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1.
A new potentially ichthyotoxic dinoflagellate genus, Takayama de Salas, Bolch, Botes et Hallegraeff gen. nov., is described with two new species isolated from Tasmanian (Australia) and South African coastal waters: T. tasmanica de Salas, Bolch et Hallegraeff, sp. nov. and T. helix, de Salas, Bolch, Botes et Hallegraeff, sp. nov. The genus and two species are characterized by LM and EM of field samples and laboratory cultures as well as large subunit rDNA sequences and HPLC pigment analyses of several cultured strains. The new Takayama species have sigmoid apical grooves and contain fucoxanthin and its derivatives as the main accessory pigments. Takayama tasmanica is similar to the previously described species Gymnodinium pulchellum Larsen, Gyrodinium acrotrochum Larsen, and G. cladochroma Larsen in its external morphology but differs from these in having two ventral pores, a large horseshoe‐shaped nucleus, and a central pyrenoid with radiating chloroplasts that pass through the nucleus. It contains gyroxanthin‐diester and a gyroxanthin‐like accessory pigment, both of which are missing in T. helix. Takayama helix has an apical groove that is nearly straight while still being clearly inflected. A ventral pore or slit is present. It has numerous peripheral, strap shaped, and spiraling chloroplasts with individual pyrenoids and a solid ellipsoidal nucleus. The genus Takayama has close affinities to the genera Karenia and Karlodinium.  相似文献   

2.
New species of the obligately marine Thraustochytriaceae Sparrow were discovered in subantarctic and antarctic waters of the southeastern Indian Ocean, the southwestern Pacific Ocean, and the antarctic Ross Sea during two cruises of the research vessel USNS ELTANIN. The life cycles of four species of Thraustochytrium in seawater-pollen and/or seawater-brine shrimp larvae cultures are described. Thraustochytrium antarcticum sp. nov. develops sporangia that may proliferate from a single basal rudiment. Flagellated zoospores are liberated from the sporangium upon complete disintegration of the sporangial wall at maturity. Thraustochytrium rossii sp. nov. and T. kerguelensis sp. nov. are both similar in that they develop sporangia that may proliferate from more than one basal rudiment. The latter species releases flagellated zoospores upon complete disintegration of the sporangial wall, but the former species liberates a mass of individually immobile zoospores from the sporangium. These remain quiescent for several hours before they swim away one after another. The protoplast of Thraustochytrium amoeboidum sp. nov. leaves the sporangium through a pore as an amoeboid body which then gives rise to nonflagellated amoebospores by successive bipartitioning. Laterally biflagellate thraustochytrioid zoospores were also observed, but the way in which they are formed remains to be determined. Zoosporic and aplanosporic phycomycetes were recovered from water samples collected in the Subtropical, Subantarctic, and Antarctic Zones of the Southern Ocean. Highest numbers of phycomycete propagules were found in antarctic waters near the Antarctic Convergence during ELTANIN's Cruise 51. In the Subtropical and Subantarctic (but not in the Antarctic) Zones fungal population densities increased with proximity to continents or islands. At each station where phycomycetes were recovered, highest numbers of propagules were generally found in the surface layers (25–250 m) of the ocean below the photic zone (lower limit 30–60 m). This peculiar distribution may indicate that phycomycetes are engaged in decomposing substances derived from the photic zone.  相似文献   

3.
4.
Investigations on calcareous dinoflagellates from surface sediments from the Mediterranean Sea revealed 14 species, including one new genus and four previously undescribed species: Calciodinellum levantinum sp. nov., Calciodinellum elongatum nov. comb., Lebessphaera urania gen. nov. et sp. nov., and Scripp‐ siella triquetracapitata sp. nov. Furthermore, Fuettererella cf. tesserula, so far only known from the fossil record, was found. The cyst–theca relationships of C. levantinum and C. elongatum are given, based on strains established from water samples of the Mediterranean Sea and the Atlantic Ocean. This study gives an insight into the importance of the modern Mediterranean Sea as an unique region concerning calcareous cyst producing dinoflagellates.  相似文献   

5.
Abstract Three new species of the family Formicidae were discovered in Xishuangbanna Nature Reserve of Southern Yunnan, China, i.e. Emeryopone melaina sp. nov., Myopias conicara sp. nov. and Myrmoteras cuneonodum sp. nov. Emeryopone Forel and Mymoteras Forel are new record genera in China. Myopias Roger is recorded in mainland of China for the first time.  相似文献   

6.
Toxin analysis of 15 species of Kareniaceae revealed the presence of karlotoxin, KmTx 2, in only a single species (Karlodinium veneficum) but with variable activity in strains from the Swan (KmSwanTx 2‐1, 2.1 pg · cell?1; and KmSwanTx 2‐2, 0.53 pg · cell?1), Huon (KmHuonTx 2, 0.86 pg · cell?1), and Derwent rivers (<0.001 pg · cell?1) in Australia. A newly isolated Southern Ocean species, Karlodinium conicum, contained a novel poorly hemolytic karlotoxin analogue (KmconicumTx, 2.8 pg · cell?1). The hemolytic potency (HD50%) of the Australian karlotoxins were as follows: KmSwanTx 2‐1 (65.9 ± 4.8 ng) and KmSwanTx 2‐2 (63.4 ± 3.7 ng), KmHuonTx 2 (343 ± 4.9 ng), and KmconicumTx (>4,000 ng). Species from the closely related genera Takayama (T. helix, T. tasmanica, T. tuberculata), Karenia (K. asterichroma, K. brevis, K. mikimotoi, K. papilionacea, K. umbella), and Karlodinium (Ka. australe, Ka. antarcticum, Ka. ballantinum, Ka. corrugatum, Ka. decipiens) were all consistently negative for karlotoxin production. Brevetoxin (PbTx) was only detected in K. brevis, and hemolytic activity was only observed in Ka. veneficum strains.  相似文献   

7.
Meicai Wei 《Insect Science》1997,4(2):112-120
Abstract Filixungulia gen. nov. belonging to Allantini and three new species, Filixungulia dbo-clypea sp. nov., F. crassitarsata sp. nov., and Macremphytus crasskornis sp. nov. are described from China. A synoptic key to the genera with three cubital cells in front wing of Allantini is proposed. The genera Tritobrachia Enderlein, Macremphytus MacGillivray and Linomorpha Malaise with Tritobrachia tenuicornis Enderlein are new records from China. Linamorpha flava (Takeuchi) is a new combination transferred from Emphytus Klug.  相似文献   

8.
Boyi Zheng 《Insect Science》1996,3(3):229-242
Abstract This paper reports five new larval mite species belonging to the genus Leptus Latreille 1796, that is, L. hupingshunicus sp. nov., L. shimenensis sp. nov., L. brachypodos sp. nov., L. dolichopodos sp. nov., and L. sulciscutus sp. nov. All species were collected by using the Malaise Trap from Mt. Hupingshan, Shimen County, Hunan Province, China.  相似文献   

9.
《Harmful algae》2011,10(6):557-562
Two species of Kareniaceae, Karlodinium veneficum (Swan and Huon River isolates) and Karlodinium conicum, and their respective purified karlotoxins (KmTx), were investigated for ichthyotoxicity on larval sheepshead minnow. Two non-karlotoxin producing species, Karenia mikimotoi and Karlodinium ballantinum were also tested. Algal treatments included live and lysed cells (homogenized and CuSO4 treated) with fish mortalities observed from lysed Ka. veneficum and Ka. conicum but none observed from K. mikimotoi and Ka. ballantinum. The variance in ichthyotoxicity between live and lysed cells of Ka. veneficum (Swan and Huon River) and Ka. conicum (Southern Ocean) confirm that toxin is cell bound and ichthyotoxicity increases upon lysis. Ichthyotoxic blooms of Ka. veneficum in situ in the Swan River, Western Australia and Chesapeake Bay, Maryland, USA are unrelated to algal cell density as mortality was observed with low densities. In laboratory treatments, no fish mortalities were observed upon exposure to live intact cells of all four species at algal concentrations up to 2.5 × 105 cells/mL in replete nutrient growth conditions. Lysed low density (3 × 104 cells/mL) Ka. veneficum (Swan and Huon River) grown under P-limited nutrients caused quicker fish mortality than those cultured in replete nutrient conditions. Pure toxin isolated from Ka. veneficum (Swan and Huon River) and Ka. conicum (Southern Ocean) were toxic to sheepshead minnow larvae, with the lethal dose lowest for KmHuonTx 2 (508.2 ng/mL), followed by KmSwanTx 2-1 (563.2 ng/mL), and KmconicumTx (762.4 ng/mL).  相似文献   

10.
Nephrostrobus cliffwoodensis gen. et sp. nov., Nephrostrobus bifurcatus sp. nov., and Rhombostrobus cliffwoodensis gen. et sp. nov. are described based on anatomical studies of seed cone fragments from the Upper Cretaceous Magothy Formation of New Jersey. These species belong to the Taxodiaceae. As in Sequoia, Sequoiadendron. and Metasequoia, the vascular strands supplying the scale and bract in Nephrostrobus are about equal. These vascular strands are arranged in a reniform pattern resembling that found in Metasequoia, but the orientation differs by 180 degress. Nephrostrobus cliffwoodensis and Nephrostrobus bifurcatus differ from each other in the branching of the complex trace and associated resin canals. Rhombostrobus cliffwoodensis resembles Cunninghamia in the arrangement of vascular strands and associated resin canals in its bract-scale complexes. However, the relative amount of bract and ovuliferous scale making up the complex is more like that in Sequoia. This combination of cone features does not occur in any of the extant genera. Nephrostrobus and Rhombostrobus are not considered to be ancestral to any of the extant taxodiaceous genera, but are extinct members of an ancestral complex from which the extant genera were derived.  相似文献   

11.
Three new taxa are described: Dolyella hawaiiensis var. clavata var. nov., Cottoniella triseriata sp. nov., and Taenioma dotyi sp. nov. A modified characterization of the genus Cottoniella is given, and certain critical distinctions between the species are presented. Taenioma dotyi is distinctive in the increased width of the determinate branches resulting from division of the flanking cells.  相似文献   

12.
Abstract Three new species of the genus Diostracus are described from Southwest China, namely D. albuginosus sp. nov., D. lamellatus sp. nov. and D. dicercaeus sp. nov. The type specimens are deposited in the author's collection.  相似文献   

13.
Abstract The present paper describes 2 new genera, viz:Dimelaphis Zhang, gen. nov and Siciforda Zhang, gen. nov, 5 new species viz: Chaetogeoica ulmidrupa Zhang sp. nov, D. obtusifalcata Zhang, sp. nov., Forda auralenta Zhang et Qiao, sp. nov., F. multicoma Zhang, sp. nov. and S. sexiarticulata Zhang, sp.nov. and 1 new subspecies Paracletus cimiciformis zhanhuanus Zhang, ssp. nov. from China. All type specimens are deposited in the Institute of Zoology, Academia Sinica.  相似文献   

14.
Abstract This paper describes four new species of the genus Tachytrechus Haliday 1851, from Guizhou in southwestern China, namely, T. absarista Wei, sp. nov., T. crysus Wei, sp. nov, T. crypsusoideus Wei, sp. nov. and T. modestus Wei, sp. nov. A key to all 9 named species is given. The type specimens are deposited in the author's collection.  相似文献   

15.
Abstract: Bulk sampling of phosphate‐rich horizons within the British Coniacian to Campanian (Upper Cretaceous) yielded very large samples of shark and ray teeth. All of these samples yielded teeth of diverse members of the Carcharhiniformes, which commonly dominate the fauna. The following species are recorded and described: Pseudoscyliorhinus reussi ( Herman, 1977 ) comb. nov., Crassescyliorhinus germanicus ( Herman, 1982 ) gen. nov., Scyliorhinus elongatus ( Davis, 1887 ), Scyliorhinus brumarivulensis sp. nov., ?Palaeoscyllium sp., Prohaploblepharus riegrafi ( Müller, 1989 ) gen. nov., ?Cretascyliorhinus sp., Scyliorhinidae incertae sedis 1, Scyliorhinidae incertae sedis 2, Pteroscyllium hermani sp. nov., Protoscyliorhinus sp., Leptocharias cretaceus sp. nov., Palaeogaleus havreensis Herman, 1977 , Paratriakis subserratus sp. nov., Paratriakis tenuis sp. nov., Paratriakis sp. indet. and ?Loxodon sp. Taxa belonging to the families ?Proscylliidae, Leptochariidae and Carcharhinidae are described from the Cretaceous for the first time. The evolutionary and palaeoecological implications of these newly recognised faunas are discussed.  相似文献   

16.
Abstract This is the first report about family Homocaligidae from China. Two new species, Annerossella lii sp. nov. and Homocaligus erassipus sp. nov., living on Eichhornia crassipes (Mart.) from Fujian Province are described.  相似文献   

17.
An approximately 1400‐bp region of the 16S rRNA gene was sequenced for 10 polar or near‐polar strains putatively placed in the Oscillatorialean genera Oscillatoria, Phormidium, and Lyngbya obtained from the University of Toronto Culture Collection to assess phylogenetic relationships. The strains were also examined for thylakoid structure and cell division type with TEM as well as traditional morphology with LM. Phylogenetic trees constructed using parsimony, distance, and maximum likelihood methods were similar in topology. If the original epithets applied to the sequenced strains (both polar and those from GenBank) were used, it was clear that taxa were not monophyletic. However, using the revised taxonomic system of Anagnostidis and Komárek, we were able to reassign these strains to their current correct taxa (species, genus, and family). When these assignments were made, it was determined that the molecular sequence data analyses were congruent with morphology and ultrastructure. Nine of the polar strains were found to be new species, and eight were described as such: Arthronema gygaxiana Casamatta et Johansen sp. nov., Pseudanabaena tremula Johansen et Casamatta sp. nov., Leptolyngbya angustata Casamatta et Johansen sp. nov., Phormidium lumbricale Johansen et Casamatta sp. nov., Microcoleus glaciei Johansen et Casamatta sp. nov., Microcoleus rushforthii Johansen et Casamatta sp. nov., Microcoleus antarcticus Casamatta et Johansen sp. nov., Microcoleus acremannii Casamatta et Johansen sp. nov. Some genera (Leptolyngbya and Microcoleus) were clearly not monophyletic and require future revision.  相似文献   

18.
LATE PRECAMBRIAN TRACE FOSSILS FROM NEW SOUTH WALES   总被引:2,自引:0,他引:2  
Seven trace-fossil species are described from the upper part of the Torrowangee Group (Upper Proterozoic) of western New South Wales, and a variety of other traces are illustrated. A few forms occur in the Fowlers Gap Beds, and a more diverse and abundant fauna is recorded from the stratigraphically higher Lintiss Vale Beds. Virtually all the traces are preserved in the plane of bedding, as semi-reliefs. The named trace fossils all come from the Lintiss Vale Beds, and are as follows: Planolites ballandus sp. nov., Planolites? sp., Cochlichnus serpens sp. nov., Gordia? sp., Torrowangea rosei gen. et sp. nov., Phycodes? antecedent sp. nov., and Curvolithus? davidis sp. nov. Three of these species are regarded as feeding burrows (endogene), and are thought to represent the activity of infaunal, worm-like deposit feeders. Others may be either feeding burrows or crawling trails. There are also a few impressions which seem to be rest marks. A discussion of the significance of the trace-fossil occurrences is presented.  相似文献   

19.
Three new dinoflagellate species, Karenia papilionacea sp. nov., Karenia selliformis sp. nov., and Karenia bidigitata sp. nov., were compared with the toxic species Karenia mikimotoi (Miyake & Kominami ex Oda) G. Hansen & Moestrup, Karenia brevis (Davis) G. Hansen & Moestrup, and Karenia brevisulcata (Chang) G. Hansen & Moestrup using the same fixative. Distinguishing morphological characters for the genus Karenia included a smooth theca and a linear apical groove. The new species can be distinguished on the basis of morphological characters of vegetative cells that include the location and shape of the nucleus; the relative excavation of the hypotheca; the characteristics of apical and sulcal groove extensions on the epitheca; the cellular shape, size, and symmetry; the degree of dorsoventral compression; and the presence of an apical protrusion or carina. Species with pronounced dorsoventral compression swim in a distinctive fluttering motion. An intercingular tubular structure traversing the proximal and distal ends of the cingulum is common to the species of Karenia, Karlodinium micrum (Leadbeater & Dodge) J. Larsen, Gymnodinium pulchellum J. Larsen, and Gyrodinium corsicum Paulmier. Molecular phylogenetic analyses of rDNA sequence alignments show that the new species are phylogenetically distinct but closely related to K. mikimotoi and K. brevis.  相似文献   

20.
Abstract This paper deals with twenty-nine species of Coleophora salicorniae group of Coleophoridae. Among them, twelve species (Coleophora lativalva sp. nov., C. ossaedeaga sp. nov., C. pendulivalvula sp. nov., C. novisqualorella sp. nov., C. capitargentella sp. nov., C. curvidentatella sp. nov., C. dorsiproducta sp. nov., C. harbinensis sp. nov., C. xinjiangensis sp. nov…C. cuprea sp. nov., C. pallidiptera sp. nov. and C. resupina sp. nov.) are described as new to science and fifteen species are newly recorded from China. Carpochena halostachyos Falkovitsh is proposed as a synonym of Coleophora plicipunctella Chrètien. Genitalia of new species are illustrated and females of Coleophora armeniae Baldizzone et Patzak, C. carchara Falkovitsh and C. sequens Falkovitsh are described for the first time. A key to Chinese species of Coleophora salicorniae group is given.  相似文献   

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