species circumscription
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Plants ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 1980
Author(s):  
Ji-Young Yang ◽  
Mi-Jung Choi ◽  
Seon-Hee Kim ◽  
Hyeok-Jae Choi ◽  
Seung-Chul Kim

The genus Hosta, which has a native distribution in temperate East Asia and a number of species ranging from 23 to 40, represents a taxonomically important and ornamentally popular plant. Despite its taxonomic and horticultural importance, the genus Hosta has remained taxonomically challenging owing to insufficient diagnostic features, continuous morphological variation, and the process of hybridization and introgression, making species circumscription and phylogenetic inference difficult. In this study, we sequenced 11 accessions of Hosta plastomes, including members of three geographically defined subgenera, Hosta, Bryocles, and Giboshi, determined the characteristics of plastomes, and inferred their phylogenetic relationships. We found highly conserved plastomes among the three subgenera, identified several mutation hotspots that can be used as barcodes, and revealed the patterns of codon usage bias and RNA editing sites. Five positively selected plastome genes (rbcL, rpoB, rpoC2, rpl16, and rpl20) were identified. Phylogenetic analysis suggested (1) the earliest divergence of subg. Hosta, (2) non-monophyly of subg. Bryocles and its two sections (Lamellatae and Stoloniferae), (3) a sister relationship between H. sieboldiana (subg. Giboshi) and H. ventricosa (subg. Bryocles), and (4) reciprocally monophyletic and divergent lineages of H. capitata in Korea and Japan, requiring further studies of their taxonomic distinction.


Zootaxa ◽  
2020 ◽  
Vol 4897 (1) ◽  
pp. 1-97
Author(s):  
ANDERSON LEPECO ◽  
RODRIGO BARBOSA GONÇALVES

Even after more than 250 years of taxonomic research on bees, there are still many gaps in the knowledge about their identity, classification and distribution patterns. Regarding the New World tribe Augochlorini, many efforts have been made in the last years to describe and organize its diversity. Within the tribe, Augochlora Smith has the widest distribution range, as these bees occur from Argentina to Southern Canada, including Caribbean islands. The genus comprises 124 described species in two extant subgenera, and, to date, two partial revisions are available, accounting for central Argentina and Uruguay and for northeastern Brazil. In the present study we review the Augochlora species occurring in Argentina, Paraguay, Uruguay and the southern Brazilian states of Paraná, Rio Grande do Sul, and Santa Catarina. Specimens from other Brazilian states and South American countries were also examined to help with species circumscription. We found 27 species in the studied area, including nine new species (Augochlora atlantica sp. nov., A. australis sp. nov., A. genalis sp. nov., A. helena sp. nov., A. hestia sp. nov., A. hirsuta sp. nov., A. laevicarinata sp. nov., A. mendax sp. nov., and A. scabrata sp. nov.) and the remaining redescribed when necessary. A key for the species occurring in the studied area is provided. Five new synonymies are proposed and the lectotypes of Augochlora francisca and Halictus esox are presently designated. The geographic distribution of most studied species is associated with the Atlantic biome in many ways. 


Flora ◽  
2020 ◽  
Vol 271 ◽  
pp. 151660
Author(s):  
Aline De Bastiani ◽  
Michelle Helena Nervo ◽  
Rodrigo B. Singer ◽  
Cristiano Roberto Buzatto

2020 ◽  
Vol 52 (3) ◽  
pp. 197-211 ◽  
Author(s):  
Scott LaGreca ◽  
H. Thorsten Lumbsch ◽  
Martin Kukwa ◽  
Xinli Wei ◽  
Jeong Eun Han ◽  
...  

AbstractLichens of the Ramalina siliquosa complex dominate seashore cliffs in Europe and South-East Asia, but their taxonomy has been vigorously debated for over a century. On many cliffs, they exhibit a bewildering zonation of chemotypes that resembles the classic zonation of organisms that occupy the littoral zone below. Do the chemotypes represent separate species, or infraspecific variation? To better understand the systematics of this group, sequences from four genetic loci (ITS, IGS, RPB1 and RPB2) were obtained for 59 samples from Denmark, France, Iceland, Norway, UK, Japan and Korea, including all major chemotypes. Maximum likelihood analysis of these sequences, together with sequences from 36 other Ramalina species, reveals that the complex comprises two distinct phylogenetic lineages, each including multiple chemotypes. These two putative species-level lineages correspond to the currently accepted taxa R. cuspidata and R. siliquosa. There is no evidence that these two taxa are phylogenetic sister species. Consequently, the explanation of this chemotype complex as an example of ‘sibling speciation’ is rejected. Specimens traditionally called ‘R. siliquosa’ from South-East Asia form a third clade, identified here as R. semicuspidata, with an additional, divaricatic acid chemotype. Other results include a robustly supported clade of Ramalina species that produce medullary depsides and depsidones; this clade includes another well-supported clade of south-eastern United States coastal plain and tropical Ramalina species. By contrast, large, strap-shaped Ramalina species that lack medullary depsides and depsidones occur in separate lineages. In addition, close relationships between the following groups of species are indicated: R. farinacea with R. subfarinacea; R. fraxinea with R. leptocarpha, R. menziesii and R. subleptocarpha; R. sinensis with R. unifolia. Furthermore, a new, variolaric acid-only chemotype is reported for R. farinacea, and a new, acid-deficient chemotype is reported for a more broadly circumscribed R. culbersoniorum.


Phytotaxa ◽  
2019 ◽  
Vol 403 (2) ◽  
pp. 122
Author(s):  
ALEJANDRO TORRES-MONTÚFAR ◽  
HELGA OCHOTERENA

Rovaeanthus (Rondeletieae, Rubiaceae) is a Mesoamerican endemic genus of two species, characterized by a fleshy, pubescent ring at the corolla mouth. Despite the molecular evidence, which suggested that Rovaeanthus shares a most recent common ancestor with the rest of the tribe Rondeletieae, it was treated as a synonym of Rogiera (Guettardeae), with which it shares the pubescent ring at the corolla mouth. Although the species circumscription of Rovaeanthus is clear, its recognition as a separate genus is not yet widely accepted. An updated identification key for the two species of Rovaeanthus, descriptions, distribution maps, phenological data, conservation status, and illustrations are provided.


2019 ◽  
Vol 152 (1) ◽  
pp. 53-67 ◽  
Author(s):  
Luiz Menini Neto ◽  
Cássio Van den Berg ◽  
Rafaela Campostrini Forzza

Background and aims – Pseudolaelia is a genus endemic to eastern Brazil, with 12 accepted species predominantly distributed across granitic inselbergs of the Brazilian Atlantic Forest. The aim of the present study was to distinguish between the very similar taxa P. aguadocensis, P. oliveirana, P. regentii and P. vellozicola, using morphometric data acquired as linear measurements and outlines capture with Elliptic Fourier Analysis (EFA) of the floral parts. Material and methods – We sampled 208 specimens from 11 natural populations of the above taxa. We measured 20 floral variables and for the EFA, and we extracted 24 shape variables from the Fourier coefficient matrices, which describe the outlines of the floral parts. In both cases the data were analyzed with multivariate methods (both ordination and clustering). Key results – We could not find morphological discontinuities with sufficient magnitude to consider P. aguadocensis, P. oliveirana and P. regentii as distinct species from P. vellozicola. Conclusions – We propose that P. vellozicola should be considered a polymorphic and widely distributed species, generally supported by both methods.


Phytotaxa ◽  
2018 ◽  
Vol 371 (2) ◽  
pp. 93
Author(s):  
ALIREZA POURSAFAR ◽  
YOUBERT GHOSTA ◽  
MOHAMMAD JAVAN-NIKKHAH

Stemphylium amaranthi was originally described from the leaves of Amaranthus retroflexous in China based only on asexual morphological characteristics. New collections of S. amaranthi from wheat and barley plants with symptoms of black (sooty) head mould in Golestan and Qazvin Provinces, Iran, revealed abundant formation of a sexual morph. The morphological identification was confirmed by sequences obtained from ITS-rDNA and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) genomic loci. New information on the sexual morph of S. amaranthi is provided and the species circumscription is emended. Wheat and barley are reported as new substrates for S. amaranthi, and this species is recorded for the first time in Iran.


Phytotaxa ◽  
2018 ◽  
Vol 367 (2) ◽  
pp. 101 ◽  
Author(s):  
ATENA ESLAMI FAROUJI ◽  
HAMED KHODAYARI ◽  
MOSTAFA ASSADI ◽  
BARIŞ ÖZÜDOĞRU ◽  
ÖZLEM ÇETIN ◽  
...  

Taxonomic descriptions of Iranian and Turkish Hesperis (Brassicaceae) species are generally insufficient and partly incomplete, which makes the species delimitation ambiguous. In order to clarify species circumscription, we scored 57 morphological descriptors (MDs) in 121 operational taxonomic units (OTUs) of Hesperis from Iran and Turkey and performed a multivariate analysis. The dendrogram was created from Gower’s distance matrix using Unweighted Pair Group Method with arithmetic mean (UPGMA) algorithm. The dendrogram clearly separates the 121 OTUs of Hesperis into five main phenons, which significantly deviate from the classical taxonomic treatment (sectional assignments) of the genus. Similar distinct delineation among the five phenons was revealed by a Principal Coordinate Analysis (PCoA), highlighting the resolving power of the multivariate analyses of quantitative and qualitative morphological characters. While there were significant variations among the OTUs for 57 MDs, the most distinctive morphological descriptors delimiting the phenons were estimated to be fruit, petal, stem, and leaf by a de-trended correspondence analysis (DCA). We also present a comparative discussion between the classical taxonomy and the delimitation of taxa revealed in our study.


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