Taxonomic Uncertainty Research Articles

Vascular plant extinction in the continental United States and Canada.

Extinction rates are expected to increase during the Anthropocene. Current extinction rates of plants and many animals remain unknown. We quantified extinctions among the vascular flora of the continental United States and Canada since European settlement. We compiled data on apparently extinct species by querying plant conservation databases, searching the literature, and vetting the resulting list with botanical experts. Because taxonomic opinion varies widely, we developed an index of taxonomic uncertainty (ITU). The ITU ranges from A to F, with A indicating unanimous taxonomic recognition and F indicating taxonomic recognition by only a single author. The ITU allowed us to rigorously evaluate extinction rates. Our data suggest that 51 species and 14 infraspecific taxa, representing 33 families and 49 genera of vascular plants, have become extinct in our study area since European settlement. Seven of these taxa exist in cultivation but are extinct in the wild. Most extinctions occurred in the west, but this outcome may reflect the timing of botanical exploration relative to settlement. Sixty‐four percent of extinct plants were single‐site endemics, and many occurred outside recognized biodiversity hotspots. Given the paucity of plant surveys in many areas, particularly prior to European settlement, the actual extinction rate of vascular plants is undoubtedly much higher than indicated here.

The Form and Substance of Equitable Estoppel

Taxonomic uncertainty has long been a feature of equitable estoppel. While the unifiers had their heyday in a period roughly centred on the 1980s, the splitters are now in the ascendant. At the forefront of the movement is Ben McFarlane, who has argued that what is known as ‘equitable estoppel’ in fact consists of five separate principles. This paper questions that growing consensus. It considers the case for the unity of equitable estoppel by identifying what might be understood to be its core principle, and then considering a series of questions that can help us to understand whether that core principle can be said to underlie ‘equitable estoppel’ as a whole. A central plank in the case for the disunity of equitable estoppel is the claim that a promise is required for some categories of case but not others. While there is some strength in the argument that a promise should be required, numerous leading cases arising in different contexts make it clear that responsibility for detrimental reliance on an assumption as to one’s future conduct does not depend on the making of a promise or commitment.

Phylogeny, taxonomic reassessment and ‘ecomorph’ relationship of theOrientallactaga sibiricacomplex (Rodentia: Dipodidae: Allactaginae)

AbstractThe ecological gradient–morphological variation (‘ecomorph’) relationship has long interested ecologists and evolutionary biologists, but it is applied far less frequently than genetic differentiation in cryptic species detection and species identification. With integrative methods, we revise taxonomic uncertainties in the Orientallactaga sibirica complex (OSC), with 298 sequence specimens and 469 voucher specimens from 138 localities covering nearly the entire distribution of the OSC. Phylogenetic relationships are assessed by Bayesian inference and maximum likelihood using two mitochondrial and nine nuclear genes. We use species-delimitation approaches to divide and validate the ‘candidate species’. We evaluate correlations between ecological divergence and phylogenetic splits, and visualize geographical patterns of morphological variation. The OSC is divided into four phylogenetic groups, the Ognevi, Altay, Bogda and Sibirica groups, and the OSC exhibits a significant ecomorph relationship and ecological divergence pattern. Morphological variations not only follow the general regularity under a large gradient of ecological factors, but are also closely related to the local environment/habitat. We suggest considering the comprehensive ecomorph relationship to identify species. Molecular analyses reveal that the OSC more easily forms deeply divergent lineages in the foothills and this differentiation depth may be related to mountain system size.

Taxonomy and distribution of bottlenose dolphins (genusTursiops) in Australian waters: an osteological clarification

Species relationships in the bottlenose dolphin (genus Tursiops Gervais, 1855) are controversial. We carried out a comprehensive osteological study of 264 skulls, including type specimens, and 90 postcranial skeletons of Tursiops spp. to address taxonomic uncertainties in Australia using two-dimensional (2D) measurements, and three-dimensional geometric morphometrics (3DGM), tooth and vertebral counts, and categorical data. Analyses provided support for the presence of two forms, aligned to the Indo-Pacific bottlenose dolphin (Tursiops aduncus (Ehrenberg, 1832)) and the common bottlenose dolphin (Tursiops truncatus (Montagu, 1821)), including type specimens. The Burrunan dolphin (Tursiops australis Charlton-Robb, Gershwin, Thompson, Austin, Owen and McKechnie, 2011) fell well within T. truncatus for both 2D and 3DGM methods. Thirteen Tursiops spp. specimens, no T. australis specimens, were of intermediate size (2D) and could not be assigned to either species. For 3DGM data, there was a strong allometric influence and few non-allometric differences between species. Length and width of the cranium and rostrum were important discriminating variables. Tursiops aduncus was smaller, had more teeth, fewer vertebrae, and more erosion on the pterygoids and frontals than T. truncatus. Overall cranium shape was round in T. aduncus and angular in T. truncatus. Skull length of T. aduncus was smaller in low than in high latitudes. This study highlights the importance of large sample size, multiple analytical methods, and extensive geographical coverage when undertaking taxonomic studies.

Lingering Taxonomic Challenges Hinder Conservation and Management of Global Bonefishes

Despite expanding research on the popular recreational fishery, bonefish taxonomy remains murky. The genus Albula, comprising these iconic circumtropical marine sportfishes, has a complex taxonomic history driven by highly conserved morphology. Presently, 12 putative species are spread among 3 species complexes. The cryptic morphology hinders visual identification, requiring genetic species identification in some cases. Unclear nomenclature can have unintended consequences, including exacerbating taxonomic uncertainty and complicating resolution efforts. Further, ignoring this reality in publications may erode management and conservation efforts. In the Indian and Pacific oceans, ranges and areas of overlap are unclear, precluding certainty about which species support the fishery and hindering conservation efforts. Species overlap, at both broad and localized spatial scales, may mask population declines if one is targeted primarily (as demonstrated in the western Atlantic fishery). Additional work is necessary, especially to increase our understanding of spatiotemporal ecology across life history stages and taxa. If combined with increased capacity to discern between cryptic species, population structure may be ascertained, and fisheries stakeholders will be enabled to make informed decisions. To assist in such efforts, we have constructed new range maps for each species and species complex. For bonefishes, conservation genomic approaches may resolve lingering taxonomic uncertainties, supporting effective conservation and management efforts. These methods apply broadly to taxonomic groups with cryptic diversity, aiding species delimitation and taxonomic revisions.

Taxonomy Matters in Monitoring and EIA Studies: An Urgent Need to Revive Systematic and Taxonomy Research in India

Sanitha, S.K. and Madeswaran, P., 2020. Taxonomy matters in monitoring and EIA studies: An urgent need to revive systematic and taxonomy research in India. In: Sheela Nair, L.; Prakash, T.N.; Padmalal, D., and Kumar Seelam, J. (eds.), Oceanic and Coastal Processes of the Indian Seas. Journal of Coastal Research, Special Issue No. 89, pp. 71-76. Coconut Creek (Florida), ISSN 0749-0208.Human-induced loss of biodiversity is affecting the functions and services of the earth's ecosystems. Large regions of the biosphere are expected to be affected by the projected climate change, further aggravating the health of the ecosystems. It has been widely recognized that the successful management of any ecosystem cannot occur without an effective assessment of its regional biodiversity. However, monitoring or ecology studies exploring the relationship between biota and the environment have often overlooked the role of biodiversity. Since biodiversity is increasingly becoming an important component of ecosystem management, taxonomic accuracy is fundamental to prevent erroneous assessments and decisions in management and conservation policy. This paper therefore discusses how lack of taxonomy research is hindering marine monitoring and EIA studies in India. Here, we use the macrofaunal data from the Seawater Quality Monitoring (SWQM) program, the coastal monitoring program of India. We observed that the uncertainty in the biological data hampered a sound interpretation of the observed pattern, and is a major challenge to monitoring and EIA studies. Therefore, taxonomic uncertainty may lead to wrong conclusions and ultimately to inappropriate management plans.Four major difficulties in effective biodiversity studies in India were identified. These are (1) lack of experts; (2) lack of appropriate support and funding for biodiversity studies; (3) the need to update regional literature for identification of most marine invertebrates and (4) lack of interaction among Indian researchers. Given the slow progress in taxonomy research, particularly marine invertebrates, there is an urgent need for networking among the Indian and international scientists, effective training, and an integrated approach. Reliable taxonomy offers an opportunity to provide relevant information to policy makers and environmental managers for skillfully manage the marine systems.

Sharpening the DNA barcoding tool through a posteriori taxonomic validation: The case of Longitarsus flea beetles (Coleoptera: Chrysomelidae).

The accuracy of the DNA barcoding tool depends on the existence of a comprehensive archived library of sequences reliably determined at species level by expert taxonomists. However, misidentifications are not infrequent, especially following large-scale DNA barcoding campaigns on diverse and taxonomically complex groups. In this study we used the species-rich flea beetle genus Longitarsus, that requires a high level of expertise for morphological species identification, as a case study to assess the accuracy of the DNA barcoding tool following several optimization procedures. We built a cox1 reference database of 1502 sequences representing 78 Longitarsus species, among which 117 sequences (32 species) were newly generated using a non-invasive DNA extraction method that allows keeping reference voucher specimens. Within this dataset we identified 69 taxonomic inconsistencies using barcoding gap analysis and tree topology methods. Threshold optimisation and a posteriori taxonomic revision based on newly generated reference sequences and metadata allowed resolving 44 sequences with ambiguous and incorrect identification and provided a significant improvement of the DNA barcoding accuracy and identification efficacy. Unresolved taxonomic uncertainties, due to overlapping intra- and inter-specific levels of divergences, mainly regards the Longitarsus pratensis species complex and polyphyletic groups L. melanocephalus, L. nigrofasciatus and L. erro. Such type of errors indicates either poorly established taxonomy or any biological processes that make mtDNA groups poorly predictive of species boundaries (e.g. recent speciation or interspecific hybridisation), thus providing directions for further integrative taxonomic and evolutionary studies. Overall, this study underlines the importance of reference vouchers and high-quality metadata associated to sequences in reference databases and corroborates, once again, the key role of taxonomists in any step of the DNA barcoding pipeline in order to generate and maintain a correct and functional reference library.

Molecular diversity and species delimitation in the family Gasteruptiidae (Hymenoptera: Evanioidea).

Gasteruptiidae Ashmead is an easily recognised family of wasps with ∼589 described species worldwide. Although well characterised by traditional taxonomy, multiple authors have commented on the extreme morphological uniformity of the group, making species-level identification difficult. This problem is enhanced by the lack of molecular data and molecular phylogenetic research for the group. We used 187 cytochrome c oxidase subunit I (COI) barcodes to explore the efficiency of sequence data to delimitate species in Gasteruptiidae. We undertook a graphical and discussion-based comparison of six methods for species delimitation, with the success of methods judged based on known species boundaries and morphology. Both distance-based (ABGD and jMOTU threshold analysis) and tree-based (GMYC and PTP) methods compared across multiple parameters recovered variable molecular operational taxonomic units (MOTUs), ranging from 55 to 123 MOTUs. Tree-based methods tended to split known morphological species less than distance-based methods, with the single-threshold GMYC method the most concordant with known morphospecies. Our results suggest that the incorporation of molecular species delimitation techniques provides a powerful tool to assist in the interpretation of species and help direct informed decisions with taxonomic uncertainty in the family.

Resolving complicated relationships of the Panax bipinnatifidus complex in southwestern China by RAD-seq data

The P. binpinnatifidus complex included most of the Panax species distributed in Sino-Himalaya regions except for P. pseudoginseng, P. stipuleanatus and P. notoginseng. However, the delimitation and identification of these taxa within the species complex are very difficult due to the existence of morphological intermediates, and their evolutionary relationships remain unresolved despite several studies have been carried out based on traditional DNA markers. The taxonomic uncertainty hinders the identification, conservation and exploration of these wild populations of Panax. To study this species complex, we employed ddRAD-seq data of these taxa from 18 different localities of southwestern China, using two RAD analysis pipelines, STACKS and pyRAD. Based on the results of phylogenetic analysis, the species complex was divided into four clades with high supports, which largely agreed with morphologically described species. Two clades, corresponding to P. vietnamensis and P. zingiberensis, respectively, were sister groups, indicating that these two species had a closer genetic relationship; the third clade was consisted of samples with bamboo-like rhizomes named as P. wangianus clade, and the fourth one with moniliform rhizomes was named as P. bipinnatifidus clade. The population genetic structure analysis and D-statistics test showed the localized admixture among these species, which indicated that introgression had occurred among the related lineages continuously distributed in southeastern Yunnan and adjacent regions.

Re-examination of the cranial osteology of the Arctic Alaskan hadrosaurine with implications for its taxonomic status.

Hadrosaurid fossils from the Liscomb Bonebed (Prince Creek Formation, North Slope, Alaska) were the first dinosaur bones discovered from the Arctic. While the Prince Creek Formation hadrosaurids were long identified as Edmontosaurus, a member of the sub-clade Hadrosaurinae, they were recently assigned to a newly-erected taxon, Ugrunaaluk kuukpikensis. However, taxonomic status of the new taxon is ambiguous largely due to the immature nature of the specimens upon which it was based. Here we reexamine cranial elements of the Prince Creek Formation hadrosaurine in order to solve its taxonomic uncertainties. The Prince Creek Formation hadrosaurine possesses a short dorsolateral process of the laterosphenoid, one of the diagnostic characters of Edmontosaurus. The Prince Creek Formation hadrosaurine also shows affinity to Edmontosaurus regalis in the presence of a horizontal shelf of the jugal. Our morphological comparisons with other North American Edmontosaurus specimens and our phylogenetic analyses demonstrate that the Prince Creek Formation hadrosaurine should be re-assigned to Edmontosaurus. Because the Prince Creek Formation Edmontosaurus shows differences with lower latitude Edmontosaurus in a dorsoventrally short maxilla, presence of a secondary ridge on the dentary teeth, and the absence of the transverse ridge between basipterygoid processes of the basisphenoid, we consider that the Prince Creek Formation Edmontosaurus should be regarded as Edmontosaurus sp. until further discoveries of mature hadrosaurines from the Prince Creek Formation Bonebed and/or equivalently juvenile Edmontosaurus specimens from the lower latitudes allow direct comparisons. The retention of the Prince Creek Formation hadrosaurine as Edmontosaurus re-establishes a significant latitudinal distribution for this taxon. Despite the large latitudinal distribution of the taxon, the morphological disparity of Edmontosaurus is small within Hadrosaurinae. The small morphological disparity may be related to the relatively low latitudinal temperature gradient during the latest Cretaceous compared to present day, a gradient which might not have imposed significant pressure for much morphological adaptations across a broad latitudinal range.

Cranial variability and differentiation among golden jackals (Canis aureus) in Europe, Asia Minor and Africa.

Golden jackal (Canis aureus) expansion in the last decades has triggered research interest in Europe. However, jackal phylogeny and taxonomy are still controversial. Morphometric studies in Europe found differences between Dalmatian and the other European jackals. Recent genetic studies revealed that African and Eurasian golden jackals are distinct species. Moreover, large Canis aureus lupaster may be a cryptic subspecies of the African golden jackal. Although genetic studies suggest changes in Canis aureus taxonomy, morphological and morphometric studies are still needed. The present study proposes the first comprehensive analysis on a wide scale of golden jackal skull morphometry. Extensive morphometric data of jackal skulls from Europe (including a very large Bulgarian sample), Asia Minor, and North Africa were analysed, by applying recently developed statistical tools, to address the following questions: (i) is there geographic variation in skull size and shape among populations from Europe, Anatolia and the Caucasus?, (ii) is the jackal population from the Dalmatian coast different?, and (iii) is there a clear distinction between the Eurasian golden jackal (Canis aureus) and the African wolf (Canis lupaster sensu lato), and among populations of African wolves as well? Principal component analysis and linear discriminant analysis were applied on the standardized and log-transformed ratios of the original measurements to clearly separate specimens by shape and size. The results suggest that jackals from Europe, Anatolia and the Caucasus belong to one subspecies: Canis aureus moreotica (I. Geoffroy Saint-Hilaire, 1835), despite the differences in shape of Dalmatian specimens. The present study confirmed morphometrically that all jackals included so far in the taxon Canis aureus sensu lato may represent three taxa and supports the hypothesis that at least two different taxa (species?) of Canis occur in North Africa, indicating the need for further genetic, morphological, behavioural and ecological research to resolve the taxonomic uncertainty. The results are consistent with recent genetic and morphological studies and give further insights on golden jackal taxonomy. Understanding the species phylogeny and taxonomy is crucial for the conservation and management of the expanding golden jackal population in Europe.

Genetic variation and phylogenetic relationships of Thelymitra javanica (Orchidaceae: Orchidoideae) in East and Central Java, Indonesia

Abstract. Wijaya IMS, Daryono BS, Purnomo. 2020. Genetic variation and phylogenetic relationships of Thelymitra javanica Blume (Orchidaceae: Orchidoideae) in East and Central Java, Indonesia. Biodiversitas 21: 1174-1181. Thelymitra J.R. Forst & G. Forst is a terrestrial orchid genera and mainly distributed in Australia as a center of its diversification. Moreover, Thelymitra javanica Blume is the only species of Thelymitra found in Asia, especially in Indonesia. In Australia and New Zealand, most of Thelymitra species easily found in lowland, whereas, T. javanica in Indonesia preferred to grows near the peaks of mountains around 2,000-3,000 m asl. The high altitude correlated with high light intensity and lower soil nutrients which require specific adaptation of plant to survive. The wide range of adaptation could be due to the presence of genetic variability among populations of Thelymitra. Therefore, this study was carried out to assess the genetic variability and phylogenetic relationships of T. javanica in East and Central Java. The genetic variability of Thelymitra was evaluated by molecular approaches, which is preferably utilized to determine the plant taxonomy to establish the taxonomic uncertainties. ITS-nrDNA is a popular DNA marker that widely used in phylogenetic study among various taxa. Sequences were analyses using Maximum Likelihood method with 11 in-group, 6 interspecies out-group of Thelymitra, and 2 intergeneric out-group of Thelymitrinae subtribe. The result showed that ITS-nrDNA sequences of T. javanica have no variation in nucleotide compositions and showing polytomy branch in cladogram. Thelymitra javanica also has a close relationship with Thelymitra longifolia J.R. Forst & G. Forst that are endemic to New Zealand.

Morphological variation and sexual dimorphism in the Aspidoscelis gularis complex (Squamata: Teiidae) from Mexico

AbstractMorphological variation can be promoted by ecological factors and the evolutionary history of the taxa. The Aspidoscelis gularis complex is one of the groups of whiptail lizards that exhibits one of the widest distributions in North America, occupying a great variety of environments. Its members are similar in morphology, which has contributed to the taxonomic uncertainty in the group. In this study, variation in size and head shape was analysed considering a phylogenetic hypothesis based on the Cytb and ND2 mitochondrial genes. Six evolutionarily significant units were found, of which the morphological patterns were analysed. Eleven morphological characters and two landmark configurations of the head were used. Analysis of size revealed a pattern of sexual dimorphism, while geometric morphometrics suggested that there is no dimorphism in head shape. Neither size nor shape shows unique patterns of morphological variation between the evolutionarily significant units, which could be attributed to morphological conservatism and recurrent hybridization in whiptails.

Genetic diversity and morphological variation in African boxthorn (Lycium ferocissimum) – Characterising the target weed for biological control

Lycium ferocissimum (African boxthorn) is a Weed of National Significance in Australia. Biological control may have potential to manage this weed, but taxonomic uncertainty needs to be addressed first to facilitate searches for potential agents. We sampled putative L. ferocissimum (i.e. tentatively identified morphologically in the field) across its native range in South Africa and introduced range in Australia. Morphometric and genetic analyses were conducted to confirm the species identity of these samples, and to assess morphological and genetic variation across both ranges. All samples collected in Australia were confirmed as L. ferocissimum, with no evidence of hybridisation with any other Lycium species. Nuclear and chloroplast genetic diversity within L. ferocissimum across both South Africa and Australia was low, with no evidence of genetic structure. One of the two common chloroplast haplotypes found across Australia was found at only two sites in South Africa, both near Cape Town, suggesting that the Australian lineage may have originated from this region. Ten samples from South Africa putatively identified in the field as L. ferocissimum were genetically characterised as different (unidentified) Lycium species. Our morphometric analyses across different Lycium species in South Africa did not identify any leaf or floral characteristics unique to L. ferocissimum, and thus morphological identification of the latter species in its native range may remain problematic. To ensure the correct Lycium species is surveyed for candidate biological control agents we suggest that individuals should be permanently tagged and putative morphological determinations supplemented with genetic analyses to confirm species identity.

Comparison of Wing, Ovipositor, and Cornus Morphologies between Sirex noctilio and Sirex nitobei Using Geometric Morphometrics.

Sirex noctilio F. (Hymenoptera: Siricidae) is an invasive woodwasp from Europe and North Africa. Globalization has led to an expanding global presence in pine forests. S. noctilio has been previously introduced outside of its native range and now co-occurs in trees with native S. nitobei Matsumura (first discovered in 2016). Damage to Pinus sylvestris var. mongolica Litv in northeast China can be attributed to two types of woodwasp. To distinguish the two species by the traditional taxonomic morphology, we mainly differentiate the color of the male’s abdomen and the female’s leg. There remains intraspecific variation like leg color in the delimitation of related genera or sibling species of Sirex woodwasps. In this study, we used landmark-based geometric morphometrics including principal component analysis, canonical variate analysis, thin-plate splines, and cluster analysis to analyze and compare the wings, ovipositors, and cornus of two woodwasps to ascertain whether this approach is reliable for taxonomic studies of this group. The results showed significant differences in forewing venation and the shapes of pits in the middle of ovipositors among the two species, whereas little difference in hindwings and cornus was observed. This study assists in clarifying the taxonomic uncertainties of Siricidae and lays a foundation for further studies of the interspecific relationships of the genus Sirex.

Integrative systematics unveils the controversial identity of Engraulidae fishing stocks in a Neotropical estuary, northeast Brazil

ABSTRACT In Brazil, the use and diversity of the common names of fish species, coupled with taxonomic uncertainties, hinder the reliability of fishing statistical data. In this scenario, there are the so-called pilombetas of the São Francisco River, an important fishing resource in region. Despite its importance, the real diversity of species identified in the area remains obscure. In order to properly identify and delimit the species popularly known as pilombetas, an integrative approach involving traditional taxonomy, geometric morphometrics and molecular systematics was applied. Results from geometric morphometrics and molecular analyses were consistent with the results of the traditional morphological analysis, also indicating the delimitation of six taxa belonging to Engraulidae in the lower São Francisco River. In addition, species delimitation methods revealed an intrapopulation genetic divergence of 1.7% for Lycengraulis grossidens. The results revealed that the currently known richness species of Engraulidae in the studied area has been underestimated. Thus, an updated taxonomic key is herein proposed for the Engraulidae species from the lower São Francisco River and estuary. The integrative analysis approach revealed to be effective to address taxonomic questions and help the management of stocks, ensuring the maintenance of local diversity of fishes in the Neotropical region.

Controversial taxonomy of hemp

Hemp (Cannabis sativa L.) was one of the earliest domesticated plant species. Biological classification (taxonomy or systematization) manifests evolutional relationships between taxons according to trait similarities. When it comes to taxonomy, hemp is one of the most controversial plant species due to significant effects of environmental conditions on hemp phenology and expression of quantitative traits as well as different levels of gender expression observed in hemp plants. Controversial taxonomy of hemp has gone through several phases throughout history. The attitude on the number of species within the genus Cannabis and the criteria used in taxonomic units division were under dispute. Initially focused on morphological characteristics and geographical origin, the approach was greatly amended by the development of molecular and biochemical techniques. The main cause of taxonomic uncertainties is the inbreeding ability of all wild Cannabis populations, resulting in continual variability of quantitative traits. The aim of the paper is to review the history of Cannabis classification including different approaches to this scientific issue.

Novel sexual dimorphism in a new genus of Bathynellidae from Russia, with a revision of phylogenetic relationships

AbstractBathynellidae is the neglected family of Bathynellacea, a groundwater group of crustaceans with 33 genera and 107 species described and almost half of them included in the ‘catch‐all’ genus Bathynella. Due to the morphological homogeneity of the species, the taxonomic uncertainties have accumulated over time. Therefore, to explore the phylogenetic relationships among taxa, a combined approach using morphological and molecular data is needed. In this paper, we performed a phylogenetic analysis based on partial sequences of COI and 18S including 30 species of Bathynellidae. This data set represents the most updated one, including a new genus and a new species (Altainella calcarata gen. n. sp. n.) of Bathynellidae described here from Altai Mountain (Russia). The new taxon presents a new type of sexual dimorphisms with a peculiar structure on the coxopod of the male thoracopod VII and also sexual dimorphism on the mandibular palp, as some species of the subfamily Gallobathynellinae. This is the first species of Bathynellidae that presents both variants of sexual dimorphism. The molecular phylogeny supports the morphology and the erection of the new genus and displays highly divergent genetic units corresponding to subfamilies, with the new genus closer to Bathynellinae genera than other subfamilies. With the description of this new species and its molecular characterization, the existence of the other genera beyond Bathynella is confirmed in Eurasia.

Multilocus phylogenetic analysis helps to untangle the taxonomic puzzle of chubs (genus Squalius: Cypriniformes: Actinopteri) in the Adriatic basin of Croatia and Bosnia and Herzegovina

AbstractFish of the genus Squalius inhabit various freshwater habitats across Europe and Asia, with a particularly high diversity in the Mediterranean area, but the taxonomic status of many populations is still a matter of debate. This study aims to resolve the taxonomic uncertainties of chubs distributed in the Adriatic basin of Croatia and Bosnia and Herzegovina. Phylogenetic reconstruction based on the mitochondrial gene for cytochrome b and two nuclear genes, the recombination activating gene 1 and the rhodopsin gene, reveal high diversity of chubs in the investigated area. Two evolutionary independent groups are revealed: the first comprising the species Squalius illyricus, S. microlepis, S. svallize, S. tenellus and S. zrmanjae, and a second group corresponding with S. squalus. Genetic distinctiveness of species belonging to different groups is high due to their divergence that began in the Middle Miocene. In addition to allopatric speciation as the main force of divergence of Adriatic Squalius species, several instances of natural hybridizations were detected, contributing to the observed diversity. A comparison of phylogenetic scenarios using Bayesian factors corroborated the molecular basis for recognition of six Squalius species in the Adriatic basin, while Squalius janae is confirmed to be a junior synonym of S. squalus.

Untangling the taxonomy of the Cladrastis clade (Leguminosae: Papilionoideae) by integrating phylogenetics and ecological evidence

AbstractThe Cladrastis clade is an early‐diverged lineage within the subfamily Papilionoideae of Leguminosae. Several taxonomic uncertainties limit a robust understanding of its taxonomy: (1) Should the genus Platyosprion be resurrected? (2) How should Cladrastis be delimited to maintain the generic monophyly? (3) Is Styphnolobium best classified into two or three sections? We assessed specific/sectional/generic boundaries within this clade by integrating evidence from phylogenetic analyses, morphology, and multivariate ecological methods. With an extensive sampling of the clade, we reconstructed the phylogenies using nrDNA (ITS) and plastid DNA regions (matK, psbA‐trnH, trnL‐F). Based on environmental data for 841 occurrences, clusters of species were sought according to their environmental preferences with the principal component analysis (PCA), and explicit hypotheses on species/sectional boundaries were tested using ecological niche modeling (ENM). A new tribe, Cladrastideae, is established based on the Cladrastis clade with four monophyletic groups: the Cladrastis platycarpa complex, Cladrastis s.str., Pickeringia and Styphnolobium. The C. platycarpa complex constitutes the resurrected genus Platyosprion. The putative species C. chingii, C. parvifolia, C. scandens and C. yungchunii are suggested to be treated as synonyms of Platyosprion platycarpum. Cladrastis is recircumscribed as equal to Cladrastis s.str., with three species from eastern Asia, and one species, C. kentukea, from eastern North America. Styphnolobium is herein classified into three sections: St. sect. Oresbios, St. sect. Styphnolobium and a new section, St. sect. Affine.