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1.
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   

2.
The genus Litsea in America is a small group of species with high variability that has not been evaluated rigorously; authors recognize either three or as many as 11 species because of the unclear delimitation of taxa. Our focus in this study was to resolve the number, names, and distinguishing features of the American species of Litsea, based on strict morphological analyses, namely Population aggregation analysis and Multivariate analyses. Population aggregation analysis revealed a large number of polymorphisms in all populations; nevertheless, L. aestivalis was distinguished from the other species. Ordination of character variability by principal components analysis and non-metric multidimensional scaling supported the distinction of seven additional species. Finally, eight species of Litsea are recognized in America and a key for their identification is provided.  相似文献   

3.
The HGL-50 locality, situated on the Glib Zegdou outlier in the Gour Lazib of Algeria (Hammada du Dra), is famous for having yielded several dental remains of primates dating from the late Early to the early Middle Eocene. These primates include Algeripithecus minutus, Azibius trerki and a new species of cf. Azibius (not described yet). Algeripithecus was widely acknowledged to be one of the oldest known anthropoids from Africa. However, very recent discoveries strongly suggest that Algeripithecus is closely related to Azibius and that both taxa are phylogenetically remote from the clade Anthropoidea. Algeripithecus and Azibius make up the family Azibiidae and appear as stem strepsirhines. Here we describe and analyse two ankle bones (tali) found in HGL-50. UM/HGL50-466 is a small left talus, which is appropriate in size to belong to A. trerki, while UM/HGL50-467 is a right talus, which is significantly larger and appropriate in size to belong to the new large species of cf. Azibius. Both tali exhibit a suite of features that resemble conditions primarily found in extinct and extant strepsirhine and adapiform primates; conditions that are consistent with the strepsirhine-like dentition characterizing azibiids. Functionally, these two tali indicate that Azibius species were engaged in a form of active arboreal quadrupedalism with some ability to climb and leap. Azibiids were rather small-bodied primates, approximating the size of some modern dwarf lemurs (Cheirogaleidae) and sportive lemurs (Lepilemuridae) from Madagascar. Given their small body-size and their talar morphology, living cheirogaleid lemurs, which are agile arboreal quadrupeds (with climbing, springing and branch running activities), might appear as good analogues for azibiids in terms of locomotor behaviour.  相似文献   

4.
Diverse collections of Cortinarius pseudofallax from several European countries were studied using morphological characters and ITS1-5.8S-ITS2 genes from sequence data. They were compared with some close species such as C. cedriolens, C. neofallax and C. parvannulatus. All these taxa share some features like a light brown pileus, a stipe provided with a more or less developed whitish veil, small and well-ornamented spores and, above all, a typical strong and perfumed acidulous smell; in addition. the phylogenetic tree built with the ITS gene sequences of these vouchers showed that they clustered in a well-supported clade, here treated as section Parvuli. Our specimens of C. pseudofallax are morphologically described and illustrated with pictures of fresh specimens and basidiospores seen under SEM. A discussion of their taxonomic relationships with another group of similar species belonging to the C. decipiens sensu lato complex is presented.  相似文献   

5.
This paper critically reviews the status of the ??lotus vines?? (Lotus section Rhyncholotus) in the wild and in cultivation. The literature concerning the conservation status of this group is scattered and in many places is not updated. Besides, the most recent efforts in conservation on this group have not been published in widely available sources and are mainly published in Spanish. Our aims in this paper are to compile the most recent information regarding the conservation status, studies on genetic diversity and the latest strategies for the conservation of this group. The four species are all critically endangered in the wild. Two species (Lotus berthelotii and L. maculatus) are widely cultivated in Europe and North America but the range of genotypes in cultivation is likely to be small, as the plants are propagated by cuttings. Hybrids between these two species are also in cultivation, and some have been patented. Commercial horticulture has considerable implications for overall conservation strategies, and these implications are discussed. We suggest that a circa situm conservation could improve the conservation strategies of these four species in the Canary Islands.  相似文献   

6.
Heterodera fici is redescribed and illustrated with comparative details and revised measurements and diagnostic characters of the females, males, cysts, and juveniles from Maryland and Pakistan. This species is in the "schachtii group" (cysts lemon shaped, with bullae, and ambifenestrate) but the fenestrae in some cysts, presumab!y young ones, are small and widely spaced, appearing bifenestrate. It is most closely related to H. schachtii, H. glycines, and H. cajani but differs from these species especially in having cysts with small, scattered bullae and weakly developed underbridge; and males with four small nipples on tail tip. Scanning electron microscopy (SEM) observations of the specimens are also presented. The relationship of this species to closely related forms is discussed.  相似文献   

7.
8.
A new hemiurid digenean, Saturnius gibsoni n. sp., is described from the stomach lining of Mugil cephalus L. off Oran, Mediterranean coast of Algeria. Characteristic morphological features of the new species include small size of the body which is comprised of six pseudosegments, small ventral sucker, weakly developed mound-shaped flange at the level of the ventral sucker, and eggs being large in relation to the size of the body. Saturnius gibsoni n. sp. resembles S. minutus Blasco-Costa, Pankov, Gibson, Balbuena, Raga, Sarabeev & Kostadinova, 2006 and two unidentified Saturnius spp. in the small size of the body and most metrical features. However, in spite of the presence of five transverse septa resulting in six pseudosegments and the range overlap of some metrical features, the ventral sucker in S. minutus is much larger, the ventral sucker muscular flange is more prominent, the last pseudosegment is narrower in relation to body width and more rounded, and the eggs are smaller (mean 21 × 10 vs 25 × 12 μm). Furthermore, the partial sequences of the 28S rRNA gene region (domains D1–D3; 1,195 nt) obtained from two isolates of S. gibsoni n. sp. differed by 11 nt (0.9%) from that of S. minutus. Both unidentified forms of Saturnius are clearly distinguishable from S. gibsoni n. sp. by the presence of six stout, transverse muscular septa, forming seven pseudosegments (vs five septa forming six pseudosegments). Bayesian inference analysis of partial 28S rDNA sequences based on a total of 15 species from the families Hemiuridae and Lecithasteridae depicted the Bunocotylinae Dollfus, 1950 as a strongly supported basal clade, with Bunocotyle progenetica (Markowski, 1936) as the closest sister taxon to Saturnius spp.  相似文献   

9.
10.
Cucullanus brevicaudatus n. sp. (Cucullanidae) is described from the intestine of Balistes capriscus Gmelin (Balistidae) off Rio de Janeiro, Brazil. The new species can be differentiated from its congeners in the small body length, the shape of the gubernaculum, the particular size and morphology of the tail in both males and females, the arrangement of the caudal papillae, the narrow oesophageal base, and the eggs with rugged shells. In addition, the combination of some features, i.e. number of caudal papillae, spicule length, oesophagus/body length ratio, host family and geographical distribution, can help to easily distinguish the new species from other cucullanids. Considering these features, C. brevicaudatus differs from the species assigned to Dichelyne Törnquist, 1931 which exhibit morphological proximity with Cucullanus Müller, 1777. Regarding the life-cycle of cucullanid nematodes, available evidence suggests that some species are primarily heteroxenous using invertebrates (i.e. crustaceans, polychaetes) as intermediate hosts, but in other a histotrophic phase in the definitive host replaces the intermediate host.  相似文献   

11.
The giant bathymodioline mussels from vents have been studied as models to understand the adaptation of organisms to deep-sea chemosynthetic environments. These mussels are closely related to minute mussels associated to organic remains decaying on the deep-sea floor. Whereas biological data accumulate for the giant mussels, the small mussels remain poorly studied. Despite this lack of data for species living on organic remains it has been hypothesized that during evolution, contrary to their relatives from vents or seeps, they did not acquire highly specialized biological features. We aim at testing this hypothesis by providing new biological data for species associated with organic falls. Within Bathymodiolinae a close phylogenetic relationship was revealed between the Bathymodiolus sensu stricto lineage (i.e. “thermophilus” lineage) which includes exclusively vent and seep species, and a diversified lineage of small mussels, attributed to the genus Idas, that includes mostly species from organic falls. We selected Idas iwaotakii (Habe, 1958) from this latter lineage to analyse population structure and to document biological features. Mitochondrial and nuclear markers reveal a north-south genetic structure at an oceanic scale in the Western Pacific but no structure was revealed at a regional scale or as correlated with the kind of substrate or depth. The morphology of larval shells suggests substantial dispersal abilities. Nutritional features were assessed by examining bacterial diversity coupled by a microscopic analysis of the digestive tract. Molecular data demonstrated the presence of sulphur-oxidizing bacteria resembling those identified in other Bathymodiolinae. In contrast with most Bathymodiolus s.s. species the digestive tract of I. iwaotakii is not reduced. Combining data from literature with the present data shows that most of the important biological features are shared between Bathymodiolus s.s. species and its sister-lineage. However Bathymodiolus s.s. species are ecologically more restricted and also display a lower species richness than Idas species.  相似文献   

12.
Gerald Mayr 《Geobios》2006,39(6):865
A postcranial skeleton of a small bird from the early Oligocene locality Pichovet in Southern France is described and identified as Eocuculus cf. cherpinae Chandler, 1999. It is the second fossil record of Eocuculus which was hitherto known from a postcranial skeleton from the late Eocene of North America only. Although Eocuculus shares some derived similarities with Cuculidae (cuckoos), it distinctly differs in a number of osteological features from crown group members of this taxon. If future, more complete skeletons prove its cuculiform affinities, Eocuculus is a stem lineage representative of this taxon and not within the crown group. Recognition of Eocuculus in the early Oligocene of France provides evidence for the presence of an extinct late Eocene/early Oligocene avian taxon with an intercontinental Northern Hemisphere distribution.  相似文献   

13.
A relict endemic species originating from Turkey, Thermopsis turcica, was excluded from Thermopsis in consideration of morphologic studies based on its flowers and fruits as well as micromorphological features that were obtained by scanning electron microscopy (SEM) and data from supporting molecular analyses internal transcribed spacer (ITS). Additionally, phylogenetic analyses (maximum parsimony and neighbour-joining) were conducted using PAUP 4.0 software. These analyses supported a new taxonomical position for the Turkish species. SEM and morphological studies indicated that the species has unique features that have not been observed in other Thermopsideae species. The unique features and characteristics are comprehensively illustrated here. For confirmation of our purpose, the chromosome number and karyotype of V. turcica were determined via the KAMERAM software program. As a result, all detailed examinations and comparisons of Vuralia and related genera suggest that Vuralia is a new monotypic genus within Thermopsideae, and a new genus and combination nova were established for this Turkish species.  相似文献   

14.
Pavel Javornicky 《Hydrobiologia》2003,502(1-3):271-283
The cryptomonads sampled frequently from pelagial of large freshwater bodies, lakes and ponds, but also found in littoral regions and in small water bodies covered with vegetation, are often characterized by the sigmoid (S-shaped) form of their cells. According to the quoted findings of electron microscopy it seems that these species should be incorporated into the new genus Campylomonas Hill. Because the EM characteristics have not been proved so far for all species, and the following nomenclatural combinations accomplished, the traditional classification into the genus Cryptomonas is kept here. The correct name for the largest of sigmoid cryptomonads is Cryptomonas curvataEhr. em. Penard. Contrarily, C. rostrata Troitz. em. Kisel. is to be held for later synonyms. The existence of the species C. rostratiformis Skuja remains uncertain. The smaller species of sigmoid shape, i.e. C. reflexa (Marss.) Skuja and C. marssonii Skuja, may also easily be discerned under the light microscope. From the small puddles with H2S in water, shortened forms of both these species are documented, one of them under the published name C. anas Javorn. The pelagic assemblage of the above sigmoid cryptomonads frequently is completed by Plagioselmis nannoplanctica (Skuja) Novar., Lucas et Morr. and by P. lacustris (Pasch. et Ruttn.) Javorn. These flagellates so far are currently determined as the species of the genus RhodomonasKarsten. In addition to the EM characteristic, they differ from Rhodomonas by the absence of a true gullet (pseudopharynx) having only the ventral furrow with rows of superficial ejectosomes (similar to the genus Cryptochrysis Pascher). The ellipsoidal or ovoid cryptomonads are sampled more frequently from peat pools and small water bodies covered with vegetation than from open pelagial of lakes. An erroneous determination of them causes confusion. Because some strains are wrongly labeled, electron-microscopic characteristics are vaguely determined species. For example, some EM features of Cryptomonas ovata in fact belong to C. pyrenoidifera Geitl. or to C. phaseolus Skuja. Cryptomonas ovata Ehr. em. Stein is not a collective species with a wide dimensional range of ellipsoid cells. It is a large species the typical morphology which is described here in detail. C. splendida Czosn. differs from C. ovata only by the transversal orientation of the cell. Similar to C. ovata but smaller species is C. tatrica Czosn. These species are further compared with the well-defined species C. obovata Skuja and the particularly small C. phaseolus Skuja.  相似文献   

15.
Three new species of Hatschekia Poche, 1902 are described from the gill filaments of three species of boxfishes captured off southern Japan: H. pseudostracii n. sp. on Kentrocapros aculeatus (Houttuyn) (Aracanidae); H. bibullae n. sp. on Lactoria diaphana (Bloch & Schneider) (Ostraciidae); and H. kuroshioensis n. sp. on Tetrosomus concatenates (Bloch) (Ostraciidae). Of the 93 currently valid species in the genus, these new species differ from the 87 species which lack four stout processes on the posterior margin of the intercoxal sclerites of legs 1 and 2. Those processes are present on the remaining six species and the three new species. Of these nine species, H. pseudostracii n. sp. is distinguished by having a T-shaped chitinous frame on the cephalothorax, the leg 1 exopod twice as long as the endopod and a small parabasal papilla. H. bibullae n. sp. can be differentiated by a combination of morphological features as follows: a well-developed, thumb-shaped parabasal papilla, the leg 1 exopod twice as long as the endopod and a trunk lacking posterior lobes. H. kuroshioensis n. sp. can be recognised by bearing a T-shaped chitinous frame on the cephalothorax, the leg 1 exopod is three times as long as the endopod and the trunk lacks posterior lobes.  相似文献   

16.
An esterase duplication is described in the sibling species pair Drosophila mojavensis and Drosophila arizonensis. We present evidence for two separate structural loci mapping at a distance of less than 0.16 recombination units from each other. Alleles at the two loci have the same substrate specificities and form small amounts of interlocus heterodimers. One locus (Est-5) is functioning throughout the insect's life cycle and appears at high concentrations in the hemolymph and the fat body. Its duplicate (Est-4) functions only during the late larval stage and is concentrated mainly in the carcass. No null alleles at either locus were observed in population surveys. An examination of 12 other species from the repleta group, to which D. mojavensis and D. arizonesis belong, suggests that Est-5 is universally present, but the activity levels of Est-4 vary among species and may be totally absent in some species. Variation in the level of Est-4 activity does not closely follow the phylogenetic relationship.  相似文献   

17.
《Journal of Asia》2022,25(4):101989
DNA barcodes obtained from cytochrome c oxidase subunit 1 (cox1) offer a fast and easy way to identify a range of biological organisms. Culicoides (Diptera: Ceratopogonidae) are a group of small, blood sucking midges whose species are the vectors for some arboviruses, such as bluetongue virus, African horse sickness virus, epizootic hemorrhagic disease virus and equine encephalosis virus. Identification of these small insects is difficult so constructing DNA barcode libraries for species present in certain areas is helpful to clarify the taxonomy and assist non-specialist workers to identify species. In this study, we analysed specimens belonging to C. subgenus Hoffmania collected from 12 towns of Yunnan Province, China. Specimens were identified by morphology and processed to construct DNA barcodes. A total of 185 specimens referable to 6 morphological species were processed for cox1 and 28S rRNA sequencing. The resulting 185 cox1 sequences were assigned to 13 barcode index numbers (BINs) which include 9 novel BINs. Molecular and morphological evidence was used to support the transfer of 4 species previously assigned to C. subg. Avaritia into C. subg. Hoffmania. Molecular analysis revealed the presence of 7 potential cryptic species within C. innoxius, three within C. liui and two within C. insignipennis.  相似文献   

18.
Arthropods do not have one, but two genes encoding an allatostatin C-like peptide. The newly discovered paralog gene was called Ast-CC, and the peptide which it is predicted to make was called allatostatin double C (ASTCC). Genes for both allatostatin C (ASTC) and its paralog were found in the tick Ixodes scapularis as well as dipteran, lepidopteran, coleopteran, aphidoidean and phthirapteran insect species. In addition partial or complete cDNAs derived from Ast-CCs were found in a number of species, including Drosophila melanogaster, Bombyx mori and Rhodnius prolixus. The ASTCC precursors have a second conserved peptide sequence suggesting that they may produce two biologically active peptides. The predicted precursors encoded by the Ast-CCs have some unusual features, particularly in Drosophila, where they lack a signal peptide, and have instead a peptide anchor. These unusual structural features suggest that they are perhaps expressed by cells that are not specialized in neuropeptide synthesis and that in Drosophila ASTCC may be a juxtacrine. Data from the Fly Atlas project show that in Drosophila Ast-CC is little expressed. Nevertheless a P-element insertion in this gene is embryonic lethal, suggesting that it is an essential gene. Similarity between the precursors and receptors of ASTC/ASTCC and somatostatin suggests that ASTC/ASTCC and somatostatin have a common ancestor.  相似文献   

19.
The karyotype of Mustela kathiah was first described. Its structure is most similar to the karyotype of M. altaica, differing in the morphological peculiarities of five pairs of large chromosomes. A comparative analysis of mitochondrial genes in the species Mustela allowed us to clarify understanding of the place of M. kathiah in the system of the genus. The earlier hypothesized proximity of the species to a group of small weasels (altaica, nivalis) or to a group of South Asian species (strigidorsa, nudipes) was not confirmed. A high level of differences between M. kathiah of Vietnam and specimens from southern China in nucleotide sequences of the cytochrome b (7.7%) and ND2 (6–6.2%) genes was found. It is supposed that difference in the two gene sequences found in geographically distanced populations of M. kathiah may be adaptive.  相似文献   

20.
The distributional pattern of AT- and GC-rich regions and the physical mapping of ribosomal DNA (location of 18S-5.8S-26S and 5S rDNA) in the chromosomes of seven Artemisia species have been established by means of fluorochrome banding and fluorescence in situ hybridization (FISH). This is the first study in the large genus Artemisia using FISH. Five species (A. barrelieri, A. caerulescens subsp. gallica, A. fragrans, A. herba-alba subsp. valentina, A. herba-alba subsp. herba-alba) belong to the subgenus Seriphidium, one of the most homogeneous in the genus; one (A. tridentata susbp. spiciformis) belongs to the small subgenus Tridentatae, classically included in Seriphidium; and one (A. annua) belongs to the subgenus Artemisia, but shows some affinities with Seriphidium. Genome organization is relatively constant in all the species studied. AT- and GC-rich DNA is predominantly terminal, but some intercalary and centromeric bands also exist. The rDNA loci are also most often terminal and usually located in GC-rich regions. 5S rDNA sites are present in a lower number than 18S-5.8S-26S sites, and are always colocated with some of them. In the light of these cytogenetic features, subgenus Seriphidium is clearly placed within the genus Artemisia, so that it does not make sense to segregate it as a genus; on the other hand, subgenus Tridentatae must not be classified within Seriphidium, but kept as an independent subgenus.  相似文献   

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