首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
Clumping, pairing, and fusion of zoospores occur commonly in three isolates of Rhizophlyctis occanis sp. n., as well as in R. ingoldii Sparrow from the South Pacific islands and New Zealand. At present the fusions are interpreted to be gametic, but this interpretation has not been substantiated fully because it has not been possible so far to bring the fusion products to maturity and demonstrate conclusively that resting spores are sexually formed. The motile cells appear to be facultative. They may function as zoospores and develop directly into sporangial thalli or fuse to form young zygote-like thalli. In this respect they are very similar to those of some members of the Olpidiaceae and Synchytriaceae. The fusing cells lose their morphological identity as such in the process of fusion as in members of these families, and in this respect they are unlike most of those of the family Rhizidiaceae in which Rhizophlyctis is commonly classified. The fusions in R. occanis and R. ingoldii are strikingly similar to those in Karlingia dubia Karling, an operculate species, which indicates that Rhizophlyctis and Karlingia are closely related genera.  相似文献   

2.
Summary Several monocentric chytrid species of the generaPhlyctochytrium,Rhizidium,Chytridium,Chytriomyces andKarlingia were isolated on various substrata from soils of Oceania. Among these are two new species,Phlyctochytrium megastomum andRhizidium endosporangiatum. The former species is characterized chiefly by sporangia with an usually large apical, subapical, or a lateral exit orifice, the persistence of remnants of the pailla wall at the edge of the exit orifice, and by small zoospores. Rhizidium endosporangiatum is characterized at first primarily by predominantly spherical sporangia which develop 1 to 8 broad papillae. At maturity these papillae give them an angular shape. The exit papillae deliquesce at the tip, and through them protrude prominent arms of an endosporangium which expands and in which the zoospores usually swarm briefly. Willoughby's Chytridium parasiticum occurred abundantly as a parasite ofNowakowskiella sp.,Pythium sp., andPhytophthora sp. and developed epibiotic resting spores like those ofChytriomyces. Accordingly, this parasite is transferred to this genus and renamedChytriomyces willoughbyii because the nameparasiticum is preempted by the author's previously describedChytriomyces parasiticus.This study has been supported by a grant from the National Science Foundation, Washington, D.C.  相似文献   

3.
A previously published DNA barcode survey of red macroalgae in Australia revealed significant cryptic and overlooked diversity for the genus Rhodymenia with recognition of R. novahollandica, R. prolificans, R. stenoglossa, R. wilsonis and an additional four uncharacterized genetic species groups. Since that study, increased sampling effort in Australia has warranted reassessment and reinvestigation of the number of genetic species groups attributed to Rhodymenia and their respective taxonomic affiliations. Using molecular-assisted alpha taxonomy employing the DNA barcode (COI-5P), the present study resolved 188 Australian specimens in 12 genetic species groups assignable to the genus Rhodymenia. Four of these groups were attributed to the previously recognized species (above), whereas some collections from Lord Howe Island were attributed to the New Zealand species R. novazelandica, expanding its biogeographic range. The following seven genetic groups were inconsistent with existing species of Rhodymenia and established as novel taxa: R. compressa sp. nov., R. contortuplicata sp. nov., R. gladiata sp. nov., R. insularis sp. nov., R. lociperonica sp. nov., R. norfolkensis sp. nov. and R. womersleyi sp. nov. Although morphological and biogeographic features were adequate for distinguishing some species of Rhodymenia from Australia, DNA sequencing in combination with morphology and biogeography provided the most reliable means of identification.  相似文献   

4.
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   

5.
A new subfamily of ichneumon wasps, Labenopimplinae subfam. nov. (Ichneumonidae), is described from the Cenomanian Ola Formation of the locality Obeshchayushchiy, Magadan Region, Russian Far East. The subfamily is highly diverse morphologically and combines characters of the Labeninae and Pimplinae. It includes 11 new species described in five new genera: Labenopimpla rasnitsyni gen. et sp. nov., L. kasparyani sp. nov., Armanopimpla zherikhini gen. et sp. nov, Ramulimonstrum intermedium gen. et sp. nov., Rugopimpla vulgaris gen. et sp. nov., R. fallax sp. nov., R. angusticella sp. nov., R. macra sp. nov., R. matrona sp. nov., Micropimpla lucida gen. et sp. nov., and M. obscura sp. nov. Also described is a new monotypic genus, Tryphopimpla xoridoptera gen. et sp. nov., which combines characters of the Tryphoninae, Pimplinae, and Xoridinae and cannot be currently placed into any of the known subfamilies. The population of fossil ichneumon wasps at this locality is distinctly dominated by females.  相似文献   

6.
Eight species of the Strongylophthalmyiidae are reported from Papua New Guinea. Of these, five species (Strongylophthalmyia gigantica sp. nov., S. papuana sp. nov., S. rubella sp. nov., S. sedlaceki sp. nov. and S. shatalkini sp. nov.) are described as new to science. Strongylophthalmyia puncticollis Frey is recorded for the first time from Papua New Guinea. Faunistic remarks, a key to the species of the Strongylophthalmyia in Papua New Guinea and a world checklist are provided.  相似文献   

7.
分别基于波茎赤叉脉叶蝉Rakta sinuata sp. nov. 为模式种建立了赤叉脉叶蝉属Rakta gen. nov.,基于双突白叉脉叶蝉Albodikra bifida sp. nov. 为模式种建立了白叉脉叶蝉属Albodikra gen. nov.,进行了描记和绘图。虽然这两个属的后翅翅脉近似于小绿叶蝉族的特征,但此处将它们置于小叶蝉中的叉脉叶蝉族,并讨论了归族所依据的形态特征。  相似文献   

8.
9.
ABSTRACT

Pselaphotumulus Owens and Carlton, gen. nov., is described as the sixth genus in the tribe Pselaphini known from New Zealand. Three new species are described: Pselaphotumulus aorerei, sp. nov., Pselaphotumulus dubius, sp. nov. and Pselaphotumulus unus, sp. nov.. Three species, Pselaphus cavelli (Broun 1893), Pselaphus oviceps (Broun 1917) and Pselaphus urquharti (Broun 1917) are transferred to Pselaphotumulus, nov. combs. Lectotypes from type series in the New Zealand Broun Collection (Natural History Museum, London) are designated for these three species. Habitus photographs, distributional maps and line drawings of diagnostic characters are provided for each species. A key to species is provided. Searches of museum collections have not yielded representatives outside of New Zealand, suggesting that this is the first endemic genus in the tribe Pselaphini described from the New Zealand’s main islands, specifically, the South Island. Pselaphotumulus species exhibit restricted distribution patterns that approximately coincide with the Pacific/Indo Australian Plate boundary.  相似文献   

10.
The genus Entactinosphaera Foreman, 1963 is revised; it is shown to combine seven different genera, which are distinguished by morphological characters and belong to three orders of two radiolarian classes: the class Sphaerellaria, order Entactiniata (Bientactinosphaera, Entactinosphaera, Helioentactinia, Radiobisphaera), and class Spumellaria, orders Cancelliata (Retientactinosphaera, Magnisphaera) and Spongiata (Spongentactinia). New radiolarian taxa from the Middle Frasnian-Lower Famennian of the Timan-Pechora Basin and from the Lower Famennian of the Polar Ural Mountains, Russia, are described: Retientactinosphaera gen. nov., R. magnifica sp. nov., and R. clavata sp. nov.  相似文献   

11.
Fourteen species of lingulate brachiopods are documented from allochthonous limestone blocks of the Murrawong Creek Formation in the southern New England Fold Belt, northeastern New South Wales, Australia. The fauna includes Treptotreta jucunda Henderson and MacKinnon 1981, Treptotreta sp. cf. T. sp. nov. Henderson 1992, Amictocracens teres Henderson and MacKinnon 1981, Stilpnotreta magna Henderson and MacKinnon 1981, Anabolotreta tegula Rowell and Henderson 1978, Neotreta orbiculata Koneva 1990, Linnarssonia sp., Linnarssonia sp. cf. L. ophirensis (Walcott 1912), Pegmatreta clavigera sp. nov., Acrothele subsidua (White 1874), Micromitra sp. cf. M. modesta (Lochman 1940), Micromitra sp. Henderson 1992, Lingulella sp. A Henderson 1992, and Kyrshabaktella certa Koneva 1986.

The associated trilobite assemblages indicate a medial Middle Cambrian age for the blocks, and the stratigraphic ranges of several of the lingulate species have been extended. The fauna displays biogeographic links at the specific level with northeastern and southeastern Australia, New Zealand, Antarctica, North America, Kazakhstan, Siberia, and Britain; the strongest links (four species in common) are with the Georgina Basin in northeastern Australia and the Tasman Formation in New Zealand.  相似文献   

12.
A new genus, Rovnocapnia gen. nov., with new species R. atra sp. nov. and R. ambita sp. nov., from the family Capniidae, and a new genus and species Palaeoleuctra acuta gen. sp. nov., from the family Leuctridae, of the suborder Nemourina (Euholognatha), are described from Late Eocene Rovno amber. Familial assignment of one additional specimen (suborder Perlina, infraorder Perlomorpha (Systelognatha)), represented by a nymphal skin, is obscure due to its incomplete preservation.  相似文献   

13.
New grylloblattid insects (Grylloblattida) are described from the Grès à Voltzia of the Vosges (Anisian of Alsace and Lorraine, France): Chauliodites anisicus, sp. nov. (Chaulioditidae), Palaeomesorthopteron pullus gen. et sp. nov. (Mesorthopteridae), Megakhosarodes vosgesicus sp. nov. (Megakhosaridae), Dorniella elcanoides sp. nov., D. apectinata sp. nov., D. diluta sp. nov., D. ovalis sp. nov., Baharellinus umbrosus sp. nov. Embigryllus shcherbakovi gen. et sp. nov., and Vosgesopterum arzvillerensis gen. et sp. nov. (Blattogryllidae).  相似文献   

14.
New conodont species of the genus Polygnathus (P. krutoensis sp. nov., P. makhlinae sp. nov., P. menneri sp. nov., P. obruchevae sp. nov.) are described from the Evlanovian-Livnian (Upper Devonian) deposits of the Voronezh Anteclise (central regions of the Rassian platform). The ontogenetic series of the new species are presented.  相似文献   

15.
New stonefly species of the family Palaeonemouridae, Palaeonemoura issadensis, sp. nov., Palaeotaeniopteryx laeta, sp. nov., and P. triternata, sp. nov., are described from the Tatarian (Upper Permian) locality of Isady (Severodvinian Stage of the Vologda Region).  相似文献   

16.
The genus Rhizomastix is a poorly known group of amoeboid heterotrophic flagellates living as intestinal commensals of insects, amphibians or reptiles, and as inhabitants of organic freshwater sediments. Eleven Rhizomastix species have been described so far, but DNA sequences from only a single species have been published. Recently, phylogenetic analyses confirmed a previous hypothesis that the genus belongs to the Archamoebae; however, its exact position therein remains unclear. In this study we cultured nine strains of Rhizomastix, both endobiotic and free‐living. According to their light‐microscopic morphology and SSU rRNA and actin gene analyses, the strains represent five species, of which four are newly described here: R. bicoronata sp. nov., R. elongata sp. nov., R. vacuolata sp. nov. and R. varia sp. nov. In addition, R. tipulae sp. nov., living in the intestine of crane flies, is separated from the type species, R. gracilis. We also examined the ultrastructure of R. elongata sp. nov., which revealed that it is more complicated than the previously described R. libera. Our data show that either the endobiotic lifestyle of some Rhizomastix species has arisen independently from other endobiotic archamoebae, or the free‐living members of this genus represent a secondary switch from the endobiotic lifestyle.  相似文献   

17.
In a taxonomic/phylogenetic study of the genus Lenormandia, several species were found to differ significantly from the type species, L. spectabilis Sonder, in apical morphology, blade‐surface pattern, medullary construction, the presence of pseudopericentral cells, and the position of reproductive structures. These species constitute two groups that differ morphologically, a finding largely supported by analysis of 18S rRNA sequences, as reported previously. The two putative Lenormandia species from New Zealand, along with two previously undescribed species also from New Zealand, comprised one such group, designated here by the new genus name Adamsiella L.E. Phillips et W.A. Nelson, gen. nov. and including A. melchiori L.E. Phillips et W.A. Nelson, sp. nov., A. lorata L.E. Phillips et W.A. Nelson, sp. nov., A. angustifolia (Harvey) L.E. Phillips et W.A. Nelson, comb. nov., and A. chauvinii (Harvey) L.E. Phillips et W.A. Nelson comb. nov. Adamsiella differs from Lenormandia by incurved apices, a chevron surface pattern, and reproductive structures on dorsi‐ventrally flattened apically incurved polysiphonous branchlets usually produced at the margins. Two species endemic to Australia formed the second group designated by the resurrected generic name Epiglossum and also characterized by a strongly incurved apex and chevron surface pattern but with reproductive structures produced on terete polysiphonous branchlets found either on the midrib or elsewhere on the blade surface but not the margins. Epiglossum contains E. smithiae (J.D. Hooker et Harvey) Kützing and E. proliferum (C. Agardh) L.E. Phillips, comb. nov.  相似文献   

18.
Cumaceans (Crustacea: Peracarida) belonging to the family Bodotriidae collected between 206 and 3680 m depth, during the French campaigns BIOCAL and BIOGEOCAL in waters of New Caledonia, KARUBAR in Indonesia and BORDAU 1 around Fiji were studied. The 93 specimens belonging to this family were assigned to 11 species, ten of them new to science, namely Cyclaspis variosculpta sp. nov., Cyclaspis richeri sp. nov., Cyclaspis dictyota sp. nov., Cyclaspis decora sp. nov., Cyclaspis magna sp. nov., Cyclaspoides erugatus sp. nov., Alticuma? ectyphum sp. nov., Apocuma pacificum sp. nov., Hypocuma fragosum sp. nov. and Bathycuma coremium sp. nov. The genera Cyclaspoides and Hypocuma are recorded for the first time from the Pacific Ocean. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society, 2008, 152 , 227–254.  相似文献   

19.
A new ammonite genus Riasanella is described from the Ryazanian Stage of the Russian Platform (type species R. rausingi sp. nov.). The new species R. plana sp. nov., R. olorizi sp. nov., and R. riasanitoides sp. nov. are described. These species come from the lower, strongly condensed beds of the Riasanites rjasanensis Zone of the Moscow Region. The upper subzone of this zone in the Ryazan Region contains specimens of Riasanella, identified in open nomenclature. The new genus is assigned to the family Himalayitidae; one of its species is a possible ancestor of Riasanites Spath.  相似文献   

20.
Two species of Phycodrys, Phycodrys quercifolia (Bory) Skottsberg and Phycodrys profunda E.Y.Dawson were previously recorded from New Zealand. However, an examination of Phycodrys collections from the New Zealand region showed that all were morphologically different from P. quercifolia (Type locality: the Falkland Islands) and P. profunda (Type locality: CA, USA). RbcL sequence analyses established that the New Zealand Phycodrys species formed a natural assemblage within the genus, consisting of three new species: P. novae-zelandiae sp. nov., P. franiae sp. nov. and P. adamsiae sp. nov. Phycodrys novae-zelandiae is the largest of the three, up to 20 cm in height, with a distinct midrib and multicellular, opposite to subopposite lateral macroscopic veins. It has entirely monostromatic blades except near the midrib and veins, and its procarp contains a three-celled sterile group one (st1) and a one-celled sterile group two (st2). Phycodrys franiae was previously treated as a cryptic species among herbarium collections of P. ‘quercifolia’. It is smaller (4–11 cm high) with weakly developed midribs and veins, the blade is tristromatic throughout, except at the growing margins, and the procarp consists of a four-celled st1 and a two–three-celled st2. Phycodrys adamsiae, previously reported as P. profunda, is a small decumbent or prostrate plant, 1–8 cm long, with a midrib and inconspicuous lateral veins. The blades are tristromatic with serrated margins, two–four-celled surface spines and multicellular marginal holdfasts that differ from those of Californian specimens. The tetrasporangia are borne on marginal bladelets. Phylogenetic analyses place the New Zealand species in a separate group that is distantly removed from most other Phycodrys species.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号