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1.
A new species of the apicomplexan genus LeucocytozoonBerestneff, 1904, L. artamidis n. sp., is described from the Australian avian family Artamidae. Gametocytes and endogenous stages of the life-cycle are described together with early erythrocytic and leucocytic developing forms rarely described for species of this genus.  相似文献   

2.
This study examines the contribution of early‐stages and adult characters to the reconstruction of the phylogeny of Brassolini butterflies. Parsimony analyses used both equal weights and implied weights, and a series of analyses were performed. First, we analysed adult and early‐stages partitions independently and in combination for a subset of 27 species; in these cases the matrices were mostly complete. Whereas the adult partition alone produced a topology that was well resolved and congruent with previous studies, the early‐stages partition produced a poorly resolved tree under equal weights. Furthermore, implied weights produced a well‐resolved early‐stages topology that differed significantly from the adult topology. When both partitions were combined for 27 species, implied weights yielded a topology that resembled the adult tree except for the positions of Bia and Penetes, but statistical node support was generally lower. This suggests that stochastic noise increased when early‐stage characters were added to the adult partition, but the combined partitions topology was not statistically different from that based on adult characters alone. Second, given that preserved early stages are not as readily available as adults, we analysed a matrix including 45 species in which early‐stage data were missing for 18 species, and compared the topology to that produced by the adult partition alone. Results were similar to the analyses including fewer species; the combined partitions tree was similar to that from the adult partition except for the position of Bia and Penetes. We compare our findings to other genus‐level phylogenetic studies within Lepidoptera that have also used early‐stages and adult characters.  相似文献   

3.
Three newly discovered larval specimens of the genus Muraenolepis collected from the waters of the western Antarctic Peninsula are described. Knowledge of their natural history is sparse and information about their early life history is based on only a few larval stages. Here, the available literature on larval eel cods is reviewed, and the specimens placed in context.  相似文献   

4.
【目的】通过检测郫县豆瓣在不同发酵阶段细菌的种类、丰度及数量,探究郫县豆瓣的不同发酵产品发酵过程中细菌的动态变化情况。【方法】采用16S rRNA基因测序对郫县豆瓣4个发酵阶段中细菌种类及丰度进行分析,利用荧光定量PCR(quantitative real-time PCR,qPCR)方法检测不同发酵阶段的细菌总数。【结果】郫县豆瓣在初期的发酵过程中细菌群落处于动态稳定,在不同发酵阶段细菌群落组成相对丰富,从郫县豆瓣整个初期的发酵过程来看,细菌群落多样性呈现升高的趋势,Shannon指数从1.25升高到3.50;在郫县豆瓣初期发酵过程中细菌群落的数量以及多样性与发酵环境息息相关,不同发酵阶段细菌群落的多样性也有所不同,其中在干辣椒发酵阶段中泛菌属(Pantoea)为最优势菌属,占比为20%;在蚕豆瓣发酵阶段中葡萄球菌属(Staphylococcus)的相对丰度最高,占比为38%;混合发酵后,在红油豆瓣发酵阶段的最优势菌属是乳酸杆菌属(Lactobacillus),占比达到27%,郫县豆瓣发酵阶段的最优势菌属是乳酸杆菌属(Lactobacillus),占比为62%。【结论】推断在郫县豆瓣不同发酵阶段初期相对丰度较大的菌属对郫县豆瓣的质量以及产量可能会产生重大影响。  相似文献   

5.
The morphology of the juvenile stages of the oribatid mite, Liacarus (Dorycranosus) acutus, is described. The juvenile stages of four species of the genus Liacarus are compared.  相似文献   

6.
Abstract

Atalophlebioides Phillips is redescribed as a monotypic genus endemic to New Zealand. All life stages of A. cromwelli (Phillips) are described, and a lectotype is designated. The relationships of the genus and the ecology of A. cromwelli are discussed.  相似文献   

7.
Seven specimens of Rhynchodemus sylvaticus (Leidy) collected from a variety of localities in the US and having variously developed copulatory organs are believed to represent stages in the development of the copulatory apparatus. Four specimens were juveniles with under-developed male components, one specimen had a well-developed female atrium and small male component, and two specimens were mature with a male organ twice the size of the female part. In early stages, the male component had sperm ducts, seminal vesicle, and narrow atrium; more mature stages had a considerable elongated atrium with thick folds in its muscularized wall, a massive muscular bulbus; and a sigmoid ejaculatory duct opening into the large bulbar cavity. Morphological features of mature male copulatory organs in all species of the genus Rhynchodemus are basically similar whereas external body features (color and number of dorsal stripes) of these same species differ.  相似文献   

8.
Abstract

The endemic New Zealand genus Eulimnia and its two species are redescribed. Data are presented on the life cycle of E. philpotti Tonnoir & Malloch, and the habitat, geographical distribution, phenology, and biological features of adults and immature stages are discussed. Adults are found in permanently wet marshes, where the larvae prey on fingernail clams (Bivalvia: Sphaeriidae) while completely submerged. Mature larvae form puparia among vegetation or debris above the water level. The immature stages of E. philpotti are described. The genus is placed in tribe Tetanocerini, and its taxonomic position is discussed.  相似文献   

9.
10.

The biology of immature stages of the Diptera that accompany xylophagous insects inhabiting sap runs and tree holes was studied. Biological data are reported for the first time for 4 species and supplemented for 2 more species of the genus Phaonia Robineau-Desvoidy, 1830 (Muscidae). The main diagnostic characters of these species are given. The species differ in the life history of larvae, the morphology of the anterior and posterior spiracles, creeping welts, cephalopharyngeal apparatus, and anal plate. A key to immature stages of xylobiont species of the genus Phaonia is compiled.

  相似文献   

11.
Abstract

A new species of the lacazelline brachiopod genus Ospreyella is described from shallow cryptic habitats in Palau, western Caroline Islands and Arnd Atoll, Pohnpei, eastern Caroline Islands, north‐western Pacific Ocean. This new taxon, here named Ospreyella palauensis, and representing the third discovery of a species of Ospreyella from the Indo‐Pacific region, is compared with the other two recently described extant species of the genus, O. depressa Lüter from the Great Barrier Reef, Australia, and O. maldiviana Logan from the Maldive Islands, northern Indian Ocean. An ontogenetic sequence is described for the new species and compared with those previously described for other Holocene lacazellines. Additionally, a study of ontogenetic stages in Thecidellina congregata from Saipan in the Northern Mariana Islands shows early‐stage similarities to those of the new species and other lacazellines. These observations on development in extant forms provide important analogies for comparison with ontogenetic stages in ancestral fossil forms and information which may be useful in reconstructing thecideide phylogenetic history.  相似文献   

12.
A new mobergellan genus and species,Tateltella ranoculata, is described from the early Middle Cambrian (Agdzian Stage) of Morocco. The new taxon is characterized by only four pairs of muscle scars and is furthermore distinguished from other mobergellans by its strongly concave shape and its distally rising muscle scars. The individual specimens ofTateltella ranoculata distinctly vary in size and display different ontogenetic stages. Juvenile, intermediate, and adult stages can be distinguished by means of the development of the muscle scars that differ in Position relative to the apex, size, and distinctness between individual stages. The shell ofT. ranoculata is composed of a succession of thin phosphatic lamellae separated by interlamellar gaps, presumably originally filled by organic material. The interlamellar gaps may be divided by septum-like structures producing discrete cavities. The specimens are the youngest mobergellans known so far and correlation of their stratigraphic position suggests a correspondence with the lower part of the Amgan stage of the Siberian Platform. In addition, they are the first reported mobergellans from the present day continent Africa. Other mobergellan taxa and mobergellan-like species are briefly reviewed and the genusHippoklosma Missarzhevsky, previously assigned to the Mobergellidae, is excluded from the family due to its different shell structure. An evolutionary trend of reduction in the number of muscle scars from 14 in the early Early Cambrian to only eight in the early Middle Cambrian is apparent among mobergellans.   相似文献   

13.
O.A. Sæther 《水生昆虫》2013,35(3):177-196
Diagnoses of all stages of the new genus Aagaardia are given. The genus includes A. sivertseni (Aagaard), originally described in Eukiefferiella Thienemann, from Norway and Finland and described in all stages; A. protensa sp.n. from Finland and A. triangulata sp.n. from Turkey described as male imagines; and A. longicalcis sp.n. from Canada described in both sexes. The male imagines share bare eyes, strong punctation on wings, bare squama, extended costa, triangular gonostylus and two groups of extremely strong and sclerotized virga. The pupa and the female genitalia show relationship with Paratrissocladius Zav[rcirc]el, while the larva is very similar to the larvae of Psilometriocnemus Sæther and Platysmittia Sæther. Parsimony analyses suggest that Aagaardia forms the plesiomorphic sister genus to the rest of the Heterotrissocladius group combined.  相似文献   

14.
The genus Paegniodes Eaton, 1881 and its type species P. cupulatus (Eaton, 1871) have never been described in detail completely. In this article, all stages are described and photographed. Compared to other heptageniid genera, the adults of P. cupulatus have a more colourful body, smaller hindwings but larger titillators. The nymphs of this species have no setae or tubercles on the body and no emarginations on the head capsule. They have smaller lamellae of the first gills, a wider labrum with a median notch, mandibles without setae on outer margins, maxillae with a row of setae and scattered setae on the ventral surface, cerci with mesal setae, and a median filament with setae on both sides. Both imaginal and nymphal stages of the genus have unique characters, so the taxon Paegniodes is recognized at the rank of genus here. It appears closely related to Rhithrogena Eaton, 1881.  相似文献   

15.
16.
Morphological studies were undertaken on Gastroclonium pacificum (E.Y. Dawson) C.F. Chang et B.M. Xia (Champiaceae, Rhodymeniales) from Japan. We describe the details of male reproductive structures, the procarp and early post‐fertilization stages. This species has a solid axis, with both tetrasporangia and polysporangia, spermatangia are cut off from spermatangial parent cells, and a procarp is composed of a 4‐celled carpogonial branch and two 2‐celled auxiliary cell branches. The mature cystocarp lacks a conspicuous ostiole, a characteristic of the genus Gastroclonium. The most distinctive characteristic of the species is the tela arachnoidea, which is lacking in other species of Gastroclonium.  相似文献   

17.
18.
The taxonomic validity of the genus Hydropuntia Montagne (1843) (including Polycavernosa) within the Gracilariaceae (Gracilariales, Rhodophyta) is controversial. Morphological characters that define species of Hydropuntia are said to be variable and to overlap with those of Gracilaria. Here we present a global phylogenetic study of the family based on a Bayesian analysis of a large rbcL DNA sequence dataset indicating that the genus Hydropuntia forms a well supported monophyletic clade within the family, and recognize Hydropuntia as a genus distinct from Gracilaria. We also conducted smaller phylogenetic analyses in which thirty four Hydropuntia rbcL sequences resulted in two major clades within the genus, comprising a Caribbean clade and an Indo‐Pacific clade. Diagnostic reproductive stages that separate these two clades will be illustrated.  相似文献   

19.
Revised and emended generic diagnoses for all stages and both sexes of Paracricotopus Thienemann and Harnisch are given. The genus appears most closely related to Rheocricotopus Thienemann and Harnisch with some similarities of larvae and females to Nanocladius Kieff. and Mesocricotopus Brund. All stages and both sexes are described or redescribed of the Palaearctic Paracricotopus niger (Kieffer) and of Paracricotopus glaber n. sp. from South Carolina.  相似文献   

20.
Reconstructing evolutionary history for emerging species complexes is notoriously difficult, with newly isolated taxa often morphologically cryptic and the signature of reproductive isolation often restricted to a few genes. Evidence from multiple loci and genomes is highly desirable, but multiple inputs require ‘common currency’ translation. Here we deploy a Shannon information framework, converting into diversity analogue, which provides a common currency analysis for maternally inherited haploid and bi‐parentally inherited diploid nuclear markers, and then extend that analysis to construction of minimum‐spanning networks for both genomes. The new approach is illustrated with a quartet of cryptic congeners from the sexually deceptive Australian orchid genus Chiloglottis, still in the early stages of speciation. Divergence is more rapid for haploid plastids than for nuclear markers, consistent with the effective population size differential (Nep < Nen), but divergence patterns are broadly correlated for the two genomes. There are nevertheless intriguing discrepancies between the emerging plastid and nuclear signals of early phylogenetic radiation of these taxa, and neither pattern is entirely consistent with the available information on the sexual cues used by the orchids to lure the pollinators enforcing reproductive isolation. We describe possible extensions of this methodology to multiple ploidy levels and other types of markers, which should increase the range of application to any taxonomic assemblage in the very early stages of reproductive isolation and speciation.  相似文献   

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