scholarly journals Molecular phylogeny and species delimitation of the freshwater prawn Macrobrachium pilimanus species group, with descriptions of three new species from Thailand

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e10137
Author(s):  
Warut Siriwut ◽  
Ekgachai Jeratthitikul ◽  
Somsak Panha ◽  
Ratmanee Chanabun ◽  
Chirasak Sutcharit
Keyword(s):  
Genetic Diversity ◽  
Species Delimitation ◽  
Phylogenetic Analyses ◽  
Species Group ◽  
Freshwater Prawn ◽  
Species List ◽  
High Genetic Diversity ◽  
Widespread Species ◽  
Molecular Phylogenetic ◽  
Montane Streams

Specific status and species boundaries of several freshwater prawns in the Macrobrachium pilimanus species group remain ambiguous, despite the taxonomic re-description of type materials and additional specimens collected to expand the boundaries of some species. In this study, the “pilimanus” species group of Macrobrachium sensu Johnson (1958) was studied using specimens collected from montane streams of Thailand. Molecular phylogenetic analyses based on sequences of three molecular markers (COI, 16S and 18S rRNA) were performed. The phylogenetic results agreed with morphological identifications, and indicated the presence of at least nine putative taxa. Of these, six morphospecies were recognised as M. malayanum, M. forcipatum, M. dienbienphuense, M. hirsutimanus, M. eriocheirum, and M. sirindhorn. Furthermore, three morphologically and genetically distinct linages were detected, and are described herein as M. naiyanetri Siriwut sp. nov., M. palmopilosum Siriwut sp. nov. and M. puberimanus Siriwut sp. nov. The taxonomic comparison indicated wide morphological variation in several species and suggested additional diagnostic characters that are suitable for use in species diagnoses, such as the shape and orientation of fingers, the rostrum form, and the presence or absence of velvet pubescence hairs and tuberculated spinulation on each telopodite of the second pereiopods. The “pilimanus” species group was portrayed as non-monophyletic in both ML and BI analyses. The genetic structure of different geographical populations in Thailand was detected in some widespread species. The species delimitation based on the four delimitation methods (BIN, ABGD, PTP and GMYC) suggested high genetic diversity of the “pilimanus” species group and placed the candidate members much higher than in previous designations based on traditional morphology. This finding suggests that further investigation of morphological and genetic diversity of Southeast Asian freshwater prawns in the genus Macrobrachium is still required to provide a comprehensive species list to guide efforts in conservation and resource management.

Lifeforms as criterion for species delimitation: Are Aristida adscensionis and A. coerulescens (Aristidoideae, Poaceae) two species?

Phytotaxa ◽  
2019 ◽  
Vol 393 (1) ◽  
pp. 67 ◽  
Author(s):  
MIKE THIV ◽  
J. ALFREDO REYES-BETANCORT ◽  
ORI FRAGMAN-SAPIR
Keyword(s):  
Morphometric Analysis ◽  
Species Delimitation ◽  
Phylogenetic Trees ◽  
Morphological Analysis ◽  
Phylogenetic Analyses ◽  
Life Forms ◽  
Clear Separation ◽  
Taxonomic Treatment ◽  
Molecular Phylogenetic ◽  
The Mediterranean

The distinction of the perennial Aristida coerulescens from the annual A. adscensionis and its taxonomic treatment has been subject of long discussions. We here include accessions from the Mediterranean and Macaronesia for molecular phylogenetic analyses and conducted a morphometric analysis. A lineage of A. adscensionis, A. coerulescens and A. effusa is well supported in phylogenetic trees. Moreover, a group of Mediterranean, Macaronesia and Arabian A. coerulescens and A. adscensionis is revealed where both taxa are intermingled. A morphological analysis of traditionally used spikelet characters did not indicate a clear separation of both taxa. We therefore conclude that A. coerulescens should best be treated as synonym of A. adscensionis. The differential character of annual and perennial life forms seems to be plastic in this taxon indicating rapid shifts between these two strategies. 

scholarly journals Genetic Diversity and Population Divergence of a Rare, Endemic Grass (Elymus breviaristatus) in the Southeastern Qinghai-Tibetan Plateau

2019 ◽  
Vol 11 (20) ◽  
pp. 5863 ◽  
Author(s):  
Qingqing Yu ◽  
Qian Liu ◽  
Yi Xiong ◽  
Yanli Xiong ◽  
Zhixiao Dong ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Tibetan Plateau ◽  
Isolation By Distance ◽  
Genetic Distances ◽  
Conservation Strategy ◽  
Conservation Strategies ◽  
Grass Species ◽  
Population Divergence ◽  
High Genetic Diversity ◽  
Widespread Species

Elymus breviaristatus is a grass species only distributed in the southeast of Qinghai-Tibetan Plateau (QTP), which has suffered from serious habitat fragmentation. Therefore, understanding patterns of genetic diversity within and among natural E. breviaristatus populations could provide insight for future conservation strategies. In this study, sequence-related amplified polymorphism markers were employed to investigate the genetic diversity and hierarchical structure of seven E. breviaristatus populations from QTP, China. Multiple measures of genetic diversity indicated that there is low to moderate genetic variation within E. breviaristatus populations, consistent with its presumed mating system. In spite of its rarity, E. breviaristatus presented high genetic diversity that was equivalent to or even higher than that of widespread species. Bayesian clustering approaches, along with clustering analysis and principal coordinate analysis partitioned the studied populations of E. breviaristatus into five genetic clusters. Differentiation coefficients (Fst, GST, etc.) and AMOVA analysis revealed considerable genetic divergence among different populations. BARRIER analyses indicated that there were two potential barriers to gene flow among the E. breviaristatus populations. Despite these patterns of differentiation, genetic distances between populations were independent of geographic distances (r = 0.2197, p = 0.2534), indicating little isolation by distance. Moreover, despite detecting a common outlier by two methods, bioclimatic factors (altitude, annual mean temperature, and annual mean precipitation) were not related to diversity parameters, indicating little evidence for isolation caused by the environment. These patterns of diversity within and between populations are used to propose a conservation strategy for E. breviaristatus.

Morphological and molecular evidence for a new species of the genus Panolis Hübner, [1821] (Lepidoptera: Noctuidae)

Zootaxa ◽  
2019 ◽  
Vol 4565 (4) ◽  
pp. 523
Author(s):  
XUAN AN ◽  
MAMORU OWADA ◽  
MIN WANG ◽  
HOU-SHUAI WANG
Keyword(s):  
New Species ◽  
Cytochrome C Oxidase ◽  
Phylogenetic Analyses ◽  
Species Group ◽  
Molecular Evidence ◽  
Mitochondrial Cytochrome ◽  
Molecular Phylogenetic ◽  
Lepidoptera Noctuidae ◽  
A New Species ◽  
I Gene

A new species of the genus Panolis Hübner, [1821], P. xundian sp. nov., is described and illustrated from southwestern China. It is well-defined morphologically by the male genitalia, with a well-developed pollex at the distal terminal of the sacculus and a broad, ventrally concave cucullus, the female corpus bursae with four long signum-stripes. Based on a 658 bp segment of the mitochondrial cytochrome c oxidase subunit I gene, we report the pairwise genetic distance of 2.5% from its allied species P. exquisita Draudt, 1950. Molecular phylogenetic analyses using three genes (2189 bp in total length) indicate that the new species belongs to the P. exquisita species group. 

scholarly journals Distribution and phylogenetic diversity of Anopheles species in malaria endemic areas of Honduras in an elimination setting

2020 ◽  
Author(s):  
Denis Escobar ◽  
Krisnaya Ascencio ◽  
Andrés Ortiz ◽  
Adalid Palma ◽  
Gustavo Fontecha
Keyword(s):  
Genetic Diversity ◽  
Phylogenetic Analyses ◽  
Public Health Problem ◽  
Abundant Species ◽  
Malaria Vectors ◽  
Morphological Identification ◽  
High Genetic Diversity ◽  
Homogeneous Population ◽  
Molecular Approaches ◽  
Endemic Areas

Abstract Background: Anopheles mosquitoes are the vectors of malaria, one of the most important infectious diseases in the tropics. More than 500 Anopheles species have been described worldwide, and more than 30 are considered a public health problem. In Honduras, information on the distribution of Anopheles spp. and its genetic diversity is scarce. This study aimed to describe the distribution and genetic diversity of Anopheles mosquitoes in Honduras. Methods: Mosquitoes were captured in 8 locations in 5 malaria endemic departments during 2019. Two collection methods were used. Adult anophelines were captured outdoors using CDC light traps and by aspiration of mosquitoes at rest. The morphological identification was performed using taxonomic keys. Genetic analyses included the sequencing of a partial region of the cytochrome oxidase I gene (COI) and the ribosomal internal transcribed spacer 2 (ITS2). Results: A total of 1320 anophelines were collected and identified through morphological keys. Seven Anopheles species were identified. Anopheles albimanus was the most widespread and abundant species (74.02%). To confirm the morphological identification of the specimens, 175 and 122 sequences were obtained for COI and ITS2 respectively. Both markers confirmed the morphological identification. COI showed a greater nucleotide diversity than ITS2 in all species. High genetic diversity was observed within the populations of An. albimanus while An. darlingi proved to be a highly homogeneous population. Phylogenetic analyses revealed clustering patterns in An. darlingi and An. neivai in relation to specimens from South America. New sequences for An. crucians, An. vestitipennis, and An. neivai are reported in this study.Conclusions: Here we report the distribution and genetic diversity of Anopheles species in endemic areas of malaria transmission in Honduras. According to our results, both taxonomic and molecular approaches are useful tools in the identification of anopheline mosquitoes. However, both molecular markers differ in their ability to detect intraspecific genetic diversity. These results provide supporting data for a better understanding of the distribution of malaria vectors in Honduras.

Diversity of Xanthoparmelia (Parmeliaceae) species in Mexican xerophytic scrub vegetation, evidenced by molecular, morphological and chemistry data

2021 ◽  
Vol 78 (1) ◽  
pp. e107
Author(s):  
Alejandrina Barcenas-Peña ◽  
Steven D. Leavitt ◽  
Felix Grewe ◽  
H. Thorsten Lumbsch
Keyword(s):  
Species Delimitation ◽  
Phylogenetic Analyses ◽  
Species Level ◽  
Integrative Approach ◽  
Molecular Evidence ◽  
Central Mexico ◽  
Phylogenetic Reconstructions ◽  
The World ◽  
Molecular Phylogenetic ◽  
Chemical Characters

The genus Xanthoparmelia is the largest genus of lichen- forming fungi with about 800 species worldwide. Xanthoparmelia is also common in the deserts of central Mexico, but only a few molecular studies exist on its species’ diversity in this region. In this study, we sampled 38 Xanthoparmelia species from around the world including species from the xerophytic scrubs of central Mexico to assess the diversity using an integrative approach. Molecular phylogenetic analyses were performed using a combination of the ITS, mtSSU and nuLSU genetic markers. We evaluated our phylogenetic results in a context of traditional morphological and chemical characters. The combined evidence of molecular, morphological, and chemical data identified a total of 18 Xanthoparmelia species-level lineages occurring in central Mexico. However, numerous traditionally circumscribed species did not form monophyletic groups in the molecular phylogenetic reconstructions. This conflict indicates that taxonomy and species delimitation in the genus Xanthoparmelia requires revision and emphasizes the importance of molecular evidence for more robust species delimitations in this genus.

Intra- and interspecific genetic diversity of New Zealand hairworms (Nematomorpha)

Parasitology ◽  
2017 ◽  
Vol 144 (8) ◽  
pp. 1026-1040 ◽  
Author(s):  
ZACHARY J. C. TOBIAS ◽  
ARUN K. YADAV ◽  
ANDREAS SCHMIDT-RHAESA ◽  
ROBERT POULIN
Keyword(s):  
Genetic Diversity ◽  
New Zealand ◽  
Sequence Data ◽  
Phylogenetic Analyses ◽  
Population Level ◽  
Morphological Classification ◽  
Widespread Species ◽  
Sampling Locations ◽  
Host Parasite ◽  
Eggs And Larvae

SUMMARYHairworms (Nematomorpha) are a little-known group of parasites, and despite having been represented in the taxonomic literature for over a century, the implementation of molecular genetics in studies of hairworm ecology and evolution lags behind that of other parasitic taxa. In this study, we characterize the genetic diversity of the New Zealand nematomorph fauna and test for genetic structure within the most widespread species found. We provide new mitochondrial and nuclear ribosomal sequence data for three previously described species from New Zealand:Gordius paranensis, Parachordodes diblastusandEuchordodes nigromaculatus. We also present genetic data on a previously reported but undescribedGordiussp., as well as data from specimens of a newGordionussp., a genus new for New Zealand. Phylogenetic analyses of CO1 and nuclear rDNA regions correspond with morphological classification based on scanning electron microscopy, and demonstrate paraphyly of the genusGordionusand the potential for cryptic species withinG. paranensis. Population-level analyses ofE. nigromaculatusshowed no genetic differentiation among sampling locations across the study area, in contrast to previously observed patterns in known and likely definitive hosts. Taken together, this raises the possibility that factors such as definitive host specificity, intermediate host movement, and passive dispersal of eggs and larvae may influence host–parasite population co-structure in hairworms.

High genetic diversity and a new cryptic species within the Ephedrus persicae species group (Hymenoptera: Braconidae: Aphidiinae)

Biologia ◽  
2016 ◽  
Vol 71 (12) ◽  
Author(s):  
Andjeljko Petrović ◽  
Korana Kocić ◽  
Katarina Kos ◽  
Milan Plećaš ◽  
Vladimir Žikić ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Molecular Markers ◽  
Cryptic Species ◽  
Species Group ◽  
High Genetic Diversity

AbstractIn this study we used molecular markers to characterize various populations of the

A new species of African Snake-Eyed Skink (Scincidae: Panaspis) from Ethiopia

Zootaxa ◽  
2020 ◽  
Vol 4779 (2) ◽  
pp. 190-200
Author(s):  
TIMOTHY J. COLSTON ◽  
R. ALEXANDER PYRON ◽  
AARON M. BAUER
Keyword(s):  
New Species ◽  
Phylogenetic Analyses ◽  
Type Specimen ◽  
Species Group ◽  
Sub Saharan Africa ◽  
Cryptic Diversity ◽  
Molecular Phylogenetic ◽  
Sub Saharan ◽  
Phylogenetic Revision ◽  
A New Species

A recent molecular phylogenetic revision of the snake-eyed skinks (genus Panaspis Cope, 1868) uncovered extensive cryptic diversity, including several new species from throughout sub-Saharan Africa. Here, we describe one of these from Ethiopia as Panaspis annettesabinae sp. nov. This description is based on a previous molecular phylogeny and morphological, scalation, and coloration data collected from the type specimen. Phylogenetic analyses place the species alone in what we term the P. annettesabinae species group from Ethiopia. This group forms the sister lineage to a large southern African radiation and suggests a potential northern origin for much of the extant diversity of Panaspis. Many new taxa have recently been discovered in the genus and region, and there are several historical records of Panaspis from elsewhere in Ethiopia. Thus, we suggest that the range of this new species (known only from a single specimen at present) may be much larger, and that additional undescribed species may exist in northern sub-Saharan Africa. 

High genetic diversity, distant phylogenetic relationships and intraspecies recombination events among natural populations of Yam mosaic virus: a contribution to understanding potyvirus evolution

Microbiology ◽  
2000 ◽  
Vol 81 (1) ◽  
pp. 243-255 ◽  
Author(s):  
M. Bousalem ◽  
E. J. P. Douzery ◽  
D. Fargette
Keyword(s):  
Genetic Diversity ◽  
Mosaic Virus ◽  
Statistical Tests ◽  
Phylogenetic Analyses ◽  
Natural Populations ◽  
High Genetic Diversity ◽  
Single Clade ◽  
Cultivated Species ◽  
Selection Of

To evaluate the genetic diversity and understand the evolution of Yam mosaic virus (YMV), a highly destructive pathogen of yam (Dioscorea sp.), sequencing was carried out of the C-terminal part of the replicase (NIb), the coat protein (CP) and the 3′-untranslated region (3′-UTR) of 27 YMV isolates collected from the three main cultivated species (Dioscorea alata, the complex Dioscorea cayenensis–Dioscorea rotundata and Dioscorea trifida). YMV showed the most variable CP relative to eight other potyviruses. This high variability was structured into nine distant molecular groups, as revealed by phylogenetic analyses and validated by assessment of the molecular evolutionary noise. No correlation was observed between the CP and 3′-UTR diversities and phylogenies. The most diversified and divergent groups included isolates from Africa. The remaining groups clustered in a single clade and a geographical distinction between isolates from the Caribbean, South America and Africa was observed. The role of the host in the selection of particular isolates was illustrated by the case of a divergent cultivar from Burkina Faso. Phylogenetic topological incongruence and complementary statistical tests highlighted the fact that recombination events, with single and multiple crossover sites, largely contributed to the evolution of YMV. We hypothesise an African origin of YMV from the yam complex D. cayenensis–D. rotundata, followed by independent transfers to D. alata and D. trifida during virus evolution.

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