Taxonomic Entities Research Articles

Molecular phylogeny of the Palaearctic butterfly genus Pseudophilotes (Lepidoptera: Lycaenidae) with focus on the Sardinian endemic P. barbagiae

BackgroundThe Palaearctic butterfly genus Pseudophilotes Beuret, 1958 (Lycaenidae: Polyommatinae), that today occurs in North Africa and in Eurasia, includes ten described species with various distribution ranges, including endemics such as the Sardinian P. barbagiae. Phylogenetic relationships among these species are largely unresolved. In the present study, we analysed 158 specimens, representing seven species out of ten described in the genus, from widely distributed sites throughout the western Palaearctic region, using nuclear markers (28S rRNA, wingless, Internal Transcribed Spacer 2 and Elongation Factor 1α) and the barcoding region of the mitochondrial cytochrome c oxidase subunit 1 gene to investigate if the current taxonomic entities match the phylogenetic pattern. Further, we attempt to infer the geographic origin of the genus Pseudophilotes and estimate the timing of its radiations, including the split of the Sardinian endemic P. barbagiae.ResultsMaximum Likelihood and Bayesian inference analyses confirmed the monophyly of the genus Pseudophilotes and clearly supported the closer affinity of P. barbagiae to the species assemblage of P. baton, P. vicrama and P. panoptes as opposed to P. abencerragus. The currently accepted species P. baton, P. vicrama and P. panoptes turned out to be weakly differentiated from each other, while P. bavius and P. fatma emerged as highly distinct and formed a well supported clade. The split between the lineage comprising bavius and fatma (sometimes treated as a distinct genus, Rubrapterus) with Salvia species as larval host plants, and the remaining Pseudophilotes that utilize Thymus and other Lamiaceae (but not Salvia), dates back to about 4.9 million years ago (Mya).ConclusionsOur results show that the last common ancestor of the genus probably lived in the Messinian period (5.33–7.25 Mya). At species level, they support the current taxonomy of the genus, although P. panoptes, P. baton and P. vicrama display complex patterns based on phylogeographic relationships inferred from mtDNA. The Sardinian endemic P. barbagiae turned out to be a young endemic, but clearly with European instead of North African origin and evolved through allopatric isolation on the island of Sardinia only about 0.74 Mya.

Flexible metagenome analysis using the MGX framework

BackgroundThe characterization of microbial communities based on sequencing and analysis of their genetic information has become a popular approach also referred to as metagenomics; in particular, the recent advances in sequencing technologies have enabled researchers to study even the most complex communities.Metagenome analysis, the assignment of sequences to taxonomic and functional entities, however, remains a tedious task: large amounts of data need to be processed. There are a number of approaches addressing particular aspects, but scientific questions are often too specific to be answered by a general-purpose method.ResultsWe present MGX, a flexible and extensible client/server-framework for the management and analysis of metagenomic datasets; MGX features a comprehensive set of adaptable workflows required for taxonomic and functional metagenome analysis, combined with an intuitive and easy-to-use graphical user interface offering customizable result visualizations. At the same time, MGX allows to include own data sources and devise custom analysis pipelines, thus enabling researchers to perform basic as well as highly specific analyses within a single application.ConclusionsWith MGX, we provide a novel metagenome analysis platform giving researchers access to the most recent analysis tools. MGX covers taxonomic and functional metagenome analysis, statistical evaluation, and a wide range of visualizations easing data interpretation. Its default taxonomic classification pipeline provides equivalent or superior results in comparison to existing tools.

Multivariate morphometric analysis of Petrorhagia subsect. Saxifragae (Caryophyllaceae) in Greece, with a new species from SE Peloponnisos: P. laconica

Abstract: The intra-generic relationships within the intriguing genus Petrorhagia are currently debated, as the genus is underrepresented in recent taxonomic studies. In this study, we investigate the relationships among the species of Petrorhagia [sect. Petrorhagia] subsect. Saxifragae occurring in Greece. Based on a combination of ordination methods and discriminant analyses of 36 macromorphological characters, five species are recognized in Greece. The analyses showed that all currently known species from Greece (P. fasciculata, P. graminea, P. phthiotica and P. saxifraga) represent distinct taxonomic entities. According to our results, two recently collected populations from SE Peloponnisos represent a fifth, new Petrorhagia species, which is first described and illustrated here as P. laconica. It is related to the widespread P. saxifraga and the Greek endemic P. graminea, but clearly distinct from both species by a combination of morphological characters, including indumentum, inflorescence, calyx, c...

Phyllanthus rufuschaneyi: a new nickel hyperaccumulator from Sabah (Borneo Island) with potential for tropical agromining

BackgroundNickel hyperaccumulator plants are of much interest for their evolution and unique ecophysiology, and also for potential applications in agromining—a novel technology that uses plants to extract valuable metals from soil. The majority of nickel hyperaccumulators are known from ultramafic soils in tropical regions (Cuba, New Caledonia and Southeast Asia), and one genus, Phyllanthus (Phyllanthaceae), is globally the most represented taxonomic entity. A number of tropical Phyllanthus-species have the potential to be used as ‘metal crops’ in agromining operations mainly because of their ease in cultivation and their ability to attain high nickel concentrations and biomass yields.ResultsOne of the most promising species globally for agromining, is the here newly described species Phyllanthus rufuschaneyi. This species can be classified in subgenus Gomphidium on account of its staminate nectar disc and pistillate entire style and represents the most western species of this diverse group. The flower structure indicates that this species is probably pollinated by Epicephala moths.ConclusionsPhyllanthus rufuschaneyi is an extremely rare taxon in the wild, restricted to Lompoyou Hill near Kinabalu Park in Sabah, Malaysia. Its utilization in agromining will be a mechanism for conservation of the taxon, and highlights the importance of habitat and germplasm preservation if rare species are to be used in novel green technologies.

Utility of taxon-specific molecular markers for the species identification of herbarium specimens: an example from Desmarestia japonica (Phaeophyceae, Desmarestiales) in Korea

Desmarestia japonica (Phaeophyceae, Desmarestiales) was recently established from the Japanese ligulate Desmarestia and is morphologically similar to D. ligulata. This species has been reported only from Japan. However, the taxonomic reports based on additional regional distributions are needed to clarify this taxonomic entity and its species boundaries. Because Desmarestia species have restricted distributions in Korea, we reexamined herbarium specimens of D. ligulata deposited at the National Institute of Biological Resources (South Korea). To improve the amplification efficiency of the polymerase chain reaction and avoid contamination by the DNA of other organisms, we developed taxon-specific molecular markers suitable for DNA barcoding of Desmarestia species. Nuclear ribosomal small subunit RNA (18S rDNA) and mitochondrial cytochrome c oxidase 1 (cox1) regions were selected as target DNA. As a result, both were successfully isolated from herbarium specimens of D. japonica acquired over 10 years. These molecular markers provide useful genetic information for herbarium specimens for which conventional molecular analysis is challenging.

Eukaryotic Plankton Species Diversity in the Western Channel of the Korea Strait using 18S rDNA Sequences and its Implications for Water Masses

Organisms entering the East Sea (Sea of Japan) through the Korea Strait, together with water, salt, and energy, affect the East Sea ecosystem. In this study, we report on the biodiversity of eukaryotic plankton found in the Western Channel of the Korea Strait for the first time using small subunit ribosomal RNA gene (18S rDNA) sequences. We also discuss the characteristics of water masses and their physicochemical factors. Diverse taxonomic groups were recovered from 18S rDNA clone libraries, including putative novel, higher taxonomic entities affiliated with Cercozoa, Raphidophyceae, Picozoa, and novel marine Stramenopiles. We also found that there was cryptic genetic variation at both the intraspecific and interspecific levels among arthropods, diatoms, and green algae. Specific plankton assemblages were identified at different sampling depths and they may provide useful information that could be used to interpret the origin and the subsequent mixing history of the water masses that contribute to the Tsushima Warm Current waters. Furthermore, the biological information highlighted in this study may help improve our understanding about the complex water mass interactions that were highlighted in the Korea Strait.

Variation in chromosome number and breeding systems: implications for diversification in Pachycereus pringlei (Cactaceae).

Polyploidy, the possession of more than two sets of chromosomes, is a major biological process affecting plant evolution and diversification. In the Cactaceae, genome doubling has also been associated with reproductive isolation, changes in breeding systems, colonization ability, and speciation. Pachycereus pringlei (S. Watson, 1885) Britton & Rose, 1909, is a columnar cactus that has long drawn the attention of ecologists, geneticists, and systematists due to its wide distribution range and remarkable assortment of breeding systems in the Mexican Sonoran Desert and the Baja California Peninsula (BCP). However, several important evolutionary questions, such as the distribution of chromosome numbers and whether the diploid condition is dominant over a potential polyploid condition driving the evolution and diversity in floral morphology and breeding systems in this cactus, are still unclear. In this study, we determined chromosome numbers in 11 localities encompassing virtually the entire geographic range of distribution of P. pringlei. Our data revealed the first diploid (2n = 22) count in this species restricted to the hermaphroditic populations of Catalana (ICA) and Cerralvo (ICE) Islands, whereas the tetraploid (2n = 44) condition is consistently distributed throughout the BCP and mainland Sonora populations distinguished by a non-hermaphroditic breeding system. These results validate a wider distribution of polyploid relative to diploid individuals and a shift in breeding systems coupled with polyploidisation. Considering that the diploid base number and hermaphroditism are the proposed ancestral conditions in Cactaceae, we suggest that ICE and ICA populations represent the relicts of a southern diploid ancestor from which both polyploidy and unisexuality evolved in mainland BCP, facilitating the northward expansion of this species. This cytogeographic distribution in conjunction with differences in floral attributes suggests the distinction of the diploid populations as a new taxonomic entity. We suggest that chromosome doubling in conjunction with allopatric distribution, differences in neutral genetic variation, floral traits, and breeding systems has driven the reproductive isolation, evolution, and diversification of this columnar cactus.

Pest categorisation of Toxoptera citricida.

The European Commission requested EFSA to conduct a pest categorisation of Toxoptera citricida (Hemiptera: Aphididae), an oligophagous aphid developing and reproducing parthenogenetically on tender leaf and flower flush of citrus (Rutaceae). T. citricida is a taxonomic entity with reliable methods available for detection and identification. It is regulated in the EU by Council Directive 2000/29/EC where it is listed in Annex IIAI as a harmful organism whose introduction and spread into the EU shall be banned. T. citricida is native to tropical regions of Southeast Asia and has spread to most citrus‐growing areas worldwide, except California and the Mediterranean basin, causing significant damage to citrus as it is the most efficient vector of the Citrus tristeza virus (CTV). T. citricida occurs in Madeira and, with a restricted distribution, in the north‐west of the Iberian Peninsula, mostly on backyard citrus trees. This may have hindered the effectiveness of the official control measures in these areas. There are further phytosanitary measures in place in the EU in order to limit entry via traded commodities. Citrus plants for planting are regulated and are a closed pathway. However, there is uncertainty regarding host status of some non‐rutaceous plants on which this aphid has been recorded and so other plant genera may provide additional pathways. The EFSA Plant Health Panel concludes that the establishment of T. citricida in the main EU citrus growing areas around the Mediterranean would have significant impacts because of its ability to vector CTV. Considering the criteria within the remit of EFSA to assess the status as a potential Union quarantine pest (QP), as a potential protected zone quarantine pest (PZQP) or as a potential regulated non‐quarantine pest (RNQP), T. citricida meets with no uncertainties the criteria assessed by EFSA for consideration as a potential Union QP.

DNA barcoding and faunistic criteria for a revised taxonomy of Italian Ephemeroptera

Mayfly (Ephemeroptera) systematics has considerably changed over the years, but many questions have yet to be answered. The synergistic connection between traditional knowledge and new data sources, producing increasingly complex information, has become a compelling issue for modern taxonomy. Molecular tests and the use of reliable reference sequence libraries may constitute effective complements to the traditional method in guiding recognition of species and giving information about taxonomic incongruences which require further examination. In the present study, we sought to verify the current Italian mayfly nomenclatural system through DNA barcoding and relevant points to reliably manage the available amount of morpho-ecological and molecular data are discussed. We investigated COI (Cytochrome oxidase I) sequence variation in 163 individuals of Italian mayflies, 126 of which were previously assigned to 24 morphologically recognised species, and 37 could be attributed only to generic taxonomic entities (“sp.”, “cf.” or “gr.”). DNA barcoding statistical tests for species delimitation hypotheses based on genetic distances and inferred gene trees were integrated with GenBank searches and surveys of the historical literature to better understand the knowledge acquired on the status and diversity of the investigated taxa. Combined criteria to define three categories of reliability were then assessed. Concurrent data allowing unambiguous identification were attained for only eight species. High intraspecific genetic distances (> 3%) and a lack of reliable reference material or convincing taxonomic information evidenced 29 critical states, deserving further investigation. Solid species names, potential cryptic species and entities about which little is known are pointed out for a future upgrade/reorganisation of the taxonomy of Italian Ephemeroptera.

Anatomía foliar comparada de <i>Gaiadendron punctatum</i> y <i>Tripodanthus belmirensis</i> (Loranthacea)

Se describe la anatomía foliar de las especies Gaiadendron punctatum y Tripodanthus belmirensis, al objeto de estudiar posibles caracteres que permitan una identificación precisa de estos dos géneros de la familia Loranthaceae, de hábito arbustivo o arbóreo. Las muestras se procesaron y sometieron a tinción con técnicas clásicas para su observación al microscopio óptico. Ambas especies presentaron similitudes como una epidermis monoestratificada y estomas de tipo rubiáceo. Sin embargo, se observó una composición anatómica claramente diferenciada en aspectos como el mesófilo, forma y ubicación de las células epidérmicas y la presencia de acumulaciones de súber en G. punctatum o idioblastos abundantes en T. belmirensis. Se construyó una clave dicotómica para la determinación de especies con base en caracteres anatómicos de la hoja entre las especies del género Tripodanthus y G. punctatum, además se discute brevemente el uso de caracteres anatómicos en la determinación y soporte de entidades taxonómicas diferenciables dentro de la familia Loranthaceae.

Cistus ladanifer (Cistaceae): a natural resource in Mediterranean-type ecosystems.

Cistus ladanifer has a well-defined taxonomic identity. 2,2,6-trimethylcyclohexanone may be an authenticity and taxonomic marker. Its traits and applications make it a possible economic resource fitted for Mediterranean areas. Cistus ladanifer is a dominant shrub species endemic to the western Mediterranean region. Due to its dominant nature and its potential ecological, aromatic or pharmacological applications, C. ladanifer has been the object of numerous studies. In this review current knowledge on different aspects of this species is summarized, from its taxonomy to its chemical characterisation or its competitive traits. There are no doubts about the taxonomic entity of C. ladanifer, although the recognition of infraspecific taxa deserves more attention. Given that the fragrant exudate of C. ladanifer holds a very specific composition, one species specific carotenoid, 2,2,6-trimethylcyclohexanone, derivative is proposed as an authenticity marker for uses of C. ladanifer in pharmacological or aromatic industries. Evidence is also gathered on the extreme adaptation of C. ladanifer to stressful conditions in the Mediterranean region, such as the ability to survive in low hydric and high solar exposition conditions, presistence in poor and contaminated soils, and growth inhibition of several other plants through the release of allelochemicals. Thus, the finding of potential applications for this plant may contribute to enhance the economic dimension of derelict lands, such as mine tailings or poor agricultural Mediterranean areas.

Pest categorisation of Anthonomus grandis.

The European Commission requested EFSA to conduct a pest categorisation of Anthonomus grandis (Coleoptera: Curculionidae), an oligophagous pest weevil feeding on Malvaceae, including Gossypium spp., Hampea spp., Cienfuegosia spp. and Hibiscus pernambucensis. Marginal reproduction has also been observed on the ornamental Hibiscus syriacus. A. grandis is a taxonomic entity with reliable methods available for identification. It is regulated in the EU by Council Directive 2000/29/EC where it is listed in Annex IIB as a harmful organism whose introduction into EU Protected Zones (PZ) (Greece and the Spanish Communities of Andalusia, Catalonia, Extremadura, Murcia and Valencia) is regulated. A. grandis is native to tropical regions of Mesoamerica and has spread to other cotton‐growing areas in the Americas, from the USA to Argentina, causing significant damage to this crop. An eradication programme is in progress in the USA and has been successful in 16 previously infested states. In the EU, phytosanitary measures are in place in order to limit entry via traded commodities. Cotton seeds and fruit, as well as unginned cotton are currently regulated for the PZ but remain a potential pathway. Furthermore, ornamental Malvaceae (e.g. Hibiscus spp.) originating in infested areas may provide additional pathways. The EFSA Plant Health Panel concludes that A. grandis could establish and spread in the cotton‐growing areas of southern EU. Considering the criteria within the remit of EFSA to assess the status as a potential Union quarantine pest (QP), as a potential protected zone quarantine pest (PZQP), or as a potential regulated non‐quarantine pest (RNQP), A. grandis satisfies with no uncertainties the criteria to be regarded as a Union QP. However, it does not meet the criterion of occurrence in the EU territory (for PZQP) plus that of plants for planting being the principal means of spread (for RNQP).

Reappraisal of Campanula rotundifolia var. bulgarica Nejceff—a neglected taxon from Central Stara Planina Mountain, Bulgaria

Campanula rotundifolia var. bulgarica Nejceff, a neglected taxon in the Bulgarian flora with currently uncertain status, was collected and studied at its locus classicus in the Sokolna (Koru Dere) Reserve of Central Stara Planina Mountain. A detailed morphological analysis of Nejceff’s original material and other related species clearly indicates that this is a distinct taxonomic entity worthy of species rank. Campanula nejceffii, stat. nov. is distinguished by a combination of its pubescent habit, ovoid to elliptic-lanceolate cauline leaves, clearly spreading to reflexed narrowly triangular-lanceolate calyx teeth, erect buds and flowers. Complete species description and comparison with selected species in the C. rotundifolia group are given. The lectotypes of two taxa—C. rotundifolia var. bulgarica Nejceff and C. rotundifolia subsp. neicevii f. pirinica Stoj. & Acht. are designated by the authors.

Pest categorisation of Pucciniapittieriana.

The Panel on Plant Health performed a pest categorisation of Puccinia pittieriana, the causal agent of common rust of potato, for the EU. The pathogen is a single taxonomic entity and reliable methods exist for its detection and identification. Cultivated potato (Solanum tuberosum) and tomato (Solanum lycopersicum) are the main hosts of P. pittieriana. Some wild solanaceous plants can also be affected by the pathogen. P. pittieriana is present in countries of South and Central America (most commonly at elevations of 3,000–4,000 m), but uncertainty exists about its presence in Bolivia and Paraguay. The pathogen is not known to occur in the EU and is listed in Annex IIAI of Directive 2000/29/EC. P. pittieriana could potentially enter the EU mainly on living host plants and infested soil attached to potato tubers originated in infested areas. Potato and tomato crops are widely distributed in the EU and the prevailing climatic conditions, at least in part of the risk assessment area, are suitable for the establishment and spread of the pathogen. There is uncertainty on the yield/quality losses currently caused by the pathogen in the infested areas. Nevertheless, it is expected that the introduction and spread of P. pittieriana in the EU could impact potato and tomato production, although the magnitude is unknown. Cultural practices and chemical measures may reduce the inoculum sources but they cannot eliminate the pathogen. Phytosanitary measures are available to mitigate the risk of introduction and spread of the pathogen in the EU. P. pittieriana meets all the criteria assessed by EFSA for consideration as a potential Union quarantine pest. As P. pittieriana is not known to occur in the EU, this criterion assessed by EFSA to consider it as a Union regulated non‐quarantine pest is not met.

Toxonomic novelties in south brazilian amaryllidaceae-I: Hippeastrum ramboi new species from Rio Grande do sul and lectotypification of H. Breviflorum herb

Hippeastrum ramboi , a new species of Amaryllidaceae (Amaryllidoideae, Hippeastreae) endemic to the mountainous region of Rio Grande do Sul (Brazil) is described and illustrated. Data one its habitat, cology, geographic distribution is provided and its threat status is evaluated according to IUCN criteria. The new species has morphological affinity with H. sanctaecatharinae and H. breviflorum , the last one has not been correctly typified up to date, being lectotyped here to correctly define the circumscription of this taxonomic entity in comparison to the new species.

Integrating 2D and 3D shell morphology to disentangle the palaeobiology of ammonoids: a virtual approach

AbstractBased on data derived from computed tomography, we demonstrate that integrating 2D and 3D morphological data from ammonoid shells represents an important new approach for investigating the palaeobiology of ammonoids. Characterization of ammonite morphology has long been constrained to 2D data, with only a few studies collecting ontogenetic data in 180° steps. Here we combine this traditional approach with 3D data collected from high‐resolution nano‐computed tomography. Ontogenetic morphological data on the hollow shell of a juvenile ammonite Kosmoceras (Jurassic, Callovian) was collected. 2D data was collected in 10° steps and show significant changes in shell morphology. Preserved hollow spines show multiple mineralized membranes never reported before, representing temporal changes in the ammonoid mantle tissue. 3D data show that chamber volumes do not always increase exponentially, as was generally assumed, but may represent a proxy for life events, such as stress phases. Furthermore, chamber volume cannot be simply derived from septal spacing in forms comparable to Kosmoceras. Vogel numbers represent a 3D parameter for chamber shape, and those for Kosmoceras are similar to other ammonoids (Arnsbergites, Amauroceras) and modern cephalopods (Nautilus, Spirula). Two methods to virtually document the suture line ontogeny, used to document phylogenetic relationships of larger taxonomic entities, were applied for the first time and present a promising alternative to hand drawings. The curvature of the chamber surfaces increases during ontogeny due to increasing strength of ornamentation and septal complexity. As this may allow for faster handling of cameral liquid, it could compensate for decreasing SA/V ratios through ontogeny.

An atlas of orchids distribution in the Campania region (Italy), a citizen science project for the most charming plant family

A database of the orchids of Campania has been built up since 2000 with data collected for academic purposes, research projects and, more recently, with the contributions of enthusiastic amateurs and scholars, thus becoming a real citizen science project leading to the realization of an online Atlas (http://www.floracampana.unina.it/Orchidee/index.html). In this paper, the collection and storage of the data and the synthesis of them are presented. On 31 December 2016, the database accounted for 14680 records from more than 30 contributors relating to 126 taxonomic entities (species, subspecies, hybrids and a few “sensu lato”). The bibliographic records number 3663 (24.9%) and cover a time range of four centuries (from 1616 to 2016). Amongst the 11017 field records (observations), more than 99% are geo-referred and are “punctual” type (precision less than 100 m). The spatial and temporal distribution of the data has been analysed and biases have been underlined. The observations show a clear difference in the study effort year by year but always with a significant contribution of the citizen scientists. The analysis of the spatial distribution shows that the observations are preferably collected in protected areas, around main roads and on the roadsides. Many cells of the grid still lack information and these should be the object of future research.

Extinction Risk of Western North American Freshwater Mussels: Anodonta Nuttalliana, the Anodonta Oregonensis/Kennerlyi Clade, Gonidea Angulata, and Margaritifera Falcata

The recent declines in eastern North American species of freshwater mussels have been well documented, but the status of western species has been comparatively understudied. However, various local and regional studies and anecdotal observations indicate that western mussels are also declining, suggesting the need for range-wide assessments of extinction risk and changes in freshwater mussel distributions. Using historic (pre-1990) and recent (1990–2015) occurrence data from across western states and incorporating observations of recent population dynamics, we assessed the extinction risk of western freshwater mussels according to the categories and criteria of the International Union for Conservation of Nature (IUCN) Red List. Percent change in occupied watersheds (by area) between historic and recent time periods was evaluated against IUCN-established thresholds. Additionally, we considered whether evidence of declines was also supported by reported observations of changes in abundance or occurrence in studied water bodies, watersheds, or regions. We also assessed the proportion of watersheds that have reduced species richness as compared with historic levels. We evaluated four western freshwater mussel taxonomic entities: three currently recognized species and one clade consisting of two currently recognized species. Of the four entities assessed, two are Vulnerable (Anodonta nuttalliana and Gonidea angulata), one is Near Threatened (Margaritiferafalcata), and one is Least Concern (Anodonta oregonensis/kennerlyi clade). Freshwater mussel richness declined 35% across western watersheds by area, and among the most historically diverse watersheds, nearly half now support fewer species/clades. Future research and conservation efforts should prioritize identifying the proximate causes for these declines and preserving existing habitat and populations.

Geography, geology and ecology influence population genetic diversity and structure in the endangered endemic Azorean Ammi (Apiaceae)

Three Azorean endemic Ammi species were initially described: Ammi trifoliatum (Wats.) Trel., Ammi seubertianum (Wats.) Trel. and Ammi huntii (Wats.) Trel. Many taxonomic changes have been conducted, and one to three species have been considered. Two species are currently accepted: A. trifoliatum, which occurs in almost every island, and A. seubertianum, with a narrower distribution. In this research, the population genetic diversity and structure of the Azorean Ammi species were assessed using eight specifically designed SSR markers. A wide sampling of A. seubertianum and A. trifoliatum was conducted in seven Azorean islands, and four A. huntii herbarium samples were also included to further contribute to the taxonomy of this genus in Azores. Flores populations showed the highest genetic diversity, while North of Topo, in Sao Jorge, showed the lowest. None of the populations analysed displayed signs of putative inbreeding. The population genetic structure analyses conducted partially provided support for the two currently accepted species, but other possible cryptic taxa may also be present. The complex clustering obtained seems to result from a combined action of geography, geology and ecology, and although island-specific genetic patterns were found, environmental conditions connected to different altitudes and the existence of micro-niches may also play an important role. A thorough morphological revision and ecophysiological studies should be conducted to clarify the number of endemic taxonomic entities present in the Azores archipelago.

Unexpected mosaic distribution of two hybridizing sibling lineages in the teleplanically dispersing snail Stramonita haemastoma suggests unusual postglacial redistribution or cryptic invasion.

Molecular approaches have proven efficient to identify cryptic lineages within single taxonomic entities. Sometimes these cryptic lineages maybe previously unreported or unknown invasive taxa. The genetic structure of the marine gastropod Stramonita haemastoma has been examined in the Western Mediterranean and North‐Eastern Atlantic populations with mtDNA COI sequences and three newly developed microsatellite markers. We identified two cryptic lineages, differentially fixed for alternative mtDNA COI haplogroups and significantly differentiated at microsatellite loci. The mosaic distribution of the two lineages is unusual for a warm‐temperate marine invertebrate with a teleplanic larval stage. The Atlantic lineage was unexpectedly observed as a patch enclosed in the north of the Western Mediterranean Sea between eastern Spain and the French Riviera, and the Mediterranean lineage was found in Macronesian Islands. Although cyto‐nuclear disequilibrium is globally maintained, asymmetric introgression occurs in the Spanish region where the two lineages co‐occur in a hybrid zone. A first interpretation of our results is mito‐nuclear discordance in a stable postglacial hybrid zone. Under this hypothesis, though, the location of genetic discontinuities would be unusual among planktonic dispersers. An alternative interpretation is that the Atlantic lineage, also found in Senegal and Venezuela, has been introduced by human activities in the Mediterranean area and is introgressing Mediterranean genes during its propagation, as theoretically expected. This second hypothesis would add an additional example to the growing list of cryptic marine invasions revealed by molecular studies.