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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.
Sphagnum magellanicum has been viewed as being a predominantly circumpolar species in the northern hemisphere, but it occurs in the southern hemisphere and was originally described from the southern parts of Chile. It is an ecologically important species in mire ecosystems and has been extensively used as a model to study processes of growth, carbon sequestration and peat decomposition. Molecular and experimental studies have, however, revealed genetic structure within S. magellanicum, and morphological differences associated with these genetic groups. Here we describe Sphagnum divinum in Sphagnum subgenus Sphagnum (Sphagnaceae, Bryophyta) as a new species, based on molecular and morphological evidence. Sphagnum medium is reinstated as a distinct species and is epitypified. Consequently, a new species concept of S. magellanicum is presented including an epitypification. Important morphological characters to separate these three species in the field and under the microscope are presented. Ecology and distribution differ among the species; S. divinium has a wide habitat range including mire margin, forested peatlands and moist heaths, and a circumpolar distribution around the northern hemisphere. Sphagnum medium seems to be more restricted to ombrotrophic mire expanse habitats and shows an amphi-Atlantic distribution in the northern hemisphere. Sphagnum magellanicum has a very broad ecological niche in peatlands and is found in most mire habitats in Tierra del Fuego on the southern tip of South America.  相似文献   

3.
4.
A new species of Blastobotrys Klopotek (1, 2, 4, 5) has been recovered from white pepper. It appears to be sufficiently distinct from B. nivea v. Klopotek. (5), B. proliferas Marvanová, and B. aristata Marvanová (2), to be described as a new species under the name of Blastobotrys navarrensis. Both morphological as well as physiological characteristics were taken in account to differentiate the new species from Blastobotrys species known up to date.  相似文献   

5.
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   

6.
Species of the genus Culicoides (Diptera: Ceratopogonidae) are well known for their importance in the field of medical and veterinary entomology. Culicoides spp. transmit a wide variety of pathogens, primarily viruses that affect animals and humans. In Europe, the most economically important disease transmitted by Culicoides is bluetongue (BT). Culicoides spp. have been recently involved as primary vectors for Schmallenberg disease. The taxonomy within the subgenus Culicoides has been historically difficult and reorganizations have been proposed regularly. The subgenus Culicoides includes species that are considered to be potential vectors for BT. High morphological intraspecific variability has been attributed to these species. This highlights the apparent presence of previously undetected cryptic species diversity in the subgenus. In the present study, a detailed morphological and molecular study of specimens belonging to Culicoides pulicaris s.l. and specimens resembling a cross between C. pulicaris and Culicoides punctatus revealed the presence of two new species: Culicoides cryptipulicaris and Culicoides quasipulicaris. Females of C. quasipulicaris and males of both species were morphologically distinguished from C. pulicaris (Linnaeus, 1758), whereas females of C. cryptipulicaris were identified using molecular techniques exclusively.  相似文献   

7.
In the course of studies to typify what has been regarded as the most widespread and common of the endemic Philippines species of Nepenthes, N. alata Blanco, we were able to review the morphological variation in what we previously regarded as a polymorphic species. This led us to redelimit that species in a narrower sense, to resurrect N. graciliflora Elmer, and to recognise N. negros sp. nov., here assessed as ‘Critically Endangered’ (CR) using the IUCN standard. The Nepenthes alata group is characterised and a key to its species is provided.  相似文献   

8.
The ascigerous teleomorph of Candida lipolytica (Harrison) Diddens et Lodder, previously classified as Endomycopsis lipolytica Wickerham et al. and as Saccharomycopsis lipolytica (Wickerham et al.) Yarrow, has been assigned to the new genus Yarrowia. Yarrowia lipolytica (Wickerham et al.) comb. nov. is the type species for the genus.The remaining species of Saccharomycopsis are revised.  相似文献   

9.
Two new species of Philodendron– Araceae (Philodendron bernardopazii E. G. Gonç. and Philodendron ricardoi E. G. Gonç.), so far known to be endemic to the Espirito Santo State, Brazil, are here described and illustrated for the first time. Philodendron bernardopazii has been traded as an ornamental plant for more than 30 years, as one of several species popularly called Philodendron“Santa Leopoldina”, because of the Brazilian county where it has been collected. This new species is so far known from two cultivated stocks, both supposedly collected at the same location (around the village of Santa Leopoldina) and if it still exists in nature, it is probably threatened. Philodendron ricardoi has only been observed on rocks around the village of Estrela do Norte where huge populations can be seen growing in rocky outcrops in open areas.  相似文献   

10.
Salvia involucrata Cav., the Rose‐leaf sage, is a species endemic to east Mexico which has been in cultivation since at least the late 18th century. It is little‐known as a native species but is widely cultivated and various cultivars and cultivated hybrids are also known. Salvia puberula Fern. is treated as belonging to S. involucrata but has been subject to different interpretations over the years.  相似文献   

11.
The red alga Pachymeniopsis lanceolata, formerly known as Grateloupia lanceolata, is a component of the native algal flora of northeast Asia and has been introduced to European and North American waters. It has been confused with a cryptic species collected from Korea and Italy. Our analyses of rbcL, cox3 and ITS from P. lanceolata and this cryptic species has revealed two distinct entities, forming a clade, which were clearly separated from its congeners and positioned with other Asian species. Here, we describe the cryptic species as P. gargiuli sp. nov., a species that differs from others by molecular sequence and subtle anatomical characters. We hypothesize that P. gargiuli may have been recently dispersed by anthropogenic vectors, possibly at or near the same time as was P. lanceolata. Our cox3 data set revealed that one haplotype of P. gargiuli, shared between Korea and Italy, and two haplotypes of P. lanceolata, commonly occurring in Korea and USA, are invasive haplotypes. This is the first report of the utility of the mitochondrial coding cox3 sequences in red algae.  相似文献   

12.
Abstract

Embryological researches in the «Thalictrum» genus. II. Embryology and caryology of «Thalictrum lucidum» L. and «Thalictrum minus» L. ssp. «minus». — In their development the female gametophytes of Thalictrum lucidum L. and Thalictrum minus L. ssp. minus follow the Normal type. In the female gametophytes of these species several types of antipodal cells occurs such as: their considerable enlargement, formation of many antipodals polyploid or polinucleated antipodal cells. In these various types, however, a rapid regression of the antipodals occurs. In T. lucidum some tendency to a disposition of the tetrapolarized type has been verified. The chromosome number has been confirmed to ben 2n=28 in besides, in the pollen development, many cases of regression of the microspores has been verified. The chromosome number has been confirmed to ben 2n=28 in Thalictrum lucidum L., and has been found to ben 2n=14 in Thalictrum minus L. ssp. minus, a new number in this species, which was earlier reported to have 2n=42.  相似文献   

13.
A new species of Mallomonas (Synurophyceae), Mallomonas jejuensis sp. nov., has been found in Jeju Island, South Korea. This species is placed in the series Mangoferae (section Torquatae) because it has a collar of elongated domed scales, domeless body scales, rear scales with spines and all scales ornamented with papillae. The morphological characteristics of the scales and bristle of the new species are described by EM and compared with those reported for the other species of the series Mangoferae.  相似文献   

14.
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   

15.
The diversity of the bladed species of the red algal order Bangiales from the Iberian Mediterranean shores has been reassessed after a detailed study of this region. Prior to this study, 11 bladed species of Bangiales had been reported from Mediterranean waters: Porphyra atropurpurea, P. cordata, P. coriacea, P. dioica, P. linearis, P. purpurea, P. umbilicalis, Pyropia leucosticta, Pyropia koreana (as P. olivii), Py. elongata (as P. rosengurttii) and Py. suborbiculata. A combined analysis of the nuclear nSSU and the plastid rbcL genes together with detailed morphological studies has confirmed the presence of species within the genera Porphyra and Pyropia and also revealed a third, undescribed genus, Themis gen. nov. Porphyra linearis, Pyropia elongata and the introduced Pyropia koreana had been previously listed for the Mediterranean and were recorded in this study. An additional four species, including the introduced Pyropia suborbiculata and three new species: Pyropia parva sp. nov., Themis ballesterosii sp. nov., and Themis iberica sp. nov. were also observed. Hence, most of the Porphyra species traditionally reported along these shores were not reported in this survey. This new floristic Bangiales composition confirms the importance of the Mediterranean basin as a hotspot for biodiversity, possible endemics of ancient origin and high proportion of introductions. Our data also continue to confirm the extent of Bangiales diversity at regional and worldwide levels.  相似文献   

16.
The genus Kermadecia (Proteaceae), originally described as endemic to New Caledonia, has been expanded in recent decades to include three species from the New Hebrides and Fiji. Specialists on the Proteaceae have suggested that the three Melanesian species were generically misplaced, and careful reexamination supports this viewpoint. It is now apparent that a distinct group within the subfamily Grevilleoideae is composed of the genera Euplassa (endemic to South America), Sleumerodendron (a monotypic New Caledonian genus), Gevuina (based on a single South American species but recently expanded to include two other species from Queensland and New Guinea), and the three questionable Melanesian species. A review of this cluster of taxa indicates that Gevuina should again be interpreted as restricted to South America and that the generic name Bleasdalea F. v. Muell. ex Domin should be adopted for a group of five species extending from Queensland and New Guinea to the New Hebrides and Fiji. The relationships of the four genera are discussed and within Bleasdalea four new combinations are proposed: B. bleasdalei (F. v. Muell.), B. ferruginea (A. C. Sm.), B. vitiensis (Turrill), and B. lutea (Guillaumin). Kermadecia, very distinct from the four genera under present consideration, is again interpreted as a New Caledonian endemic.  相似文献   

17.
Sponges are the dominant invertebrates in many Antarctic communities, where they play a decisive structural function thanks to their abundance and large sizes. However, current knowledge on Antarctic sponges remains poor even with respect to basic aspects such as taxonomy. Here, we report on an Antarctic species of the genus Stylocordyla, which has been recorded for a long time under the name of the boreal S. borealis due to spicule and growth habit similarities. A thorough study of dense populations of the only Stylocordyla species known up to now from the eastern zone of the Weddell Sea as well as the re-examination of several specimens (including the type material) of S. borealis has allowed us to assess the variability of the boreal species and to confirm that the austral species is not S. borealis (Lovén, 1868) but a new species of Stylocordyla, different from the other congeners recorded from southern latitudes. The new species S. chupachups commonly dwells on horizontal or slighted sloped hard bottoms of the continental shelf of Weddell Sea, from 100 m to below 400 m depth, although the densest populations usually occur between 150 and 300 m. It is a pioneer species in areas that have been scoured by icebergs, and thus its presence may be considered an indicator of recent colonisation.  相似文献   

18.
Phytochemical composition of Hypericum genus has been investigated for many years. In the recent past, studies on the essential oils (EO) of this genus have been progressing and many of them have reported interesting biological activities. Variations in the EO composition of Hypericum species influenced by seasonal variation, geographic distribution, phenological cycle and type of the organ in which EO are produced and/or accumulated have also been reported. Although many reviews attributed to the characterization as well as biological activities of H. perforatum crude extracts have been published, no review has been published on the EO composition and biological activities of Hypericum species until recently (Crockett in Nat Prod Commun 5(9):1493–1506, 2010; Bertoli et al. in Global Sci Books 5:29–47, 2011). In this article, we summarize and update information regarding the composition and biological activities of Hypericum species EO. Based on experimental work carried out in our laboratory we also mention possible biotechnology approaches envisaging EO improvement of some species of the genus.  相似文献   

19.
One new species of Penicillium Link ex Gray nom. cons. prop. is described and illustrated. This species has been recovered from samples of sandy soil under pine trees. It differs from all species of the Genus described so far and is, therefore, considered and proposed as new taxon: Penicillium caerulescens n. sp.  相似文献   

20.
Cistus creticus L., an aromatic species from the Mediterranean area, contains various diterpenes bearing the labdane skeleton. The production of essential oil from this species has potential economic value, but so far, it has not been optimized. In order to contribute to a better knowledge of this species and to its differentiation, the morphological characters, volatile chemical composition and genetic data of two subspecies (C. creticus subsp. eriocephalus and C. creticus subsp. corsicus) were investigated. The leaf trichomes were studied using scanning electron microscopy. The chemical composition of Corsican essential oil (C. creticus subsp. corsicus) has been reported using GC, GC/MS and 13C NMR; the main constituents were oxygenated labdane diterpenes (33.9%) such as 13-epi-manoyl oxide (18.5%). Using plant material (54 samples) collected from 18 geographically distinct areas of the islands of Corsica and Sardinia, the basis of variation in the headspace solid-phase microextraction volatile fraction and an inter-simple sequence repeat genetic analysis were also examined. It was shown that the two subspecies of C. creticus differed in morphology, essential oil production, volatile fraction composition and genetic data.  相似文献   

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