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Campanula L. is among the genera with the highest number of endemics in the Caucasus ecoregion. A group of attractive alpine and subalpine perennial rosette plants with short single-flowered stems centred in the Caucasus has been treated as Campanula subg. Scapiflorae or at other ranks, with considerably varying circumscription and classification. Molecular phylogenetic analysis of three plastid DNA regions (trnK/matK, petD, rpl16) of a strongly extended sampling, comprising 23 of the 27 commonly accepted taxa (85%) with 330 accessions built on and guided by the results of our previous study of the group, confirmed the polyphyly of C. subg. Scapiflorae in any of its circumscriptions. The core clade of the group comprises exclusively endemics and near-endemics of the Caucasus and is treated here as C. sect. Tridentatae in a revised circumscription. The phylogenetic relationships of the disparate other elements of the Scapiflorae group are outlined.

A taxonomic backbone of the Plumbaginaceae is presented and the current state of knowledge on phylogenetic relationships and taxon limits is reviewed as a basis for the accepted taxon concepts. In total, 4,476 scientific names and designations are treated of which 30 are not in the family Plumbaginaceae. The Plumbaginaceae are subdivided in three tribes with 26 genera and 1,179 accepted species. Two subgenera, 17 sections, two subsections and 187 infraspecific taxa are accepted. At the species and infraspecific level 2,782 synonyms were assigned to accepted taxa, whereas 194 names were excluded from the core checklist (i.e., unplaced taxa, infrageneric subdivisions with still uncertain application, names of verified uncertain application, invalid horticultural names, excluded names from other families, other excluded designations, and unresolved names). The EDIT Platform for Cybertaxonomy was utilized as the tool to compile and manage the names and further taxonomic data under explicit taxon concepts. Secundum references are given in case taxon concepts were taken from the literature, whereas this study serves as reference for newly circumscribed taxa. The family’s division into the tribes Aegialitideae, Limonieae, and Plumbagineae departs from earlier two-subfamily classifications, prompted by recent phylogenetic findings that challenge the subfamilial affinity of Aegialitis. The genus Acantholimon was extended to include Gladiolimon, as currently available phylogenetic and morphological data support this merger. In Limonium, all accepted species could be assigned to sections and subsections or the “Mediterranean lineage”, respectively, making use of the phylogenetic distribution of their morphological characters and states. A new combination and/or status is proposed for Dyerophytum socotranum, Limonium thymoides, Limonium × fraternum, Limonium × rossmaessleri, and Limonium sect. Jovibarba. Special attention is given to nomenclatural issues, particularly for Statice nomen ambiguum to resolve the names under accepted names. The use of artificial groupings like “aggregates”, “complexes” and “species groups” in alpha-taxonomic treatments is discussed. The taxonomic backbone will receive continued updates and through the Caryophyllales Taxonomic Expert Network, it contributes the treatment of the Plumbaginaceae for the World Flora Online.

The Gynoxyoid clade of the Senecioneae (Asteraceae) until now included the five genera Aequatorium, Gynoxys, Nordenstamia, Paracalia and Paragynoxys as diagnosed using selected morphological characters. In their pre-phylogenetic circumscription, the genera Aequatorium and Paragynoxys were considered to inhabit the northern Andes in contrast to Nordenstamia and Paracalia that occur in the central Andes. The most species-rich genus, Gynoxys, was believed to be distributed throughout the Andes. We use a recently established plastid phylogenomic framework that rendered Gynoxys paraphyletic to further evaluate the delimitation of genera in the Gynoxyoid clade. We examine the morphological variation of all members of the Gynoxyoid to identify characters potentially informative at genus level. This results in a matrix of eleven, mostly multistate characters, including those originally used to diagnose these genera. The ancestral character state inference displays a high level of homoplasy, but nevertheless supports the recognition of four genera. Aequatorium is characterised by white radiate capitula. Paracalia and Paragynoxys share white flowers and floral characteristics, such as flower opening and length of disc flowers lobes, as plesiomorphic states, but differ in habit (scandent shrubs vs. trees). Paracalia also retained white flowers, but its two species are characterised by the absence of outer phyllaries. The genera Gynoxys and Nordenstamia comprise species with yellow capitula which appear to be a derived feature in the Gynoxyoids. The genus Nordenstamia, with eight species, is synonymised under Gynoxys since molecular evidence shows its species nested within various parts of the Gynoxys subclade and the morphological variation of Nordenstamia falls well within that of Gynoxys. With the goal to assign all species to four genera (Aequatorium, Gynoxys, Paracalia and Paragynoxys), we assess the states for the eleven characters for all members of the Gynoxyoids and generate new ETS and ITS sequences for 171 specimens belonging to 49 species to further support their generic placement. We provide a taxonomic treatment for the four genera recognised here including amended diagnoses and morphological descriptions. Furthermore, a species-level taxonomic backbone is elaborated for all genera using electronic tools that list 158 currently accepted names and synonyms (209 names in total) with the respective protologue and type information, as well as notes on the current understanding of species limits. Eleven names are newly synonymised, two are lectotypified and eight are newly transferred to other genera.

Abstract DNA barcoding aids in rapidly identifying specimens in various contexts by comparing short stretches of DNA to a reference database. Barcoding initiatives generate large reference databases of carefully curated high‐quality sequences to maximize identification success. BarKeeper provides a flexible tool for barcoding initiatives and in the context of phylogenetic studies to foster shared work on large datasets of raw sequence and associated metadata. It is free, open‐source and available as a set of Docker containers for easy setup. After setting it up once, all project members can use it independently of their operating system or location. BarKeeper offers features to collect and manage data and metadata about specimens, taxa and DNA sequences from Sanger sequencing and high‐throughput sequencing (HTS) technologies. It provides excellent flexibility by not being restricted to specific markers or taxon groups. Users can view and edit records and associated metadata while the app assists them by trimming and assembling reads. It automatically checks the quality of generated barcodes with a taxonomy‐based tool and offers a wide range of options for data analysis. Extensive search features allow querying the database for specific groups of records and saving the search results in the user's profile or downloading them in various file formats. BarKeeper combines multiple tools to aid barcoding projects in every step, from a reference taxa list to finished barcode sequences, thereby minimizing the number of laborious, potentially error‐prone manual steps and enabling efficient collaborative workflows.

In this study, we present an overall phylogenetic framework for Dianthus using four plastid regions (matK-trnK-psbA, rpl32-trnL, trnQ-rps16) and nuclear ITS and a species-level checklist for the genus developed by using all available databases and the literature. The trees from the plastid dataset depict a clade of Dianthus that also includes Velezia and a few taxa of Petrorhagia. New combinations in Dianthus are provided for these species. The checklist of Dianthus in this new delimitation covers 1781 names, with 384 accepted species, 150 subspecies, 12 heterotypic varieties and two forms (not counting autonyms), 1050 synonyms, 22 hybrid names and 172 unresolved names, 3 names were excluded. Implications for the evolution of flower characters, life forms, biogeography, as well as sectional classification are discussed based on the phylogenetic framework.

VIETBIO [Innovative approaches to biodiversity discovery and characterisation in Vietnam] is a bilateral German-Vietnamese research and capacity building project focusing on the development and transfer of new methods and technology towards an integrated biodiversity discovery and monitoring system for Vietnam. Dedicated field training and testing of innovative methodologies were undertaken in Cuc Phuong National Park as part and with support of the project, which led to the new biodiversity data and records made available in this article collection.VIETBIO is a collaboration between the Museum für Naturkunde Berlin – Leibniz Institute for Evolution and Biodiversity Science (MfN), the Botanic Garden and Botanical Museum, Freie Universität Berlin (BGBM) and the Vietnam National Museum of Nature (VNMN), the Institute of Ecology and Biological Resources (IEBR), the Southern Institute of Ecology (SIE), as well as the Institute of Tropical Biology (ITB); all Vietnamese institutions belong to the Vietnam Academy of Science and Technology (VAST).The article collection "VIETBIO" (https://doi.org/10.3897/bdj.coll.63) reports original results of recent biodiversity recording and survey work undertaken in Cuc Phuong National Park, northern Vietnam, under the framework of the VIETBIO project. The collection consist of this “main” cover paper – characterising the study area, the general project approaches and activities, while also giving an extensive overview on previous studies from this area – followed by individual papers for higher taxa as studied during the project. The main purpose is to make primary biodiversity records openly available, including several new and interesting findings for this biodiversity-rich conservation area. All individual data papers with their respective primary records are expected to provide useful baselines for further taxonomic, phylogenetic, ecological and conservation-related studies on the respective taxa and, thus, will be maintained as separate datasets, including separate GUIDs also for further updating.

Most plastid genome sequences are assembled from short-read whole-genome sequencing data, yet the impact that sequencing coverage and the choice of assembly software can have on the accuracy of the resulting assemblies is poorly understood. In this study, we test the impact of both factors on plastid genome assembly in the threatened and rare endemic shrub Calligonum bakuense. We aim to characterize the differences across plastid genome assemblies generated by different assembly software tools and levels of sequencing coverage and to determine if these differences are large enough to affect the phylogenetic position inferred for C. bakuense compared to congeners. Four assembly software tools (FastPlast, GetOrganelle, IOGA, and NOVOPlasty) and seven levels of sequencing coverage across the plastid genome (original sequencing depth, 2,000x, 1,000x, 500x, 250x, 100x, and 50x) are compared in our analyses. The resulting assemblies are evaluated with regard to reproducibility, contig number, gene complement, inverted repeat length, and computation time; the impact of sequence differences on phylogenetic reconstruction is assessed. Our results show that software choice can have a considerable impact on the accuracy and reproducibility of plastid genome assembly and that GetOrganelle produces the most consistent assemblies for C. bakuense. Moreover, we demonstrate that a sequencing coverage between 500x and 100x can reduce both the sequence variability across assembly contigs and computation time. When comparing the most reliable plastid genome assemblies of C. bakuense, a sequence difference in only three nucleotide positions is detected, which is less than the difference potentially introduced through software choice.

Abstract High Andean forests harbor a remarkably high biodiversity and play a key role in providing vital ecosystem services for neighboring cities and settlements. However, they are among the most fragmented and threatened ecosystems in the neotropics. To preserve their unique biodiversity, a deeper understanding of the effects of anthropogenic perturbations on them is urgently needed. Here, we characterized the plant communities of high Andean forest remnants in the hinterland of Bogotá in 32 0.04 ha plots. We assessed the woody vegetation and sampled the understory and epiphytic cover. We gathered data on compositional and structural parameters and compiled a broad array of variables related to anthropogenic disturbance, ranging from local to landscape‐wide metrics. We also assessed phylogenetic diversity and functional diversity. We employed nonmetric multidimensional scaling (NMDS) to select meaningful variables in a first step of the analysis. Then, we performed partial redundancy analysis (pRDA) and generalized linear models (GLMs) in order to test how selected environmental and anthropogenic variables are affecting the composition, diversity, and aboveground biomass of these forests. Identified woody vegetation and understory layer communities were characterized by differences in elevation, temperature, and relative humidity, but were also related to different levels of human influence. We found that the increase of human‐related disturbance resulted in less phylogenetic diversity and in the phylogenetic clustering of the woody vegetation and in lower aboveground biomass (AGB) values. As to the understory, disturbance was associated with a higher diversity, jointly with a higher phylogenetic dispersion. The most relevant disturbance predictors identified here were as follows: edge effect, proximity of cattle, minimum fragment age, and median patch size. Interestingly, AGB was efficiently predicted by the proportion of late successional species. We therefore recommend the use of AGB and abundance of late successional species as indicators of human disturbance on high Andean forests.

Plants, fungi and algae are important components of global biodiversity and are fundamental to all ecosystems. They are the basis for human well-being, providing food, materials and medicines. Specimens of all three groups of organisms are accommodated in herbaria, where they are commonly referred to as botanical specimens.The large number of specimens in herbaria provides an ample, permanent and continuously improving knowledge base on these organisms and an indispensable source for the analysis of the distribution of species in space and time critical for current and future research relating to global biodiversity. In order to make full use of this resource, a research infrastructure has to be built that grants comprehensive and free access to the information in herbaria and botanical collections in general. This can be achieved through digitization of the botanical objects and associated data.The botanical research community can count on a long-standing tradition of collaboration among institutions and individuals. It agreed on data standards and standard services even before the advent of computerization and information networking, an example being the Index Herbariorum as a global registry of herbaria helping towards the unique identification of specimens cited in the literature.In the spirit of this collaborative history, 51 representatives from 30 institutions advocate to start the digitization of botanical collections with the overall wall-to-wall digitization of the flat objects stored in German herbaria. Germany has 70 herbaria holding almost 23 million specimens according to a national survey carried out in 2019. 87% of these specimens are not yet digitized. Experiences from other countries like France, the Netherlands, Finland, the US and Australia show that herbaria can be comprehensively and cost-efficiently digitized in a relatively short time due to established workflows and protocols for the high-throughput digitization of flat objects.Most of the herbaria are part of a university (34), fewer belong to municipal museums (10) or state museums (8), six herbaria belong to institutions also supported by federal funds such as Leibniz institutes, and four belong to non-governmental organizations. A common data infrastructure must therefore integrate different kinds of institutions.Making full use of the data gained by digitization requires the set-up of a digital infrastructure for storage, archiving, content indexing and networking as well as standardized access for the scientific use of digital objects. A standards-based portfolio of technical components has already been developed and successfully tested by the Biodiversity Informatics Community over the last two decades, comprising among others access protocols, collection databases, portals, tools for semantic enrichment and annotation, international networking, storage and archiving in accordance with international standards. This was achieved through the funding by national and international programs and initiatives, which also paved the road for the German contribution to the Global Biodiversity Information Facility (GBIF).Herbaria constitute a large part of the German botanical collections that also comprise living collections in botanical gardens and seed banks, DNA- and tissue samples, specimens preserved in fluids or on microscope slides and more. Once the herbaria are digitized, these resources can be integrated, adding to the value of the overall research infrastructure. The community has agreed on tasks that are shared between the herbaria, as the German GBIF model already successfully demonstrates.We have compiled nine scientific use cases of immediate societal relevance for an integrated infrastructure of botanical collections. They address accelerated biodiversity discovery and research, biomonitoring and conservation planning, biodiversity modelling, the generation of trait information, automated image recognition by artificial intelligence, automated pathogen detection, contextualization by interlinking objects, enabling provenance research, as well as education, outreach and citizen science.We propose to start this initiative now in order to valorize German botanical collections as a vital part of a worldwide biodiversity data pool.

We present a first study of the diversity and community composition of lichens in seasonally dry tropical forest (DTF) remnants in the Atlántico department, Colombia. Lichens were sampled in two of the three protected areas of the department: Distrito de Manejo Integrado (DMI) Luriza and Reserva Forestal Protectora (RFP) El Palomar. The inventory revealed 61 species, including four new to science: Fissurina linoana Lücking, Moncada & G. Rodr. sp. nov., Graphis lurizana Lücking, Moncada & Celis sp. nov., G. mokanarum Lücking, Moncada & M.C. Martínez sp. nov., and Phaeographis galeanoae Lücking, Moncada & B. Salgado-N. sp. nov. Arthonia erupta and Coenogonium saepincola are new to South America, whereas thirteen species are recorded for Colombia for the first time. Further 37 species are new records for Atlántico, raising the total of species known from the department from 27 to 84. With 42 species at Luriza and 31 at El Palomar, species richness was comparable to that of other DTF sites in the Neotropics. Overlap in species composition between the two sites was remarkably low, with only twelve shared species (20 %), indicating a high level of heterogeneity. Biogeographical affinities lie with Central American DTF, which is in line with those of woody plants. These results underline the importance of the remaining fragments of DTF in Colombia in conserving partially unknown biodiversity and the necessity for their continuing conservation.

The sequencing and comparison of plastid genomes are becoming a standard method in plant genomics, and many researchers are using this approach to infer plant phylogenetic relationships. Due to the widespread availability of next-generation sequencing, plastid genome sequences are being generated at breakneck pace. This trend towards massive sequencing of plastid genomes highlights the need for standardized bioinformatic workflows. In particular, documentation and dissemination of the details of genome assembly, annotation, alignment and phylogenetic tree inference are needed, as these processes are highly sensitive to the choice of software and the precise settings used. Here, we present the procedure and results of sequencing, assembling, annotating and quality-checking of three complete plastid genomes of the aquatic plant genus Cabomba as well as subsequent gene alignment and phylogenetic tree inference. We accompany our findings by a detailed description of the bioinformatic workflow employed. Importantly, we share a total of eleven software scripts for each of these bioinformatic processes, enabling other researchers to evaluate and replicate our analyses step by step. The results of our analyses illustrate that the plastid genomes of Cabomba are highly conserved in both structure and gene content.

The Campanuloideae (Campanulaceae) are a highly diverse clade of angiosperms found mostly in the Northern Hemisphere, with the highest diversity in temperate areas of the Old World. Chloroplast markers have greatly improved our understanding of this clade but many relationships remain unclear primarily due to low levels of molecular evolution and recent and rapid divergence. Furthermore, focusing solely on maternally inherited markers such as those from the chloroplast genome may obscure processes such as hybridization. In this study we explore the phylogenetic utility of two low-copy nuclear loci from the pentatricopeptide repeat gene family (PPR). Rapidly evolving nuclear loci may provide increased phylogenetic resolution in clades containing recently diverged or closely related taxa. We present results based on both chloroplast and low-copy nuclear loci and discuss the utility of such markers to resolve evolutionary relationships and infer hybridization events within the Campanuloideae clade.The inclusion of low-copy nuclear genes into the analyses provides increased phylogenetic resolution in two species-rich clades containing recently diverged taxa. We also obtain support for the placement of two early diverging lineages (Jasione and Musschia-Gadellia clades) that have previously been unresolved. Furthermore, phylogenetic analyses of PPR loci revealed potential hybridization events for a number of taxa (e.g., Campanula pelviformis and Legousia species). These loci offer greater overall topological support than obtained with plastid DNA alone.This study represents the first inclusion of low-copy nuclear genes for phylogenetic reconstruction in Campanuloideae. The two PPR loci were easy to sequence, required no cloning, and the sequence alignments were straightforward across the entire Campanuloideae clade. Although potentially complicated by incomplete lineage sorting, these markers proved useful for understanding the processes of reticulate evolution and resolving relationships at a wide range of phylogenetic levels. Our results stress the importance of including multiple, independent loci in phylogenetic analyses.

Plastid genomes exhibit different levels of variability in their sequences, depending on the respective kinds of genomic regions. Genes are usually more conserved while noncoding introns and spacers evolve at a faster pace. While a set of about thirty maximum variable noncoding genomic regions has been suggested to provide universally promising phylogenetic markers throughout angiosperms, applications often require several regions to be sequenced for many individuals. Our project aims to illuminate evolutionary relationships and species-limits in the genus Pyrus (Rosaceae)-a typical case with very low genetic distances between taxa. In this study, we have sequenced the plastid genome of Pyrus spinosa and aligned it to the already available P. pyrifolia sequence. The overall p-distance of the two Pyrus genomes was 0.00145. The intergenic spacers between ndhC-trnV, trnR-atpA, ndhF-rpl32, psbM-trnD, and trnQ-rps16 were the most variable regions, also comprising the highest total numbers of substitutions, indels and inversions (potentially informative characters). Our comparative analysis of further plastid genome pairs with similar low p-distances from Oenothera (representing another rosid), Olea (asterids) and Cymbidium (monocots) showed in each case a different ranking of genomic regions in terms of variability and potentially informative characters. Only two intergenic spacers (ndhF-rpl32 and trnK-rps16) were consistently found among the 30 top-ranked regions. We have mapped the occurrence of substitutions and microstructural mutations in the four genome pairs. High AT content in specific sequence elements seems to foster frequent mutations. We conclude that the variability among the fastest evolving plastid genomic regions is lineage-specific and thus cannot be precisely predicted across angiosperms. The often lineage-specific occurrence of stem-loop elements in the sequences of introns and spacers also governs lineage-specific mutations. Sequencing whole plastid genomes to find markers for evolutionary analyses is therefore particularly useful when overall genetic distances are low.

BACKGROUND: Speciose clades usually harbor species with a broad spectrum of adaptive strategies and complex distribution patterns, and thus constitute ideal systems to disentangle biotic and abiotic causes underlying species diversification. The delimitation of such study systems to test evolutionary hypotheses is difficult because they often rely on artificial genus concepts as starting points. One of the most prominent examples is the bellflower genus Campanula with some 420 species, but up to 600 species when including all lineages to which Campanula is paraphyletic. We generated a large alignment of petD group II intron sequences to include more than 70% of described species as a reference. By comparison with partial data sets we could then assess the impact of selective taxon sampling strategies on phylogenetic reconstruction and subsequent evolutionary conclusions. METHODOLOGY/PRINCIPAL FINDINGS: Phylogenetic analyses based on maximum parsimony (PAUP, PRAP), Bayesian inference (MrBayes), and maximum likelihood (RAxML) were first carried out on the large reference data set (D680). Parameters including tree topology, branch support, and age estimates, were then compared to those obtained from smaller data sets resulting from "classification-guided" (D088) and "phylogeny-guided sampling" (D101). Analyses of D088 failed to fully recover the phylogenetic diversity in Campanula, whereas D101 inferred significantly different branch support and age estimates. CONCLUSIONS/SIGNIFICANCE: A short genomic region with high phylogenetic utility allowed us to easily generate a comprehensive phylogenetic framework for the speciose Campanula clade. Our approach recovered 17 well-supported and circumscribed sub-lineages. Knowing these will be instrumental for developing more specific evolutionary hypotheses and guide future research, we highlight the predictive value of a mass taxon-sampling strategy as a first essential step towards illuminating the detailed evolutionary history of diverse clades.

Premise of the study: The current study aimed at developing nuclear microsatellite markers for the relict tree species , which is threatened in its natural range in the South Caucasus. Methods and Results: Pyrosequencing of an enriched microsatellite library on the Roche FLX platform using the 454 Titanium kit produced 86,058 sequence reads, most of which contained short tandem repeats. Eighty microsatellite loci identified using the software package QDD version 1 were selected and tested for proper PCR amplification. Of these, 13 allowed proper amplification and were shown to be polymorphic among a sample of 25 Z. carpinifolia specimens from various geographic origins. Conclusions: The set of microsatellite markers will be suitable for the assessment of genetic diversity in Z. carpinifolia. They will allow for an examination of phylogeographic patterns as well as of population structure and gene flow within this species.

Biosynthesis of the hypericins that accumulate in the dark glands of some members of the genus Hypericumis poorly understood. The gene named hyp-1, isolated from Hypericum perforatumL. has been proposed as playing an important role in the final steps of hypericin biosynthesis. To study the role of this candidate gene in relation to the production of hypericins, the expression of this gene was studied in 15 Hypericumspecies with varying ability to synthesise hypericin. While the accumulation of hypericins and emodin, an intermediate in the respective pathway, was associated with the dark glands in the hypericin-producing species, the hyp-1gene was expressed in all studied species regardless of whether hypericins and emodin were detected in the plants. The coding sequences of hyp-1cDNA were isolated from all species and showed more than 86% similarity to each other. Although, in general, an increased level of the hyp-1gene transcript was detected in hypericin-producing species, several of the hypericin-lacking species expressed comparable levels as well. Our results question the role of the hyp-1gene product as a key enzyme responsible for biosynthesis of hypericins in the genus Hypericum. The function of the hyp-1gene may not be restricted to hypericin biosynthesis only, or some additional factors are necessary for completion of hypericin biosynthesis. [ABSTRACT FROM AUTHOR]

This study represents the first comprehensive analysis of phylogenetic relationships within the Australian water-lilies, Nymphaeasubg. Anecphya. Our 51-accession dataset covers all 10 species of the subgenus, except the newly described N. alexii, and includes information from the nuclear ITS as well as from the chloroplast trnT–trnFregion. The results show that molecular data are consistent with morphology, because the subdivision of subg. Anecphyainto two major clades, a large-seeded and a small-seeded group, could be confirmed. Within the large-seeded group, Nymphaea atransand N. immutabilisseem to form one clade, whereas samples of N. gigantea, N. georginae, N. macrospermaand N. carpentariaeform another. Relationships within the small-seeded group, containing all samples of N. violacea, N. elleniaeand N. hastifolia, are less clear, since the trees obtained from the chloroplast and the nuclear marker are incongruent. The samples of N. violaceado not form a monophyletic group in each of the trees, but—at least in the ITS tree—group with either N. elleniaeor N. hastifolia/Ondinea, respectively. Polymorphisms among ITS paralogues, i.e. substitutions at single nucleotide positions and length polymorphisms, have been observed in some samples of N. violacea.This fact as well as the incongruent phylogenetic signal obtained from the chloroplast and the nuclear genomes point to recent hybridisation or introgression in this group. Remarkably, Ondinea purpureais resolved within the small-seeded group by both markers and seems to have a close relationship to N. hastifolia.Although incomplete lineage sorting cannot be fully excluded to explain high variability in N. violacea, molecular data potentially hint to a case of still imperfect taxonomy. [ABSTRACT FROM AUTHOR]

Necrotizing fasciitis (NF) is a rare mono-/polymicrobial skin infection that spreads to underlying tissues. NF is quickly progressing and leads to life threatening situations. Immediate surgical debridement together with i.v. antibiotic administration is required to avoid fatal outcome. Early diagnosis is often delayed due to underestimation or confusion with cellulitis. We now compared the initial clinical and laboratory presentation of NF and cellulitis in detail to assess if a typical pattern can be identified that aids timely diagnosis of NF and avoidance of fatal outcome. 138 different clinical and laboratory features of 29 NF patients were compared to those of 59 age- and gender matched patients with severe erysipelas requiring a subsequent hospitalization time of ≥10 days. Differences in clinical presentation were not obvious; however, NF patients suffered significantly more often from strong pain. NF patients exhibited dramatically elevated CRP levels (5-fold, p>0.001). The overall laboratory risk indicator for necrotizing fasciitis (LRINEC) score was significantly higher in NF patients as compared to cellulitis. However, a modification of the score (alteration of laboratory parameters, addition of clinical parameters) led to a clear improvement of the score with a higher positive predictive value without losing specificity. In summary, clinical differentiation of NF from cellulitis appears to be hard. 'Pain out of proportion' may be an early sign for NF. An improvement of the LRINEC score emphasizing only relevant laboratory and clinical findings as suggested may aid the early diagnosis of NF in the future leading to improvement of disease outcome by enabling rapid adequate therapy.