used the approach on eight North American tree species of three climate analogues regions each (i.e. locations where the current climate is similar to the future climate at plantation site). We built chemical profiles and ranked species and climate analogue based on their potential susceptibility. To assess the reliability of our approach, we compared the chemical profiles to a systematic review of these species’ chemistry and of mammalian browsing throughout their native geographic range. For most species, our chemical profiles and browse susceptibility rankings were congruent with information available in the literature, both for phytochemical defence and for browsing. Two of the eight species (Pinus strobus and Thuja occidentalis) were more susceptible than predicted based on their chemical profile. These discrepancies could be linked to specific mammalian herbivores, that were unaffected by the phytochemical defence of these species. We observed a generally higher susceptibility of broadleaf species, which could be taken into account when devising adaptive silvicultural strategies. Furthermore, we propose the chemical profiling approach as a preliminary screening tool to identify species more resistant to mammalian herbivores, but also potentially to other herbivores and pathogens. Our chemical profile approach, based on the objective assessment of multivariate analyses results, could be replicated to compare the potential susceptibility of other species. This approach could be especially useful when contending with novel plant-herbivore relationships, such as forestry and conservation assisted migration or species invasion.

Three new species of Smithiomyces from tropical Asia support an amphi-Pacific disjunct distribution in the genus

ABSTRACT Smithiomyces is reported for the first time from tropical regions in China, thus expanding its known native geographic range from the Neotropics to tropical Asia. Phylogenetic evidence from four nuclear loci supports the monophyly of Smithiomyces and a close evolutionary relationship with the nonmonophyletic genera Melanophyllum and Cystolepiota in the Agaricaceae. Detailed morphological descriptions are provided for three newly described species from China: S. asiaticus, S. heterosporus, and S. lepiotoides. Illustrations of fresh basidiomata in the field, line drawings of key anatomical features, microscopic images of anatomical features, scanning electron microscope (SEM) images of basidiospores, and a key to known species of Smithiomyces are also provided.

Origin and Evolution of the Cannabinoid Oxidocyclase Gene Family.

Cannabis is an ancient crop representing a rapidly increasing legal market, especially for medicinal purposes. Medicinal and psychoactive effects of Cannabis rely on specific terpenophenolic ligands named cannabinoids. Recent whole-genome sequencing efforts have uncovered variation in multiple genes encoding the final steps in cannabinoid biosynthesis. However, the origin, evolution, and phylogenetic relationships of these cannabinoid oxidocyclase genes remain unclear. To elucidate these aspects, we performed comparative genomic analyses of Cannabis, related genera within the Cannabaceae family, and selected outgroup species. Results show that cannabinoid oxidocyclase genes originated in the Cannabis lineage from within a larger gene expansion in the Cannabaceae family. Localization and divergence of oxidocyclase genes in the Cannabis genome revealed two main syntenic blocks, each comprising tandemly repeated cannabinoid oxidocyclase genes. By comparing these blocks with those in genomes from closely related species, we propose an evolutionary model for the origin, neofunctionalization, duplication, and diversification of cannabinoid oxidocycloase genes. Based on phylogenetic analyses, we propose a comprehensive classification of three main clades and seven subclades that are intended to aid unequivocal referencing and identification of cannabinoid oxidocyclase genes. Our data suggest that cannabinoid phenotype is primarily determined by the presence/absence of single-copy genes. Although wild populations of Cannabis are still unknown, increased sampling of landraces and wild/feral populations across its native geographic range is likely to uncover additional cannabinoid oxidocyclase sequence variants.

Expanding the known geographical distribution range of Kalanchoe waterbergensis (Crassulaceae subfam. Kalanchooideae) in northern South Africa

The natural geographical distribution range of Kalanchoe waterbergensis van Jaarsv. (Crassulaceae subfam. Kalanchooideae), previously documented only from the type locality, is extended by about 80km in a northeasterly direction in the Waterberg in northern South Africa.

The identity of Kalanchoe lubangensis R.Fern. (Crassulaceae subfam. Kalanchooideae), a little-known species endemic to southwestern Angola, with an extension of its distribution range

The identity of the little-known Kalanchoe lubangensis R.Fern. (Crassulaceae subfam. Kalanchooideae) is clarified. An amplified description is provided for this endemic species from southwestern Angola, aspects of its ecology are discussed, and it is illustrated. Kalanchoe lubangensis is compared to K. brachyloba Welw., a likely close relative. The natural geographical distribution range of K. lubangensis is extended to the Namibe province of Angola; previously it was only known from the Huíla province of that country.

Evidence of range contraction and increased metapopulation patchiness of the rare eastern Nearctic Karst Snowfly Allocapnia cunninghami Ross & Ricker, 1971

The distribution of the rare Karst Snowfly, Allocapnia cunninghami Ross & Ricker, 1971, was assessed during winters of 2019 and 2020. This species has been assigned a NatureServe ranking of G1 (= Critically Imperiled) and was recently included in a Center for Biological Diversity petition to the U.S. Fish and Wildlife Service as potentially threatened or endangered. Sampling for adult A. cunninghami occurred in 45 unique localities in central Kentucky and middle Tennessee, USA, mainly within the known historical range of this species. This species was found in winters of 2019 and 2020 in very low numbers compared to regional Allocapnia and the winter-emergent fauna in general. Allocapnia cunninghami was collected at only five unique localities and comprised only 1.1% and 1.0% of all Allocapnia and the total winter-emergent fauna individuals collected, respectively. By comparison, the widespread species A. rickeri Frison, 1942 was collected from 41 of 45 unique localities and comprised 70% of all individual adults collected. Despite the difficulties of interpreting historical locality data from 1964 to 1966, A. cunninghami appears to now be present in fewer stream sites and distributed more patchily compared to ca. 55 years ago. A confounding biological factor for A. cunninghami is that Allocapnia adults in general have poor dispersal capacity, making natural colonization and potential recolonization events substantially more problematic for what appears to be a rare species in slow decline within an already small native geographic range. By including positive collection data from 1999–2012, increasing the number of known contemporaneous sites to nine, predictive distributional models can now be generated to allow for more focused searching for previously undetected populations and potentially expand the known geographic range of this rare species.

Notes on the Natural Geographical Distribution Range of the Madagascan Kalanchoe dinklagei Rauh (Crassulaceae Subfam. Kalanchooideae)

The genus Kalanchoe Adans. (Crassulaceae subfam. Kalanchooideae) is most diverse in Madagascar where about one third of the known ca. 150 species are known to be endemic and all three of the subgenera currently recognised in the genus are represented. We discuss and provide additional information on the natural geographical distribution range of K. dinklagei Rauh, a little-known arborescent species from southern Madagascar.

First production of Italian white truffle (Tuber magnatum Pico) ascocarps in an orchard outside its natural range distribution in France.

Truffles are ectomycorrhizal species forming edible ascocarps. The Italian white truffle (Tuber magnatumPico) is the most famous and expensive species harvested to date; it comes exclusively from natural habitats in European countries. The annual production of T. magnatum is generally insufficient to respond to the high demands making its cultivation a research hotspot. The first attempt to cultivate T. magnatum started in the 1970s without success; only recently have mycorrhized plants been successfully produced. The aims of this study were (1) to assess the persistence of T. magnatum in the soil of plantations realized with mycorrhized plants and (2) to characterize the first T. magnatum orchard that produced ascocarps outside the known natural geographic range of this species. In 2018, five orchards were sampled in France, and T. magnatum was investigated in the soil. We confirmed that T. magnatum survived in the soil 3 to 8 years after planting. The key finding of this study was the harvest of T. magnatum ascocarps in 2019 and 2020 from one orchard. The production of ascocarps started 4.5 years after planting, and the ascocarps were harvested under different treesand during two consecutive seasons. A detailed analysis of the productive orchards (i.e., soil features, soil water availability, cultivation techniques) is presented. These results demonstrate the feasibility of T. magnatum cultivation worldwide by planting mycorrhized plants. The cultivation of T. magnatum could therefore become a real opportunity for farmers and could respond to the high demand of this high-priced food.

Isolation, Identification, and Bioinformatic Analysis of Antibacterial Proteins and Peptides from Immunized Hemolymph of Red Palm Weevil Rhynchophorus ferrugineus

Red palm weevil (Rhynchophorus ferrugineus Olivier, 1791, Coleoptera: Curculionidae) is a destructive pest of palms, rapidly extending its native geographical range and causing large economic losses worldwide. The present work describes isolation, identification, and bioinformatic analysis of antibacterial proteins and peptides from the immunized hemolymph of this beetle. In total, 17 different bactericidal or bacteriostatic compounds were isolated via a series of high-pressure liquid chromatography steps, and their partial amino acid sequences were determined by N-terminal sequencing or by mass spectrometry. The bioinformatic analysis of the results facilitated identification and description of corresponding nucleotide coding sequences for each peptide and protein, based on the recently published R. ferrugineus transcriptome database. The identified compounds are represented by several well-known bactericidal factors: two peptides similar to defensins, one cecropin-A1-like peptide, and one attacin-B-like protein. Interestingly, we have also identified some unexpected compounds comprising five isoforms of pheromone-binding proteins as well as seven isoforms of odorant-binding proteins. The particular role of these factors in insect response to bacterial infection needs further investigation.