scholarly journals The queen conch mitogenome: intra- and interspecific mitogenomic variability in Strombidae and phylogenetic considerations within the Hypsogastropoda

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Salima Machkour-M’Rabet ◽  
Margaret M. Hanes ◽  
Josué Jacob Martínez-Noguez ◽  
Jorge Cruz-Medina ◽  
Francisco J. García-De León
Keyword(s):  
Nucleotide Diversity ◽  
Marine Species ◽  
Interspecific Variation ◽  
Phylogenetic Position ◽  
Queen Conch ◽  
Interspecific Divergence ◽  
Mexican Caribbean ◽  
Close Relationship ◽  
Phylogenomic Analyses ◽  
Lineage Diversification

AbstractAliger gigas is an economically important and vulnerable marine species. We present a new mitogenome of A. gigas from the Mexican Caribbean and use the eight publicly available Strombidae mitogenomes to analyze intra- and interspecific variation. We present the most complete phylogenomic understanding of Hypsogastropoda to date (17 superfamilies, 39 families, 85 genera, 109 species) to revisit the phylogenetic position of the Stromboidea and evaluate divergence times throughout the phylogeny. The A. gigas mitogenome comprises 15,460 bp including 13 PCGs, 22 tRNAs, and two rRNAs. Nucleotide diversity suggested divergence between the Mexican and Colombian lineages of A. gigas. Interspecific divergence showed high differentiation among Strombidae species and demonstrated a close relationship between A. gigas and Strombus pugilis, between Lambis lambis and Harpago chiragra, and among Tridentarius dentatus/Laevistrombus canarium/Ministrombus variabilis. At the intraspecific level, the gene showing the highest differentiation is ATP8 and the lowest is NAD4L, whereas at the interspecific level the NAD genes show the highest variation and the COX genes the lowest. Phylogenomic analyses confirm that Stromboidea belongs in the non-Latrogastropoda clade and includes Xenophoridea. The phylogenomic position of other superfamilies, including those of previously uncertain affiliation, is also discussed. Finally, our data indicated that Stromboidea diverged into two principal clades in the early Cretaceous while Strombidae diversified in the Paleocene, and lineage diversification within A. gigas took place in the Pleistocene.

scholarly journals Intraspecific and interspecific variation in 5S RNA genes are decoupled in diploid wheat relatives.

Genetics ◽  
1995 ◽  
Vol 140 (1) ◽  
pp. 325-343 ◽  
Author(s):  
E A Kellogg ◽  
R Appels
Keyword(s):  
Nucleotide Diversity ◽  
Diploid Species ◽  
Interspecific Variation ◽  
Species Variation ◽  
5S Rna ◽  
Interspecific Divergence ◽  
Ribosomal Operon ◽  
Form Part ◽  
5S Rna Genes ◽  
Rna Genes

Abstract 5S RNAs form part of the ribosome in most organisms. In some, e.g., prokaryotes and some fungi, the genes are part of the ribosomal operon, but in most eukaryotes they are in tandem arrays of hundreds to thousands of copies separate from the main ribosomal array. 5S RNA genes can be aligned across kingdoms. We were therefore surprised to find that, for 28 diploid species of the wheat tribe (Triticeae), nucleotide diversity within an array is up to 6.2% in the genes, not significantly different from that of the nontranscribed spacers. Rates of concerted evolution must therefore be insufficient to homogenize the entire array. Between species, there are significantly fewer fixed differences in the gene than would be expected, given the high within-species variation. In contrast, the amount of variation between species in the spacer is the same as or greater than that within individuals. This leads to a paradox. High variation within an individual suggests that there is little selection on any particular gene within an array. But conservation of the gene across species implies that polymorphisms are periodically eliminated at a rate approximately equal to or greater than that of speciation. Levels of intraspecific polymorphism and interspecific divergence are thus decoupled. This implies that selective mechanisms exist to eliminate mutations in the gene without also affecting the spacer.

scholarly journals Patterns of DNA Variability at X-Linked Loci in Mus domesticus

Genetics ◽  
1997 ◽  
Vol 147 (3) ◽  
pp. 1303-1316
Author(s):  
Michael W Nachman
Keyword(s):  
Drosophila Melanogaster ◽  
X Chromosome ◽  
House Mouse ◽  
Recombination Rate ◽  
Nucleotide Diversity ◽  
Mus Domesticus ◽  
Substantial Variation ◽  
Intraspecific Polymorphism ◽  
Recombination Rates ◽  
Interspecific Divergence

Introns of four X-linked genes (Hprt, Plp, Glra2, and Amg) were sequenced to provide an estimate of nucleotide diversity at nuclear genes within the house mouse and to test the neutral prediction that the ratio of intraspecific polymorphism to interspecific divergence is the same for different loci. Hprt and Plp lie in a region of the X chromosome that experiences relatively low recombination rates, while Glra2 and Amg lie near the telomere of the X chromosome, a region that experiences higher recombination rates. A total of 6022 bases were sequenced in each of 10 Mus domesticus and one M. caroli. Average nucleotide diversity (π) for introns within M. domesticus was quite low (π = 0.078%). However, there was substantial variation in the level of heterozygosity among loci. The two telomeric loci, Glra2 and Amg, had higher ratios of polymorphism to divergence than the two loci experiencing lower recombination rates. These results are consistent with the hypothesis that heterozygosity is reduced in regions with lower rates of recombination, although sampling of additional genes is needed to establish whether there is a general correlation between heterozygosity and recombination rate as in Drosophila melanogaster.

Resolving the Lourinia armata (Claus, 1866) complex with remarks on the monophyletic status of Louriniidae, Monard 1927 (Copepoda: Harpacticoida)

Zootaxa ◽  
2021 ◽  
Vol 5051 (1) ◽  
pp. 346-386
Author(s):  
SÜPHAN KARAYTUĞ ◽  
SERDAR SAK ◽  
ALP ALPER ◽  
SERDAR SÖNMEZ
Keyword(s):  
Comparative Evaluation ◽  
Species Complex ◽  
Detailed Examination ◽  
The Other ◽  
Phylogenetic Position ◽  
Nicobar Island ◽  
Other Hand ◽  
The Family ◽  
Close Relationship ◽  
Almost All

An attempt was made to test if Lourinia armata (Claus, 1866)—as it is currently diagnosed—represents a species complex. Detailed examination and comparisons of several specimens collected from different localities suggest that L. armata indeed represents a complex of four closely related morphospecies that can be differentiated from one another by only detailed observations. One of the four species is identified as Lourinia aff. armata and the other three species are described as new to science and named as Lourinia wellsi sp. nov., L. gocmeni sp. nov., and L. aldabraensis sp. nov. Detailed review of previous species records indicates that the genus Lourinia Wilson, 1924 is distributed worldwide. Ceyloniella nicobarica Sewell, 1940, originally described from Nicobar Island and previously considered a junior subjective synonym of L. armata is reinstated as Lourinia nicobarica (Sewell, 1940) comb. nov. on the basis of the unique paddle-shaped caudal ramus seta V. It is postulated that almost all of these records are unreliable in terms of representing true Lourinia aff. armata described herein. On the other hand, the comparative evaluation of the illustrations and descriptions in the published literature indicates the presence of several new species waiting to be discovered in the genus Lourinia.                 It has been determined that, according to updated modern keys, the recent inclusion of the monotypic genus Archeolourinia Corgosinho & Schizas, 2013 in the Louriniidae is not justified since Archeolourinia shermani Corgosinho & Schizas, 2013 does not belong to this family but should be assigned to the Canthocamptidae. On the other hand, it has been argued that the exact phylogenetic position of the Louriniidae still remains problematic since none of the diagnostic characters supports the monophyly of the family within the Oligoarthra. It has also been argued that the close relationship between Louriniidae and Canthocamptidae is supported since both families share the homologous sexual dimorphism (apophysis) on P3 endopod. The most important characteristic that can possibly be used to define Louriniidae is the reduction of maxilliped.  

Morphology of a unique ophidiid, Hypopleuron caninum Radcliffe 1913 (Ophidiiformes, Ophidiidae, Neobythitinae), suggesting a close relationship with the family Carapidae

Zootaxa ◽  
2018 ◽  
Vol 4521 (4) ◽  
pp. 499
Author(s):  
SHINPEI OHASHI
Keyword(s):  
Phylogenetic Position ◽  
Dorsal Fin ◽  
The Family ◽  
Close Relationship ◽  
Pelvic Fin

Osteological and myological characters of the ophidiid Hypopleuron caninum are described here in detail. In addition to well-known characters of Ophidiidae (e.g., anal-fin origin well posterior to dorsal-fin origin; barbel-like pelvic fin; many scales), many unique or rare conditions were also recognized, including predorsal bone and maxilla condition, and canine teeth on the premaxilla, which were suggestive of a relationship with Carapidae. Furthermore, the predorsal bone appear to be homologous with the vexillar support, a carapid synapomorphy. Although several characters differ from carapid counterparts (e.g., more anterior anal-fin origin and scales absent in Carapidae), some intermediate conditions between Ophidiidae and Carapidae are apparent in Hypopleuron caninum, which may therefore occupy an intermediate phylogenetic position between the two families. A unique morphology of small second infraorbital bone is recognized in all ophidiiform species observed in this study, and it may be a synapomorphic character of the order Ophidiiformes. 

scholarly journals Resurrection of the Butterfly-winged Comber, Serranus papilionaceus Valenciennes, 1832 (Teleostei, Serranidae) and its phylogenetic position within genus Serranus

ZooKeys ◽  
2021 ◽  
Vol 1017 ◽  
pp. 111-126
Author(s):  
Adriana Vella ◽  
Noel Vella ◽  
Carolina Acosta-Díaz
Keyword(s):  
Conservation Status ◽  
Valid Species ◽  
Phylogenetic Position ◽  
Mitochondrial Coi ◽  
Interspecific Divergence ◽  
Population Conservation ◽  
Status Assessment ◽  
Morphological Differences ◽  
Species Specific ◽  
High Level

The family Serranidae is represented by 92 genera and 579 valid species, with the genus Serranus Cuvier, 1816, containing 30 species. In this study, specimens of Butterfly-winged Comber, Serranus papilionaceus Valenciennes, 1832, were collected from the Canary Islands and compared morphologically and genetically to Painted Comber, Serranus scriba (Linnaeus, 1758), from the Mediterranean Sea. Morphological differences, especially in the colour banding pattern, were corroborated by genetic differences in mitochondrial (COI and ND2) and nuclear (Rhod and PTR) markers. The mitochondrial DNA markers revealed a high level of divergence and no shared haplotypes between the two species (interspecific divergence: COI 4.31%; ND2 8.68%), and a phylogenetic analysis showed that these two species are closely related sister species sharing common ancestry. This study is therefore offering to resurrect S. papilionaceus Valenciennes, 1832 as a valid species increasing the number of eastern Atlantic Serranus species to 11. This should direct new species-specific research, including its population conservation status assessment across its distribution.

Two new species of Roccellaceae (Ascomycota: Arthoniales) from Brazil, with the description of the new genus Sergipea

2013 ◽  
Vol 45 (5) ◽  
pp. 627-634 ◽  
Author(s):  
André APTROOT ◽  
Damien ERTZ ◽  
Edvaneide Leandro de LIMA ◽  
Katia Almeida de JESUS ◽  
Leonor Costa MAIA ◽  
...  
Keyword(s):  
New Species ◽  
New Genus ◽  
Phylogenetic Position ◽  
Generic Type ◽  
Bright Orange ◽  
Two New Species ◽  
Basal Branch ◽  
Close Relationship ◽  
Relationship Of ◽  
A New Species

AbstractThe new lichen genus Sergipea M. Cáceres, Ertz & Aptroot is described in the Roccellaceae, based on the new species Sergipea aurata M. Cáceres, Ertz & Aptroot from NE Brazil. The species was found in a remnant of Atlantic transition forest in Sergipe. It is similar in many respects to species of the genus Enterographa, but it is characterized by bright orange stromata, due to the presence of an anthraquinone, and a thallus with a somewhat byssoid hypothallus. Phylogenetically it is close to the genera Dichosporidium and Erythrodecton. The phylogenetic position of the generic type of Dichosporidium confirms the close relationship of the genus to Erythrodecton in the basal branch of the Roccellaceae. A new species of Enterographa is also described from NE Brazil. Enterographa rotundata E. L. Lima, M. Cáceres & Aptroot has solitary, round apothecia, which is unusual in this genus with mainly elongated apothecia or punctiform apothecia arranged in lines. It was found in Caatinga forest in Pernambuco.

scholarly journals Phylogeny and morphology of genus Nephrocytium (Sphaeropleales, Chlorophyceae, Chlorophyta) from China

Phytotaxa ◽  
2017 ◽  
Vol 319 (1) ◽  
pp. 84 ◽  
Author(s):  
XUDONG LIU ◽  
HUAN ZHU ◽  
BENWEN LIU ◽  
GUOXIANG LIU ◽  
ZHENGYU HU
Keyword(s):  
Phylogenetic Analyses ◽  
Light And Electron Microscopy ◽  
Taxonomic Position ◽  
Phylogenetic Position ◽  
Phytoplankton Communities ◽  
Close Phylogenetic Relationship ◽  
The Family ◽  
Close Relationship ◽  
Molecular Phylogenetic

The genus Nephrocytium Nägeli is a common member of phytoplankton communities that has a distinctive morphology. Its taxonomic position is traditionally considered to be within the family Oocystaceae (Trebouxiophyceae). However, research on its ultrastructure is rare, and the phylogenetic position has not yet been determined. In this study, two strains of Nephrocytium, N. agardhianum Nägeli and N. limneticum (G.M.Smith) G.M.Smith, were identified and successfully cultured in the laboratory. Morphological inspection by light and electron microscopy and molecular phylogenetic analyses were performed to explore the taxonomic position. Ultrastructure implied a likely irregular network of dense and fine ribs on the surface of the daughter cell wall that resembled that of the genus Chromochloris Kol & Chodat (Chromochloridaceae). Phylogenetic analyses revealed that Nephrocytium formed an independent lineage in the order Sphaeropleales (Chlorophyceae) with high support values and a close phylogenetic relationship with Chromochloris. Based on combined morphological, ultrastructural and phylogenetic data, we propose a re-classification of Nephrocytium into Sphaeropleales, sharing a close relationship with Chromochloris.

The genetic analysis of new Polish strains of European brown hare syndrome virus

2014 ◽  
Vol 17 (2) ◽  
pp. 353-355
Author(s):  
E. Kwit ◽  
M. Chrobocińska ◽  
Z. Grądzki ◽  
Ł. Jarosz ◽  
B. Majer-Dziedzic ◽  
...  
Keyword(s):  
Genetic Analysis ◽  
Phylogenetic Position ◽  
Brown Hare ◽  
Gene Encoding ◽  
European Brown Hare ◽  
Close Relationship ◽  
Provinces Of Poland ◽  
Pcr Method ◽  
European Brown Hare Syndrome ◽  
Hare Population

Abstract In this paper we describe recently occurring outbreaks of European brown hare syndrome (EBHS) in a captive hare population. The aim of our study was to evaluate the phylogenetic position of detected Polish strains compared to other European strains of EBHSV. Investigations were undertaken in hares from different provinces of Poland. Liver or spleen samples were tested for viral RNA using the RT-nested PCR method and the products were subsequently sequenced. The genetic analysis was based on the fragment of gene encoding viral capsid protein; it revealed a high homology and close relationship between Polish and European EBHSV strains isolated between 2001 and 2011

scholarly journals Phylogenetic investigation of skin sloughing rates in frogs: relationships with skin characteristics and disease-driven declines

2019 ◽  
Vol 286 (1896) ◽  
pp. 20182378 ◽  
Author(s):  
Michel E. B. Ohmer ◽  
Rebecca L. Cramp ◽  
Craig R. White ◽  
Peter S. Harlow ◽  
Michael S. McFadden ◽  
...  
Keyword(s):  
Batrachochytrium Dendrobatidis ◽  
Phylogenetic Signal ◽  
Interspecific Variation ◽  
Phylogenetic Position ◽  
Turnover Rates ◽  
Amphibian Skin ◽  
Amphibian Species ◽  
Wide Range ◽  
Skin Morphology ◽  
And Function

Amphibian skin is highly variable in structure and function across anurans, and plays an important role in physiological homeostasis and immune defence. For example, skin sloughing has been shown to reduce pathogen loads on the skin, such as the lethal fungus Batrachochytrium dendrobatidis ( Bd ), but interspecific variation in sloughing frequency is largely unknown. Using phylogenetic linear mixed models, we assessed the relationship between skin turnover rate, skin morphology, ecological traits and overall evidence of Bd -driven declines. We examined skin sloughing rates in 21 frog species from three continents, as well as structural skin characteristics measured from preserved specimens. We found that sloughing rate varies significantly with phylogenetic group, but was not associated with evidence of Bd -driven declines, or other skin characteristics examined. This is the first comparison of sloughing rate across a wide range of amphibian species, and creates the first database of amphibian sloughing behaviour. Given the strong phylogenetic signal observed in sloughing rate, approximate sloughing rates of related species may be predicted based on phylogenetic position. While not related to available evidence of declines, understanding variation in sloughing rate may help explain differences in the severity of infection in genera with relatively slow skin turnover rates (e.g. Atelopus ).

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