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1.
Amphidinium operculatum Claparède et Lachmann, the type species of the dinoflagellate genus Amphidinium, has long had an uncertain identity. It has been considered to be either difficult to distinguish from other similar species or a morphologically variable species itself. This has led to the hypothesis that A. operculatum represents a “species complex.” Recently, the problem of distinguishing A. operculatum from similar species has become particularly acute, because several morphologically similar species have been found to produce bioactive compounds of potential interest to the pharmaceutical industry. In this study, we cultured and examined existing cultures of several species of Amphidinium, most of which have been previously identified as A. operculatum or as species considered by some to be synonyms or varieties of A. operculatum. Thirty strains were examined using comparative LM, SEM, and partial large subunit (LSU) rDNA sequence data. Through morphological and molecular phylogenetic analyses, six distinct species were identified, including Amphidinium trulla sp. nov. and Amphidinium gibbosum comb. nov. Amphidinium operculatum was redescribed based on four cultures. Genetic variability within the examined Amphidinium species varied greatly. There was little difference among strains in partial LSU rDNA for most species, but strains of A. carterae and A. massartii Biencheler differed by as much as 4%. In both A. carterae and A. massartii, three distinct genotypes based on partial LSU rDNA were found, but no morphological differences among strains could be observed using LM or SEM. In the case of A. carterae, no biogeographically related molecular differences were found.  相似文献   

2.
《Journal of bryology》2013,35(3):153-155
Abstract

The taxonomy of Anomobryum julaceum and allied species with axillary bulbils in Europe and Asia is reviewed. A. concinnatum is regarded as a distinct species, occurring in W. and C. Europe, SW., N. and C. Asia and N. America. A. bavaricum has often been confused with A. concinnatum, but differs in its more numerous, small, reddish bulbils and in leaf shape; it is known only from the European Alps. The Asian A. nitidum also has numerous small reddish bulbils but it differs from A. bavaricum in leaf shape and bulbil form. A lectotype is designated for A. nitidum, of which A. gemmigerum and other nominal taxa are regarded as synonyms. Information is presented on geographical ranges and habitats of the four valid species.  相似文献   

3.
Zusammenfassung A. sagittata (Bertol.) DC. von zehn Herkünften aus Europa ist mit 2 n=16 diploid.A. hirsuta (L.)Scop. s. str. einschließlich der sicherlich hierhergehörigen var.glaberrima Wahlenb. von 30 europäischen Herkünften ist mit 2 n=32 tetraploid; diploide Pflanzen konnten beiA. hirsuta s. str. nicht gefunden werden.
Summary A. sagittata (Bertol.) DC. from 10 different places in Europe has 2 n=16 chromosomes and is diploid.A. hirsuta (L.)Scop. s. str., its var.glaberrima Wahlenb. being included, has been investigated from 30 provenances in Europe, it has the tetraploid chromosome number 2 n=32, diploid plants could not be found in this species.A. hirsuta var.glaberrima (2 n=32) is surely belonging toA. hirsuta s. str. and not toA. allionii (2 n=16).
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4.
Freshwater dinoflagellates have not previously been reported from Belize, although there has been extensive work with marine dinoflagellates and some work with other freshwater groups. Freshwater dinoflagellates are more frequently observed in standing water and none have been observed in the several streams and rivers sampled since 1990. The goal in 1998 was to examine water samples from small ponds within hours of collection to improve the chance of observing swimming dinoflagellates. A plankton net was used and whole water samples also were collected. A small brown water pond on a peninsula and 30m from the Caribbean yielded a bloom of Thompsodinium intermedium. Dinoflagellates, including Peridinium centenniale, Katodinium sp., and Peridinium sp. in the Umbonatum Group, were observed within “Crocodile pond” and “Lily pond” on the mainland.  相似文献   

5.
A new species ofPichia has been described.Pichia besseyi was isolated from a marsh near the town of Bonaventure, Gaspé Peninsula, Quebec, Canada. The hemispheroidal shape of the ascospores of this species is particularly noteworthy.  相似文献   

6.
A new species of thermophilicStreptomyces has been isolated from a soil sample collected in Bombay. Its morphological characteristics and physiological behaviour have been studied in detail. It has thus been found to belong to Series XVI-Thermophilus of Waksman's scheme of classification (1961). Its similarity to and differences from a few known species are described. It has been designated asStreptomyces thermonitrificans.  相似文献   

7.
A new species, Pygidiopsis ardeae (Heterophyidae, Pygidiopsinae), is described, using both light and stereoscan electron microscopy, from the grey heron Ardea cinerea L. (Ardeidae) from Denmark. The species has previously (as P. genata) been recorded in dogs fed on plaice and flounders from Danish waters. It developed experimentally in domestic chickens and pigeons. No species of Pygidiopsis Looss, 1907 has previously been described from birds in northern Europe. P. ardeae is very similar to the type-species, P. genata Looss, 1907, from Egypt, but the two species have different life-cycles. P. ardeae differs from P. piclaumoreli Dollfus & Capron, 1958 from Senegal in its size and the disposition of vitelline follicles. P. plana (Linton, 1928) Price, 1933, from a green heron from the eastern USA, is larger than P. ardeae and has a wide, sac-like prepharynx.  相似文献   

8.
Ram Dayal  Tharur Ji 《Hydrobiologia》1968,32(1-2):237-244
Summary In continuation with the studies in aquatic fungi of Varanasi, four more fungi viz., Achlya apiculata, A. oblongata var. oblongata, Blastocladiella simplex and Pythiogeton ramosum have been isolated and described as occurring new to the Indian aquatic flora; while P. sterilis has been assigned to synonymy under P. ramosum Hamid's isolate A. oblongata var. oblongata has been excluded from the valid identification.  相似文献   

9.
Three distinct types of embryo have been found in 18 species of the genus Oryza. Type 1 is characterized by lateral fusion of the epiblast and the scutellum and also by the development of auricles. Type 2 has no auricle, and the epiblast is not laterally fused with the scutellum. Type 3 has a cleft between the lower part of the scutellum and the coleorhiza, a long epiblast which is free from the scutellum, and lacks auricles. Type 1 has been found in 13 species of section Sativae, Type 2 in 4 species of sections Granulatae and Coarctatae, and Type 3 in O. coarctata only. The results indicate that species of section Sativae are more or less closely related, while section Coarctatae is a heterogeneous group. A new section, Ridleyianae, has been described for Oryza ridleyi and some other species. Oryza coarctata has unique features in embryo structure, morphology and leaf anatomy, and this species has been moved from the genus Oryza to a separate genus, Sclerophyllum, which is here revived.  相似文献   

10.
A preliminary survey has been made of the desmid genus Micrasterias in Tasmania, as the first part of an intended series of detailed investigations of Tasmanian freshwater algae. For comparative purposes, samples from the south-eastern states of mainland Australia are included. Micrasterias hardyi West, apparently an Australian endemic, is discussed in detail and M. tropica var. indivisa (Nordst.) Eichl. et Racib., formerly known only from New Zealand, is figured from Tasmania. Some other Micrasterias forms are readily accommodated within the existing nomenclature. Others, however, have been uncertainly allied with existing taxa in keeping with a policy of not adding to the burden of nomenclature until a biological concept of species has been developed for the desmids. The taxonomy of Australian representatives of the genus Micrasterias is discussed against this background.  相似文献   

11.
Summary A new haploid, homothallic yeast isolated from the larval feed ofXylocopa caffra is described. A study of its properties shows that the evolution of its sexual and biochemical characteristics has not taken place at the same rate as in the genusHansenula and the proposed genusDekkeromyces. This led the author to the conclusion that in the yeast domain phylogenetic lines may exist in which a unilateral evolution of biochemical characteristics has taken place. At least thre groups of yeasts exist where such discrepancies exist between the evolution of their sexual and biochemical characteristics. The inclusion of the new species in these groups is discussed. The new species has provisionally been classified in the genusPichia (in sensu Phaff). A Latin diagnosis of the species is given.  相似文献   

12.
The new species Armeria saviana, endemic to an isolated mountain chain of the Tyrrhenian Antiappennine system in south Tuscany, central Italy, is described and illustrated. The plant is diploid with 2n=18. It can be distinguished from the related species A. denticulata (Bertol.) DC and A. canescens (Host) Ebel, mainly by leaf characters, capitula, bracts and flowers. The systematic position of the controversial taxon A. majellensis Boiss. subsp. ausonia F. Bianchini, to which the new species has formerly been assigned by some authors, is discussed. A lectotype for A. denticulata is designated.  相似文献   

13.
《Journal of bryology》2013,35(3):449-450
Abstract

A single, small moss leaf has been found among very small amounts of contents extracted from the Tyrolean Iceman's colon. It belongs to the species Neckera complanata Hedw., a woodland moss of low to moderate altitudes. The leaf was accidently ingested and not consumed as food.  相似文献   

14.
Summary A diploid Allium cepa plant was recovered from the backcross of an interspecific triploid (2 x A. cepa + 1 x A. fistulosum) to an A. cepa diploid which exhibited both A. cepa and A. fistulosum Adh-1 alleles. Cytogenetic analyses revealed a recombinant sub-telocentric chromosome. The ADH-1 locus is believed to be on the long arm of the sub-telocentric A. fistulosum chromosome 5. Meiosis of the triploid progenitor gives strong evidence that recombination occurred. A. fistulosum chromosome 8 has been substituted for A. cepa chromosome 1.Contribution of the College of Agricultural Sciences, Texas Tech University, Journal No. T-4-275  相似文献   

15.
A new species ofPichia has been described.Pichia angophorae sp.n. was the only yeast present in an exudate ofAngophora costata collected near North Ryde, N. S. W., Australia. The new species exists in both the homo- and heterothallic state. Heterothallic mating types have been isolated as segregants from originally homothallic cultures.  相似文献   

16.
A chlorarachniophycean alga, Lotharella amoebiformis, which has been classified in the genus Lotharella is placed into a new genus Amorphochlora gen. nov., based on its phylogenetic position, which has been clarified by the recently accumulated molecular phylogenetic information, and the morphological difference between the vegetative cells of the Lotharella species. Following this taxonomic treatment, a new combination Amorphochlora amoebiformis comb. nov., is proposed.  相似文献   

17.
Riassunto Lo studio comprende una revisione critico-sperimentale della specie Actinomyces albus, della quale vengono considerati come sinonimi circa 30 nomi speeifici, fra i quale A. chromogenus, A. odorifer, A. thermophylus p.p.; della specie é data una diagnosi ed una particolareggiata descrizione.Sono inoltre studiate le specie A. viridis, (= A. viridochromogenus) e A. innominatus, n. nomen. Quest'ultima é preceduta da una breve discussione sulla specie A. homini.
Summary Twenty-six strains of Actinomyces albus are studied redescribed from morphological, cultural and biochemical standpoints. Many biological activities of A. chromogenus, A. odorifer and A. thermophilus are in common with other species of the same genus, so that they may be considered for sub-specific, (not specific) differentiation. A discussion on A. farcinicus, A. albidoflavus and A. aureus has been originated from mislabeling as A. albus; the group including the two last named species (flavus group) must be revised. A few strains classified A. farcinicus are in no doubt true A. albus, but this real specific entity remains to be revised from Nocard's strain. A. viridis, for the first time described by Lombardo-Pellegrino, has been redescribed three times as a new species under the same binomial, and the fourth as A. viridochromogenes. A. hominis Bostroem is an uncorrect determination for the species originally described by Waksmann and Curtiss, and it is renamed A. innominatus, the binomial A. (Streptothrix) hominis Auct. being a nomen ambiguum. In conclusion, 30 bionmial are appended in sinonimy to A. albus, including Cladothrix dichotoma Macé (1888) non Cohn, G. invulnerabilis Acosta et G. Rossi, C. odorifera Rullm. Actinomyces chromogenus Gasp., A. thermophilus Auct., p.p., A. (Streptothrix) Sanninii (Cif.) Westerd., A. Almquisti Duché, A. Gougeroti Duché, and so on.
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18.
With the object of studying the genomic relationships of Brassica tournefortii Gouan with the other elementary species of Brassica viz. B. campestris (2n=20, A genome), B. oleracea (2n=18, C genome) and B. nigra (2n=16, B genome), it has been hybridized with them. The percentage of F1 hybrids formed, their morphology and meiotic behaviour have been described. Based upon crossability relationships and meiotic pairing in the F1 hybrids, it is inferred that the D genome of B. tournefortii is more closely related to the A genome than to the B and C genomes. It may have been derived from the A genome which likewise shows a strong genetic isolation from B and C. The species has developed a strong genetic barrier in the course of its evolution and shows little crossability, high hybrid sterility and no gene flow with any of the other elementary species. The fact that it has not formed any natural amphidiploids with the elementary species which otherwise are formed in all combinations, is more evidence that it originated more recently than the A genome. It is presumed that B. tournefortii, being more distantly related to B. nigra than to other elementary species, may form stable artificial aphid resistant amphidiploids with the former.  相似文献   

19.
A high altitude shrub birch from Bhutan, south‐east Tibet, north‐west Yunnan and western Sichuan, which has been referred to the tetraploid Betula utilis, is shown to be a distinct diploid species, described here as Betula ashburneri McAllister & Rushforth.  相似文献   

20.
A new species of the genus Pichia has been described. The species was isolated from a 70 percent solution of d-sorbitol and is distinctly osmotophilic.  相似文献   

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