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1.
Zookeys ; 902: 1-15, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33061769

RESUMEN

The genus Artemia Leach, 1819 is a cosmopolitan halophilic crustacean, consisting of bisexual species and obligate parthenogenetic populations. Asia is rich in Artemia biodiversity. More than 530 Artemia sites have been recorded from this area and more than 20 species/subspecies/variety names have been used for them. There exist various problems in the nomenclature, identification, and phylogenetic status of Artemia native to Asia, which are discussed in this paper.

2.
PeerJ ; 8: e8280, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31915579

RESUMEN

Apis mellifera scutellata and Apis mellifera capensis, two native subspecies of western honey bees in the Republic of South Africa (RSA), are important to beekeepers in their native region because beekeepers use these bees for honey production and pollination purposes. Additionally, both bees are important invasive pests outside of their native ranges. Recently, whole mitogenome sequencing and single nucleotide polymorphisms were used to study their genetic diversity. To add to our knowledge of the molecular ecology of both bees, we tested the ability of microsatellites to be used as a tool to discriminate between A.m. capensis and A.m. scutellata. We analyzed the genetic variability and overall population structure of both bee subspecies and hybrids of the two by genotyping individuals collected from RSA (N = 813 bees from 75 apiaries) at 19 microsatellite DNA loci. Overall, populations averaged between 9.2 and 11.3 alleles per locus, with unbiased heterozygosity values ranging from 0.81 to 0.86 per population. Bayesian clustering analyses revealed two distinct evolutionary units, though the results did not match those of earlier morphometric and molecular analyses. This suggests that the microsatellites we tested were not sufficient for subspecies identification purposes, especially for Cape and hybrid bees. Nevertheless, the microsatellite data highlight the considerable genetic diversity within both populations and a larger-than-expected hybridization zone between the natural distributions of A.m. capensis and A.m. scutellata.

3.
PeerJ ; 7: e7190, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31304060

RESUMEN

Urmia Lake, the largest natural habitat of the brine shrimp Artemia urmiana, has progressively desiccated over the last two decades, resulting in a loss of 80% of its surface area and producing thousands of hectares of arid salty land. This ecological crisis has seriously affected the lake's native biodiversity. Artemia urmiana has lost more than 90% of its population during the decade from 1994 (rainy period) to 2004 (drought period) due to salinity increasing to saturation levels (∼300 g/l). We studied the influence of this ecological crisis on the genetic diversity of A. urmiana in Urmia Lake, based on one cyst collections in 1994 and 2004. AMOVA analysis on ISSR data demonstrated a 21% genetic variation and there was a 5.5% reduction of polymorphic loci between samples. PCoA showed that 77.42% and 68.75% of specimens clustered separately in 1994 and 2004, respectively. Our analyses of four marker genes revealed different genetic diversity patterns with a decrease of diversity at ITS1 and an increase for Na+/K+ ATPase. There was no notable difference in genetic variation detected for COI and 16S genes between the two periods. However, they represented distinctly different haplotypes. ITS1 and COI followed a population expansion model, whereas Na+/K+ ATPase and 16S were under demographic equilibrium without selective pressure in the 1994 samples. Neutrality tests confirmed the excess of rare historical and recent mutations present in COI and ITS1 in both samples. It is evident that a short-term ecological disturbance has impacted the genetic diversity and structure of A. urmiana.

4.
Mitochondrial DNA B Resour ; 4(2): 3425-3426, 2019 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-33366023

RESUMEN

The mitochondrial genome of Sinularia maxima was completed using next-generation sequencing (NGS) method. The mitochondrial genome is a circular molecule of 18,730 bp in length. The gene arrangements include 14 protein-coding genes (PCGs), 2 ribosomal RNA genes, and 1 tRNA (tRNA-Met). The base composition is 30.18% A, 16.47% C, 19.35% G, and 33.99% T, with an A + T content of 64.18%. With regard to the phylogenetic analysis, members of genus Sinularia were clustered in different clades.

5.
Mitochondrial DNA B Resour ; 4(2): 3734-3735, 2019 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-33366165

RESUMEN

The complete mitochondrial genome of Sarcophyton trocheliophorum was completed using next-generation sequencing (NGS) method. The mitochondrial genome is a circular molecule of 18,508 bp in length, containing 14 protein-coding genes, two ribosomal RNA genes and one transfer RNA gene (Met-tRNA). The base composition is 30.45% A, 16.03% C, 19.13% G, and 34.40% T, with an A + T content of 64.85%. A phylogenetic analysis of Alcyoniidae showed that genus Sarcophyton had the closest relationship with Sinularia.

6.
Mitochondrial DNA B Resour ; 3(2): 776-777, 2018 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-33474319

RESUMEN

The complete mitochondrial genome of the Asian river pipefish Doryichthys boaja was sequenced. The mitochondrial genome is a circular molecule of 16,439 bp in length, containing 37 mitochondrial genes and a control region. The base composition is 31.03% A, 24.22% C, 14.44% G, and 30.32% T, with an A + T content of 61.35%. All PCGs were initiated by ATG start codon expecting COX1 by GTG. A phylogenetic tree showed that Doryichthys boaja clustered with Microphis brachyurus.

7.
Mitochondrial DNA B Resour ; 3(2): 923-924, 2018 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-33474368

RESUMEN

The complete mitochondrial genome of Solegnathus hardwickii was determined to be 16,519 bp long circular molecule with a typical gene arrangement of vertebrate mitochondrial. The complete mitochondrial genomes were obtained by conventional and long PCR. Tree constructed using maximum likelihood based on protein-coding genes and ribosomal RNAs showed close relationship of S. hardwickii with Hippocampus spp.

8.
Zootaxa ; 4097(2): 294-300, 2016 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-27394547

RESUMEN

The brine shrimp Artemia urmiana, an abundant inhabitant of the hypersaline Urmia Lake in northwestern Iran, has recently been described from Lake Koyashskoe, also a shallow hypersaline lake that is located on the Black Sea coast of the Crimean Peninsula (Ukraine). This discovery has questioned the endemicity of A. urmiana in Urmia Lake and has also brought into question the biogeographical origin of this species. In the present study, we combined recent genetic divergence data (mtDNA-COI) with palaeoecological evidence to address the biogeographical origin of A. urmiana. Calibration of the molecular clock of the COI region was set by assigning the age of the micro-crustacean Daphnia pulex minimally at 145 Mya. The divergence age of A. urmiana in Urmia Lake dates back to 383,000 years, whereas Ukrainian Artemia reflects a very young populations that diverged about 196,000 years ago. Palaeoecological evidence suggests that the age of the major habitat of A. urmiana i.e. Urmia Lake goes back to the Tertiary Period while the Ukranian habitats of the species are very young, by virtue of geological features of the Holocene age. We conclude that the biogeographical origin of A. urmiana is outside of Europe and the current state of knowledge strongly suggests that Urmia Lake has been the major source of its expansion into its modern habitats in Europe.


Asunto(s)
Artemia/clasificación , Distribución Animal , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Artemia/anatomía & histología , Artemia/genética , Artemia/crecimiento & desarrollo , Tamaño Corporal , Ecosistema , Femenino , Irán , Lagos/química , Masculino , Tamaño de los Órganos , Filogenia
9.
Microsc Res Tech ; 79(4): 258-66, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26777727

RESUMEN

Parthenogenetic Artemia from seven Chinese locations with different elevations and various ploidies are characterized by phenotypic and morphometric analyses. Our findings show that the studied populations exhibit dissimilar patterns of ovisac. Four phenotypic patterns of furca are qualified and one of them is shared among di-, tetra- and pentaploid Artemia. Results of discriminant analysis based on morphometric data reveal that tetra- and pentaploid populations are grouped together, but the Aqqikkol Lake population is clearly differentiated. Previous hypothesis/conclusion that polyploid Artemia are larger than diploids is only partly supported by the present results, which show that pentaploid and tetraploid populations are larger than the mostly diploid populations in terms of the total length, but the body size of the Aibi Lake triploids has not significant difference with the sympatric diploids and the mostly diploid Aqqikkol population that inhabit in very high altitude has the largest body size among all parthenogenetic populations. The founding confirms that body size of Artemia is following with Bergmann's rule.


Asunto(s)
Artemia/anatomía & histología , Artemia/genética , Ploidias , Estructuras Animales/anatomía & histología , Estructuras Animales/crecimiento & desarrollo , Animales , Artemia/clasificación , Artemia/crecimiento & desarrollo , Tamaño Corporal , China , Tamaño de los Órganos
10.
Microsc Res Tech ; 77(12): 1005-14, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25158082

RESUMEN

The cysts of nine Chinese populations of parthenogenetic Artemia were studied by scanning electron microscope. In the 270 cysts examined, 15 different morphological patterns were recognized with most of them not recorded in previous studies and the "tubercled shell surface" being the most common pattern. Results also displayed high intrapopulation variability, with the maximum of 11 patterns (in 30 cysts) recorded from the Barkol population. No positive correlation between the diversity of cyst shell patterns and ploidy compositions was found. Principal components analysis suggests higher similarity among coastal populations than among inland populations, which may be attributed to the identity of physicochemical conditions among coastal salterns and dissimilarity among inland saline lakes.


Asunto(s)
Artemia/ultraestructura , Óvulo/ultraestructura , Animales , Artemia/genética , Artemia/fisiología , China , Microscopía Electrónica de Rastreo , Ploidias , Análisis de Componente Principal , Reproducción
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