Biosystematic study of the Egyptian Datura stramonium (Solanaceae)

Phytotaxa ◽  
2019 ◽  
Vol 408 (3) ◽  
pp. 178-194
Author(s):  
RANIA A. HASSAN ◽  
WAFAA M. AMER
Keyword(s):  
Datura Stramonium ◽  
Distinct Species ◽  
Asymmetry Index ◽  
Pollen Characters ◽  
The World ◽  
Cytogenetic Studies ◽  
Morphological Differences ◽  
Intrachromosomal Asymmetry ◽  
Stem Colour ◽  
Genomic Length

Datura stramonium (Solanaceae) is an annual weed found in most temperate and subtropical regions of the world. The taxonomic identity of this species is still under debate since Linnaeus first published the name. Early on, many varieties and forms were recognized. In Egypt, D. stramonium presents in two forms: the white-flowered ‘stramonium’ form and violet-flowered ‘tatula’ form. Some authors treated D. stramonium and D. tatula as two distinct species, while others included D. tatula within D. stramonium as either a variety or forma. The present study aimed to elucidate the taxonomic identity of both the white ‘stramonium’ and the violet ‘tatula’ forms based on morphological, palynological and cytogenetic studies extended to karyotyping. A taxonomic study of these forms was carried out using 75 morphological and pollen characters. Significant morphological differences were observed; the most important ones were flower and stem colour, in addition to flower and fruit dimensions. The anatomical examination of juvenile-fruit in acropetal transverse sections, revealed the gradual displacement of parietal placentation at the fruit base to axile at the fruit apex. Pollen of both forms showed no significant differences. Cytogenetic results revealed the presence of a diploid chromosome number (2n=2x=24) in both forms, with minor aneuploidy in the ‘tatula’ form. According to the karyotyping, notable differences were found between the two studied forms, including the centromeric index, total genomic length, and intrachromosomal asymmetry index. Morphological and cytogenetic data revealed that the two forms are different enough to be treated taxonomically as two distinct varieties, namely D. stramonium var. stramonium and D. stramonium var. tatula.

A scanning electron microscopic study of the eggs of Culicoides variipennis (Diptera: Ceratopogonidae)

1987 ◽  
Vol 45 ◽  
pp. 884-885 ◽  
Author(s):  
R. A. Nunamaker ◽  
C. E. Nunamaker ◽  
B. C. Wick
Keyword(s):  
Distinct Species ◽  
Hemorrhagic Disease ◽  
Insect Vector ◽  
Electron Microscopic ◽  
Important Species ◽  
Scanning Electron Microscopic Study ◽  
Laboratory Colony ◽  
Culicoides Variipennis ◽  
Morphological Differences ◽  
Scanning Electron

Culicoides variipennis (Coquillett) is probably the most economically important species of biting midge in the U.S. due to its involvement in the transmission of bluetongue (BT) disease of sheep, cattle and ruminant wildlife, and epizootic hemorrhagic disease (EHD) of deer. Proposals have been made to recognize the eastern and western populations of this insect vector as distinct species. Others recommend use of the term “variipennis complex” until such time that the necessary biosystematic studies have been made to determine the genetic nature and/or minute morphological differences within the population structure over the entire geographic range of the species. Increasingly, students of ootaxonomy are relying on scanning electron microscopy (SEM) to assess chorionic features. This study was undertaken to provide comparative chorionic data for the C. variipennis complex.Culicoides variipennis eggs were collected from a laboratory colony maintained in Laramie, Wyoming.

A reassessment of Dioon merolae (Zamiaceae) leads to the description of Dioon salas-moralesae, a new cycad species from Southeastern Oaxaca, Mexico

Phytotaxa ◽  
2021 ◽  
Vol 528 (2) ◽  
pp. 93-110
Author(s):  
JOSÉ SAID GUTIÉRREZ-ORTEGA ◽  
MIGUEL ANGEL PÉREZ-FARRERA ◽  
JEFFREY CHEMNICK ◽  
TIMOTHY J. GREGORY
Keyword(s):  
New Species ◽  
Morphological Variation ◽  
Related Species ◽  
Statistical Tests ◽  
Distinct Species ◽  
Closely Related Species ◽  
Morphometric Variation ◽  
Isthmus Of Tehuantepec ◽  
Morphological Differences ◽  
Recent Evaluation

The cycad genus Dioon comprises 17 species from Mexico and Honduras, all of them delimited based on their morphological variation and geographic distribution. A recent evaluation of the biological variation among Dioon populations from Oaxaca and Chiapas, Mexico, demonstrated that the concept of the species Dioon merolae actually consists of three lineages that should be recognized as different taxa. One lineage was already described as Dioon oaxacensis, leaving the concept of Dioon merolae comprising two lineages distributed on both sides of the Isthmus of Tehuantepec. However, there are conspicuous morphological differences between these two lineages. Here, we tested whether such a differentiation within the concept of Dioon merolae merits the differentiation of two different taxa. We evaluated the qualitative and morphometric variation among populations belonging to the Dioon merolae lineages, and compared it with the closely related species Dioon oaxacensis. Morphological observations and statistical tests demonstrated that the populations of southeastern Oaxaca, traditionally considered as part of Dioon merolae, represent a distinct species that we described as Dioon salas-moralesae. Identifying the diagnostic characters of this new species helps enable an understanding of the criteria that should be considered to delineate the boundaries between other cycad species.

scholarly journals Pollen characters as taxonomic evidence in some species of Dipsacaceae from Iran

2017 ◽  
Vol 24 (2) ◽  
pp. 129-136 ◽  
Author(s):  
Ebadi-Nahari Mostafa ◽  
Nikzat-Siahkolaee Sedigheh ◽  
Eftekharian Rosa
Keyword(s):  
Pollen Morphology ◽  
Pollen Grains ◽  
Pollen Grain ◽  
Pollen Type ◽  
Upgma Tree ◽  
Pollen Characters ◽  
Exine Ornamentation ◽  
The Family ◽  
The World ◽  
Plant Taxon

Pollen morphology of nine species representing four genera: Cephalaria Schrad, Dipsacus L., Pterocephalus Vaill. and Scabiosa L. of the family Dipsacaceae in Iran has been investigated by means of scanning electron microscopy (SEM). The results showed that pollen grains were triporate and tricolpate. The pollen type of Scabiosa rotata Bieb. (tri- and tetraporate) is the first report in the world. The sizes of pollen grains fall into the classification group magna (pollen grain diameter 50–100 μm). Pollen shapes vary from preoblate to prolate and their polar views were triangulate and lobate. The exine ornamentation varies from gemmate in S. rotata to spinulate in the rest studied species. Species of Scabiosa have been dispersed in UPGMA tree that this confirmed the previous studies about taxonomic problems and species complexity in this genus. These results show the transfer of the some Scabisoa species to Lomelosia Raf. based on palynological characters. Pollen morphology of the family is helpful at the generic and specific level.Bangladesh J. Plant Taxon. 24(2): 129–136, 2017 (December)

Goodyera malipoensis (Cranichideae, Orchidaceae), a new species from China: Evidence from morphological and molecular analyses

Phytotaxa ◽  
2014 ◽  
Vol 186 (1) ◽  
pp. 51 ◽  
Author(s):  
Qiu-Xiang Chen ◽  
Gui-Zhen Chen ◽  
Ming-He Li ◽  
Shi-Pin Chen
Keyword(s):  
New Species ◽  
Sequence Data ◽  
Detailed Comparison ◽  
Distinct Species ◽  
Molecular Study ◽  
Its Sequence ◽  
Orchid Species ◽  
Molecular Analyses ◽  
Morphological Differences ◽  
A New Species

In this study, we describe a new orchid species, Goodyera malipoensis, from Yunnan, China. We have performed morphological and molecular analyses on this new species. A detailed comparison between the newly discovered orchid and other members of Goodyera was conducted. The new plant is characterized by having a dense brownish green pubescence on the peduncle. Its ovate-lanceolate petal is unique in Goodyera genus. The hypochile is deeply concave-saccate, and inside there are two papillose rows on each side. These features distinguish the new orchid from all other known species of Goodyera. The molecular study based on nuclear ribosomal ITS sequence data and morphological differences support G. malipoensis as a distinct species.

Morphological and molecular characterization of two species of Gelidium (Gelidiales, Rhodophyta) from Mexico: G. nayaritense sp. nov. and the new record of G. sanyaense

Phytotaxa ◽  
2021 ◽  
Vol 527 (3) ◽  
pp. 161-176
Author(s):  
NATALY QUIROZ-GONZÁLEZ ◽  
MA. EDITH PONCE-MÁRQUEZ ◽  
NORMA LÓPEZ-GÓMEZ ◽  
DENÍ RODRÍGUEZ
Keyword(s):  
Gulf Of California ◽  
Phylogenetic Analyses ◽  
Distinct Species ◽  
Tropical Region ◽  
Mexican Pacific ◽  
Molecular Approaches ◽  
Diagnostic Characteristics ◽  
Morphological Differences ◽  
First Time

Gelidium pusillum is a species reported from the northern Gulf of California to the tropical region of the Mexican Pacific, but there is wide morphological variation among populations. The objective of this research was to evaluate of the Mexican species using morphological and molecular approaches, with the markers rbcL and COI-5P. This study examined 12 samples from four sites in the Mexican tropical Pacific. Phylogenetic analyses resolved these specimens within two clades separated from the topotype material of G. pusillum. The main morphological differences with other Mexican and phylogenetic closely related species were size, branching pattern, branching order, distribution of internal rhizoidal filaments, and shape of the tetrasporangial sori. The sequence divergences between these clades and the morphological differences support their representing distinct species so that Gelidium nayaritense sp. nov. is proposed for tropical specimens of the Mexican Pacific, whose diagnostic characteristics are the little or absent branching, its small size, as well as the presence of internal rhizoidal filaments concentrated in the subcortex, further G. sanyaense is register for first time from Mexico and Eastern Pacific.

The genus Waltheria in southern Africa

Bothalia ◽  
1981 ◽  
Vol 13 (3/4) ◽  
pp. 275-276 ◽  
Author(s):  
I. C. Verdoorn
Keyword(s):  
West Africa ◽  
Southern Africa ◽  
Distinct Species ◽  
Wide Distribution ◽  
Herbarium Specimens ◽  
South West ◽  
The World ◽  
Northern Cape ◽  
South West Africa ◽  
The Tropics

Waltheria indica L., the only species of Waltheria represented in southern Africa, is revised. This species, which occurs throughout the tropics and substropics of the world, is found abundantly in the northern Cape, Swaziland, northern Natal, Transvaal and northwards through South West Africa/Namibia and Botswana. Thoughout its wide distribution the species is uniform. A scrutiny o f herbarium specimens revealed that what appeared as a distinct species or subspecies was without doubt an abnormality, probably caused by insect injury.

scholarly journals Molecular and Serological Characterization of Iris Yellow Spot Virus, a New and Distinct Tospovirus Species

1998 ◽  
Vol 88 (12) ◽  
pp. 1276-1282 ◽  
Author(s):  
I. Cortês ◽  
I. C. Livieratos ◽  
A. Derks ◽  
D. Peters ◽  
R. Kormelink
Keyword(s):  
Datura Stramonium ◽  
Distinct Species ◽  
Iris Yellow Spot Virus ◽  
Yellow Spot ◽  
Spot Virus ◽  
Serological Characterization ◽  
Tospovirus Species ◽  
Experimental Host Range

A new tospovirus was identified in iris cultivations in the Netherlands. Both serological comparisons and sequence determination of the S RNA demonstrate that this virus represents a new and distinct species, belonging to a separate serogroup, and for which the name iris yellow spot virus (IYSV) is proposed. The disease symptoms on iris are characterized by yellow spots on the leaves. Its experimental host range is very narrow and, in addition to iris, only includes Nicotiana benthamiana and Datura stramonium. The nucleoprotein of IYSV shows only 30 to 44% sequence identity with those of other tospoviruses identified so far; the highest homology being found with the tospovirus species of serogroup IV.

Étude caryologique de trois espèces d’Hypochoeris originaires d'Argentine : H. chillensis, H. microcephala var. albiflora et H. megapotamica

1994 ◽  
Vol 72 (10) ◽  
pp. 1496-1502 ◽  
Author(s):  
S. Siljak-Yakovlev ◽  
A. Bartoli ◽  
G. Roitman ◽  
N. Barghi ◽  
C. Mugnier
Keyword(s):  
Chromosome Number ◽  
Related Species ◽  
Secondary Constriction ◽  
Nucleolar Organizer ◽  
Asymmetry Index ◽  
Evolutionary Trend ◽  
Closely Related Species ◽  
Nucleolar Organizers ◽  
Morphological Differences ◽  
Secondary Constrictions

Three Hypochoeris species from Argentina with the same chromosome number (x = 4) and similar karyotypes (typically bimodal) show significant ecological and morphological differences. Comparative cytogenetic analysis was done for these taxa, producing karyotypes with correlated idiograms. The number of secondary constrictions and nucleolar organizers varied. The results from this study are discussed in terms of the mechanisms of microevolution within this group of closely related species, and in terms of the evolutionary trend in the genus and in the tribe Cichorieae. Key words: Hypochoeris, Cichorieae, bimodal karyotype, secondary constriction, nucleolar organizer, asymmetry index.

On the European species of Eubranchus [Mollusca Opisthobranchia]

1969 ◽  
Vol 49 (4) ◽  
pp. 879-912 ◽  
Author(s):  
Malcolm Edmunds ◽  
Annetrudi Kress
Keyword(s):  
Distinct Species ◽  
Junior Synonym ◽  
Reproductive Systems ◽  
European Species ◽  
Ecological Characteristics ◽  
The World ◽  
The Mediterranean

On the basis of extensive material from Plymouth an attempt has been made to determine the specific limits of the European species of the eolid genus Eubranchus Forbes. From a study of the living animals, jaws, radulae and reproductive systems, it is concluded that five species can be recognized as occurring commonly in Britain, Eubranchus tricolor Forbes (=Galvina viridula Bergh), E. farrani (Alder & Hancock), E. pallidus (Alder & Hancock), E. cingulatus (Alder & Hancock) and E. exiguus (Alder & Hancock). These species are all variable in coloration, but they can nevertheless be easily distinguished by coloration as well as by morphological and ecological characteristics. A further species, E. doriae (Trinchese) from the Mediterranean, was also examined and appears to be distinct. No material of Eubranchus rupiurn (Moller) and E. vittatus (Alder & Hancock) was available for examination, but these are provisionally maintained as distinct species. The European species of Eubranchus are compared with species from other parts of the world in an attempt to decide how many genera should be recognized. It is concluded that the armature of the penis and the liver branching do not form good generic characters, and that consequently Capellinia is to be regarded as a junior synonym of Eubranchus.

Differentiation in Coregonus zenithicus in Lake Superior

1980 ◽  
Vol 37 (12) ◽  
pp. 2228-2235 ◽  
Author(s):  
Thomas N. Todd ◽  
Gerald R. Smith
Keyword(s):  
Endangered Species ◽  
Great Lakes ◽  
Lake Superior ◽  
Distinct Species ◽  
Multivariate Morphometrics ◽  
Geographic Isolation ◽  
Allometric Growth ◽  
Spawning Time ◽  
Morphological Differences ◽  
Species Taxonomy

Morphological variation in Coregonus zenithicus has long plagued biologists working on Lake Superior ciscoes. Some of this variation is due to allometric growth; earlier workers incorrectly recognized large C. zenithicus as a distinct species, C. nigripinnis cyanopterus. Coregonus reighardi dymondi is a variant of C. zenithicus in northern bays of Lake Superior and Lake Nipigon. The morphological differences between members of spring and fall spawning populations of C. zenithicus in Lake Superior are no greater than those between geographically separate populations. We conclude that spawning time and geographic isolation act similarly in effecting differentiation of coregonine populations, and that populations with different spawning times do not necessarily represent different species.Key words: Coregonus zenithicus, cisco, Great Lakes, multivariate morphometrics, endangered species, taxonomy

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