A morphological and molecular study of adults and metacercariae of Hysteromorpha triloba (Rudolpi, 1819), Lutz 1931 (Diplostomidae) from the Neotropical region

2018 ◽  
Vol 93 (1) ◽  
pp. 91-99 ◽  
Author(s):  
A.L. Sereno-Uribe ◽  
A. López-Jimenez ◽  
L. Andrade-Gómez ◽  
M. García-Varela
Keyword(s):  
Dna Sequences ◽  
Developmental Stages ◽  
Phylogenetic Analyses ◽  
Mitochondrial Gene ◽  
Molecular Study ◽  
Neotropical Region ◽  
The Body ◽  
Internal Transcribed Spacers ◽  
Nuclear Ribosomal Dna ◽  
Nearctic Region

AbstractAdults of Hysteromorpha triloba (Rudolpi, 1819), Lutz, 1931 inhabit primarily the intestine of cormorants across the globe, whereas metacercariae have been found in the body cavity of freshwater fishes of the families Cyprinidae, Ictaluridae, Ariidae, Pimelodidae and Catostomidae. In this study, adults and metacercariae identified as H. triloba were collected from the Neotropical cormorant (Nannopterum brasilianus) and from the Mexican tetra fish (Astyanax mexicanus) from the Gulf of Mexico and Pacific Ocean slopes in the Neotropical region. Partial DNA sequences of the mitochondrial gene cytochrome c oxidase subunit I (cox 1) and the internal transcribed spacers (ITS1, 5.8S and ITS2) of nuclear ribosomal DNA were generated for both developmental stages, and were compared with available sequences of H. triloba from the Nearctic region. The genetic divergence between metacercariae and adults of H. triloba from the Neotropical and Nearctic region (Canada) associated with the double-crested cormorant (Nannopterum auritus), ranged from 0 to 5.5% for cox 1 and from 0 to 0.2% for ITS. Phylogenetic analyses inferred with both molecular markers using maximum likelihood and Bayesian inference placed the adults and metacercariae in a single clade, confirming that both stages are conspecific. Our data confirmed that H. triloba is a widely distributed species across the Americas, parasitizing both the Neotropical and Nearctic cormorants in Argentina, Brazil, Venezuela, Mexico, USA and Canada.

scholarly journals Phylogenetics of Taxus Using the Internal Transcribed Spacers of Nuclear Ribosomal DNA and Plastid trnL-F Regions

Horticulturae ◽  
2020 ◽  
Vol 6 (1) ◽  
pp. 19
Author(s):  
Patricia Coughlan ◽  
James C. Carolan ◽  
Ingrid L. I. Hook ◽  
Lisa Kilmartin ◽  
Trevor R. Hodkinson
Keyword(s):  
Dna Sequences ◽  
Phylogenetic Analyses ◽  
Intergenic Spacer ◽  
Its Region ◽  
Single Species ◽  
Internal Transcribed Spacers ◽  
Nuclear Ribosomal Dna ◽  
Trnl Intron ◽  
Group Status ◽  
Haplotype Networks

Taxus is a genus of trees and shrubs with high value in horticulture and medicine as a source of the anticancer drug paclitaxel. The taxonomy of the group is complex due to the lack of diagnostic morphological characters and the high degree of similarity among species. Taxus has a wide global geographic distribution and some taxonomists recognize only a single species with geographically defined subgroups, whereas others have described several species. To address these differences in taxonomic circumscription, phylogenetic analyses were conducted on DNA sequences using Maximum Likelihood, Bayesian Inference and TCS haplotype networks on single and combined gene regions obtained for the nuclear ribosomal ITS region and the plastid trnL intron and trnL-F intergenic spacer. Evidence is presented for the sister group status of Pseudotaxus to Taxus and the inclusion of Amentotaxus, Austrotaxus, Cephalotaxus and Torreya within Taxaceae. Results are consistent with the taxonomic recognition of nine species: T. baccata, T. brevifolia, T. canadensis, T. cuspidata, T. floridana, T. fuana, T. globosa, T. sumatrana and T. wallichiana, but evidence is found for less species distinction and considerable reticulation within the T. baccata, T. canadensis and T. cuspidata group. We compare the results to known taxonomy, biogeography, present new leaf anatomical data and discuss the origins of the hybrids T. ×media and T. ×hunnewelliana.

scholarly journals From morphology to molecules: a combined source approach to untangle the taxonomy ofClessinia(Gastropoda, Odontostomidae), endemic land snails from the Dry Chaco ecoregion

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e5986 ◽  
Author(s):  
Maria Gabriela Cuezzo ◽  
Maria Jose Miranda ◽  
Roberto Eugenio Vogler ◽  
Ariel Anibal Beltramino
Keyword(s):  
Species Identification ◽  
Dna Sequences ◽  
Phylogenetic Analyses ◽  
Molecular Study ◽  
Genetic Distances ◽  
Land Snails ◽  
The Body ◽  
Shell Shape ◽  
Geometric Morphometric ◽  
Morphometric Analyses

BackgroundLand gastropods of the Dry Chaco merit special attention because they comprise a highly diverse but barely studied group.ClessiniaDoering, 1875 are typical inhabitants of this ecoregion. The inclusion of their distribution areas intoSpixiarange, their shell shape similarities, and a former molecular study raised doubts on the monophyly of this genus. The present study review the species ofClessinia, under a morphological, geometric morphometrics, and molecular combined approach.MethodsAdults were collected, photographed, measured, and dissected for anatomical studies. Shell ultrastructure was studied with scanning electron microscope. Geometric morphometric analyses on shells were performed testing if they gave complementary information to anatomy. Two mitochondrial genes, and a nuclear region were studied. Phylogenetic reconstructions to explore the relationships of DNA sequences here obtained to those ofClessiniaandSpixiaspecies from GenBank were performed.ResultsSpecies description on shell, periostracal ornamentation and anatomy is provided. We raised formerClessinia cordovana striatato species rank, naming it asClessinia tulumbensissp. nov. The periostracum, consisting of hairs and lamellae, has taxonomic importance for species identification. Shell morphometric analyses, inner sculpture of penis and proportion of the epiphallus and penis, were useful tools to species identification. Nuclear markers do not exhibit enough genetic variation to determine species relationships. Based on the mitochondrial markers, genetic distances amongClessiniaspecies were greater than 10%, and whileC. cordovana,C. nattkemperi, andC. pagodawere recognized as distinct evolutionary genetic species, the distinction betweenC. stelzneriandC. tulumbensissp. nov. was not evident.ClessiniaandSpixiawere paraphyletic in the molecular phylogenetic analyses. Species ofClessiniahere treated have narrow distributional areas and are endemic to the Chaco Serrano subecoregion, restricted to small patches within the Dry Chaco.ClessiniaandSpixiaare synonymous, and the valid name of the taxon should beClessiniaDoering, 1875 which has priority overSpixiaPilsbry & Vanatta, 1894.DiscussionOur results support the composition ofC. cordovanacomplex by three species,C. cordovana,C. stelzneri, andC. tulumbensissp. nov. The low genetic divergence betweenC. stelzneriandC. tulumbensissp. nov. suggests that they have evolved relatively recently. The formerSpixiaandClessiniaare externally distinguished becauseClessiniahas a detached aperture from the body whorl forming a cornet, periostracal microsculpture extended over dorsal portion of the peristome, five inner teeth on the shell aperture instead of three–four found inSpixia. Morphological similarities exists between both genera in shell shape, type of periostracum microsculpture, reproductive anatomy, besides the overlap in geographic ranges.

A new species of Chlorociboria (Helotiales, Ascomycota) on herbaceous stems from China

Phytotaxa ◽  
2017 ◽  
Vol 312 (1) ◽  
pp. 111
Author(s):  
HUAN-DI ZHENG ◽  
WEN-YING ZHUANG
Keyword(s):  
New Species ◽  
Dna Sequences ◽  
Internal Transcribed Spacer ◽  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Central China ◽  
Nuclear Ribosomal Dna ◽  
Light Blue ◽  
Ectal Excipulum ◽  
A New Species

A new species, namely Chlorociboria herbicola, is discovered on herbaceous stems in central China. Morphologically, the new fungus is distinctive by the combination of light blue-green apothecia, rectangular cells in ectal excipulum, and elongate-ellipsoidal ascospores with rounded ends. Phylogenetic analyses of the internal transcribed spacer and large subunit of nuclear ribosomal DNA sequences confirm its ascription in Chlorociboria and distinction from the known species of the genus.

Species relationships in the dasyurid marsupial genus Pseudantechinus (Marsupialia : Dasyuridae): a re-examination of the taxonomic status of Pseudantechinus roryi

2017 ◽  
Vol 65 (4) ◽  
pp. 240 ◽  
Author(s):  
L. S. Umbrello ◽  
P. A. Woolley ◽  
M. Westerman
Keyword(s):  
Dna Sequences ◽  
Isolation By Distance ◽  
Phylogenetic Analyses ◽  
Mitochondrial Gene ◽  
Taxonomic Status ◽  
Museum Collections ◽  
Species Relationships ◽  
Type Specimens ◽  
Network Analyses ◽  
The Status

The status of Pseudantechinus roryi relative to its congeners has been determined from DNA sequences obtained from both nuclear and mitochondrial gene loci. Although all other recognised species of Pseudantechinus form reciprocally monophyletic lineages in phylogenetic analyses, individuals identified in museum collections as Ps. roryi (including type specimens) were indistinguishable from those identified as Ps. macdonnellensis. Ps. roryi is thus considered to be a synonym of Ps. macdonnellensis. Neighbour-joining network analyses failed to reveal any clear biogeographic differences between populations of Ps. macdonnellensis other than some evidence of isolation by distance.

Spegazzinia camelliae sp. nov. (Didymosphaeriaceae, Pleosprales), a new endophytic fungus from northern Thailand

Phytotaxa ◽  
2021 ◽  
Vol 483 (2) ◽  
pp. 117-128
Author(s):  
NAKARIN SUWANNARACH ◽  
JATURONG KUMLA ◽  
SAISAMORN LUMYONG
Keyword(s):  
Phylogenetic Analyses ◽  
Large Subunit ◽  
Elongation Factor ◽  
Small Subunit ◽  
Internal Transcribed Spacers ◽  
Nuclear Ribosomal Dna ◽  
Full Description ◽  
Translation Elongation ◽  
Spine Length ◽  
Elongation Factor 1 Alpha

A new endophytic ascomycete, described herein as Spegazzinia camelliae, was isolated from leaves of Camellia sinensis var. assamica collected from Nan Province, Thailand. This species is characterized by basauxic conidiophores and dark brown to blackish brown α and β conidia. It can be distinguished from previously described Spegazzinia species by the spine length of the α conidia and the size of the β conidia. Multi-gene phylogenetic analyses of the small subunit (SSU), large subunit (LSU) and internal transcribed spacers (ITS) of the nuclear ribosomal DNA (rDNA) and the translation elongation factor 1-alpha (tef1) genes also support S. camelliae is a distinct new species within Spegazzinia. A full description, color photographs, illustrations and a phylogenetic tree showing the position of S. camelliae are provided.

scholarly journals Morphological and molecular characterisation of Hoplolaimus smokyensis n. sp. (Nematoda: Hoplolaimidae), a lance nematode from Great Smoky Mountains National Park, USA

Nematology ◽  
2019 ◽  
Vol 21 (9) ◽  
pp. 923-935 ◽  
Author(s):  
Xinyuan Ma ◽  
Robert T. Robbins ◽  
Ernest C. Bernard ◽  
Claudia M. Holguin ◽  
Paula Agudelo
Keyword(s):  
Dna Sequences ◽  
National Park ◽  
Phylogenetic Analyses ◽  
Mitochondrial Gene ◽  
Tail Region ◽  
Head Region ◽  
Lateral Field ◽  
Great Smoky Mountains ◽  
Smoky Mountains ◽  
Lance Nematode

Summary Hoplolaimus smokyensis n. sp. is a new species of lance nematode collected in Great Smoky Mountains National Park, USA. Females of H. smokyensis n. sp. have a labial region characterised by six, occasionally five, annules. The basal lip annule is subdivided by about 24 longitudinal striae. The stylet averages 47 μm long with robust, tulip-shaped stylet knobs bearing anterior projections. The hemizonid is ca 4 μm anterior to the excretory pore. The lateral field is incompletely areolated and has four continuous incisures from the metacorpus region to the tail region. There are three pharyngeal gland nuclei. Vulval epiptygma are absent. The scutellate phasmids are located one anterior and one posterior to the vulva. The male is shorter than the female and the head region is higher and more rounded than that of the female. The bursa extends to the tail tip and the gubernaculum is large and protrusible and has titillae and a capitulum. Morphologically, H. smokyensis n. sp. is most similar to H. galeatus and H. stephanus, but can be distinguished by differences such as the number of annules and longitudinal striae on the lip region and morphometric values. Hoplolaimus smokyensis n. sp. is also genetically distinct from other species according to comparisons of ribosomal and mitochondrial DNA sequences. Phylogenetic analyses based on ribosomal and mitochondrial gene sequences suggest that H. smokyensis n. sp. is a lineage distinct from related Hoplolaimus species.

scholarly journals Phylogeny of Anopheles (Kerteszia) (Diptera: Culicidae) Using Mitochondrial Genes

Insects ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 324 ◽  
Author(s):  
Karin Kirchgatter ◽  
Lilian de Oliveira Guimarães ◽  
Henrry Hugo Yañez Trujillano ◽  
Fernando Rafael Arias ◽  
Abraham Cáceres ◽  
...  
Keyword(s):  
Dna Sequences ◽  
Species Recognition ◽  
Phylogenetic Analyses ◽  
Mosquito Species ◽  
Relevant Information ◽  
Neotropical Region ◽  
Similar Species ◽  
Serra Do Mar ◽  
Additional Tool ◽  
First Time

Identification of mosquito species is necessary for determining the entomological components of malaria transmission, but it can be difficult in morphologically similar species. DNA sequences are largely used as an additional tool for species recognition, including those that belong to species complexes. Kerteszia mosquitoes are vectors of human and simian malaria in the Neotropical Region, but there are few DNA sequences of Kerteszia species in public databases. In order to provide relevant information about diversity and improve knowledge in taxonomy of Kerteszia species in Peru, we sequenced part of the mitochondrial genome, including the cytochrome c oxidase I (COI) barcode region. Phylogenetic analyses structured all species of mosquitoes collected in Peru into a single clade, separate from the Brazilian species. The Peruvian clade was composed of two lineages, encompassing sequences from Anopheles (Kerteszia) boliviensis and Anopheles (Kerteszia) pholidotus. An. pholidotus sequences were recorded for the first time in Peru, whereas An. boliviensis sequences were for the first time published in the GenBank database. Sequences generated from specimens morphologically identified as Anopheles (Kerteszia) cruzii clustered into three separate clades according to the collection localities of Serra do Mar, Serra da Mantiqueira, and Serra da Cantareira, confirming An. cruzii as a species complex, composed of at least three putative species.

Mitochondrial DNA sequence evidence supporting the recognition of a new North Atlantic Pseudostichopus species (Echinodermata: Holothuroidea)

2004 ◽  
Vol 84 (5) ◽  
pp. 1077-1084 ◽  
Author(s):  
Francisco A. Solís-Marín ◽  
David S.M. Billett ◽  
Joanne Preston ◽  
Alex D. Rogers
Keyword(s):  
Dna Sequences ◽  
Mitochondrial Gene ◽  
Distinct Species ◽  
Molecular Study ◽  
Morphological Characters ◽  
Coi Gene ◽  
Species Status ◽  
Separate Species ◽  
The Family ◽  
A New Species

A new species of the synallactid sea cucumber genus Pseudostichopus is described, P. aemulatus sp. nov., based on genetic (DNA sequences of the mitochondrial gene Cytochrome Oxidase I [COI] gene) and morphological characters. A comparative molecular study with two other species of the same genus (P. villosus and P. mollis) and from a different family (Isostichopus fuscus) was carried out in order to clarify its taxonomic identity. The nucleotide distance between P. aemulatus sp. nov. and P. villosus and P. mollis is sufficient to support distinct species status. The estimated difference in the number of amino acids, coded for by a partially sequenced COI gene, within the species of the family Synallactidae ranged from 4 to 18. The phylogenetic analysis clearly supports separate species status of these sympatric morphotypes, as indicated by the morphological analysis.

Molecular systematics of Australian Podolepis (Asteraceae: Gnaphalieae): evidence from DNA sequences of the nuclear ITS region and the chloroplast matK gene

2000 ◽  
Vol 13 (5) ◽  
pp. 709 ◽  
Author(s):  
N. Konishi ◽  
K. Watanabe ◽  
K. Kosuge
Keyword(s):  
Dna Sequences ◽  
Its Region ◽  
Chromosomal Evolution ◽  
Internal Transcribed Spacers ◽  
Nuclear Ribosomal Dna ◽  
Base Number ◽  
Monophyletic Clade ◽  
Matk Gene ◽  
Nuclear Its ◽  
Generic Relationships

The generic circumscription and intra-generic relationships of the genus Podolepis Labill., with various chromosome numbers from n = 12 to n = 3, were examined by sequences of the internal transcribed spacers (ITS) of nuclear ribosomal DNA and the matK gene of chloroplast DNA. The topology of the ITS tree for 17 species and the matK tree for 18 species of the genus Podolepis sensu Davis (1957) and Anderberg (1991) and 15 taxa from eight related genera (Anderberg 1989, 1991, 1994) are basically concordant. Except for P. georgei Diels andP. kendallii F.Muell., parsimony analyses support the monophyly of the genus Podolepis sensu Davis (1957) and Anderberg (1991). The genera of Asteridea Lindl. and Pterochaeta Steetz are sisters toPodolepis in the combined tree based on the ITS and matK sequences. Within the monophyletic clade of the genus Podolepis, three lineages are identified. The chromosome base number of x = 12 may be ancestral in the genus Podolepis. The dysploidal reduction in chromosome number from n = 12 to n = 10 and 9, from n = 12 to n = 8 and 7, and from n = 12 to n = 11 and 3 in three lineages, respectively, is the primary mode of chromosomal evolution in this genus. Total karyotypic length (= genome size) is much greater in perennials than in annuals within the genus Podolepis. The number of pappus bristles on outer female florets tends to decrease and they are absent in some annuals of this genus, while myxogenic cells on the pericarp become prominent.

European bumblebees (Hymenoptera: Bombini)- phylogenetic relationships inferred from DNA sequences

2002 ◽  
Vol 33 (4) ◽  
pp. 361-386 ◽  
Author(s):  
Vest Pedersen
Keyword(s):  
Maximum Likelihood ◽  
Dna Sequences ◽  
Phylogenetic Trees ◽  
Phylogenetic Analyses ◽  
Mitochondrial Gene ◽  
Elongation Factor ◽  
Nuclear Gene ◽  
The Other ◽  
Elongation Factor 1Α ◽  
Nucleotide Bias

AbstractThe phylogenetics of 40 taxa of European bumblebees were analysed based on PCR amplified and direct sequenced DNA from one region of the mitochondrial gene Cytochrome Oxidase I (1046 bp) and for 26 taxa from two regions in the nuclear gene Elongation Factor 1α (1056 bp). The sequences were aligned to the corresponding sequences in the honey bee. Phylogenetic analyses based on parsimony, as well as maximum likelihood, indicate that the bumblebees can be separated into several well-supported clades. Most of the terminal clades correspond very well with the clades known from former phylogenetic analyses based on morphology and recognized as the subgenera: Mendacibombus, Confusibombus, Psithyrus, Thoracobombus, Megabombus, Rhodobombus, Kallobombus, Alpinobombus, Subterraneobombus, Alpigenobombus, Pyrobombus, Bombus and Melanobombus. All the cuckoo bumblebees form a well-supported clade, the subgenus Psithyrus, within the true bumblebees. All the analyses place Kallobombus as the most basal taxon in contradiction to former analyses. The other deeper nodes of the phylogenetic trees, which are weakly supported, deviate significantly from former published trees - especially the trees based on mtCO-I. Presumably, the reasons are that multiple hits and the strong bias of the bases A and T blur the relationships in the deepest part of the trees. Analyses of the region in mtCO-I show a very strong A+T bias (A+T= 75%), which also indicate preferences in the use of codons with A or T in third positions. In closely related entities, there is only a weak transversion bias (A+T). In the studied regions in EF 1-α, no nucleotide bias is observed. The observed differences in bases between the investigated taxa are relatively small and the gene is too conserved to solve all the questions that the analyses of the deeper nodes using mtCO-I raise.

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