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Five taxa already in the literature are here removed from Chydorus to their own genus Ephemeroporus, and two new species — E. acanthodes and E. archboldi — are described, with E. acanthodes being designated the type species of the genus. These taxa, plus at least nine undescribed species and others undoubtedly waiting to be sorted out, constitute a tightly circumscribed group of species morphologically. The first two species described — E. barroisi and E. poppei — are nomina dubia for the present, as no specimens exist from the original collections, nor are any available from the type localities or reasonably close thereto. E. hybridus from Brazil has been characterized in greater detail through the availability of specimens from the type series, which has enabled one of the species in the E. hybridus group from North America to be judged conspecific with reasonable certainty. E. tridentatus, from Brazil, has been restored as a valid species, and the highly distinctive E. phintonicus from Sardinia and Algeria constitutes the seventh species in the genus. Chydorus nitidulus and Chydorus tilhoi, which have been suggested to be members of the barroisi complex, are not. What are presently called E. barroisi and E. hybridus, except for E. hybridus, sens. str., each consists of a cluster of species sharing the same number of teeth on the labrum and shell. Because of their wide, distribution, abundance, and frequency of occurrence, especially in South Asia, the species in the E. barroisi group will be especially meaningful to sort out.  相似文献   

3.
Taxonomy of the genus Leveillula has long been considered as a challenge in powdery mildew systematics. The rDNA diversity has recently been used for phylogenetic analysis of several specimens of the genus Leveillula. In the present study, additional rDNA ITS sequences are provided and a new phylogenetic analysis is carried out aiming at a better understanding of the genetic diversity in the genus Leveillula. New analyses confirmed that L. taurica is unique in the genus, as it exhibits an intraspecific gene sequence diversity considerably higher than in other species. In several cases L. taurica s. lat. on a certain host plant species has a sequence different from L. taurica on other host plants. Moreover, DNA data indicated different lineages among L. taurica specimens which were hardly distinguishable by morphology. More than one genotype occurring on a single host is sometimes possible. According to these results, several races such as Leveillula on Artemisia, Acroptilon, Onobrychis, are molecularly well characterized. While there is enough molecular evidence to delimit such races as independent taxa, clear morphological delimitations between these new and already published taxa are very difficult or even impossible. However, ecological features, and above all, host specificity for biotrophic fungi such as powdery mildew, would be a good criterion to discriminate cryptic taxa along with rDNA sequences. In fact, many collections of Leveillula strains on different hosts show their own type of conidial morphology, which is usually consistent for a strain on a single host species. Hence, we have proposed to describe new species for Leveillula on some host plants such as Artemisia, Acroptilon, Echinops and Onobrychis.  相似文献   

4.
Deep-sea smelts (Argentiniformes: Microstomatidae, Bathylaginae) from the Miocene of Far East Russia (Sakhalin and Urup islands) are described. The specimens described belong to four taxa, one of which is assigned to a new species of the genus Leuroglossus. Like Recent smoothtongues, the new species has thickened medial rays in the caudal fin. The small number of abdominal vertebrae makes the new species similar to the extant southern smoothtongue L. stilbius, which occurs along the eastern coasts of the Pacific Ocean. The new species differs from extant smoothtongues in the short snout, which is not longer than the orbit. Phylogenetic analysis of morphological features of the new species, using a matrix of characters of living deepsea smelts, shows that it occupies a basal position in the genus Leuroglossus. Three other extinct taxa cannot be reliably classified below the level of the subfamily Bathylaginae or tribe Bathylagini because of insufficient preservation of available specimens. The new records of deep-sea smelts in Far East Russia show that this fish subfamily was widespread and highly morphologically differentiated in the Neogene.  相似文献   

5.
Leaf undulation is used as a diagnostic feature in the taxonomy of different taxa of the Epipactis (Orchidaceae) genus. It is considered a specifically important trait, apart from the column (gynostemium) structure, in the identification of E. muelleri. However, leaf undulation is a common developmental phenomenon in various plants, including orchids, thus the main goal of the research presented was to validate the usefulness of this feature in Epipactis taxonomy. In the course of this study, the leaf structure of six Epipactis species was analyzed, i.e., E. albensis, E. atrorubens, E. helleborine, E. muelleri, E. palustris and E. purpurata. The leaf margin outline and the cellular pattern of the leaf surface, as well as the presence of papillae, were examined in detail. The results obtained showed that in all taxa analyzed, representing different groups of the Epipactis genus, leaf undulation was present. The phenomenon was related to leaf blade development and the local differential growth of leaf sectors rather than to the taxonomic position of the species. Therefore, leaf undulation studied in Helleborines does not have a diagnostic value as a non-programmed intrinsic feature and should not be applied to taxa identification. The valid trait in Epipactis classification (including E. muelleri) is the column structure.  相似文献   

6.
The marine benthic brown algae of the north coast of Papua New Guinea (mainly from Madang province) are documented, based on collections made by the first author, between 1980 and 1990. All records [34 identified taxa (+Sargassum spp.)] are listed with bibliographic, taxonomic, nomenclatural and biogeographical notes. The specimens belonging to the genus Dictyota are identified according to recent species definitions. D. magneana De Clerck et Coppejans is described as new to science. Only some representatives of the genus Sargassum have been identified to species level. The phaeophycean flora of the north coast is very similar to that of the south coast (Port Moresby area); nevertheless some differences can be observed.  相似文献   

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The Eupteryx aurata group is characterised by several features, primarily by colouration and aedeagus morphology. It is distributed mainly in Europe, with some species also in Asia and one species perhaps in North Africa. At least one species is introduced in North America. Until now 12 taxa were known. Two new species, Eupteryx divulsa from central Italy and Eupteryx oscorum from central and southern Italy, are described in this paper. Eupteryx petasitidis Ferrari, 1882, described as Eupteryx carpini petasitidis and later synonymised with Eupteryx atropunctata (Goeze, 1778), is reestablished on species level and redescribed including genital morphology. Ten taxa of the species group are studied in relation to their morphological and molecular characters. The colouration, aedeagus, and pygofer appendage are figured for all of these taxa. Molecular study showed that the E. aurata group is monophyletic. The little or moderate distances in sequences (below 6.0% for mtDNA and up to 2.5% for nuclear ITS2) between the different taxa of the E. aurata group and incongruence of genetic signals from mtDNA and nuclear DNA could be the result of incomplete lineage sorting in young species and/or hybridisation and introgression of DNA among taxa. Of particular importance in this study is material from Italy, a peripheral region in relation to the distribution of the species group and due to its geomorphological features favouring isolation and speciation. A distribution map for the E. aurata species group in Italy and an identification key for all 15 taxa of the aurata group are given. Phylogenetic relationships within the aurata group are discussed in relation to morphological, molecular, ecological, and zoogeographic aspects.  相似文献   

9.
A taxonomic study of poroid Asian species in the Auriculariales was conducted using phylogenetic and morphological methods. Phylogenetic analyses based on the LSU and ITS regions reveal that Elmerina was a polyphyletic genus. Moreover, E. hexagonoides collected from Malaysia and “E. hexagonoides” from Japan formed two distinct clades within a well-supported larger clade with Protomerulius caryae. These taxa comprise a different lineage from the type species of both Protomerulius and Protodaedalea, and we conclude that they are members of the genus Aporpium. The phylogenetic position of E. cladophora (type species of Elmerina) is still unclear, and we retain Aporpium and Protodaedalea as genera distinct from Elmerina. Aporpium strigosum sp. nov. is described to represent Japanese specimens misidentified as E. hexagonoides. Aporpium is characterized by resupinate to sessile basidiocarps, tough-fleshy to leathery context, poroid hymenophore, dimitic hyphal systems with unbranched skeletal hyphae, clavate to pyriform probasidia, and ellipsoid to cylindrical or allantoid basidiospores. Aporpium strigosum is similar to A. hexagonoides, but can be differentiated by the ochraceous to straw-colored basidiocarps, strigose pileus surface with long and stiff hairs, and the larger pores, basidia, and basidiospores.  相似文献   

10.
The fossil cercopithecoid material from South Africa has been reviewed according to sites and species. The 722 specimens considered comprise 6 genera including 16 taxa and come from 16 sites. Aspects of taxonomic controversy and interest are discussed. In particular, the Parapapio material from Makapansgat has been re-evaluated and the taxonomy of the genus Simopithecus is reconsidered. A number of proposals are put forward. Four new specimens from Makapansgat and one from Sterkfontein are described; a previously partially described specimen from Taung is re-described in detail.  相似文献   

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Eucalyptus gomphocephala (tuart) is a tree native to the southwest coast of Western Australia, where, in some areas, there is a significant decline in the health of tuart. Botryosphaeriaceous taxa have been isolated as endophytes and canker pathogens from numerous hosts in many parts of the world and have been implicated in the decline of E. gomphocephala. In the present study, endophytic fungi were isolated from a wide variety of native woody plant species (Acacia cochlearis, A. rostellifera, Allocasuarina fraseriana, Agonis flexuosa, Banksia grandis, E. gomphocephala, E. marginata and Santalum acuminatum), at two locations in native E. gomphocephala woodland; a site in decline at Yalgorup National Park and a healthy site at Woodman Point Regional Park. Of the 226 isolates obtained, 154 were botryosphaeriaceous taxa, 80 % of which were found to be Neofusicoccum australe, isolated from all hosts at both collection sites. Four new species are described, Dothiorella moneti, Dothiorella santali, Neofusicoccum pennatisporum, and a species belonging to a genus only recently included in the Botryosphaeriaceae, Aplosporella yalgorensis. The other species isolated were Botryosphaeria dothidea on the new hosts A. rostellifera, A. cochlearis and E. marginata and Dichomera eucalypti, on the new host E. marginata. None of the new species formed lesions on excised stems of their host species, E. gomphocephala, or a common plantation species, E. globulus. However, Neofusicoccum australe formed lesions on excised stems of E. globulus and E. gomphocephala.  相似文献   

13.
Coccodiella is a genus of plant-parasitic species in the family Phyllachoraceae (Phyllachorales, Ascomycota), i.e., tropical tar spot fungi. Members of the genus Coccodiella are tropical in distribution and are host-specific, growing on plant species belonging to nine host plant families. Most of the known species occur on various genera and species of the Melastomataceae in tropical America. In this study, we describe the new species C. calatheae from Panama, growing on Calathea crotalifera (Marantaceae). We obtained ITS, nrLSU, and nrSSU sequence data from this new species and from other freshly collected specimens of five species of Coccodiella on members of Melastomataceae from Ecuador and Panama. Phylogenetic analyses allowed us to confirm the placement of Coccodiella within Phyllachoraceae, as well as the monophyly of the genus. The phylogeny of representative species within the family Phyllachoraceae, including Coccodiella spp., graminicolous species of Phyllachora and taxa with erumpent to superficial stroma from several host families, suggests that the genus Phyllachora might be polyphyletic. Furthermore, tar spot fungi with superficial or erumpent perithecia seem to be restricted to the family Phyllachoraceae, independently of the host plant. We also discuss the biodiversity and host-plant patterns of species of Coccodiella worldwide.  相似文献   

14.
Deep-water trawl surveys on seamounts around New Caledonia yielded62 specimens of the little-known genus, Scaeurgus. Members ofthis genus of octopuses typically occur at depths of 200–500m in temperate and tropical latitudes worldwide. Prior to thisstudy, Scaeurgus was considered to contain one to two species.The new material from New Caledonia contained a surprising diversityof Scaeurgus species from a small area: three distinct new speciesare described and limited material of a further two taxa isreported. A pygmy member of this genus is reported for the firsttime. Distributions of these new taxa are consistent with reportsof high endemism on the seamount systems in this region. Fifty-eightof the 62 specimens were collected from seamounts, with fourof the five taxa unique to a single seamount. (Received 12 January 2004; accepted 28 January 2005)  相似文献   

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《Mycoscience》2020,61(5):212-218
Orientophila corticola is described as a new lichen-forming fungus from South Korea. The new species is distinguishable from other Orientophila species by the substrate preference to tree barks and the habitat specificity to inland areas. Molecular analyses applying internal transcribed spacer (ITS) and mitochondrial small subunit (mtSSU) sequences clearly classify O. corticola as a distinct species in the genus Orientophila. A surrogate key is provided to assist in the identification of all 13 taxa in the genus Orientophila.  相似文献   

17.
Fifteen taxa of the genus Cicer L. growing naturally in Turkey and out-groups were classified by phylogenetic and cladistic analysis. Taxa of the genus Cicer and the out-group taxa belonging to the closest genera Phaseolus L., Vicia L., Lathyrus L. and Ononis L., which are placed in Phaseoleae, Vicieae and Ononideae tribes, respectively, were used in molecular studies in order to derive their phylogenetic relationships. Morphological, palynological and seed characters were used on the basis of 143 traits. The micromorphological characters of seed and pollen grains were revealed by SEM. Lathyrus L. and Vicia L. species were used as out-groups for numerical analysis. Ten specimens were used for the measurements of metric characters related to the morphological structures of the taxa used for statistical analysis via PAUP and NTSYS-pc packages. Phylogenetic relationships between species and populations of the same species growing in different locations and their variations were determined using molecular methods performed on regions of the Inter Simple Sequence Repeat (ISSR). DNA was isolated from the collected samples, using modified CTAB protocols. ISSR was used for phylogenetic fingerprinting. The data were analyzed with NTSYS-pc package. Standardized data were used to generate a dendrogram that revealed the phylogenetic relationships of the taxa. Geographic distribution of the Cicer taxa appears to be closely related to the Anatolian Diagonal. As a result of this study, four new endemic taxa were added and evaluated for the first time.  相似文献   

18.
We use mitochondrial and nuclear sequence data to show that three weakly electric mormyrid fish specimens collected at three widely separated localities in Gabon, Africa over a 13-year period represent an unrecognized lineage within the subfamily Mormyrinae and determine its phylogenetic position with respect to other taxa. We describe these three specimens as a new genus containing two new species. Cryptomyrus, new genus, is readily distinguished from all other mormyrid genera by a combination of features of squamation, morphometrics, and dental attributes. Cryptomyrus ogoouensis, new species, is differentiated from its single congener, Cryptomyrus ona, new species, by the possession of an anal-fin origin located well in advance of the dorsal fin, a narrow caudal peduncle and caudal-fin lobes nearly as long as the peduncle. In Cryptomyrus ona, the anal-fin origin is located only slightly in advance of the dorsal fin, the caudal peduncle is deep and the caudal-fin lobes considerably shorter than the peduncle. Continued discovery of new taxa within the “Lower Guinea Clade” of Mormyridae highlights the incompleteness of our knowledge of fish diversity in West-Central Africa. We present a revised key to the mormyrid genera of Lower Guinea.  相似文献   

19.
《Journal of Asia》2019,22(1):63-66
Prionus sontinh new species, from Lai Chau, Lao Cai and Yen Bai provinces in northern Vietnam, is described and illustrated. The new species is compared with its closest taxa in the genus Prionus.urn:lsid:zoobank.org:act:8562579E-BD9F-4987-B7E2-E0D86E559713.  相似文献   

20.
Of the genera within the coralline algal subfamily Melobesioideae, the genera Leptophytum Adey and Phymatolithon Foslie have probably been the most contentious in recent years. In recent publications, the name Leptophytum was used in quotation marks because South African taxa ascribed to this genus had not been formally transferred to another genus or reduced to synonymy. The status and generic disposition of those species (L. acervatum, L. ferox, L. foveatum) have remained unresolved ever since Düwel and Wegeberg (1996) determined from a study of relevant types and other specimens that Leptophytum Adey was a heterotypic synonym of Phymatolithon Foslie. Based on our study of numerous recently collected specimens and of published data on the relevant types, we have concluded that each of the above species previously ascribed to Leptophytum represents a distinct species of Phymatolithon, and that four species (incl. P. repandum) of Phymatolithon are currently known to occur in South Africa.Here we present detailed illustrated accounts of each of the four species, including: new data on male and female/carposporangial conceptacles; ecological and morphological/anatomical comparisons; and a review of the information on the various features used previously to separate Leptophytum and Phymatolithon. Southern African species ascribed to the genus Phymatolithon may be separated from one another in the field by their growth forms, the substrata on which they are generally found, and the colour of living thalli. A key for identifying southern African specimens in the field is included. Our data support the conclusion that the characters upon which Leptophytum is based are unreliable for generic delimitation from Phymatolithon.  相似文献   

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