Pogostemon jaitapurensis (Lamiaceae), a new species from India based on morphological and molecular evidence

Based on morphological and molecular analyses, Pogostemon jaitapurensis is described and illustrated as a new species from Konkan region of Maharashtra, India. Present study added the molecular data of Indian endemic Pogostemon species of sect. Verticillatus and provide their phylogenetic placement. The bayesian and parsimony phylogenetic analyses conducted resolve Pogostemon into two clades, from them the new species belongs to Clade B and shows close relationship with species of sect. Verticillatus. A possible relationship between the new species and P. deccanensis and P. erectus, endemic to India, is also revealed by the phylogenetic analyses. Phylogenetically, the new species has been also placed in genus Pogostemon subg. Dysophyllus sect. Verticillatus. Sectional classification of these species is congruent with their phylogenetic positions.

The Genus Plagiothecium Schimp. (Plagiotheciaceae, Bryophyta) in Eurasia: An Annotated Checklist with Distribution and Ecological Data

An annotated checklist of the pleurocarpous moss genus Plagiothecium in Eurasia is presented for the first time based on a thorough review of the literature. Data have been compiled from previous relevant works conducted on the genus over more than 70 years and published up to the end of June 2020 for 107 Eurasian countries (and islands). Sectional classification is based on molecular phylogeny of the genus published recently. A total of 41 taxa are reported, including 29 species and 12 infraspecific taxa (nine varieties and three forms) belonging to eight sections. The highest numbers of taxa were found in China (20 taxa), the Russian Federation (20 taxa) and Japan (18 taxa), while the smallest numbers of taxa were recorded in the Middle East, Central Asia and the islands area. Not a single species of Plagiothecium was recorded in 26 regions, whereas P. denticulatum, P. nemorale and P. cavifolium turned out to be the most widespread species in the entire study area. They were recorded in most of the surveyed countries and islands. For each accepted taxon, information on relevant literature, synonyms, distribution within Eurasia and globally are provided. Comments on each taxon, ecological preferences, and notes on doubtful records are also included. Additionally, distribution maps for each recognised taxon are supplied. This checklist can enlighten and foster a better understanding of the distribution, diversity, and ecology of Plagiothecium in Eurasia and provides an incentive for future research on the genus.

Taxonomic Revisiting and Phylogenetic Placement of Two Endangered Plant Species: Silene leucophylla Boiss. and Silene schimperiana Boiss. (Caryophyllaceae)

The genus Silene L. is one of the largest genera in Caryophyllaceae, and is distributed in the Northern Hemisphere and South America. The endemic species Silene leucophylla and the near-endemic S. schimperiana are native to the Sinai Peninsula, Egypt. They have reduced population size and are endangered on national and international scales. These two species have typically been disregarded in most studies of the genus Silene. This research integrates the Scanning Electron Microscope (SEM), species micromorphology, and the phylogenetic analysis of four DNA markers: ITS, matK, rbcL and psb-A/trn-H. Trichomes were observed on the stem of Silene leucophylla, while the S. schimperiana has a glabrous stem. Irregular epicuticle platelets with sinuate margin were found in S. schimperiana. Oblong, bone-shaped, and irregularly arranged epidermal cells were present on the leaf of S. leucophylla, while Silene schimperiana leaf has “tetra-, penta-, hexa-, and polygonal” epidermal cells. Silene leucophylla and S. schimperiana have amphistomatic stomata. The Bayesian phylogenetic analysis of each marker individually or in combination represented the first phylogenetic study to reveal the generic and sectional classification of S. leucophylla and S. schimperiana. Two Silene complexes are proposed based on morphological and phylogenetic data. The Leucophylla complex was allied to section Siphonomorpha and the Schimperiana complex was related to section Sclerocalycinae. However, these two complexes need further investigation and more exhaustive sampling to infer their complex phylogenetic relationships.

TAXONOMIC REVIEW AND PHYLOGENETIC INVESTIGATIONS OF LAVANDULA FROM IRAN AND OMAN

A review of the native Iranian species of Lavandula is presented, including the first recorded occurrence of L. pubescens, new distribution records for L. coronopifolia, and a detailed description and observations of the poorly known endemic L. sublepidota. The phylogenetic relationships of several taxa, including Lavandula sublepidota and L. hasikensis from Oman, are investigated for the first time using molecular data (matK and ITS regions), and changes to the sectional classification are proposed.

A taxonomic revision of the genus Sorbaria (Rosaceae) with a new infrageneric classification based on morphology, micromorphology, and palynology

In the present study, we presented a taxonomic revision of the genus Sorbaria (Sorbarieae; Amygdaloideae) with a new infrageneric classification. Moreover, we extensively reviewed various data for Sorbaria species, including previous anatomical, micromorphological, and palynological data. The new sectional classification was based on morphological, micromorphological, and palynological evidence, with two sections: sect. Sorbaria aut. and sect. Kirilowiana J.-H. Song & S.-P. Hong (sect. nov.). Overall, four species and five varieties (including two nomenclatural novelties) were recognized: S. sorbifolia (Linnaeus) A. Braun var. sorbifolia, S. sorbifolia var. glandulifolia J.-H. Song & S.-P. Hong, S. sorbifolia var. stellipila Maximowicz, S. pallasii (G. Don) Pojarkova, S. tomentosa (Lindley) Rehder var. tomentosa, S. tomentosa var. angustifolia (Wenzig) Rahn., S. kirilowii (Regel & Tiling) Maximowicz var. kirilowii, S. kirilowii var. arborea (C.K. Schneider) J.-H. Song & S.-P. Hong (comb. & stat. nov.), and S. kirilowii var. dubia (C.K. Schneider) J.-H. Song & S.-P. Hong (comb. nov.). Some illustrations and syntype were designated as the lectotype for several names. The classification was based on a comprehensive morphological examination of herbarium specimens, including field observations and observations of types, micromorphological, and palynological characteristics. In addition, we provided an identification key, diagnostic characteristics, full descriptions, comprehensive nomenclatural treatments and taxonomic notes (including complete synonymy), and distribution maps of Sorbaria species.

A Toxic Story: Phylogeny and Classification of Strychnos L. (Loganiaceae)

Strychnos is a pantropical genus of Loganiaceae (Gentianales), with approximately 200 species, that lacks a detailed worldwide phylogenetic understanding until now. We investigated the global phylogeny of the majority of Strychnos species, and evaluated morphologicaland key character patterns to discuss congruence between phylogenetic clades and sectional classification systems. We included 147 ITS sequences across 12 genera, with 127 samples (103 species) of Strychnos and 20 outgroup accessions (19 species) in a Bayesian analysis. Tribes Antonieae, Loganieae, and Spigelieae were supported as monophyletic, but Strychneae was resolved as polyphyletic due to the positioning of Gardneria placed outside of the Strychnos + Neuburgia clade. Strychnos was supported as strongly monophyletic with 12 strongly supported clades, but the relationships among many of these clades were not well resolved. Most of the 12 sections in the current infrageneric classification system of Strychnos were resolved as non-monophyletic, indicating the need for a revision of the sectional divisions. Characters common in species placed within the relatively more nested clades include a non-climbing habit, invasion of non-rainforest habitats, absence of tendrils,absence of secondary phloem, and elongated corolla tubes, suggesting that these characters are relatively derived conditions in the genus. Inflorescence position, fruit size, and fruit wall thickness are extremely variable and were distributed among various clades in our phylogeny. Stamen, pistil, seed and seed coat, and phytochemical characters have figured prominently in the taxonomy of the genus, but are as yet incompletely described, thus preventing significant inference about their evolution. Most of the 12 well-supported clades within Strychnos are restricted to specific continents, sometimes with limited dispersion between neighboring continents, suggesting a history of repeated cross-oceanic dispersal or vicariance patterns. The Neotropical clades nested within the African clades have the shortest branches and themost unresolved topologies, probably indicating relatively recent radiation in the Neotropics.

Paraphyly of the genus Boehmeria (Urticaceae): a response to Liang et al. ‘Relationships among Chinese Boehmeria species and the evolution of various clade’

Boehmeria, as currently circumscribed, comprises 52 species and has a pantropical distribution. Liang et al. propose a sectional classification of Boehmeria based on the phylogenetic analysis of SNP data for 20 species and an additional 10 subspecific taxa of these at the rank of variety or form. They restrict their sampling to species documented in China. We found many shortcomings in the sampling and analyses which we feel have resulted in a misleading phylogeny for the genus and the economically important fibre-plant, Boehmeria nivea. By sampling only Chinese species of this genus for their in-group and using a single distantly related outgroup, Liang et al. have failed to capture the diversity of the genus and so erroneously concluded that it forms a monophyletic group. Previous published research clearly demonstrates that Boehmeria is paraphyletic and polyphyletic, comprising at least four monophyletic groupings most closely related to several genera within the Boehmerieae. For these reasons, the sections that Liang et al. (Ind Crops Prod 148:112092, 2020. https://doi.org/10.1016/j.indcrop.2020.112092) propose for Boehmeria are not effective tools for its classification. The important fibre-plant, Boehmeria nivea, should therefore not be considered as part of the genus Boehmeria for the purposes of crop breeding, but as sister to Archiboehmeria. Breeding programmes for ramie should therefore focus on populations and germplasm of Archiboehmeria atrata. We conclude that poor taxon sampling, overlooking relevant molecular and taxonomic literature, internal conflict within their SNP data and the overinterpretation of low support values has resulted in the erroneous conclusion that Boehmeria represents a monophyletic or ‘natural’ genus.

Mericarp morphology of the genus Origanum (Lamiaceae) and its taxonomic significance in Turkey

Origanum is a well-known genus that is widely distributed and comprises many hybrids and endemic species in Turkey. Some morphological and molecular studies in the literature have aimed to clarify infrageneric or sectional classification of the genus. However, studies regarding the shape, size, and color of mericarps of Origanum taxa remain limited. The mericarp micromorphology of 30 taxa, including 7 hybrids of the genus Origanum, were evaluated herein using both stereo microscopy and scanning electron microscopy (SEM) to determine some useful features for taxonomical classification of the genus. The shapes of mericarps are usually ellipsoid, rarely ellipsoid-oblong, obovoid, broadly obovoid, while the color of mericarps vary from shades of brown to reddish. A significant variation was observed in the surface ornamentation of mericarps, which was mainly useful at the sectional and species level. Also determined were 2 main types: I and II, and 5 subtypes: pusticulate, reticulate-ruminate, reticulate-foveate, ruminate, and foveate. The micromorphological characters of mericarps, in addition to their morphological features, will contribute taxonomically to the classification of the sections of the genus Origanum and separation of the species within the sections. In addition, these characters will be useful to understand the effect of hybridization on variations in the micromorphological characters. This was the first detailed study on the mericarp micromorphology of the genus Origanum and its taxonomic implications.

Cystolith micromorphology in selected taxa of Ficus L. (Moraceae) in India and its taxonomic implications

Cystoliths are microscopic calcium deposits found remarkably in some genera and is of key importance to understand its taxonomic value. Leaf samples of 19 species belonging to 7 sections of Indian Ficus were processed for anatomical studies and surface micromorphological characteristics of cystoliths. The morphology, distribution and sculpture patterns of cystolith found varying among species. Four types of basic sculpturing patterns have been observed in this study: aculeate, colliculate, verrucate, and tuberculate. The aculeate sculpturing pattern is the most common type observed in twelve species of section Cordifoliae, but further division of this pattern into three subtypes i.e. broad, moderate and reduced aculeate along with the length and width of cystoliths appendages and the mode of stalk fixation provides more informative insight into sub-sectional classification. Principal component analysis (PCA) provides a supporting evidence for earlier classification at sectional/subsectional level. Though in few cases it has not support the decision taken by molecular studies. This study suggests that cystolith micromorphological characters could be utilized in the re-classification of Ficus taxa at sub-sectional level.