scholarly journals Deep phylogeographic splits but no taxonomic structure in the disjointly distributed Draba pacheri (Brassicaceae), a subendemic of the Eastern Alps

2021 ◽  
Author(s):  
Erich Kucs ◽  
Peter Schönswetter ◽  
Gerald M. Schneeweiss

AbstractDraba (Brassicaeae), a model group for diversification and evolution in Arctic and mountain habitats, is taxonomically challenging and many of its species are insufficiently investigated. One such species is D. pacheri, an endemic of the eastern European Alps and the western Carpathians (here presumably extinct). Several hypotheses exist with respect to the phylogenetic position and the taxonomy of this species, but none of these has ever been tested using molecular data. In this article we examine (i) DNA sequence data to assess the phylogenetic position of D. pacheri within the genus and (ii) AFLP fingerprint data as well as morphometric data to address whether this species can be divided taxonomically into species or subspecies. DNA sequence data firmly place D. pacheri within the Core Draba Group III, whose internal relationships are, however, insufficiently resolved to precisely identify the closest relative of D. pacheri. AFLP data identify several genetically divergent lineages corresponding to geographically distinct regions. Although these lineages are congruent with hypotheses distinguishing either two species (D. pacheri s. str., D. norica) or one species with several subspecies, the lack of clear morphological separation, both with respect to the entire set of traits and single presumably diagnostic characters such as trichome morphology, renders recognition of a single species D. pacheri, as suggested previously, the best taxonomic solution. The deep and geographically strongly structured splits of D. pacheri likely are the result of isolation in several Pleistocene refugia and warrant that conservation efforts should involve populations from each of the main geographic subgroups.

2018 ◽  
Vol 32 (6) ◽  
pp. 1316 ◽  
Author(s):  
Jahnavi Joshi ◽  
Gregory D. Edgecombe

Integrative taxonomy assesses the congruence between different lines of evidence for delimiting species, such as morphological, molecular or ecological data. Herein molecular phylogenetics is used to test monophyly and determine the phylogenetic position of the Old World tropical centipede genus Ethmostigmus Pocock, 1898, and to define species boundaries for Ethmostigmus in peninsular India. A phylogeny of the family Scolopendridae based on DNA sequence data for three markers from 427 specimens sampling in all major lineages (144 individuals generated in this study) recovers Ethmostigmus as a monophyletic group, but relationships among the genera in its subfamily Otostigminae are poorly supported. Two species delimitation methods for DNA sequence data and phylogeny are integrated with morphology and geographic data to propose a well-supported species hypothesis for Ethmostigmus on the peninsular Indian plate. Five species of Ethmostigmus are recognised in peninsular India, of which E. coonooranus Chamberlin, 1920 and three new species, namely, E. agasthyamalaiensis, sp. nov., E. sahyadrensis, sp. nov. and E. praveeni, sp. nov., occur in the Western Ghats, a biodiversity hotspot. The lesser-known Eastern Ghats harbour one species, E. tristis (Meinert, 1886), which has been nearly unreported for 130 years. This study highlights the value of an integrative approach to systematics, especially in underexplored, high biodiversity regions and where morphological variation is limited among closely related species.


2021 ◽  
Vol 12 ◽  
Author(s):  
Ying Zhang ◽  
Yupei Zhou ◽  
Wei Sun ◽  
Lili Zhao ◽  
D. Pavlic-Zupanc ◽  
...  

The genus Botryosphaeria includes more than 200 epithets, but only the type species, Botryosphaeria dothidea and a dozen or more other species have been identified based on DNA sequence data. The taxonomic status of the other species remains unconfirmed because they lack either morphological information or DNA sequence data. In this study, types or authentic specimens of 16 “Botryosphaeria” species are reassessed to clarify their identity and phylogenetic position. nuDNA sequences of four regions, ITS, LSU, tef1-α and tub2, are analyzed and considered in combination with morphological characteristics. Based on the multigene phylogeny and morphological characters, Botryosphaeria cruenta and Botryosphaeria hamamelidis are transferred to Neofusicoccum. The generic status of Botryosphaeria aterrima and Botryosphaeria mirabile is confirmed in Botryosphaeria. Botryosphaeria berengeriana var. weigeliae and B. berengeriana var. acerina are treated synonyms of B. dothidea. Botryosphaeria mucosa is transferred to Neodeightonia as Neodeightonia mucosa, and Botryosphaeria ferruginea to Nothophoma as Nothophoma ferruginea. Botryosphaeria foliicola is reduced to synonymy with Phyllachorella micheliae. Botryosphaeria abuensis, Botryosphaeria aesculi, Botryosphaeria dasylirii, and Botryosphaeria wisteriae are tentatively kept in Botryosphaeria sensu stricto until further phylogenetic analysis is carried out on verified specimens. The ordinal status of Botryosphaeria apocyni, Botryosphaeria gaubae, and Botryosphaeria smilacinina cannot be determined, and tentatively accommodate these species in Dothideomycetes incertae sedis. The study demonstrates the significance of a polyphasic approach in characterizing type specimens, including the importance of using of DNA sequence data.


2009 ◽  
Vol 34 (3) ◽  
pp. 595-601 ◽  
Author(s):  
Božo Frajman ◽  
Gerald M. Schneeweiss

The Balkan Peninsula is one of the few biodiversity hotspots in Europe, characterized by numerous endemic taxa. Due to their often-restricted distribution and the scarcity of modern phylogenetic and phylogeographic studies from this region, the phylogenetic position and taxonomy of these species are often poorly understood. One example is Asyneuma comosiforme, a stenoendemic species known only from the Shija Gorge in northeastern Albania. Since its description in 1921, the position of this poorly known species within Asyneuma has been questioned. Here, we use nuclear ITS and plastid trnL–trnF DNA sequence data to address the question of the phylogenetic position of this enigmatic species. The inferred phylogenies clearly support A. comosiforme as sister to the main clade of isophyllous Campanula species, which is supported by morphological and ecological similarities. Thus, a new nomenclatural combination, Campanula comosiformis, is proposed. Given the restricted distribution, this species should be considered at least vulnerable, but the small population size might warrant its classification as endangered.


2021 ◽  
Vol 12 ◽  
Author(s):  
Hong-Bo Jiang ◽  
Rajesh Jeewon ◽  
Samantha C. Karunarathna ◽  
Chayanard Phukhamsakda ◽  
Mingkwan Doilom ◽  
...  

Immotthia is a poorly known genus, and currently, no DNA sequence data are available to ascertain its proper phylogenetic placement and evolutionary relationships with other bitunicate fungi. To date, there are only two species accepted in the genus. During our ongoing research study of bambusicolous fungi in southwest China and Thailand, a fungus associated with stromata of Hypoxylon sp. was found on dead bamboo culms in Loei Province, Thailand. Preliminary morphological identification revealed that the fungal collection belongs to Immotthia. A novel species, Immotthia bambusae, is introduced herein based on a comparison of morphological characteristics with the type specimen of I. hypoxylon (≡ Amphisphaeria hypoxylon Ellis and Everh.), a synonym of I. atrograna (Cooke and Ellis) M. E. Barr. Phylogenetic analyses of a concatenated ITS, LSU, SSU, and TEF1-α DNA sequence matrix showed that Immotthia belongs to Dictyosporiaceae, Pleosporales. Despite I. bambusae strains constituting a supported subclade, they are nested with the genus Pseudocoleophoma. Pseudocoleophoma clematidis is morphologically different from all other Pseudocoleophoma species, while its conidial characteristics are similar to Cyclothyriella. Multigene phylogenetic analyses showed that P. clematidis formed a clade basal to Immotthia, separated from Pseudocoleophoma with strong statistical support. Therefore, we introduce a monotypic genus, Pseudocyclothyriella Phukhams. and Phookamsak, gen. nov. to accommodate the single species, Pseudocyclothyriella clematidis (Phukhams. and K. D. Hyde) Phukhams. and Phookamsak, comb. nov. Detailed descriptions, color micrographs, and phylogenetic trees to show the placement of the new taxa are provided. In addition, an updated taxonomic treatment of the genera Immotthia and Pseudocyclothyriella is also provided based on the study of the type materials and phylogeny generated from DNA sequence data.


Author(s):  
Thomas Stach ◽  
Samuel Dupont ◽  
Olle Israelson ◽  
Geraldine Fauville ◽  
Hiroaki Nakano ◽  
...  

The phylogenetic position of Xenoturbella spp. has been uncertain since their discovery in 1949. It has been recently suggested that they could be related to Ambulacraria within Deuterostomia. Ambulacraria is a taxon that has been suggested to consist of Hemichordata and Echinodermata. The hypothesis that X. bocki was related to Ambulacraria as well as the hypothesis of a monophyletic Ambulacraria is primarily based on the analysis of DNA sequence data. We tested both phylogenetic hypotheses using antibodies raised against SALMFamide 1 and 2 (S1, S2), neuropeptides isolated from echinoderms, on X. bocki and the enteropneust Harrimania kupfferi. Both species showed distinct positive immunoreactivity against S1 and S2. This finding supports the Ambulacraria-hypothesis and suggests a close phylogenetic relationship of X. bocki to Ambulacraria. In particular, the presence of immunoreactivity against S2 can be interpreted as a synapomorphy of Enteropneusta, Echinodermata, and Xenoturbella spp.


Botany ◽  
2012 ◽  
Vol 90 (6) ◽  
pp. 465-471 ◽  
Author(s):  
W.L. Bruckart ◽  
F.M. Eskandari ◽  
D.K. Berner ◽  
M.C. Aime

A rust disease caused by Puccinia acroptili P. Syd. & Syd. occurs throughout the range of Russian knapweed (Rhaponticum (syn. Acroptilon) repens), including North America. Differences in teliospore dimensions had been observed previously, but not quantified, between a specimen of P. acroptili from Turkey and one from the United States of America (USA). Similar differences were found during a recent evaluation of P. acroptili for biological control of R. repens in the USA; e.g., teliospores from eight USA isolates were 2.4 µm shorter (P = 0.05) than four isolates from Eurasia (two from Turkey, and one each from Russia and Kazakhstan). This inspired the generation of additional biological and DNA sequence data to clarify the significance of these differences between USA and Eurasian isolates. Although the USA isolates were found to have shorter teliospores, as noted in the description by Savile, teliospores of the USA isolates were also significantly wider in diameter than isolates from Eurasia; the latter in contrast to Savile’s observation. Biologically, the isolates were the same; all were equally aggressive in causing disease under common greenhouse test conditions, and fertile crosses occurred between isolates regardless of source. DNA sequence analyses of the nuclear rDNA large subunit and internal transcribed spacer regions supported the notion that P. acroptili is a single species, but it also revealed that small levels of variation may exist within the species. For these reasons, it has been concluded that USA and Eurasian accessions can be considered a single species, i.e., P. acroptili. Also, Savile’s observation about differences in spore dimensions is substantiated.


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