A combination of molecular and morphological approaches resolves species in the taxonomically difficult genus Procladius Skuse (Diptera: Chironomidae) despite high intra-specific morphological variation

2011 ◽  
Vol 101 (5) ◽  
pp. 505-519 ◽  
Author(s):  
M.E. Carew ◽  
S.E. Marshall ◽  
A.A. Hoffmann
Keyword(s):  
Cryptic Species ◽  
Morphological Variation ◽  
Nuclear Gene ◽  
Pupal Stage ◽  
Mitochondrial Genes ◽  
Pollution Monitoring ◽  
Species Variation ◽  
Molecular Approaches ◽  
Difficult Genus ◽  
Morphological Criteria

AbstractMolecular approaches for identifying aquatic macroinvertebrate species are increasingly being used but there is ongoing debate about the number of DNA markers needed to differentiate species accurately. Here, we use two mitochondrial genes (cytochrome oxidase I, cytochrome b) and a nuclear gene (carbamoylphosphate synthetase) to differentiate species variation within the taxonomically challenging chironomid genus Procladius from southern Australia, a genus which is important for pollution monitoring. The mitochondrial genes indicated cryptic species that were subsequently linked to morphological variation at the larval and pupal stage. Two species previously described based on morphological criteria were linked to molecular markers, and there was evidence for additional cryptic species. Each genetic marker provided different information, highlighting the importance of considering multiple genes when dissecting taxonomically difficult groups, particularly those used in pollution monitoring.

scholarly journals Notes on the leaf insects of the genus Phyllium of Sumatra and Java, Indonesia, including the description of two new species with purple coxae (Phasmatodea, Phylliidae)

ZooKeys ◽  
2020 ◽  
Vol 913 ◽  
pp. 89-126 ◽  
Author(s):  
Royce T. Cumming ◽  
Sarah Bank ◽  
Stephane Le Tirant ◽  
Sven Bradler
Keyword(s):  
Cryptic Species ◽  
Morphological Difference ◽  
Nuclear Gene ◽  
Molecular Data ◽  
Mitochondrial Genes ◽  
Peninsular Malaysia ◽  
The Other ◽  
Two New Species ◽  
First Time ◽  
Two Populations

Within the last two years, the leaf insects of the genus Phyllium of both the islands of Java and Sumatra have been reviewed extensively based on morphological observations. However, cryptic species which cannot be differentiated morphologically may be present among the various populations. Since it has frequently been demonstrated that analyses based on molecular data can bring clarity in such cases, we conducted a phylogenetic analysis based on three genes (nuclear gene 28S and mitochondrial genes COI and 16S) from the Phyllium species of these islands. The results show distinct molecular divergence for several populations and suggest the presence of two new cryptic species, morphologically inseparable from Phyllium hausleithneri Brock, 1999. From Sumatra, the population originally thought to be a range expansion for Phyllium hausleithneri, is now here described as Phyllium nisussp. nov., with the only consistent morphological difference being the color of the eggs between the two populations (dark brown in P. hausleithneri and tan in P. nisussp. nov.). Further, an additional population with purple coxae from Java was morphologically examined and found to have no consistent features to separate it morphologically from the other purple coxae species. This cryptic species from Java was however shown to be molecularly distinct from the other purple coxae populations from Sumatra and Peninsular Malaysia and is here described as Phyllium gardabagusisp. nov. In addition, Phyllium giganteum is here officially reported from Java for the first time based on both historic and modern records of male specimens.

scholarly journals Nuclear Gene Dosage Effects Upon the Expression of Maize Mitochondrial Genes

Genetics ◽  
2001 ◽  
Vol 157 (4) ◽  
pp. 1711-1721
Author(s):  
Donald L Auger ◽  
Kathleen J Newton ◽  
James A Birchler
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Gene Dosage ◽  
Nuclear Gene ◽  
Eukaryotic Cell ◽  
Mitochondrial Genes ◽  
Northern Analysis ◽  
Α Subunit ◽  
Dosage Effects ◽  
A Genome

Abstract Each mitochondrion possesses a genome that encodes some of its own components. The nucleus encodes most of the mitochondrial proteins, including the polymerases and factors that regulate the expression of mitochondrial genes. Little is known about the number or location of these nuclear factors. B-A translocations were used to create dosage series for 14 different chromosome arms in maize plants with normal cytoplasm. The presence of one or more regulatory factors on a chromosome arm was indicated when variation of its dosage resulted in the alteration in the amount of a mitochondrial transcript. We used quantitative Northern analysis to assay the transcript levels of three mitochondrially encoded components of the cytochrome c oxidase complex (cox1, cox2, and cox3). Data for a nuclearly encoded component (cox5b) and for two mitochondrial genes that are unrelated to cytochrome c oxidase, ATP synthase α-subunit and 18S rRNA, were also determined. Two tissues, embryo and endosperm, were compared and most effects were found to be tissue specific. Significantly, the array of dosage effects upon mitochondrial genes was similar to what had been previously found for nuclear genes. These results support the concept that although mitochondrial genes are prokaryotic in origin, their regulation has been extensively integrated into the eukaryotic cell.

Morphological and molecular identification of Octopoda (Mollusca: Cephalopoda) paralarvae from the southern Gulf of Mexico

2021 ◽  
Author(s):  
Mariana L Santana-Cisneros ◽  
Rossanna Rodríguez-Canul ◽  
Jesús Alejandro Zamora-Briseño ◽  
Monica Améndola-Pimenta ◽  
Roxana De Silva-Dávila ◽  
...  
Keyword(s):  
Gulf Of Mexico ◽  
First Record ◽  
Coi Gene ◽  
Octopus Vulgaris ◽  
Type I ◽  
Molecular Sequences ◽  
Molecular Approaches ◽  
Morphological Criteria ◽  
Southern Gulf Of Mexico ◽  
Genetic Sequences

Paralarvae (PL) are crucial to understanding the life cycle and population dynamics of cephalopods. Misidentification of species with similar morphology is a problem that hampers understanding of cephalopod composition and distribution. In this study, we used morphological and molecular approaches to carry out a comprehensive identification of Octopoda PL that inhabit two main areas (Tamaulipas and Yucatán) in the southern Gulf of Mexico (GoM). A total of 189 paralarvae were identified using morphological criteria. Of these, 52 PL were analyzed molecularly by sequencing the mitochondrial cytochrome c oxidase subunit I (COI) gene. We identified four species and five morphotypes. The molecular tools corroborated three of four species, while the molecular sequences of three out of four morphotypes indicated that they belong to three different species. All the genetic sequences had high similarities (99.3%–100%) with previous records. One species and one morphotype could not be sequenced because of unsatisfactory fixation; one morphotype remained as such after the molecular analysis. An identification tree was constructed for the species identified with the molecular approach. The species found off the Yucatán platform were Octopus vulgaris Type I, Octopus americanus, Macrotritopus defilippi, Amphioctopus burryi, A. cf. burryi, Octopus sp., and Callistoctopus furvus. The species identified off the Tamaulipas coast were Octopus insularis and M. defilippi. Paralarvae of O. vulgaris Type I and M. defilippi were the most abundant during 2016–2017. This study provides the first record of Octopoda PL in the southern GoM, including morphological descriptions and molecular sequences of the analyzed taxa.

Mitochondrial biogenesis in striated muscles: rapid induction of citrate synthase mRNA by nerve stimulation

1991 ◽  
Vol 260 (2) ◽  
pp. C266-C270 ◽  
Author(s):  
B. H. Annex ◽  
W. E. Kraus ◽  
G. L. Dohm ◽  
R. S. Williams
Keyword(s):  
Mitochondrial Biogenesis ◽  
Nerve Stimulation ◽  
Time Course ◽  
Citrate Synthase ◽  
Contractile Activity ◽  
Cdna Probe ◽  
Nuclear Gene ◽  
Mitochondrial Genes ◽  
Adult Rabbit ◽  
Mitochondrial Rna

Tonic contractile activity induces mitochondrial biogenesis in mammalian skeletal muscles, necessitating regulation of both nuclear and mitochondrial genes encoding mitochondrial proteins. In this study we compared the time course of induction of citrate synthase (CS) mRNA, a nuclear gene product, to that of genes encoded by mitochondrial DNA during the adaptive response to indirect nerve stimulation in tibialis anterior muscles of adult rabbits. A CS cDNA probe was prepared from a rabbit heart cDNA library by the polymerase chain reaction using synthetic oligonucleotide primers based on the published sequence of the porcine gene. This cDNA probe hybridized to a single band on Northern blots of total or polyadenylated RNA from adult rabbit tissues. Nerve stimulation for 3 days increased the abundance of CS mRNA relative to total cellular RNA by 2.3 +/- 0.2-fold (mean +/- SE, n = 8; P less than 0.01). In contrast, CS enzyme activity and mitochondrial RNA transcripts were not significantly increased at this time point. However, when nerve stimulation was continued for 21 days, the increases in CS mRNA and mitochondrial RNAs were similar. These results support the hypothesis that genetic signaling mechanisms triggered by neural input are sensed initially within the nucleus and that expression of mitochondrial genes is regulated as a secondary event.

scholarly journals Botrytis pseudocinerea, a New Cryptic Species Causing Gray Mold in French Vineyards in Sympatry with Botrytis cinerea

2011 ◽  
Vol 101 (12) ◽  
pp. 1433-1445 ◽  
Author(s):  
Anne-Sophie Walker ◽  
Angélique Gautier ◽  
Johann Confais ◽  
Daniel Martinho ◽  
Muriel Viaud ◽  
...  
Keyword(s):  
New Species ◽  
Cryptic Species ◽  
Botrytis Cinerea ◽  
Germination Rate ◽  
Gray Mold ◽  
Temperature Adaptation ◽  
Morphological Criteria ◽  
Ecological Criteria ◽  
High Level

Botrytis cinerea is a major crop pathogen infesting >220 hosts worldwide. A cryptic species has been identified in some French populations but the new species, B. pseudocinerea, has not been fully delimited and established. The aim of this study was to distinguish between the two species, using phylogenetic, biological, morphological, and ecological criteria. Multiple gene genealogies confirmed that the two species belonged to different, well-supported phylogenetic clades. None of the morphological criteria tested (spore size, germination rate, or mycelial growth) was able to discriminate between these two species. Sexual crosses between individuals from the same species and different species were carried out. Only crosses between individuals from the same species were successful. Moreover, population genetics analysis revealed a high level of diversity within each species and a lack of gene flow between them. Finally, a population survey over time showed that B. cinerea was the predominant species but that B. pseudocinerea was more abundant in spring, on floral debris. This observation could not be explained by temperature adaptation in tests carried out in vitro or by aggressiveness on tomato or bean leaves. This study clearly establishes that B. cinerea and B. pseudocinerea constitute a complex of two cryptic species living in sympatry on several hosts, including grapevine and blackberry. We propose several biological or molecular tools for unambiguous differentiation between the two species. B. pseudocinerea probably makes a negligible contribution to gray mold epidemics on grapevine. This new species has been deposited in the MycoBank international database.

Mitochondrial genes and genomes support a cryptic species of tapeworm within Taenia taeniaeformis

Acta Tropica ◽  
2012 ◽  
Vol 123 (3) ◽  
pp. 154-163 ◽  
Author(s):  
Wanzhong Jia ◽  
Hongbin Yan ◽  
Zhongzi Lou ◽  
Xingwei Ni ◽  
Viktor Dyachenko ◽  
...  
Keyword(s):  
Cryptic Species ◽  
Mitochondrial Genes ◽  
Taenia Taeniaeformis

Integrating DNA barcodes and morphology for species delimitation in theCorynoneuragroup (Diptera: Chironomidae: Orthocladiinae)

2013 ◽  
Vol 104 (1) ◽  
pp. 65-78 ◽  
Author(s):  
F.L. Silva ◽  
S. Wiedenbrug
Keyword(s):  
Dna Markers ◽  
Species Delimitation ◽  
Pupal Stage ◽  
Coi Gene ◽  
Morphological Divergence ◽  
Dna Barcodes ◽  
Morphological Criteria ◽  
Species Groups ◽  
Excellent Tool ◽  
Eleven Species

AbstractIn this study, we use DNA barcodes for species delimitation to solve taxonomic conflicts in 86 specimens of 14 species belonging to theCorynoneuragroup (Diptera: Chironomidae: Orthocladiinae), from the Atlantic Forest, Brazil. Molecular analysis of cytochrome c-oxidase subunit I (COI) gene sequences supported 14 cohesive species groups, of which two similar groups were subsequently associated with morphological variation at the pupal stage. Eleven species previously described based on morphological criteria were linked to DNA markers. Furthermore, there is the possibility that there may be cryptic species within theCorynoneuragroup, since one group of species presented internal grouping, although no morphological divergence was observed. Our results support DNA-barcoding as an excellent tool for species delimitation in groups where taxonomy by means of morphology is difficult or even impossible.

scholarly journals The "Crustacean Seas" — an evolutionary perspective on the Ponto–Caspian peracarids

2005 ◽  
Vol 62 (3) ◽  
pp. 505-517 ◽  
Author(s):  
Melania EA Cristescu ◽  
Paul DN Hebert
Keyword(s):  
Ribosomal Rna ◽  
Adaptive Radiation ◽  
Nuclear Gene ◽  
Taxonomic Status ◽  
Mitochondrial Genes ◽  
Evolutionary Perspective ◽  
Intraspecific Divergence ◽  
Geographic Structure ◽  
Colonization Event ◽  
History Of

A spectacular adaptive radiation of crustaceans has occurred in the Black, Caspian, and Aral seas. This study tests several evolutionary scenarios based on the extent of genetic differentiation and the phylogenetic relationships among endemic mysids and gammarid amphipods from the Black and Caspian seas. Molecular phylogenies for these taxa were based on two mitochondrial genes: cytochrome c oxidase subunit I and the large ribosomal RNA subunit (16S), and one nuclear gene, the large ribosomal RNA subunit (28S). The results support the monophyly of the Ponto–Caspian gammarids (genera Dikerogammarus, Echinogammarus, Obesogammarus, and Pontogammarus), suggesting their origin from one colonization event. By contrast, several colonization events preceded the radiation of the Ponto–Caspian mysids (genera Limnomysis and Paramysis). Levels of intraspecific divergence were variable, with mysids showing either no geographic structure or deep genetic splits reflecting a long history of reproductive isolation between populations in marine settings and those in fresh waters. These findings suggest that the diversity of the Ponto–Caspian crustaceans has been underestimated and that species regarded as euryhaline are often composed of distinct evolutionary groups whose taxonomic status should be reevaluated.

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