scholarly journals Species Limits and Recent Population History in the Curve-Billed Thrasher

The Condor ◽  
2000 ◽  
Vol 102 (4) ◽  
pp. 881-886 ◽  
Author(s):  
Robert M. Zink ◽  
Rachelle C. Blackwell-Rago
Keyword(s):  
Mitochondrial Dna ◽  
Morphometric Analysis ◽  
Sonoran Desert ◽  
Population History ◽  
Population Increase ◽  
Phenotypic Characteristics ◽  
Species Status ◽  
Base Pairs ◽  
Southern Group ◽  
The Third

Abstract We surveyed 1,115 base pairs of mitochondrial DNA sequence from three gene regions in 66 Curve-billed Thrashers (Toxostoma curvirostre) taken from throughout their range. We found that populations sorted unambiguously into three groups. Two of these groups, the Curvirostre and Palmeri groups, have been known for many years because of their distinctive phenotypic characteristics, and their status was recently confirmed with an intensive morphometric analysis. The third (southern) group consists of populations in Puebla and Oaxaca, Mexico. The strong morphological and mtDNA distinctiveness of the Curvirostre and Palmeri groups suggests that they warrant species status. We recommend that more specimens of the southern group be obtained prior to formal taxonomic recognition of this form. Coalescence analyses suggest that the Curvirostre group has undergone a recent population increase, whereas the Palmeri group seems to have been more stable in its Sonoran Desert range.

Description of a new Episemion species (Cyprinodontiformes: Nothobranchiidae) from northern Gabon and southeastern Equatorial Guinea

Zootaxa ◽  
2006 ◽  
Vol 1361 (1) ◽  
pp. 1 ◽  
Author(s):  
RAINER SONNENBERG ◽  
THOMAS BLUM ◽  
BERNHARD Y. MISOF
Keyword(s):  
Mitochondrial Dna ◽  
Equatorial Guinea ◽  
Monotypic Genus ◽  
Adult Males ◽  
Species Status ◽  
The Third ◽  
Valid Genus ◽  
Coloration Pattern

Episemion krystallinoron sp. nov., the second species in this formerly monotypic genus, is described from the Monts de Cristal in northwestern Gabon and adjacent areas in Equatorial Guinea. It is clearly distinguished from its congener by the coloration pattern of adult males. Species status is also supported by mitochondrial DNA data. Episemion Radda & Pürzl, 1987 is regarded as a valid genus, distinct from all other nothobranchiid genera and probably most closely related to Diapteron Huber & Seegers, 1977 and Kathetys Huber, 1977. It is the third described endemic nothobranchiid species from the Monts de Cristal and adjacent areas.

scholarly journals Genetic Diversities and Historical Dynamics of Native Ethiopian Horse Populations (Equus caballus) Inferred from Mitochondrial DNA Polymorphisms

Genes ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 155
Author(s):  
Kefena Effa ◽  
Sonia Rosenbom ◽  
Jianlin Han ◽  
Tadelle Dessie ◽  
Albano Beja-Pereira
Keyword(s):  
Genetic Diversity ◽  
Mitochondrial Dna ◽  
Genetic Differentiation ◽  
Sequence Divergence ◽  
Dna Polymorphisms ◽  
Base Pairs ◽  
Feral Horses ◽  
Domestic Horses ◽  
D Loop ◽  
Diversity Estimates

Matrilineal genetic diversity and relationship were investigated among eight morphologically identified native Ethiopian horse populations using polymorphisms in 46 mtDNA D-loop sequences (454 base pairs). The horse populations identified were Abyssinian, Bale, Borana, Horro, Kafa, Kundido feral horses, Ogaden and Selale. Mitochondrial DNA D-loop sequences were characterized by 15 variable sites that defined five different haplotypes. All genetic diversity estimates, including Reynolds’ linearized genetic distance, genetic differentiation (FST) and nucleotide sequence divergence (DA), revealed a low genetic differentiation in native Ethiopian horse populations. However, Kundido feral and Borana domestic horses were slightly diverged from the rest of the Ethiopian horse populations. We also tried to shed some light on the matrilineal genetic root of native Ethiopian horses from a network constructed by combining newly generated haplotypes and reference haplotypes deposited in the GenBank for Eurasian type Turkish Anatolian horses that were used as a genetic conduit between Eurasian and African horse populations. Ninety-two haplotypes were generated from the combined Ethio-Eurasian mtDNA D-loop sequences. A network reconstructed from the combined haplotypes using Median-Joining algorithm showed that haplotypes generated from native Ethiopian horses formed separate clusters. The present result encourages further investigation of the genetic origin of native African horses by retrieving additional mtDNA sequences deposited in the GenBank for African and Eurasian type horses.

Species delimitation in the leaf beetle genus Macroplea (Coleoptera, Chrysomelidae) based on mitochondrial DNA, and phylogeographic considerations

2006 ◽  
Vol 37 (4) ◽  
pp. 467-479 ◽  
Author(s):  
Gregor Kölsch ◽  
Bo Vest Pedersen ◽  
Olof Biström
Keyword(s):  
Phylogenetic Analysis ◽  
Mitochondrial Dna ◽  
Species Delimitation ◽  
Mitochondrial Gene ◽  
Leaf Beetle ◽  
Genetic Distances ◽  
Amino Acid Substitutions ◽  
Species Status ◽  
Leaf Beetles ◽  
Gene Coding

AbstractThe genus Macroplea Samouelle, 1819 is a group of highly specialized aquatic leaf beetles occurring in the Palaearctic. Since the members of this genus are morphologically very similar, we addressed the question of species identification and delimitation by analysing the second half of the mitochondrial gene coding for the cytochrome oxidase I (COI) subunit. Species limits are inferred from the multimodal frequency distribution of genetic distances between specimens: low genetic distances within a species are clearly set apart from distances between species. The species status of the hitherto controversial species M. japana (Jacoby, 1885) is confirmed. The pattern of nucleotide and amino acid substitutions is discussed in the light of functional domains of the COI molecule. Although the data are preliminary, the results provide new data on the distribution of the species. Together with the phylogenetic analysis they allow for a discussion of the phylogeography of the genus.

scholarly journals Germination of Balsa Seedlings (Ochroma lagopus Swartz) under Different Sowing Media in East New Britain, Papua New Guinea

2021 ◽  
pp. 73-88
Author(s):  
Boas Malagat ◽  
Kari Iamba
Keyword(s):  
Papua New Guinea ◽  
Seedling Emergence ◽  
Garden Soil ◽  
Gaseous Exchange ◽  
Phenotypic Characteristics ◽  
The Third ◽  
Daily Average ◽  
Emergence Rate ◽  
New Britain ◽  
Local Materials

A good sowing media ensures better anchorage of plants, provides a reservoir of  nutrients and water, and enhance gaseous exchange with the atmosphere. Balsa (Ochroma lagopus Swartz); Vimmy variety, has proven its versatility in producing some of the best phenotypic characteristics such as higher jorquette height, less branching and high log volumes. This experiment was carried out using a combination of three different local materials; local garden soil, pumice soil and sawdust but in different combination ratios aimed to investigate the best combinations. Six treatments were tested: T1= Pure Garden soil, T2= Pumice, T3= Control (75% large coarse sawdust, 25% pure garden soil), T4= Pure Sawdust, T5= 50% medium coarse sawdust, 50% pure soil, and, T6= 33% medium coarse sawdust, 33% Pumice, 33% Pure garden Soil. The daily average germination count in Treatment 5 (50% medium coarse sawdust & 50% pure soil) produced constant germinations from day fifteen (15) to day twenty one (21). Treatments 1, 2, 3, 4 and 6 showed high variations in their daily average germination for the same period but did not produce a constant supply of germinations. Treatment 5 had the highest emergence rate index (ERI=71.76) followed by treatment 1 (ERI=66.59).  Treatment 4 had the third highest seedling emergence (ERI=63.74) followed by treatment 3 (ERI=59.37), treatment 6 (ERI=57.22) and treatment 2 (ERI=53.81) at the lowest continuum. Substrates containing 50% soil and 50% medium coarse sawdust are regarded as better sowing media for O. lagopus seedlings.

scholarly journals A new species of Amphisbaena (Squamata: Amphisbaenidae) from the Orinoquian region of Colombia

2021 ◽  
Vol 71 ◽  
pp. 55-74
Author(s):  
Juan José Torres-Ramírez ◽  
Teddy Angarita-Sierra ◽  
Mario Vargas-Ramírez
Keyword(s):  
Mitochondrial Dna ◽  
New Species ◽  
Phylogenetic Analyses ◽  
Similar Species ◽  
General Knowledge ◽  
Southern Brazil ◽  
Base Pairs ◽  
Northern South America ◽  
Great Genetic Distance ◽  
A New Species

In northern South America, amphisbaenians are rarely seen among the herpetofauna.Thus, general knowledge about them is very poor. During a herpetological survey in 2012 at Casanare, Colombia, we found two specimens of an unusual Amphisbaena. A third specimen sharing the same morphotype labeled Amphisbaena sp. from Vichada department was found deposided in an Colombian reptile collection. Based on morphological analyses together with phylogenetic analyses of 1029 base pairs of the mitochondrial DNA (mtDNA), we describe a new species of Amphisbaena that inhabits in the Orinoquian region of Colombia. The new species is part of a phylogenetic clade together with A. mertensii and A. cunhai (central-southern Brazil), exhibiting a great genetic distance (26.1–28.9%) between the newly identified lineage versus those taxa, and versus the sympatric taxa A. alba and A. fuliginosa. Morphologically, this new Amphisbaena can be distinguished from their congeners by characters combination of number of preocloacal pores, absence of malar scale, postgenial scales and body and caudal annuli counts. Amphisbaena gracilis is on morphology grounds the most similar species. However, the new species can be distinguished from it by having higher body annuli counts, angulus ories aliegned with the edges of the ocular scales and center of frontal scales, less number of large middorsal segments of the first and second body annulus, and rostral scale visible from above. The description of this new Amphisbaena species points out the urgent need to increase the knowledge of worm lizards in Colombia

scholarly journals Molecular Systematics and Patterns of Diversification in Pyrrhura (Psittacidae), with Special Reference to the Picta-Leucotis Complex

The Auk ◽  
2006 ◽  
Vol 123 (3) ◽  
pp. 660-680 ◽  
Author(s):  
Camila C. Ribas ◽  
Leo Joseph ◽  
Cristina Y. Miyaki
Keyword(s):  
Phylogenetic Analysis ◽  
Mitochondrial Dna ◽  
Molecular Systematics ◽  
Neotropical Forests ◽  
The Third ◽  
Species Pairs ◽  
Age Variation ◽  
Mtdna Diversity ◽  
Almost All ◽  
Evolutionary Lineages

AbstractParakeets in the genus Pyrrhura occur in Amazonia and in almost all other major Neotropical forests. Their uneven distribution (with some widespread and several geographically restricted endemic taxa) and complex patterns of plum- age variation have long generated a confused taxonomy. Several taxonomically difficult polytypic species are usually recognized. Here, we present a mitochondrial DNA (mtDNA) phylogenetic analysis of Pyrrhura, with emphasis on the especially problematic picta-leucotis complex, to provide a more robust basis for interpreting the systematics and historical biogeography of the group. Our main findings are that (1) Pyrrhura can be divided into three main evolutionary lineages, one comprising P. cruentata, an Atlantic Forest endemic, the second comprising the picta-leucotis complex, and the third comprising the remaining species; (2) the traditionally recognized species P. picta and P. leucotis are not monophyletic; and (3) most of the species recognized by Joseph (2000, 2002) are diagnosable as independent evolutionary units, with the exception of the following species pairs: P. snethlageae and P. amazonum, P. leucotis and P. griseipectus, and P. roseifrons and P. peruviana. Other than P. cruentata, the two clades that constitute Pyrrhura appear to have radiated and evolved their present mtDNA diversity over short periods during the Plio-Pleistocene.Sistemática Molecular y Patrones de Diversificación en Pyrrhura (Psittacidae), con Énfasis en el Complejo Picta-Leucotis

scholarly journals Phylogenetic Position and Generic Placement of The Socorro Wren (Thryomanes Sissonii)

The Auk ◽  
2005 ◽  
Vol 122 (1) ◽  
pp. 50-56 ◽  
Author(s):  
Juan E. Martínez Gómez ◽  
Brian R. Barber ◽  
A. Townsend Peterson
Keyword(s):  
Mitochondrial Dna ◽  
Dna Sequences ◽  
Species Complex ◽  
Taxonomic Classification ◽  
Phylogenetic Position ◽  
Base Pairs ◽  
House Wren ◽  
Taxonomic History ◽  
Socorro Island ◽  
Nd2 Gene

Abstract Since early in its taxonomic history, placement of the Socorro Wren (Thryomanes sissonii) has been an object of contention. Of particular interest is its current placement in the genus Thryomanes, which makes that genus ditypic and leads to an odd biogeographic scenario for the Socorro Wren's colonization of Socorro Island. We assessed its phylogenetic position by analyzing 516 base pairs of mitochondrial DNA sequences from the ND2 gene of this species and 14 additional wren taxa. Contrary to its present placement, the Socorro Wren is nested phylogenetically within the House Wren species complex, being placed as sister to the clade Troglodytes aedon + T. musculus. The current hypothesis (i.e. sister to Thryomanes bewickii) is strongly invalidated by our analysis. Our analyses indicate that the most appropriate taxonomic classification for the Socorro Wren is Troglodytes sissonii. Posición Filogenética y Ubicación Genérica de Thryomanes sissonii

Workshop no. 6. Structure, function and evolution of kinetoplast DNA

Parasitology ◽  
1981 ◽  
Vol 82 (4) ◽  
pp. 81-93 ◽  
Keyword(s):  
Mitochondrial Dna ◽  
Structure Function ◽  
Network Structure ◽  
The Other ◽  
Kinetoplast Dna ◽  
Base Pairs ◽  
Other Hand

The kinetoplast DNA (kDNA) of kinetoplastidae was the first mitochondrial DNA (mtDNA) to be discovered, and with its unusual network structure, consisting of more than 104catenated DNA circles, it is without equal in nature. Analysis of networks from various genera (reviewed by Borst & Hoeijmakers (1979a) and Englund (1980)) has shown that they always consist of two components: mini-circles and maxi-circles (see Table 1). The mini-circles are the major component and deterraine the size and sliape of networks. They vary in size between 1 and 3 kilo-base pairs (kb = 1000 base pairs (bp)), they are heterogeneous in sequence, their sequence evolves rapidly and their function is not yet known. The maxi-circles, on the other hand, are homogeneous in sequence, their sequence is conserved and they probably represent the counterpart of mtDNA in other organisms.

scholarly journals Mitochondrial DNA Variation, Species Limits, and Rapid Evolution of Plumage Coloration and Size in the Savannah Sparrow

The Condor ◽  
2005 ◽  
Vol 107 (1) ◽  
pp. 21-28 ◽  
Author(s):  
Robert M. Zink ◽  
James D. Rising ◽  
Steve Mockford ◽  
Andrew G. Horn ◽  
Jonathan M. Wright ◽  
...  
Keyword(s):  
Mitochondrial Dna ◽  
Nova Scotia ◽  
San Diego ◽  
Baja California ◽  
Rapid Evolution ◽  
Plumage Coloration ◽  
Phylogeographic Structure ◽  
Species Status ◽  
Passerculus Sandwichensis ◽  
Savannah Sparrows

Abstract We compared sequences from two mitochondrial DNA (mtDNA) genes (ND2, ND3) in Savannah Sparrows (Passerculus sandwichensis; n = 112) sampled from Baja California (five sites), coastal Sonora and the continental range (eight sites). Populations from Baja California, San Diego and Sonora formed a clade within which there was no phylogeographic structure; this clade merits species status (Passerculus rostratus). The other clade, consisting of phenotypically “typical” savannah sparrows, should be classified as P. sandwichensis. Among the typical sparrows, there was no phylogeographic structure, although two major clades were discovered. Representatives of each of the two main clades occurred at most sampling localities, excluding Suisan Bay, California and Sable Island, Nova Scotia, Canada. Haplotypes found on Sable Island, representing the “Ipswich Sparrow,” were not distinctive, thereby failing to support species status for this taxon. On Isla San Benito, a single haplotype was found, which also occurred in other Mexican localities. The results for Sable Island and Isla San Benito show that size and plumage coloration can evolve rapidly. Variación en ADN Mitocondrial, Límites entre Especies y Evolución Rápida de la Coloración del Plumaje y el Tamaño en Passerculus sandwichensis Resumen. En este estudio comparamos secuencias de dos genes mitocondriales (ND2 y ND3) entre individuos de la especie Passerculus sandwichensis (n = 112) muestreados en Baja California (5 sitios), la costa de Sonora y el rango de distribución continental (8 sitios). Las poblaciones de Baja California, San Diego y Sonora formaron un clado, al interior del cual no existió estructura filogeográfica; este clado merece estatus de especie (Passerculus rostratus). El otro clado, conformado por individuos fenotípicamente “típicos”, debe clasificarse como P. sandwichensis. Entre los individuos típicos no existió estructura filogeográfica, aunque se descubrieron dos clados principales. Individuos representativos de cada uno de estos dos clados se encontraron en la mayoría de las localidades, excepto Suisan Bay, California y Sable Island, Nova Scotia. Los haplotipos encontrados en Sable Island, correspondientes al “gorrión de Ipswich” no fueron distintivos, lo que no apoya el estatus de especie para este taxón. En Isla San Benito se encontró un solo halpotipo, el cual también se encontraba en otras localidades mexicanas. Los resultados de Sable Island e Isla San Benito muestran que el tamaño y la coloración del plumaje pueden evolucionar rápidamente.

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