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1.
We have used newly discerned morphological characters as well as molecular‐sequence data from 18S and 28S rDNA to revise the families recently designated as the ‘9+0’ acoels – what we call Convolutida. Characters from the ultrastructure of sperm, with their ‘9+0’ axonemes, are useful in delineating the Convolutida, but are either species‐specific or too conserved within the group to be used to infer relationships within it. Male genital organs, prostatoid organs, and sagittocysts, on the other hand, give a good phylogenetic signal for reconstructing relationships of such genera as Conaperta, Anaperus, and Achoerus; some features of the reproductive organs correlate with habitat and show how the Convolutida probably originated as epiphytic predators and radiated into the mesopsammon, pelagic, and coral‐associated realms. In this revision of the Convolutida we provide revised synopses of its families – which we restrict to the Anaperidae, Convolutidae, and Sagittiferidae – and describe a new species, Polychoerus gordoni, from New Zealand. We transfer the genus Adenopea from the Antroposthiidae to the Convolutidae; Conaperta, Neochildia, and Oxyposthia from the Convolutidae to the Anaperidae; Paranaperus and Praeanaperus from the Anaperidae to the Haploposthiidae. Convoluta aegyptica is synonymized with Convoluta boehmigi, Convoluta lacazii with Convoluta sordida, and the genus Picola (Convolutidae) with Deuterogonaria (Haploposthiidae). Amphiscolops blumi, A. carvalhoi, and A. langerhansi, all of which possess a cellular seminal bursa, are transferred to the genus Heterochaerus. Convoluta elegans and Pseudanaperus tinctus are classified as nomina nuda. We use our findings on the ultrastructure of female genital organs and spermatozoa to show that sexual conflict plays a major role in the evolution of diversity of these structures and that the phylogeny of the Acoela would comprise early forms without female genital organs and hyper‐ or hypodermal transfer of sperm through advanced forms with ever longer and narrower bursal nozzles and sperm with axial microtubules. Moreover, our results show that the acquisition of endosymbiotic algae happened at least twice within the Acoela.  相似文献   

2.
Morphological features of the Acoela appear to be quite plastic, including those of the copulatory organs, which provide the principle characteristics used for the systematics of this group. Consequently, classification schemes of the Acoela comprise numerous polyphyletic groupings. In this review, we detail recent revisions of acoel systematics using molecular sequence data and new and reevaluated morphological characteristics. Gene trees are discordant with traditional systematic schemes but strongly concordant with new morphological characteristics obtained through the use of transmission electron microscopy and confocal laser scanning microscopy, namely, characteristics of body-wall and copulatory organ musculature, sperm, sperm ducts, sagittocysts, and immunocytochemistry of the nervous system. This merger of molecular and morphological data has led to significant changes in acoel classification, including a major emendation of the largest family of the Acoela, the Convolutidae, whereby half of its members were transferred to a newly created family, the Isodiametridae.  相似文献   

3.
In an effort to understand the phylogeny of the Platyhelminthes, the patterns of body-wall musculature of flatworms were studied using fluorescence microscopy and Alexa-488-labeled phalloidin. Species of the Catenulida have a simple orthogonal gridwork of longitudinal and circular muscles. Members of the Rhabditophora have the same gridwork of musculature, but also have diagonal muscles over their entire body. Although a few species of Acoelomorpha possessed a simple orthogonal grid of musculature, most species typically have distinctly different patterns of dorsal and ventral body-wall musculature that include sets of longitudinal, circular, U-shaped, and several kinds of diagonal muscles. Several distinct patterns of musculature were identified, including 8 patterns in 11 families of acoels. These patterns have proven to be useful in clarifying the phylogeny of the Acoelomorpha, particularly with regard to the higher acoels. Patterns of musculature as well as other morphological characters are used here for revisions of acoel systematics, including the return of Eumecynostomum sanguineum (Mecynostomidae) to the genus Aphanostoma (Convolutidae), the revision of the family Childiidae, and the formation of a new family, Actinoposthiidae.  相似文献   

4.
A new species of microsporidia from Drosophila melanogaster was investigated by light and electron microscopy and by ribosomal RNA (rRNA) sequencing. This microsporidium and the previously described Nosema kingi and Nosema acridophagus have been transferred to the new genus Tubulinosema gen. nov. with the following characters: nuclei are in diplokaryotic arrangement during the life cycle. All stages are in direct contact with the host cell cytoplasm, slightly anisofilar polar tube with the last coils being smaller in diameter arranged in one or two rows on both sides of the diplokaryon and small tubuli on the surface of late meronts. Spores are oval or slightly pyriform. Thick endospore wall, thinner over anchoring disc. This new genus and the genus Brachiola have been placed in a new family Tubulinosematidae fam. nov. Phylogenetic analysis of small subunit rRNA sequences by different methods placed Tubulinosema spp. in one clade with the genus Brachiola forming its sister clade, which is distant from the clade containing the true Nosema spp. including Nosema bombycis.  相似文献   

5.
The data on fossil platanoids and hamamelids are generalized, their morphological diversity and probable patterns of the establishment of the extant families Platanaceae and Hamamelidaceae are analyzed. It is shown that morphological and epidermal characters of polymorphic leaves of typical platanoid appearance were formed in the Late Albian and remained essentially invariable to the present time, indicating the morphological stasis of these leaves combined with a wide variation range. In view of association with essentially different reproductive structures, it is proposed to classify these leaves by the morphological system irrespective of the natural system of angiosperms. A new system of extinct platanoids and hamamelids, which is based on reproductive structures and includes two orders, Hamamelidales and Sarbaicarpales ordo. nov., is proposed. Hamamelidales comprises two extant families, Platanaceae (with the subfamilies Platanoideae subfam. nov. and Gynoplatananthoideae subfam. nov.) and Hamamelidaceae, and the extinct family Bogutchanthaceae fam. nov.; the new extinct order Sarbaicarpales ordo. nov. consists of two new families, Sarbaicarpaceae fam. nov. and Kasicarpaceae fam. nov. In a system of flowering plants that is based on molecular data, the families Platanaceae and Hamamelidaceae are assigned to remote orders, excluding close relationship (APG, 2003). At the same time, the system of APG II often contradicts morphological and paleontological data, while traditional ideas of morphologists concerning the common origin of these families have recently been supported by paleobotanic evidence. Probable origin of the families Platanaceae and Hamamelidaceae from a common polymorphic ancestral group is discussed.  相似文献   

6.
Abstract: A new family, Sinoalidae Wang and Szwedo fam. nov., is described from the Middle Jurassic Daohugou Biota (Inner Mongolia, China). Two new genera with three new species (Sinoala parallelivena Wang and Szwedo gen. et sp. nov., Jiania crebra Wang and Szwedo gen. et sp. nov., and Jiania gracila Wang and Szwedo sp. nov.) are erected based on well‐preserved whole‐bodied specimens. The morphological characters of Procercopidae and the new family are given, and a key to the species of Sinoalidae is presented. The genera Luanpingia Hong, 1983 and Huabeicercopis Hong, 1983 are revised and attributed to Sinoalidae. The genera Mesocercopis Hong, 1983 and Sinotettegarcta Hong, 1986 are considered junior synonyms of Anthoscytina Hong, 1983. Taxa assigned to Sinoalidae fam. nov. cannot be attributed to any previously known family, but share some general (plesiomorphic) characters with ancient Clypeata, for example, postclypeus distinctly swollen, transversely wrinkled, antenna with a flagellum of a few elongate segments, frons with median ocellus and lateral ocelli on crown. Moreover, the new family is closely related to Procercopidae (Cercopoidea) based on a pronotum with a median incision at the hind margin; tegmen slender, partly punctuate, basal portion of Sc not exceeding apex of basal cell, and hind legs with lateral spines. It has a mixture of ancestral characters shared with Hylicelloidea and Jurassic Procercopidae and some derived characters. Therefore, it is tentatively placed in Cercopoidea. A preliminary phylogram of Clypeata is presented based on the combination of fossil and morphological data.  相似文献   

7.
The genus Tournayellina (family Chernyshinellidae), important for stratigraphy of the Devonian–Carboniferous boundary interval, is revised. Species and generic morphological characters are considered and the species composition of the genus is revised. The evolution of the family is discussed and its geographical and stratigraphic distribution is examined. The species Tournayellina quadrilobata Postojalko, 1999 is redescribed in accordance with new data on its morphology. The new species T. intermedia Stepanova, sp. nov. is established.  相似文献   

8.
A new family of Laniatores, Gerdesiidae fam. nov., is proposed based on molecular and morphological evidence. Data also indicate that this new family is the sister family of Tricommatidae. Gerdesiidae fam. nov. has a disjunct distribution, occurring in northern South America (Peru, Brazilian Amazon) and at a spot in south‐eastern Brazil (Minas Gerais State). The new family is composed of two genera: Gerdesius Roewer, 1952 (type genus) and G onycranaus gen. nov. (type species G onycranaus androgynus sp. nov. ). We propose the synonymy of Huralvioides H. Soares, 1970 with Gerdesius Roewer, 1952 based on molecular and morphological evidence. Three new species are described: G erdesius mapinguari sp. nov. (type locality: Brazil, Amazonas, Manaus, Reserva Km 41); G onycranaus androgynus sp. nov. (type locality: Brazil, Minas Gerais, Conceição do Mato Dentro); and an obligate cave‐dwelling species, G onycranaus pluto sp. nov. (type locality: Brazil, Minas Gerais, Morro do Pilar). © 2015 The Linnean Society of London  相似文献   

9.
Sequence data from four DNA regions, namely, chloroplast trnL‐trnF and rps4, mitochondrial nad5, and nuclear 26S rDNA, were surveyed from 89 taxa traditionally associated with the Hookeriales, five Hypnales and five outgroups. Phylogenetic reconstruction was performed using the maximum parsimony and maximum likelihood optimality criteria and by Bayesian phylogenetic inference. Thirteen morphological characters were optimized on the resulting phylogeny using maximum likelihood. Inferences of character evolution based on the molecular phylogeny suggest that (1) the core of pleurocarpous mosses (i.e. the Hypnanae) is best defined and thus distinguished from the Ptychomnianae by smooth rather than furrowed capsules, (2) a synapomorphy for the Ptychomnianae is the short and double (or absent) costa and (3) the Hookeriales are defined by undifferentiated alar cells. The Ptychomniaceae plus Garovagliaceae are recognized as a single family in its own order, the Ptychomniales ord. nov. and superorder, the Ptychomnianae, superord. nov. This superorder is sister to the combined Hypnales and Hookeriales, i.e. the Hypnanae. The Hookeriales are interpreted as consisting of seven families, the Hypopterygiaceae, Saulomataceae fam. nov., Daltoniaceae, Schimperobryaceae fam. nov., Hookeriaceae, Leucomiaceae and Pilotrichaceae. The Adelotheciaceae are embedded within the Daltoniaceae and considered synonymous with that family. Within the Ptychomniaceae, Ptychomniella is raised from a subgenus of Ptychomnion to generic status. Euptychium setigerum and its monospecific section, Crassisubulata, are transferred to Garovaglia. Callicostella diatomophila is transferred to Diploneuron. Additional alterations at the generic level await more data.  相似文献   

10.
A new family of the order Rhabdomesida, Medvedkellidae fam. nov., is described. This family consists of a new genus, Medvedkella gen. nov., comprising three species transferred from the genus Rhombopora Meek, 1872: the type species M. riasanensis (Schulga-Nesterenko, 1955), M. diaphragmata (Schulga-Nesterenko, 1955), and M. mariae (Dunaeva, 1961). The morphogenesis of the first two species is studied. For the first time axial zooecia are revealed in the suborder Golgdfussitrypina, which existed in parallel with the suborder Rhabdomesina of the order Rhabdomesida. A hypothesis that the new family evolved from the subfamily Nicklesoporinae Gorjunova, 1985 of the family Goldfussitrypidae, 1985 is proposed. Some questions of the ecological adaptation of these bryozoans in the Late Carboniferous marine basin of the East European Platform are discussed.  相似文献   

11.
Acoela are marine microscopic worms currently thought to be the sister taxon of all other bilaterians. Acoels have long been used as models in evolutionary scenarios, and generalized conclusions about acoel and bilaterian ancestral features are frequently drawn from studies of single acoel species. There is no extensive phylogenetic study of Acoela and the taxonomy of the 380 species is chaotic. Here we use two nuclear ribosomal genes and one mitochondrial gene in combination with 37 morphological characters in an analysis of 126 acoel terminals (about one-third of the described species) to estimate the phylogeny and character evolution of Acoela. We present an estimate of posterior probabilities for ancestral character states at 31 control nodes in the phylogeny. The overall reconstruction signal based on the shape of the posterior distribution of character states was computed for all morphological characters and control nodes to assess how well these were reconstructed. The body-wall musculature appears more clearly reconstructed than the reproductive organs. Posterior similarity to the root was calculated by averaging the divergence between the posterior distributions at the nodes and the root over all morphological characters. Diopisthoporidae is the sister group to all other acoels and has the highest posterior similarity to the root. Convolutidae, including several "model" acoels, is most divergent. Finally, we present a phylogenetic classification of Acoela down to the family level where six previous family level taxa are synonymized.  相似文献   

12.
The Geonemertes problem (Nemertea)   总被引:2,自引:0,他引:2  
Janet  Moore  Ray  Gibson 《Journal of Zoology》1981,194(2):175-201
A new genus of monostiliferous hoplonemerteans, Pantinonemertes gen. nov., provides evidence for the separate evolution of terrestrial nemerteans. The genus is established for two new species found in Australia, P. enalios sp. nov., an intertidal form, and P. winsori sp. nov., which lives in fallen timber in the supralittoral brackish water regions of mangrove swamps. One only of the known species of land nemerteans, Geonemertes agricola from Bermuda, closely resembles these two species morphologically and is transferred to the new genus as Pantinonemertes agricola .
A re-examination of all the known species of Geonemertes has shown that two major groups can be distinguished on the basis of morphological characters. In one group the rhynchocoel musculature is in two distinct layers, a frontal organ is present, the mid-dorsal blood vessel has a single vascular plug, and the flame cells are binucleate and reinforced with cuticular support bars. It comprises the genus Pantinonemertes gen, nov, and the Pelaensis or Indopacific group of terrestrial nemerteans, for which the generic name Geonemertes is retained. In the second major group the rhynchocoel musculature is composed of interwoven longitudinal and circular fibres, there is no frontal organ, the mid-dorsal blood vessel bears two vascular plugs, and the flame cells are mononucleate and lack support bars. Five genera, three of which are new, are distinguished in this group. Australian species are united in the genus Argonemertes gen. nov., and New Zealand forms comprise the genus Antiponemertes gen. nov., while Acteonemertes bathamae from New Zealand and the Auckland and Ocean Islands remains in a separate genus. Geonemertes nightingaleensis is transferred to a new genus, Katechonemertes gen. nov., and for Geonemertes chalicophora a previously used generic name, Leptonemertes , is adopted.
A key to the terrestrial, brackish-water and marine nemertean species described in the present paper is provided.  相似文献   

13.
The morphology and molecular phylogeny of a new marine interstitial karyorelictean ciliate, Wilbertomorpha colpoda gen. nov., spec. nov., isolated from a sandy beach at Qingdao, China, are investigated. The ciliature is mainly on the right surface with the left surface barren except for a single marginal kinety, which is typical of the order Loxodida. Nevertheless, other morphological features, such as the highly reduced buccal structure, the absence of a buccal cavity and the presence of extremely specialized cortical granules, prevent its assignation to any known family. Furthermore, the secondary structure of the variable region 2 of the SSU rRNA gene is unique among loxodids. Thus, we establish a new family, Wilbertomorphidae fam. nov. for the genus Wilbertomorpha. Phylogenetic analyses based on SSU rRNA gene sequence data suggest that this taxon is a sister group to the family Geleiidae which belongs to the order Protoheterotrichida. However, morphologically Wilbertomorpha bears a much stronger resemblance to Loxodidae which belongs to the order Loxodida. Based on these findings, we tentatively place Wilbertomorphidae nov. fam. incertae sedis within Karyorelictea.  相似文献   

14.
15.
Sequence data from the 18S nrDNA (SSU) and 28S nrDNA (LSU) regions of isolates of Phoma section Paraphoma were compared with those of representative isolates of the morphologically similar anamorph genera Pleurophoma and Pyrenochaeta and of the type species of Phoma sections Phoma, Pilosa and Plenodomus. Phoma section Paraphoma was found to be highly polyphyletic within the Pleosporales and only distantly related to Phoma section Phoma. The genus Paraphoma, which is based on Paraphoma radicina, is reintroduced in the Phaeosphaeriaceae with two additional taxa. The new genera Setophoma and Neosetophoma, type species Setophoma terrestris comb. nov. and Neosetophoma samarorum comb. nov., are introduced and represent species that are closely related to Paraphoma but differ based on morphological characters and molecular phylogeny. Phoma coonsii is transferred to genus Chaetosphaeronema that also belongs to the Phaeosphaeriaceae. Pyrenochaetopsis gen. nov. is introduced to accommodate the type species Pyrenochaetopsis leptospora comb. nov., as well as several other species formerly accommodated in Phoma and Pyrenochaeta. Pyrenochaetopsis is closely related to Pyrenochaeta and classified in the Cucurbitariaceae. Pleurophoma cava is transferred to genus Pyrenochaeta. The new genera elucidate the confusing taxonomy of species in genera Phoma, Pyrenochaeta and Pleurophoma and recognize monophyletic genera with distinct teleomorph affinities.  相似文献   

16.
Morphologically complex bryozoans from the Upper Devonian and Lower Carboniferous of Eurasia that some research workers include in the order Rhabdomesida and others place in the order Trepostomata are studied. The axial zooecium is demonstrated to be of zooidal nature. A new family, Coelotubuliporidae fam. nov., is established and its position in the order Trepostomata is substantiated. It includes two genera (one new), 11 species (1 new), and four subspecies. Diagnoses of a new family, Coelotubuliporidae, the genus Coelotubulipora Yang, Hu et Xia, 1988, and a new genus, Dunaevella Gorjunova gen. nov., are presented. The following species are described: Coelotubulipora irinae Gorjunova, sp. nov., Dunaevella shishovae (Schulga-Nesterenko, 1955), and D. peristomata (Schulga-Nesterenko, 1955). The emergence of axial zooecia in representatives of the order Trepostomata is considered as one of the evolutionary ways of bryozoans due to morphological parallelisms. It is shown that data presented on the stratigraphic range and paleogeography of the family Coelotubuliporidae are of great significance for solving the problems of biostratigraphy and correlation of deposits of the Upper Devonian and Lower Carboniferous of Eurasia.  相似文献   

17.
All global genera of the fly family Conopidae are revised here. A cladistic analysis of 117 morphological characters recorded from 154 species, including representatives of 59 genera and subgenera, recovers a phylogenetic hypothesis for the family. This hypothesis is used as the basis of a new classification for the family. Both Sicini and Zodionini are removed from Myopinae and elevated to subfamilial status. A new tribe, Thecophorini, is proposed within Myopinae to accommodate Thecophora, Scatoccemyia, and Pseudoconops. Two genera, Pseudomyopa and Parazodion, are removed from Dalmanniinae and placed in Myopinae and Zodioninae, respectively. Conopinae is divided into 11 tribes, seven of which are newly described (Asiconopini, Caenoconopini, Gyroconopini, Microconopini, Neoconopini, and Siniconopini). Some examined species are transferred to different or new genera and subgenera. A new genus, Schedophysoconops gen. nov. , and subgenus Asiconops (Aegloconops) subgen. nov. within Conopinae are described. A review of character evolution and phylogeography is included in light of the new classification. A catalogue of all genus‐group names is included with new emendations noted.  相似文献   

18.
Data on the external morphology are reviewed and new information is provided about the structure of the first naupliar instar of Parthenopea subterranea Kossmann, a rare and poorly known species of rhizocephalan barnacles. The taxonomic position of P. subterranea, which has so far been uncertain, is discussed. A new family, Parthenopeidae fam. nov., is erected to include a single genus, Parthenopea, with a single species, P. subterranea. The distinctive characters of the new family are described.  相似文献   

19.
The scale insect genus Limacoccus and its four palm pest species are revised and all instars with sexual dimorphism are described and illustrated. A key to Limacoccus species is provided. The unique life-history of this genus with construction of a protective tunnel by the second-instar female is described. A cladistic analysis of Limacoccus and eleven representative species of Diaspididae, Halimococcidae, Phoenicococcidae and Beesoniidae, was undertaken using fifty-four traditional and new characters from first and second instars and adult females. Character polarity was determined by outgroup comparison with Margarodidae, Pseudococcidae, Eriococcidae and Asterolecaniidae as outgroups. Nine most parsimonious trees were found. Analysis of the eleven terminal taxa of the strict consensus tree using Phoenicococcidae, Halimococcidae and Diaspididae as outgroups produced one parsimonious tree. As result of this analysis, Limacoccus is believed to be a monophyletic group of characterized by seven autapomorphies and is assigned to the family Beesoniidae fam.rev. The redefined family is divided into two tribes: Beesoniini stat.nov. with genera Beesonia and Mangalorea and Limacocciini stat.nov. with the genus Limacoccus. The Beesoniidae are here regarded as a sister group of Phoenicococcidae.  相似文献   

20.
DICK, M. VV., 1986. A new family and a new genus for two taxa previously assigned to Apodachlyella completa (J. E. Humphrey) H. Indoh (Peronosporomycetidae: Leptomitales) . At present two distinct taxa are referrable to Apodachlyella completa. New genus and species names (I'lerogone helodes M. W. Dick genus & sp. nov.) are necessary for the taxon reported from the British Isles. Confirmation of the unique wall membranes in the antheridia and oogonia is used to justify the placement of A. completa in a new, monotypic family of the Leptomitales (Apodachlyellaceae M. W. Dick fam. nova). Plerogone is placed provisionally in the Leptomitaceae.  相似文献   

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