Diverse Genus Research Articles

Myxomycetes associated with the bark, cones and leaves of Australian cypress pines (Callitris spp.)

Context The diversity of myxomycetes associated with Australia’s most diverse native conifer genus, Callitris, has been incompletely studied.Aims In this study, we examine the diversity of myxomycetes associated with outer bark, fallen cones and dead litter (leaves/needles) of four Callitris species.Methods Substrate samples were collected from 13 localities in New South Wales, Queensland and the Northern Territory. Samples were used to prepare moist-chamber cultures, and species of associated myxomycetes were identified.Key results Twenty-three species in 15 genera were recorded. Percentage occurrence of myxomycetes varied depending on substrate, being 87% (cones), 83% (bark) and 63% (litter). Bark yielded the most species (17), followed by litter (10) and cones (6). Only two species (Arcyria cinerea and S. fusca) were recorded from all three substrates. Substrate pH is often an important factor for the occurrence of myxomycetes, but the mean values recorded for cones (5.7), litter (5.8), and bark (5.9) showed little difference. This suggests that other undetermined factors contributed to the differences in species occurrence. In addition to the records generated in the present study, we provide a list of previous records of myxomycetes found in association with Callitris.Conclusions This study has highlighted, for the first time, the diversity of myxomycetes associated with members of the genus Callitris and has shown the importance of cypress pines as a substrate for myxomycetes.Implications This study leads to a better understanding of the biogeography, distribution and ecology of myxomycetes and their associated organisms.

Taxonomy and biogeography of living species of the Family Notorotaliidae (Notorotalia, Parrellina, Porosorotalia, Buccella, Cristatavultus)

DNA sequencing shows that species of the genera Notorotalia, Porosorotalia and Buccella form a distinct branch (Notorotaliidae) of Rotaloidea, and cluster as sister to Elphidiidae. In this review we report on the sequencing of three species of Buccella (from the Arctic Ocean, Patagonia and Chile) and one each of Notorotalia (New Zealand) and Porosorotalia (Chile). This information has been combined with all the morphological descriptive information on species of these genera plus the genera Cristatavultus and Parrellina to provide a global synthesis of living species of the Notorotaliidae. We recognize 11 species of the southern hemisphere genus Notorotalia, which has a centre of diversity around New Zealand (8 species). A second southern-hemisphere-restricted genus, restricted to eastern Australia is Parrellina (3 species) although specimens (possibly introduced) have been recorded from the Mediterranean Sea. Cristatavultus has a single species, with a tropical west Pacific distribution.We synonymize Cribrorotalia under Porosorotalia, which has a disjunct distribution with one species in the northwest Pacific and a second around the southern parts of South America. Buccella is the most diverse and widespread genus (16 species recognized) with its greatest abundance in the Arctic Ocean and around subantarctic-temperate South America. Five species of Buccella live in a belt along the west coast of central America, from USA to Peru, with some spillage into the Caribbean Sea and Gulf of Mexico. Two new species of Buccella are recognized: B. dejardini (from South Georgia) and Buccella n. sp. A (from Chile).

Profiling of the intestinal community of Clostridia: taxonomy and evolutionary analysis.

Aim: Clostridia are relevant commensals of the human gut due to their major presence and correlations to the host. In this study, we investigated intestinal Clostridia of 51 healthy subjects and reconstructed their taxonomy and phylogeny. The relatively small number of intestinal Clostridia allowed a systematic whole genome approach based on average amino acid identity (AAI) and core genome with the aim of revising the current classification into genera and determining evolutionary relationships. Methods: 51 healthy subjects' metagenomes were retrieved from public databases. After the dataset's validation through comparison with Human Microbiome Project (HMP) samples, the metagenomes were profiled using MetaPhlAn3 to identify the population ascribed to the class Clostridia. Intestinal Clostridia genomes were retrieved and subjected to AAI analysis and core genome identification. Phylogeny investigation was conducted with RAxML and Unweighted Pair Group Method with Arithmetic Mean (UPGMA) algorithms, and SplitsTree for split decomposition. Results: 225 out of 406 bacterial taxonomic units were ascribed to Bacillota [Firmicutes], among which 124 were assigned to the class Clostridia. 77 out of the 124 taxonomic units were referred to a species, altogether covering 87.7% of Clostridia abundance. According to the lowest AAI genus boundary set at 55%, 15 putative genera encompassing more than one species (G1 to G15) were identified, while 19 species did not cluster with any other one and each appeared to belong to a diverse genus. Phylogenetic investigations highlighted that most of the species clustered into three main evolutive clades. Conclusion: This study shed light on the species of Clostridia colonizing the gut of healthy adults and pinpointed several gaps in knowledge regarding the taxonomy and the phylogeny of Clostridia.

Permian-Triassic insect diversity revealed by fossils from China

Most of the research on Paleoentomology focuses on describing morphology and classification of one species of fossil insects. However, there is little information on the temporal diversity of insects during the Permian and Triassic periods. The end-Permian mass extinction (EPME) was the greatest biological and ecological crisis of the Phanerozoic Eon on Earth, while the pattern of recovery of terrestrial ecosystem is still unclear. In this paper, the population and distribution of insects in various regions of China before and after the fifth mass extinction were studied by counting the fossil literature data of insects from the Permian to Triassic. We found the genus diversity of the proto-orthoptera decreased after the mass extinction. The Blattoidea (cockroach) showed a brief trend of extinction after the mass extinction, but soon returned to prosperity; Hemiptera’s population was less affected by mass extinctions, with only minor fluctuations in diversity and subsequent prosperity beyond the Permian; The order Mecoptera is speculated to be an emerging species of the Triassic. Specific trend changes for the above four purposes may be affected by volcanic activity. Insect diversification can reflect changes in terrestrial ecology, providing a reliable example of changes in our current climate environment: scientists can predict the possible ecological impact of global warming through previous records, and take preventive measures to prevent the mass extinction of species again.

The genus Platytyphlops (Cumacea: Crustacea): A new species from Argentina, taxonomic status of Platytyphlops orbicularis (Calman, 1905), and remarks on the genus

Platytyphlops uteae n. sp. is described based on a few specimens collected off the coast of Buenos Aires Province at 1011–1712 m depth during the surveys Atlantis II 60 (1971) and Talud Continental III (2013). In addition, Platytyphlops orbicularis, a species described by W. T. Calman in 1905 based on a single fragmentary specimen from West Ireland, is briefly redescribed. Furthermore, the specimens from the east coast of USA assigned to P. orbicularis by Calman in 1912, are herein considered to be conspecific with P. uteae n. sp. These two species are closely related. P. uteae n. sp. can be easily separated from P. orbicularis by: (1) the absence of submedian carinae on the carapace (present in P. orbicularis), (2) the female carapace being as wide as long (wider than long in P. orbicularis); and (3) the fifth pereopod as long as the fifth pereonite (much shorter than the fifth pereonite in P. orbicularis). Platytyphlops is a diverse genus that currently encompasses 24 species. Based on morphological data, three species groups within this genus are herein proposed. In addition, the bathymetrical range of all the species currently in Platytyphlops are updated and compared.

Vascular flora of dry scrub in Southern Ecuador

This study lists dry scrub species that grow in western lowlands and interandean valleys in south Ecuador. Using material from field trips spanning over two years, we were able to identify 314 species belonging to 71 families and 221 genera. The most diverse families are Asteraceae (33 sp.), Fabaceae s.l. (27 sp.) and Poaceae (19 sp.). The most diverse genera are Croton (8 sp.) Euphorbia (6 sp.), Oxalis (5 sp.) and Senna (5 sp.). 7.01% of the flora (22 sp.) is endemic to the study area, and 6.4% (20 sp.) is adventive. The dominant life form is hemycryptophyte with 85 species (27.1%). Epiphytes, with 6 species, are the life form with fewer species (1.9%). The work contributes to the knowledge about plant diversity that is highly noticeable in southern Ecuador.

The second European representative of the epallagid genus Labandeiraia in the lowermost Eocene Oise amber (Odonata, Zygoptera)

Among the calopteran damselflies, the family Epallagidae was clearly dominating the diversity of the Holarctic Cenozoic (11 described species in eight extinct genera), while the Calopterygidae were extremely rare at the same time (six Cenozoic species in two extant and one fossil genera) (Fossilworks database at http://www.fossilworks.org/cgi-bin/bridge.pl?action=home, consulted 21/10/2022). They mainly belonged to the extinct subfamily Eodichrominae Cockerell, 1923, and their most diverse genus was the early Eocene genus Labandeiraia Petrulevičius et al., 2007, known from compression fossils from the lacustrine Green River Formation (USA) and the marine Fur Formation in Denmark (Petrulevičius et al., 2007; Bechly et al., 2020).

Ecological distribution of modern diatom in peatlands in the northern Greater Khingan Mountains and its environmental implications.

Relationships between diatom assemblages and environmental variables in peatlands of the northern Greater Khingan Mountains are helpful for understanding the indicative significance of diatoms to environment changes, and potentially provide a reference for environmental monitoring and paleoenvironment reconstruction in the edge of monsoon region. In this study, we analyzed modern diatom assemblages and their relationships with environment factors in 30 surface samples from shrubby-herbaceous and herbaceous peatlands based on ordination analysis. Benthic and epiphytic Pennatae diatoms are mainly ecological types, whereas planktonic Centricae diatoms are relatively fewer. The most diverse genera are Pinnularia and Eunotia. Eunotia paludosa and Achnanthidium minutissimum dominated in shrubby-herbaceous peatlands, while Navicula minima and Fragilaria capucina dominated in herbaceous peatlands. The diatom community structures are different in different vegetation types and the diatom species diversity in herbaceous peatlands is higher than that in shrubby-herbaceous peatlands. CODMn and pH are the most important environmental factors affecting diatom species composition and diversity. Eunotia bilunaris, Eunotia mucophila, and Eunotia paludosa can be used as indicators of acidic water environments. Caloneis silicula, Fragilaria capucina, Hantzschia amphioxys, and Navicula radiosa can be applied to indicate the weak alkaline conditions. Eunotia bilunaris and Eunotia paludosa can indicate low conductivity, while Sellaphora pupula indicates the medium-high conductivity. Fragilaria capucina and Navicula radiosa can indicate oligotrophic habitats.

Comparative Genomic and Metagenomic Investigations of the Corynebacterium tuberculostearicum Species Complex Reveals Potential Mechanisms Underlying Associations To Skin Health and Disease.

Corynebacterium are a diverse genus and dominant member of the human skin microbiome. Recently, we reported that the most prevalent Corynebacterium species found on skin, including Corynebacterium tuberculostearicum and Corynebacterium kefirresidentii, comprise a narrow species complex despite the diversity of the genus. Here, we apply high-resolution phylogenomics and comparative genomics to describe the structure of the C. tuberculostearicum species complex and highlight genetic traits which are enriched or depleted in it relative to other Corynebacterium. Through metagenomic investigations, we also find that individual species within the complex can associate with specific body sites. Finally, we discover that one species from the complex, C. kefirresidentii, increases in relative abundance during atopic dermatitis flares, and show that most genomes of this species encode a colocalized set of putative virulence genes. IMPORTANCE Corynebacterium are commonly found bacteria on the human skin. In this study, we perform comparative genomics to gain insight into genetic traits which differentiate a phylogenetically related group of Corynebacterium, the Corynebacterium tuberculostearicum species complex, that includes the most prevalent species from the genus in skin microbiomes. After resolving the presence of distinct species within the complex, we applied metagenomic analysis to uncover biogeographic associations of individual species within the complex with specific body sites and discovered that one species, commonly found in the nares of individuals, increases in abundance across multiple body sites during atopic dermatitis flares.

Phylogeny and systematics of the tribe Sonerileae (Melastomataceae) in Africa: A revised taxonomic classification

AbstractThe tribe Sonerileae in tropical Africa and Madagascar is a morphologically diverse lineage that consists of 239 species in 10 genera. In this study, we present the first in‐depth phylogenetic analysis of African Sonerileae to test monophyly of the currently recognized genera. Phylogenetic analyses were performed using sequence data from two nuclear (nrITS and nrETS) and three plastid loci (accD‐psaI, ndhF and psbK‐psbL). Sampling consisted of 140 accessions including 64 African, 27 Malagasy, 46 Asian, and three neotropical Sonerileae together with a broad outgroup sampling (105 spp.). Phylogenetic relationships were inferred using maximum likelihood and Bayesian inference approaches, and a careful reassessment of morphological characters was carried out. Our results neither support the monophyly of the Old World nor African Sonerileae. The monospecific African genus Benna is partially supported as sister to Phainantha, one of the basal neotropical lineages, while African and Malagasy Medinilla are nested among the SE Asian genera. Gravesia (116 spp.), the most species‐rich and morphologically diverse genus in Madagascar, is recovered as monophyletic. The African genera of Sonerileae Calvoa, Dicellandra, and Preussiella form well‐supported clades. In contrast, Amphiblemma (including Amphiblemma molle) and Cincinnobotrys s.l. (including Cincinnobotrys felicis) are not monophyletic. To accommodate the caulescent C. felicis we propose reinstatement of the monospecific genus Bourdaria. For the distinctive A. molle a new genus Mendelia is described. Calvoa hirsuta is designated here as the type of genus Calvoa, lectotypes are designated for Medinilla engleri and Veprecella lutea, and a neotype is designated for Preussiella kamerunensis.

An early snapshot of plant-herbivore interactions: Psilophyton diakanthon sp. nov. from the Early Devonian of Gaspé (Quebec, Canada).

Trimerophytes are a plexus of early tracheophytes that form the base of the euphyllophyte clade and, thus, represent the link between the earliest land plants and modern-day ferns, sphenophytes, and seed plants. As the best-characterized trimerophyte, the genus Psilophyton occupies a key position in the euphyllophyte fossil record. We describe a new Psilophyton species that has implications for the evolution of plant-animal interactions. The fossil material is preserved by permineralization in the Lower Devonian (Emsian) Battery Point Formation (Québec, Canada) and was studied in serial sections using the cellulose acetate peel technique. Psilophyton diakanthon sp. nov. differs from other Psilophyton species in possessing fibers that form a discontinuous layer in the inner cortex and two distinct types of spinescent emergences whose anatomy and morphology are consistent with roles in anti-herbivore defense. Psilophyton diakanthon adds another species to an already diverse genus. Its two morphologically distinct types of spinescence suggest that herbivory was rampant in plant-animal interactions and demonstrate that anti-herbivory defenses had reached a previously unrecognized level of sophistication by 400 million years ago, in the Early Devonian.

Lactifluus hezhangensis sp. nov. (Russulaceae, Russulales) from Southwest China

Lactifluus is an ectomycorrhizal, genetically diverse genus which consists of many species complexes. The genus is widely distributed in the tropics and drives important ecological and economic functions. However, its generic relations are poorly known and the diversity is mostly unexplored. In this study, we propose a new species, Lactifluus hezhangensis sp. nov. belongs to Lf. sect. Gerardii, from Guizhou Province, China. Lactifluus hezhangensis is characterized by a rugose and dark brown pileus, pruinose near center; white to cream lamella, and small basidiospores (4.79) 5.06–7.22 (7.30) × (4.67) 4.68–6.20 (6.59) μm). The phylogenetic analyses based on combined three-gene fragments of ITS + LSU + RPB2 confirmed that the new species is distinct from other Lactifluus species. Furthermore, the new species is described with color photographs and compared with similar taxa. We provide a phylogeny for Lf. sect. Gerardii based on ITS, LSU + RPB2 sequence data and the taxonomic status of the new species is briefly discussed.

Variability of Reproduction Pathways in the Central-European Populations of Hawthorns with Emphasis on Triploids.

The role of apomeiosis, parthenogenesis, and pseudogamy in the asexual reproduction of some plant groups has not been fully elucidated in relation to species diversification. Quantitative analyses of seed origin may help in gaining better understanding of intercytotypic interactions. Asexual reproduction associated with polyploidy and frequent hybridization plays a crucial role in the evolutionary history of the genus Crataegus in North America. In Europe, the genus represents a taxonomically complex and very difficult species group not often studied using a modern biosystematic approach. We investigated the reproduction pathways in mixed-cytotype populations of selected taxa of Crataegus in eastern Slovakia, Central Europe. The investigated accessions were characterized by seed production data and the ploidy level of mature plants as well as the embryo and endosperm tissues of their seeds determined via flow cytometry. Diploid and polyploid hawthorns reproduce successfully; they also produce high numbers of seeds. An exception is represented by an almost sterile triploid. Diploids reproduce sexually. Polyploids shift to asexual reproduction, but pseudogamy seems to be essential for regular seed development. In rare cases, fertilization of unreduced gametes occurs, which offers opportunity for the establishment of new polyploid cytotypes between diploid sexuals and polyploid asexuals. Opposite to sexual diploids, triploids are obligate, and tetraploids almost obligate apomicts. Apomixis is considered to help stabilize individual weakly differentiated polyploid microspecies. Pseudogamy is a common feature and usually leads to unbalanced maternal to paternal contribution in the endosperm of triploid accessions. Parental contribution to endosperm gene dosage is somehow relaxed in triploids. Our Crataegus plant system resembles reproduction in the diploids and polyploids of North American hawthorns. Our data provide support for the hypothesis that polyploidization, shifts in reproduction modes, and hybridization shape the genus diversity also in Central Europe.

Chromosomal rearrangements and the first indication of an ♀X1 X1 X2 X2 /♂X1 X2 Y sex chromosome system in Rineloricaria fishes (Teleostei: Siluriformes).

Rineloricaria is the most diverse genus within the freshwater fish subfamily Loricariinae, and it is widely distributed in the Neotropical region. Despite limited cytogenetic data, records from southern and south-eastern Brazil suggest a high rate of chromosomal rearrangements in this genus, mirrored in remarkable inter- and intraspecific karyotype variability. In the present work, we investigated the karyotype features of Rineloricaria teffeana, an endemic representative from northern Brazil, using both conventional and molecular cytogenetic techniques. We revealed different diploid chromosome numbers (2n) between sexes (33♂/34♀), which suggests the presence of an ♀X1 X1 X2 X2 /♂X1 X2 Y multiple sex chromosome system. The male-limited Y chromosome was the largest and the only biarmed element in the karyotype, implying Y-autosome fusion as the most probable mechanism behind its origination. C-banding revealed low amounts of constitutive heterochromatin, mostly confined to the (peri)centromeric regions of most chromosomes (including the X2 and the Y) but also occupying the distal regions of a few chromosomal pairs. The chromosomal localization of the 18S ribosomal DNA (rDNA) clusters revealed a single site on chromosome pair 4, which was adjacent to the 5S rDNA cluster. Additional 5S rDNA loci were present on the autosome pair 8, X1 chromosome, and in the presumed fusion point on the Y chromosome. The probe for telomeric repeat motif (TTAGGG)n revealed signals of variable intensities at the ends of all chromosomes except for the Y chromosome, where no detectable signals were evidenced. Male-to-female comparative genomic hybridization revealed no sex-specific or sex-biased repetitive DNA accumulations, suggesting a presumably low level of neo-Y chromosome differentiation. We provide evidence that rDNA sites might have played a role in the formation of this putative multiple sex chromosome system and that chromosome fusions originate through different mechanisms among different Rineloricaria species.

Diversity and Ecology of Lobophora Species Associated with Coral Reef Systems in the Western Gulf of Thailand, including the Description of Two New Species

The brown macroalgal genus Lobophora plays important ecological roles in many marine ecosystems. This group has received much attention over the past decade, and a considerable number of new species have been identified globally. However, our knowledge of the genus diversity and ecology along south-east Asian coasts are still limited. Given the growing body of research that uses a combination of molecular and morphological data to identify cryptic species, this study investigates the diversity of Lobophora in the western Gulf of Thailand using morphological and molecular data, as well as their interactions with scleractinian corals. A total of 36 Lobophora specimens were collected from 15 sites in the western Gulf of Thailand and used for molecular and morphological analyses. One mitochondrial (cox3) and two chloroplast (psbA and rbcL) genes were amplified and sequenced for molecular phylogenetic analyses. Based primarily on phylogenetic evidence, two new species were formally described, L. chumphonensis sp. nov. and L. thailandensis sp. nov. Additionally, L. lamourouxii was newly recorded from Thailand. Two new lineages of Lobophora obscura were identified, L. obscura12 and L. obscura13. Among the Lobophora species identified, three were found in interaction with corals, the most notable of which was the massive coral Porites. Lobophora chumphonensis sp. nov. only interacted with Porites by growing on bare coral skeleton between Porites colonies. Furthermore, L. obscura13 was observed under the branching coral Pocillopora. Our findings revealed that Lobophora presented both effects and absence of effects on coral. A thorough understanding of Lobophora diversity and ecology is essential for ongoing and future research on coral-macroalgal ecological relationships.

Hohenbergia erecta (Bromeliaceae: Bromelioideae), a New Once-branched Species from Chapada Diamantina, Bahia State, Brazil

Hohenbergia is one the most diverse genera in Bahia state, and inhabits almost all regions of the state. As a result of ongoing studies on Hohenbergia in Bahia, Brazil, here we describe and illustrate Hohenbergia erecta, endemic to the municipality of Mucugê, at Chapada Diamantina. Hohenbergia erecta differs from its morphologically related, H. catingae, by an elongated tubular rosette (vs short stem with a crateriform rosette), and a once-branched cylindrical inflorescence (vs 2–3-branched pyramidal inflorescence), with branches congested at the apex (vs branches laxly arranged). Due to a small distribution area in the Caatinga forest and based on a spatial analysis we categorized it as Endangered (EN), following the IUCN criteria. Hohenbergia erecta is endemic to the central region of Chapada Diamantina, dominant in the area, where no other known Hohenbergia species have been found sympatrically. It is important, however, that new field expeditions are conducted in the region to observe the richness of the genus at Chapada Diamantina.

Will general antiviral protocols always be science fiction?

Currently, antiviral drugs are targeted at specific viruses, requiring extensive research to develop de novo before a trial molecule is approved for a single viral target. However, it is possible that a strategic asset for mainstreaming antivirals has been hiding in plain sight. In our recent article published in Frontiers in Pharmacology, we explored the scope for plant-derived polyphenols, such as flavonoids, to be applied against infections spanning phylogenetically unrelated virus families. Beyond a long history of safe use in ordinary diet, common polyphenols also feature promiscuous binding behavior, a quality echoed by laboratory evidence that many are effective in vitro against viruses from diverse genera. Moreover, we mapped the research base undergirding the inflammatory response’s tendency to selectively return serum polyphenols from their latent, metabolized form back into their active, promiscuously-binding form uniquely at sites of inflammation -- such as those routinely established by viral infections. Verifying efficacy of flavonoids to constitute an annually-updated general antiviral protocol will require mobilizing a spectrum of animal model studies and clinical trials for initial confirmation.

Quaternary coral, coralline algal and vermetid assemblages as sea-level indicators: a review

Corals, coralline algae and vermetid gastropods are indirect (marine limiting) relative sea-level (RSL) indicators. The precision in sea-level reconstruction based on fossils of those organisms depends on the probable palaeodepth in which they grew. Constraining such palaeodepth depends, in turn, on the available information about the habitats of their living counterparts. Diverse genera, species and species assemblages of corals, coralline algae and vermetid gastropods have historically been proposed as reliable indicators of narrow, shallow depth ranges. However, the increased information on depth distribution of marine benthos in the last two decades has challenged some early assumptions about depth ranges of taxa considered diagnostic of precise palaeodepths. Here, the authors test the reliability of coral, coralline algal and vermetid assemblages that have been extensively used in RSL reconstructions in the light of data from Ocean Biogeographical Information System (OBIS) and other recently published data. In the Indo-Pacific province, these data support the use of the robust-branching and the shallow, high-energy encrusting coral assemblages with a 0 to 10 m uncertainty. In both cases many component species have unimodal distributions and both median and average water depths are shallower than 10 m. The reliability of these coral assemblages as indicative of shallow water depths is strengthened when corals are encrusted by thick plants of the coralline alga Porolithon gr. onkodes. According to OBIS data, coralline algae of this species group in the Indo-Pacific are restricted to very shallow waters (95% probability of occurrence shallower than 0.2 m and in 99.6% of records shallower than 6 m). However, such a narrow depth range and the overall scarce data on coralline algal species in the OBIS database are questionable due to difficulties of coralline algal species identification with the naked eye. A comprehensive survey of the modern distribution of coralline algae at One Tree Reef (southern Great Barrier Reef) indicates that P. gr. onkodes has a log-normal distribution with median depth of less than 5 m and 95% of occurrence probability of thick crusts (> 0.2 mm) shallower than 8.8 m. Data on modern distribution of vermetids are scarce. In the OBIS database, vermetid species are reported from relatively wide depth ranges. However, relatively high densities (> 10 individuals per m2) on coral and coralline algal surfaces only occur from above mean low tide to some 6 m depth. In the Western Atlantic-Caribbean province Acropora palmata is the most precise RSL marker and no additional components of fossil assemblages improve its palaeodepth information. The confident use of coralgal and vermetid assemblages as RSL indicators relies on the identification of fossil corals and coralline algae at the species or species-group level. The scarcity of available data highlights the need for further studies on distribution of coralline algal species and vermetid in modern coral reefs from a variety of oceans and reef settings.

Editorial

Shakespeare’s interest in ancient Rome spans the whole of his dramatic career, from Titus Andronicus to Cymbeline, while Roman history and Latin culture permeate the whole of his work, well beyond the explicitly ‘Roman’ plays and poems. Critical interest has to some extent shifted from the historicist Roman plays based on Plutarch, Julius Caesar and Antony and Cleopatra, and the pseudo-historical Coriolanus, to the outlying Roman plays that evidence greater generic diversity and stylistic innovation, the early Senecan tragedy Titus Andronicus and the late ‘British’ romance Cymbeline. In these latter plays, the complex interactions between past and present, that are the main subject of the formal histories, are presented with even more aesthetic flexibility and creative improvisation than the ‘Roman plays’ proper.

Does phenotyping of Hypericum secondary metabolism reveal a tolerance to biotic/abiotic stressors?

In this review we summarize the current knowledge about the changes in Hypericum secondary metabolism induced by biotic/abiotic stressors. It is known that the extreme environmental conditions activate signaling pathways leading to triggering of enzymatic and non-enzymatic defense systems, which stimulate production of secondary metabolites with antioxidant and protective effects. Due to several groups of bioactive compounds including naphthodianthrones, acylphloroglucinols, flavonoids, and phenylpropanes, the world-wide Hypericum perforatum represents a high-value medicinal crop of Hypericum genus, which belongs to the most diverse genera within flowering plants. The summary of the up-to-date knowledge reveals a relationship between the level of defense-related phenolic compounds and interspecific differences in the stress tolerance. The chlorogenic acid, and flavonoids, namely the amentoflavone, quercetin or kaempferol glycosides have been reported as the most defense-related metabolites associated with plant tolerance against stressful environment including temperature, light, and drought, in association with the biotic stimuli resulting from plant-microbe interactions. As an example, the species-specific cold-induced phenolics profiles of 10 Hypericum representatives of different provenances cultured in vitro are illustrated in the case-study. Principal component analysis revealed a relationship between the level of defense-related phenolic compounds and interspecific differences in the stress tolerance indicating a link between the provenance of Hypericum species and inherent mechanisms of cold tolerance. The underlying metabolome alterations along with the changes in the activities of ROS-scavenging enzymes, and non-enzymatic physiological markers are discussed. Given these data it can be anticipated that some Hypericum species native to divergent habitats, with interesting high-value secondary metabolite composition and predicted high tolerance to biotic/abiotic stresses would attract the attention as valuable sources of bioactive compounds for many medicinal purposes.