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1.
Paolo Caputo Salvatore Cozzolino Luciano Gaudio Aldo Moretti Dennis W. Stevenson 《American journal of botany》1996,83(11):1513-1520
Chromosome numbers and karyotypes of four species of Zamia L. (Zamiaceae) are described. Plants of Z. manicata from Colombia are 2n = 18 with eight metacentric (M), four submetacentric (S), two acrocentric (A), and four telocentric (T) chromosomes. Plants of Z. ipetiensis from Panama are 2n = 23 with 3M + 4S + 2A + 14T. Plants of Z. cunaria from Panama have two different chromosome numbers, 2n = 23 with 3M + 4S + 2A + 14T and 2n = 24 with 2M + 4S + 2A + 16T. Plants of Z. acuminata from Costa Rica and Panama are 2n = 24 with 2M + 4S + 2A + 16T. On the basis of the occurrence of a one-to-two-ratio in the variation of M- and T-chromosome numbers in the karyotypes, centric fission or fusion are considered for their potential involvement in the chromosome variation of these plants. Data deriving from morphology and karyology, interpreted in a cladistic framework, suggest that centric fission rather than centric fusion is involved in the karyotype diversification of the four species and their closest Mesoamerican allies. 相似文献
2.
P. A. Clancey 《Ibis》1967,109(3):318-327
The four major groupings into which the Zosterops forms of southern African can be arranged have for long been treated by conservative systematists as constituting four discrete species (Z. capensis, Z. pallidus, Z. virens and Z. senegalensis). In a major study, published in 1957, Moreau arrived at the tentative conclusion that in zoo-geographical South Africa Z. cupensis and Z. wirens are clearly conspecific, Z. pallidus is a doubtful monotypic species, and Z. senegalais is a polytypic species of wide continental range, specifically segregated from the foregoing on the basis of a wingltail ratio character, and of juxtaposition without evidence of interbreeding. A new study of the complex problem of Zosterops relationships in South Africa based on a critical study of over 900 specimens examined in the Durban Museum, suggests that only two species (Z. pallidus and Z. senegahsis), very closely related and part of the same superspecies, are actually involved. 相似文献
3.
Dr. Ingvar Leiv Leknes 《Cell and tissue research》1981,218(1):23-28
Summary Widened myocardial Z bands and endocardial cells are described in two teleostean species Cichlasoma meeki and Corydoras aeneus. Widened Z bands containing mainly amorphous and electron-dense material were seen in a number of myocardial cells. Further, similar material may occur in large amounts beneath the sarcolemma and at intercellular junctions. Occasionally, we observed continuity between the latter material and that in expanded Z bands.In C. meeki the ventricular endocardial layer consists of two structurally different cell types, whereas in C. aeneus only one cell type was seen. The functional aspects of widened Z bands are discussed. 相似文献
4.
The composition of oil gland exudates from two oribatid mites, Trhypochthoniellus sp. and Trhypochthonius
japonicus, was studied with reference to the related species Trhypochthoniellus
crassus. Trhypochthoniellus sp. contained a mixture of seven compounds; (Z,Z)-6,9-heptadecadiene, geranial, 3-hydroxybenzene-1,2-dicarbaldehyde (γ-acaridial),
neryl formate, neral, (Z)-8-heptadecene and geranyl formate in decreasing order of abundance. The profile of the components
from T. japonicus consisted of two types depending on the locality of sampling with unknown reason; one possessing a mixture of eight compounds
[(Z,E)-farnesal, γ-acaridial, (Z,Z)-6,9-heptadecadiene, (E,E)-farnesal, (Z)-8-heptadecene and geranial in decreasing order]
together with two unknown compounds, and the other composed of the same set of compounds together with 2-hydroxy-6-methylbenzaldehyde
as the most abundant component. Relative abundance among common components was consistent between the two types of T. japonicus. Profiles of components differed among three species including T. crasus. The phylogenetic relationship between Oribatida and Astigmata was discussed based on secretory compounds commonly distributed
between these two suborders.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
5.
The structure of the predatory freshwater flagellate Colpodella pseudoedax was studied. The cell was found to contain two heterodynamic flagella, three-membrane pellicle, micropores, subpellicular
microtubules, microtubular open-side conoid, roptries, micronemes, extrusive organelles (trichocysts), and mitochondria with
vesicular and tubular cristae. Upon discharge, trichocysts form cross-striated bands. A thin-walled cylinder lies in the transitional
zone of the flagella. Cells reproduce by means of longitudinal binary fission. This species differs from similar C. edax by their smaller cell size and lack of reproduction cyst. Similarities between C. pseudoedax and other colpodelids, as well as between colpodellids and perkinseids and sporozoans, are discussed. 相似文献
6.
A. P. Mylnikov 《Biology Bulletin》2009,36(6):582-590
The structure of cells of the predatory flagellates Colpodella pseudoedax and C. unguis was studied. The cell was found to contain two heterodynamic flagella, three-membrane pellicle, micropores, subpellicular
microtubules, microtubular open conoid, roptries, micronemes, extrusive organelles (trichocysts), and mitochondria with tubular
cristae. Upon discharging, trichocysts form cross-striated bands. The thin-walled cylinder lies in the transitional zone of
the flagella. Cells reproduce by means of longitudinal binary fission. The similarities between given species and other colpodelids
and such between perkinsea, sporozoans, and dinoflagellates are discussed. 相似文献
7.
L.A. Mound 《New Zealand journal of zoology.》2013,40(4):615-222
Abstract Three new species of genus Thrips are described—austellus, coprosmae, and phormiicola—which are closely related to the common New Zealand species T. obscuratus (Crawford). The systematic and zoogeographic significance of this endemic species-group is discussed. Physemothrips hadrus n.sp. is described from the South Island; the only other member of this genus is from Macquarie Island. Anaphothrips zelandicus n.sp. is described from the South Island and the Chatham and Antipodes islands, A. woodi Pitkin is recorded from New Zealand, and the relationships of these two species to the Australian fauna are discussed. 相似文献
8.
Crataegus coriifolia Sharifnia & Zarrinkolah is described as a new species from Iran. Its taxonomic relationships, ecology and distribution are discussed. An identification key to C. coriifolia and other two‐styled species of Crataegus occurring in Iran is provided. 相似文献
9.
An integrative approach for species delimitation in the spider genus Grammostola (Theraphosidae,Mygalomorphae)
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The mygalomorph genus Grammostola (family Theraphosidae) is endemic to South America. The species Grammostola anthracina is one of the largest spiders in Uruguay and reputed to be the longest lived tarantula in the world. This nominal species has two distinct colour morphs comprising black and reddish‐brown forms with controversial taxonomic status. Here, we present a phylogenetic study based on molecular characters (cytochrome c oxidase subunit I) of haplotypes of G. anthracina and closely related species. Our analysis together with new morphological data and biogeographical information indicates that the two morphs of G. anthracina constitute different species that are not sister to each other. Consequently, a new species, Grammostola quirogai is described, diagnosed and illustrated to encompass the black morph. Phylogenetic relationships and new taxonomic characters for Grammostola species included in this study are discussed. 相似文献
10.
Patricia G. Gensel 《American journal of botany》1982,69(5):651-669
A new species of Zosterophyllum, Z. divaricatum Gensel, is described from the late Early Devonian (Emsian) of northern New Brunswick, Canada. It is a Platyzosterophyllum type, consisting of slender sometimes bifurcating axes with laterally borne sporangia oriented to one side of the axis. The species is distinctive in that axes bifurcate within fertile regions and in sporangium shape and attachment. Aspects of the morphology of axis and sporangium cuticle, tracheids, and spores are presented and considered in relation to comparable features in other Zosterophyllum species. Associated vegetative axes exhibiting H- and K-branching patterns and also cuticular features similar to the fertile specimens are described and it is suggested that they may represent parts of the same plant. Zosterophyllum divaricatum is most similar to Z. llanoveranum, Z. fertile, and Z. spectabile, and also resembles Rebuchia ovata to some extent. Z. divaricatum offers considerable information on variation within one species concerning sporangium shape, attachment, and distribution and expands the known diversity of Platyzosterophyllum types. 相似文献
11.
Raşit Urhan 《Biologia》2010,65(1):92-98
In this study, two new species of zerconid mites, Zercon domanicensis sp. n. and Z. yusufi sp. n., are described and illustrated on the basis of materials collected from Turkey. The similarities and differences between
the species were discussed. 相似文献
12.
William A. S. Sarjeant 《Grana》2013,52(2-3):49-56
The history of study of these dinoflagellates is reviewed and emended diagnoses are proposed for the genera Ctenidodinium and Dichadogonyaulax. A new species, Dichadogonyaulax sellwoodii, is described and illustrated from the Bathonian of the Isle of Skye, Scotland. The new combination Dichadogonyaulax norrisii (Pocock, 1972) is proposed and it is considered that forms described by Gocht (1970) as Ctenidodinium pachydermum (Deflandre, 1938) may in fact be'attributable to Pocock's species. The species Ctenidodinium continuum Gocht, 1970, is briefly discussed and other Jurassic species attributable to these two genera are listed. 相似文献
13.
The genus Skidmorella Johnson, previously known only from the South Pacific islands, is discovered in Japan. The type species, Skidmorella magnifica Johnson, is confirmed from Japan as the first record of the species other than the type locality. In addition, two new species, Skidmorella amamiana sp. nov. and Skidmorella quadrisulucia sp. nov., are described from the Ryukyus, Japan. Phylogenetic relationships of the genus Skidmorella and its allies are discussed on the basis of their morphological characters. 相似文献
14.
15.
Adam S. Bursa 《Grana》2013,52(3):54-66
The formative ability of ectoplasm in situ and in isolation from the living cell is shown to be an autodynamic morphogenetic factor creating sui generis membrane structure in species. Heteromorphic division and formation of specific aberrants, which differ from the parent cell by characters which have been used to separate genera, may be caused by molecular changes in ectoplasm as a primary factor. The subpellicular vacuom reticulum in Gyrodinium and other genera originates possibly from the upset metabolism of protoplasm. It is purely phenotypic. Oxygen deficiency induces in Prorocentrum endogenous cysts and dwarf-cell formation, a plasmolysis-like effect. The morphological norm in dinoflagellates is maintained also by the angle of nuclear fission and ensuing cytoplasm disposition. It is constant in sea and culture in some species, almost constant in sea but multivariable in culture in other species. The static form in some species is related to a single method of division (Exuviaella marina). Polymorphy of Exuviaella, Prorocentrum and other genera is induced by the presence of many types of divisions, which also favours an abundance of aberrants. “Osmomorphoses” originate in critical salinity-temperature conditions owing to flexibility of the pellicle in Gymnodinioideae; it is prevented by the membrane rigidity in the thecate forms. Flexibility of membrane in juvenile cells favours exogenous division. Rigid membranes of adult cells inhibit exogenous, favour endogenous fission. “Cyclomorphoses”, “phagomorphoses” (feeding habit) and different types of aberrants are useful to complete classification in modern and fossil dinoflagellates since morphogenesis rules work regardless of time and space. 相似文献
16.
A. C. Eyles 《New Zealand journal of zoology.》2013,40(3):181-215
Abstract Six genera and 11 species of Orthotylinae are now known from New Zealand. Zanchius Distant is newly recorded. One new genus, Tridiplous, and seven new species of endemic New Zealand Orthotylini are described and illustrated. Four new species are described in Tridiplous: T. burrus, T. parvapiatus, T. penmani, and T. virens, and three new species are described in Zanchius: Z. ater, Z. rubicrux, and Z. totus. Keys are provided to identify New Zealand taxa of the tribes of Orthotylinae, genera and species of Halticini, genera of Orthotylini, and species of Tridiplous and Zanchius. The bugs are illustrated with colour habitus photos, and drawings including male and female genitalia. Economic importance is discussed. 相似文献
17.
Paraphysomonas faveolata sp. nov. (Chrysophyceae), a fourth marine species with meshwork body-scales
Paraphysomonas faveolata sp. nov., the eighth described species of this genus of colourless chrysophycean flagellates, has heterokont flagellation, parabasal nucleus and silicified body-scales. It is the fourth known species with meshwork scales, these being of two types: flat “cobweb” scales and scales with a planar “honeycombed” extension arising from a “cobweb” base. The organism is compared with the other species of the genus and the case considered for placing forms with meshwork scales in a new genus, separate from forms with spined scales. This step is not taken and the taxonomic status of the genus is discussed in relation to the Ochromonadaceae and other genera of the Synuraceae. 相似文献
18.
A new partial cranium (UW 88-886) of the Plio-Pleistocene baboon Papio angusticeps from Malapa is identified, described and discussed. UW 88-886 represents the only non-hominin primate yet recovered from Malapa and is important both in the context of baboon evolution as well as South African hominin site biochronology. The new specimen may represent the first appearance of modern baboon anatomy and coincides almost perfectly with molecular divergence date estimates for the origin of the modern P. hamadryas radiation. The fact that the Malapa specimen is dated between ~2.026–2.36 million years ago (Ma) also has implications for the biochronology of other South African Plio-Pleistocene sites where P. angusticeps is found. 相似文献
19.
During 1988 and 1989, 409 specimens of southern African Anura, comprising 50 species in 9 families, were checked for opalinids in the cloaca. Protozelleriella devilliersi n. g., n. sp. was found in three of four Capensibufo rosei (Bufonidae); Zelleriella africana Sandon, 1938 in two of three Bufo angusticeps and one of 20 B. garmani (Bufonidae) plus three of 12 Phrynobatrachus natalensis, 12 of 19 Tomopterna cryptotis, seven of 14 T. delalandii, three of seven T. krugerensis and one of six T. natalensis (all Ranidae); Z. gambieri n. sp. in one of six T. natalensis; Z. garlandi n. sp. in two of six Kassina maculata (Hyperoliidae); Z. sandoni n. sp. in two of 20 B. garmani, two of six K. maculata, one of seven K. senegalensis and one of four Leptopelis mossambicus (Hyperoliidae) plus one of five Phrynomerus bifasciatus (Microhylidae) and two of 19 T. cryptotis. It is suggested that the Ranidae (in particular the genus Tomopterna) and the Hyperoliidae are among the major carriers of Zelleriella in the Afrotropical Region. 相似文献
20.
Jacquemontia chrysanthera, a new species from northeastern Brazil, is described and illustrated, and its relationships with Jacquemontia martii and other species in section Cymosae are discussed. 相似文献