The taxonomy and distribution in eastern Canada of Polygonum arenastrum (4x = 40) and P. monspeliense (6x = 60), introduced members of the P. aviculare complex

1981 ◽  
Vol 59 (12) ◽  
pp. 2744-2751 ◽  
Author(s):  
J. McNeill
Keyword(s):  
Chromosome Number ◽  
Single Species ◽  
Sensu Stricto ◽  
The Other ◽  
Eastern Canada ◽  
Uniform Size ◽  
Chromosome Races ◽  
Morphological Studies ◽  
Distinguishing Features ◽  
Polygonum Arenastrum

The introduced nonmaritime knotweeds have generally been regarded in North America as comprising a single species called P. aviculare L. In recent years cytological and morphological studies have suggested that at least two chromosome races are present and that certain morphological features are correlated with chromosome number. There have been, however, discrepancies in the reports of the distribution and relative abundance of the two races. Studies of the morphology and cytology of introduced knotweeds in eastern Canada confirm the existence of two groups that are recognizable at species rank, and establish that the most common knotweeds in open habitats, e. g., along roadsides and sidewalks, are tetraploid plants distinguishable from their hexaploid relatives by the relatively uniform size of their leaves, the short and narrow free portion of the perianth segments, and by one side of the fruit being very much narrower than the other two. These plants are referable to P. arenastrum Boreau. This species is compared with the heterophyllous hexaploid, usually called P. aviculare sensu stricto, or, if that is considered a nomen ambiguum, P. monspeliense Pers. A table of distinguishing features, illustrations of the two species, and maps of their distribution in eastern Canada are provided.

Recherches sur les Alaria (Phaeophyceae) de l'est canadien. I. Nombres chromosomiques et identité des Alaria de l'estuaire du St-Laurent

1974 ◽  
Vol 52 (4) ◽  
pp. 691-694 ◽  
Author(s):  
M.-J. Feller-Demalsy ◽  
P. Demalsy
Keyword(s):  
Chromosome Number ◽  
Single Species ◽  
Chromosome Counts ◽  
Eastern Canada ◽  
Lawrence Estuary ◽  
Haploid Chromosome Number ◽  
Biosystematic Study ◽  
Alaria Esculenta ◽  
St Lawrence Estuary

Chromosome counts in gametophytes and sporophylls of Alaria collected in the St. Lawrence Estuary show that all the specimens of this genus in eastern Canada may not belong to the single species A. esculenta Greville. Indeed, the haploid chromosome number (n) found in these algae is equal to half of the number attributed in the literature to Alaria esculenta from the British coasts. Three hypotheses for the interpretation of these observations are considered. The solution of the problem of the identity of Alaria can only be hoped for from their global, morphological, and biosystematic study.

scholarly journals First records of giant pill-millipedes from Laos (Diplopoda, Sphaerotheriida, Zephroniidae)

Zootaxa ◽  
2019 ◽  
Vol 4563 (2) ◽  
pp. 201 ◽  
Author(s):  
THOMAS WESENER
Keyword(s):  
Molecular Analysis ◽  
Single Species ◽  
Sensu Stricto ◽  
The Other ◽  
Dna Barcodes ◽  
Molecular Barcoding ◽  
Determination Key ◽  
By Catch

Before this study, giant pill-millipedes (order Sphaerotheriida) were unknown from Laos despite their presence in all surrounding countries. As by-catch from collections by arachnologists, 31 specimens of Sphaerotheriida from Laos became available for study. The sample included 14 species. Three species were only represented by females, which are described but cannot be named. Of the remaining 11 species, a single species belongs to the genus Zephronia Gray, 1832: Z. laotica n. sp.; and the other ten belong to the genus Sphaerobelum Verhoeff, 1924: S. bolavensis n. sp., S. phouloei n. sp., S. denticulatum n. sp., S. spinatum n. sp., S. lachneeis n. sp., S. peterjaegeri n. sp., S. nigrum n. sp., S. splendidum n. sp., S. laoticum n. sp., and S. schwendingeri n. sp. This more than doubles the known diversity of Sphaerobelum. Here, I integratively describe these species, combining morphology and DNA barcodes with a molecular analysis including all Zephroniidae species deposited on GenBank—including the only giant pill-millipede species known from Cambodia, Zephronia dawydoffi Attems, 1953. An updated determination key to the species of the genus is presented. Zephronia laotica n. sp. belongs to the monophyletic Zephronia sensu stricto group, which is confirmed by molecular barcoding. In contrast, most species of Sphaerobelum are in a weakly supported clade. Genetically, Sphaerobelum species differ greatly from one another, with most p-distances >15%. The lowest observed p-distance (9.8%) is between S. truncatum Wongthamwanich et al. 2012 from Thailand and S. peterjaegeri n. sp. 

An investigation of chromosome numbers in the genus Brachiaria (Poaceae: Paniceae) in relation to morphology and taxonomy

1987 ◽  
Vol 65 (11) ◽  
pp. 2297-2309 ◽  
Author(s):  
G. P. Basappa ◽  
M. Muniyamma ◽  
C. C. Chinnappa
Keyword(s):  
Chromosome Number ◽  
Chromosome Numbers ◽  
Indian Subcontinent ◽  
Base Number ◽  
Chromosome Races ◽  
Morphological Studies

Determinations of chromosome number and morphological studies of 260 populations, belonging to 32 taxa, of the genus Brachiaria from the Indian subcontinent reveal that all sexually reproducing taxa have no chromosome races. Six agamic taxa, viz., B. brizantha var. brizantha (n = 27), B. brizantha var. ciliata (n = 18), B. decumbens (n = 18), B. hybrida (n = 27), B. mutica (n = 18), and B. setigera var. albistyla (n = 14), have consistently shown uniformity in chromosome numbers, based on x = 7, 8, and 9. Brachiaria setigera var. setigera, a genetically unstable apomict, is the only taxon that tends to have a heteroploid series (n = 16, 17, 18, 21, and 32). The population of B. setigera var. setigera with n = 17 is based on a secondary base number of x = 17. There are 6 diploids, 20 tetraploids, 5 hexaploids, and 3 octoploids in the genus. Aneuploidy and triploidy are characteristically absent in the genus, although their plausible existence in the B. setigera complex cannot be ruled out. In several species certain previously reported chromosome numbers that deviate from the present study are found to be the result of erroneous identifications or the result of taxonomically complex situations such as those found in B. brizantha, the B. distachya complex, and the B. ramosa complex.

Molecular characterization of Anisakis pegreffii larvae in Pacific cod in Japan

2005 ◽  
Vol 79 (4) ◽  
pp. 303-306 ◽  
Author(s):  
N. Abe ◽  
N. Ohya ◽  
R. Yanagiguchi
Keyword(s):  
Light Microscopy ◽  
Sibling Species ◽  
Direct Sequencing ◽  
Its Region ◽  
Single Species ◽  
Sensu Stricto ◽  
The Other ◽  
Pacific Cod ◽  
Pcr Rflp

AbstractIt is now recognized that the morphospecies Anisakis simplex is not a single species but a complex composed of three sibling species, A. simplex sensu stricto, A. pegreffii and A. simplex C. In Japan, A. simplex-like larvae have been isolated from a variety of fish and humans, but the larvae collected have been identified as A. simplex by only light microscopy. Therefore, the epidemiology of the A. simplex complex, composed of three sibling species, is still unclear in Japan. In the present study, 26 A. simplex-like larval isolates were obtained from two Pacific cod landed in Hokkaido, Japan, and examined genetically by PCR–RFLP and direct sequencing of the ITS region of rDNA. Among the 26 isolates, 24 were identified as A. simplex sensu stricto, the other two as A. pegreffii. The present study is the first to confirm the distribution of A. pegreffii in Japan, and to detect A. pegreffii larvae in Pacific cod.

Suitability of forms of preparing seeds of Dalbergia miscolobium Benth for exposure to the tetrazolium test / Adequação das formas de preparação de sementes de Dalbergia miscolobium Benth para exposição ao teste de tetrazolium

2017 ◽  
Vol 1 (1) ◽  
Author(s):  
Juliana Martins de Mesquita Matos ◽  
Rosana De Carvalho Cristo Martins ◽  
Valéria Regina Bellotto ◽  
Lilian Gomes da Silva Rocha ◽  
Eloiza Aparecida Barbosa ◽  
...  
Keyword(s):  
Endangered Species ◽  
Filter Paper ◽  
Federal District ◽  
Complete Removal ◽  
Sensu Stricto ◽  
The Other ◽  
Distrito Federal ◽  
Viable Seeds ◽  
Range Test ◽  
Tetrazolium Test

Dalbergia miscolobium or Jacarandá do Cerrado is a species of legume in the Fabaceae family. It occurs in the sensu stricto Cerrado and in the dystrophic cerradão. It shows potential for landscaping and for recovering damaged areas. It is an endangered species and therefore is protected by the law that prevents cut in areas of the Federal District (Decree No. 14.783/93). The purpose of this study was to determine the best procedure to prepare seeds of Dalbergia miscolobium to assess viability in the tetrazolium test. We carried out the following treatments: i) hydration on filter paper at 25 ° C, ii) hydration on filter paper at 25 ° C followed by a cut in the tegument and iii) hydration on filter paper at 25 ° C followed bya complete removal of the tegument. The results were analyzed using analysis of variance and the Tukey range test. The analyzes showed that the best procedure to prepare seeds of Dalbergia miscolobium is the treatment in which there is a hydration followed by the complete removal of the integument. Where 78% of the seeds showed uniform staining, indicating that the seeds analyzed are of good quality. The other treatments, hydration and hydration followed by cutting, showed respectively 35% and 41% of viable seeds. RESUMO A Dalbergia miscolobium ou Jacarandá do Cerrado é uma espécie de leguminosa da família Fabaceae. Ocorre no sentido stricto Cerrado e no cerradão distrófico. Possui potencial para paisagismo e para recuperar áreas degradadas. É uma espécie ameaçada de extinção e, portanto, está protegida pela lei que previne o corte em áreas do Distrito Federal (Decreto 14.783 / 93). O objetivo deste estudo foi determinar o melhor procedimento de prepararação das sementes de Dalbergia miscolobium para serem submetidas à análise de viabilidade pelo teste de tetrazólio. Foram realizados os seguintes tratamentos: i) hidratação em papel de filtro a 25 ° C, ii) hidratação em papel de filtro a 25 ° C seguida de um corte no tegumento e iii) hidratação em papel de filtro a 25 ° C seguido de remoção completa do tegumento. Os resultados foram analisados utilizando-se a análise de variância e o teste de médias de Tukey. As análises mostraram que o melhor procedimento para preparar sementes de Dalbergia miscolobium é o tratamento em que há uma hidratação seguida pela remoção completa do tegumento, onde 78% das sementes apresentaram coloração uniforme, indicando que as sementes analisadas são de boa qualidade. Os demais tratamentos, hidratação e hidratação seguida de corte, mostraram respectivamente 35% e 41% de sementes viáveis.

scholarly journals Limitation of current probe design for oligo-cross-FISH, exemplified by chromosome evolution studies in duckweeds

Chromosoma ◽  
2021 ◽  
Vol 130 (1) ◽  
pp. 15-25
Author(s):  
Phuong T. N. Hoang ◽  
Jean-Marie Rouillard ◽  
Jiří Macas ◽  
Ivona Kubalová ◽  
Veit Schubert ◽  
...  
Keyword(s):  
Growth Rate ◽  
Chromosome Number ◽  
Chromosome Evolution ◽  
Sequence Similarity ◽  
Flowering Plants ◽  
The Other ◽  
Probe Design ◽  
Congeneric Species ◽  
Specific Design ◽  
Spirodela Polyrhiza

AbstractDuckweeds represent a small, free-floating aquatic family (Lemnaceae) of the monocot order Alismatales with the fastest growth rate among flowering plants. They comprise five genera (Spirodela, Landoltia, Lemna, Wolffiella, and Wolffia) varying in genome size and chromosome number. Spirodela polyrhiza had the first sequenced duckweed genome. Cytogenetic maps are available for both species of the genus Spirodela (S. polyrhiza and S. intermedia). However, elucidation of chromosome homeology and evolutionary chromosome rearrangements by cross-FISH using Spirodela BAC probes to species of other duckweed genera has not been successful so far. We investigated the potential of chromosome-specific oligo-FISH probes to address these topics. We designed oligo-FISH probes specific for one S. intermedia and one S. polyrhiza chromosome (Fig. 1a). Our results show that these oligo-probes cross-hybridize with the homeologous regions of the other congeneric species, but are not suitable to uncover chromosomal homeology across duckweeds genera. This is most likely due to too low sequence similarity between the investigated genera and/or too low probe density on the target genomes. Finally, we suggest genus-specific design of oligo-probes to elucidate chromosome evolution across duckweed genera.

scholarly journals Eurasian and North American phylogeny of Turolian hipparionine horses (Perissodactyla, Mammalia) in China

1992 ◽  
Vol 6 ◽  
pp. 305-305
Author(s):  
Mahito Watabe
Keyword(s):  
North America ◽  
North American ◽  
Northern China ◽  
Sensu Stricto ◽  
The Other ◽  
Dental Morphology ◽  
Facial Morphology ◽  
Open Land ◽  
Specialized Form ◽  
Eastern Half

The late Miocene Chinese hipparions are morphologically diversified showing similarity to both western Old World's and North American forms. Two Chinese taxa that are phylogenetically related to western Old World's forms are Hipparion fossatum (= H. forstende) from Baode (Shanxi) and H. hippidiodus from Qingyang (Gansu) and Baode. The former is related to H. mediterraneum and the latter to H. urmiense - platygenys from the Turolian localities in the western Old World. H. fossatum and H. hippidiodus are associated with the “dorcadoides” (open-land) and “mixed” faunas in northern China. Hipparion fossatum that is characterized by POF located close to the orbit co-occurs with large and morphologically specialized form, H. dermatorhinum in Baode (Loc.30). H. hippidiodus with reduced POF is discovered with smaller H. coelophyes in Loc. 43, 44 (Baode) and Loc. 115 (Gansu).The hipparions associated with the “gaudryi” (forest) fauna are characterized by well defined and small POF located far from the orbit. Those forms are: H. platyodus from Loc. 70; H. ptychodus from Loc. 73; H. tylodus from Hsi-Liang in Yushe - Wuxiang basins; and H. sefvei from Loc. 12 at Xin-an in Henan province. H. coelophyes from Baode (Loc.43 & 44) and Qingyang (Loc. 115) also show similar facial morphology to the these forms, although it has small size and shallow POF. Those forms are similar in facial and dental morphology to Hipparion sensu stricto and some species of Cormohipparion in North America.The assemblages of Chinese hipparions are composed of two groups whose members are phylogenetically similar to the forms from both western part of Eurasia and North America. The “gaudryi” fauna is considered younger than the other two on the basis of faunal analyses. The similarity in hipparionine taxonomy between northern China and North America in the latest Miocene is an evidences for possible faunal interchange(s) occurred during that period, as suggested by taxonomic analyses on carnivores and proboscideans in eastern half of Eurasia and North America.

scholarly journals MORPHOLOGICAL STUDIES IN EXPERIMENTAL CRETINISM

1913 ◽  
Vol 17 (6) ◽  
pp. 636-652 ◽  
Author(s):  
Arthur L. Tatum
Keyword(s):  
Adrenal Glands ◽  
The Body ◽  
The Other ◽  
Degenerative Changes ◽  
Morphological Studies ◽  
Cellular Changes ◽  
Anatomical Basis ◽  
Parenchymatous Organ ◽  
Islands Of Langerhans

In summarizing the findings of this paper it may be said that degenerative changes have been noted in practically every parenchymatous organ. Among these the most striking has been that of serous imbibition by the most active cells of these organs. In regard to the changes in the glands of internal secretion, the findings corroborate the statements of Cushing in regard to hypophysectomy, that removal of one gland of internal secretion results in changes in all the other glands. In this case, degenerative changes predominate in the hypophysis, thymus, ovary, and testis, while hyperplasia is seen in the islands of Langerhans and the medullas of the adrenal glands. Finally, in the rabbit athyroidism is responsible for grave degenerative changes in practically all organs and tissues of the body, and many of the symptoms of cretinism have an anatomical basis in organic cellular changes.

Neotypification of the Linnaean name Iris aphylla (Iridaceae)

Phytotaxa ◽  
2016 ◽  
Vol 273 (2) ◽  
pp. 141 ◽  
Author(s):  
EUGENY V. BOLTENKOV
Keyword(s):  
Chromosome Number ◽  
Western Europe ◽  
Genetic Data ◽  
Single Species ◽  
Point Of View ◽  
European Russia ◽  
European Countries ◽  
Forest Edges ◽  
Variable Species ◽  
Open Forests

Iris aphylla Linnaeus (1753: 38) (Iridaceae) is a highly variable species from the morphological point of view, especially in the height of stem, stem branching, size of leaves, and color of flowers. Moreover, it can be found in different habitats. In the Middle-Russian Upland, this plant is mostly associated with meadow steppes on slopes and, rarely, with edges of shrub thickets; also occurs along forest edges and in open forests, where blooming plants are rare (Kazakova et al. 2015). It is native to Central, Eastern, and some parts of Western Europe. The species is widespread in the Ukraine and mainly in the south of middle European Russia, while in the European countries its populations are sparser. Iris aphylla is of autotetraploid origin (Mitra 1956); plants with the chromosome number 2n = 48 are found more frequently in Europe (Wróblewska et al. 2010). Its numerous synonyms, including four subspecies, indicate the variability of this species. The genetic data confirm the conclusion that the subspecies of I. aphylla should be regarded as a single species (Wróblewska et al. 2010). According to my best knowledge (see also Jarvis 2007) the name I. aphylla is still lacking typification.

Aspidistra revoluta, a new species from limestone areas in Chongqing, China

Phytotaxa ◽  
2016 ◽  
Vol 257 (3) ◽  
pp. 280 ◽  
Author(s):  
Hao Zhou ◽  
Si-rong Yi ◽  
Qi Gao ◽  
Jie Huang ◽  
Yu-jing Wei
Keyword(s):  
New Species ◽  
Chromosome Number ◽  
Average Length ◽  
Chromosome Complement ◽  
Pollen Grains ◽  
The Other ◽  
Morphological Comparison ◽  
Chongqing Municipality ◽  
Karyotype Asymmetry ◽  
A New Species

Aspidistra revoluta (Asparagaceae) is described and illustrated as a new species from limestone areas in southern Chongqing Municipality, China. The new species can be distinguished from the other Aspidistra species by its unique umbrella-like pistil with large revolute stigma lobes that bent downwards and touch the base of the perigone. A detailed morphological comparison among A. revoluta, A. nanchuanensis and A. carnosa is provided. The pollen grains of A. revoluta are subspherical and inaperturate, with verrucous exine. The chromosome number is 2n = 38, and the karyotype is formulated as 2n = 22m + 6sm + 10st. The average length of chromosome complement is 4.50 μm, and the karyotype asymmetry indexes A1 and A2 are respectively 0.37±0.03 and 0.49±0.01.

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