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1.
Four species of turbellarian temnocephalan symbionts (Platyhelminthes: Temnocephalida) are reported for the first time from the external surfaces of Cherax quadricarinatus, a freshwater crayfish from northern Australia. Three of these species — Temnocephala rouxii Merton, 1913, Notodactylus handschini (Baer, 1945), and Diceratocephala boschmai Baer, 1953 — are known previously from related crayfish in New Guinea. The newly discovered fourth species, Decadidymus gulosus n. gen., n. sp., has an unusual combination of characters linking it with both the Temnocephalidae and the Scutariellidae. Together the four species possess an array of characters that challenges current concepts of families in the order. D. boschmai has an almost completely ciliated epidermis, a feature otherwise unknown in the order.  相似文献   

2.
The Empis macrorrhyncha group (Diptera: Empididae) from cool to warm temperate areas of South America and Australia is diagnosed and cladistically analysed, and five new species, Empis animosa sp.n. , E. austera sp.n. , E. maculosa sp.n. , E. occidentalis sp.n. and E. pedivillosula sp.n. , are described. Cladistic analysis of 23 adult morphological characters for 14 species of the group generated a single tree of 28 steps (CI = 0.82; RI = 0.93). Monophyly was established on the basis of a single apomorphy, possession of a bilobed cercus of the male hypopygium. Three main clades were inferred: clade 1 included three Patagonian and a single southwestern Australian species; clade 2 included two species from southeastern Australia; clade 3 included a large Patagonian group of five species and a single southeastern Australian species. The E. fulvicollis complex (clade 1) is a sister‐group of the E. macrorrhyncha complex (clades 2 + 3). A provisional historical biogeographic hypothesis is advanced correlating the appearance of the South American and Australian sister lineages with the timing of the break‐up of Gondwana.  相似文献   

3.
Phylogenetic relationships of ten wild species and several cultivars ofForsythia were reconstructed based on the chloroplast (cp) DNA variation. A total of 216 cpDNA variants, 44 of which were potentially phylogenetically informative, was detected using 24 restriction endonucleases. Phylogenetic analysis usingFontanesia andAbeliophyllum as outgroups revealed four well defined species groups in the genus: 1)F. suspensa, 2)F. europaea — F. giraldiana, 3)F. ovata — F. japonica — F. viridissima, and 4)F. koreana — F. manshurica — F. saxatilis. The amount of support for each monophyletic group was evaluated by various methods including character number, decay analysis, parsimony bootstrapping, Neighbour-Joining (NJ) — bootstrapping, NJ-jackknifing, and the topology-dependent permutation tail probability (T-PTP) test. The data do not support the hybrid origin ofF. intermedia fromF. suspensa andF. viridissima. The disjunctly distributed European species,F. europaea, was identified as a sister species of the ChineseF. giraldiana and it was probably derived through recent long distance dispersal.  相似文献   

4.
The phylogenetic relationships of species attributed to the ornithopod family Hypsilophodontidae are evaluated using morphological characters from the skull, dentition, and postcranium. Based on our analyses, Hypsilophodontidae constitutes a monophyletic taxon that comprises the sister taxon to Iguanodontia, together forming Euornithopoda. Three clades within the family are consistently demonstrated: Zephyrosaurus schaff+Orodromeus makelai, Parksosaurus warreni+Hypsilophodon foxii and Yandusaurus hongheensis+Othnielia rex. Thescelosaurus neglectus is the sister taxon to these six genera and constitutes the basal hypsilophodontid. Tenontosaurus tilletti is the basal member of Iguanodontia, with species of Dryosaurus and Camptosaurus as higher taxa within the clade. To understand the effects missing data may have on tree topology, tree length, and consistency indices, poorly represented characters were secondarily removed from the character matrix. In these analyses, all relationships remain stable, but tree length and consistency index decrease with increasingly more complete culled data sets. An average of 42.5 million years is accumulated as minimal divergence time for the hypsilophodontid and basal iguanodontian relationships described here. These figures underscore the large amount of hypsilophodontid evolution yet unaccounted for in the fossil record.  相似文献   

5.
Phylogenetic relationships within the genus Muscisaxicola, a primarily Andean group of tyrant-flycatchers, were studied using complete sequences of the mitochondrial genes COII and ND3. Relationships among Muscisaxicola species were found to differ substantially from those of previous views, suggesting convergence in traditional avian taxonomic characters within the genus. The 11 species of large, gray, “typical” Muscisaxicola flycatchers (including M. grisea, newly restored to species status) formed a distinct clade, consisting of two major groups: a clade of 6 species breeding primarily in the central Andes and a clade of 5 species breeding primarily in the southern Andes. The other 2 species traditionally placed in this genus, M. fluviatilis, an Amazonian species, and M. maculirostris, were both rather divergent genetically from the typical species, although M. maculirostris may be the sister taxon to the typical clade. The patterns of sympatry exhibited by Muscisaxicola species in the high Andes appear to be the consequence of speciation and secondary contact within regions of the Andes, rather than a result of dispersal between regions. Diversification of the typical Muscisaxicola species appears to have occurred during the middle and late Pleistocene, suggesting generally that taxa of the high Andes and Patagonia may have been greatly influenced by mid-to-late Pleistocene events. There were likely several independent developments of migration within this genus, but migration is probably ancestral in the southern clade, with subsequent loss of migration in two taxa.  相似文献   

6.
Sperm morphology of orthalicid gastropods Clessinia pagoda, Spixia tucumanensis, Plagiodontes daedaleus (Odontostominae) and Drymaeus hygrohylaeus, D. poecilus, Bostryx stelzneri (Bulimulinae) are examined and described for the first time using transmission electron microscopy. Spermatozoa show the general characteristic of Pulmonata: an acrosomal vesicle, sperm nucleus helical, mitochondrial derivative forming a continuous sheath with paracrystalline material and coarse fibers associated with axonemal doublets. Features in the acrosomal complex and shape of the nucleus distinguish orthalicid sperms from other stylommatophoran. The acrosomal pedestal is traversed by fine striations in all species examined except in S. tucumanensis. The structure and thickness of the perinuclear sheath with a single or double layer of electron-dense material ensheathing the nuclear apex is characteristic of the group. The presence of a subnuclear ring in Drymaeus, Bostryx and Clessinia species is also reported. A data matrix of eleven species per 34 characters (16 sperm plus 18 anatomical and shell characters) from orthalicids plus other stylommatophoran and systellommatophoran representative species was constructed. Three cladistic analyses (sperm-based, anatomical-based and a combined sperm + anatomical-based) were performed to test the phylogenetic potential of sperm ultrastructure in orthalicid systematics and understand how sperm characters affect the topology and resolution of the obtained trees. Stylommatophora resulted in a monophyletic clade in the sperm-based and in the combined-character analysis. Orthalicidae is monophyletic only in the combined-character cladogram. Within Orthalicidae, Odontostominae is recovered as a monophyletic clade in all analyses, while Bulimulinae is paraphyletic in all trees except in the combined phylogeny. The present study and cladistic analyses performed support the hypothesis that characters on sperm ultrastructure are informative for stylommatophoran systematic and phylogenetic approaches, providing synapomorphies at familiar, subfamiliar and generic level.  相似文献   

7.
8.
A phylogeny of the Neotropical members of the Tribe Troidini (Lepidoptera: Papilionidae) was obtained with sequences of three protein-coding genes: two mitochondrial (COI and COII), and one nuclear (EF-1α). Parsimony and Bayesian analyses of 33 taxa resulted in very similar trees regardless of method used with the 27 troidines always forming a monophyletic clade. Within Troidini, the genus Battus is sister group to the remaining troidines, followed by a clade formed by the Paleotropical taxa (here represented by three exemplars). The genus Euryades is the next branch, and sister group of Parides. The genus Parides is monophyletic, and is divided into four main groups by Maximum Parsimony analysis, with the most basal group composed of tailed species restricted to SE Brazil. Character optimization of ecological and morphological traits over the phylogeny proposed for troidines indicated that the use of several species of Aristolochia is ancestral over the use of few or a single host-plant. For the other three characters, the ancestral states were the absence of long tails, forest as the primary habitat and oviposition solitary or in loose group of several eggs.  相似文献   

9.
Taxonomic analysis of a group of morphologically similar ponyfishes (Perciformes: Leiognathidae) establishes the Leiognathus splendens complex comprising four valid species: L. jonesi James, 1971, widely distributed in the Indo-West Pacific, from Mauritius to Papua New Guinea, north to Hainan I. (China), and south to Brisbane, Australia; L. kupanensis sp. nov., currently known only from Kupang, Timor, Indonesia; L. rapsoni Munro, 1964, currently known only from India, Indonesia, and Papua New Guinea, and L. splendens Cuvier, 1829, widely distributed in the eastern Indian and western Pacific oceans, from India to Papua New Guinea, and from southern Japan to northern Australia. The L. splendens complex can be defined by the following combination of characters: body depth 42–60% of standard length; mouth protruding downward; slender, minute teeth uniserially on jaws; lower margin of orbit above the horizontal through the gape when mouth closed; breast almost completely scaled; lateral line complete, and a dark blotch on top of spinous dorsal fin. Diagnostic characters of the members are as follows: L. jonesi—anterior dorsolateral body surface with a semicircular naked area on nape, and a paler dark blotch on spinous dorsal fin; L. kupanensis—anterior dorsolateral body surface widely naked; L. rapsoni—cheek scaled; L. splendens—anterior dorsolateral body surface completely scaled and a jet black blotch on spinous dorsal fin.  相似文献   

10.
Pollination ofDianthus gratianopolitanus was studied in a population of the Swiss Jura mountains. Pollinators of this plant species are reported here for the first time. The flowers were not only visited by butterflies as postulated in the literature, but also by diurnal hawkmoths (Macroglossum stellatarum) and by diurnal and nocturnal noctuid moths. — Nectar is sucrose-dominant, the sugar concentration is moderate but the amino acid concentration is high. Nectar characteristics correspond well with the syndrome ofLepidoptera-pollinated flowers. — Field observations and flower characters (colour, range of the calyx length) suggest thatDianthus gratianopolitanus is an intermediate species in the transition of butterfly to moth pollination. — Lack of reproductive success inDianthus gratianopolitanus can not be attributed to lack of suitable pollinators.  相似文献   

11.
Multivariate analyses of similarities between species of the Ostertagiinae were performed on the data from 585 publications. The environmental factors were 12 climates and host-specificity in ruminants (40 species) for 16 species of ostertagiines. This approach can be a useful tool for distinguishing morphs from species. The following pairs (species and its possible morph) of ostertagiines are proposed: Ostertagia ostertagi — O. lyrata, O. leptospicularis — O. kolchida, O. gruehneri — O. arctica, Teladorsagia circumcincta — T. trifurcata, Marshallagia marshalli — M. occidentalis, Spiculopteragia boehmi — S. mathevossiani, and S. asymmetrica — S. quadrispiculata.  相似文献   

12.
The marmosets, tribe Callitrichini, are the most speciose clade in the subfamily Callitrichinae, containing 21 species. However, there is no consensus among molecular and morphological systematists as to how many genera should be recognized for the group. To test the morphological support for the alternative generic classifications, this study presents a comprehensive phylogenetic analysis. It is the first such analysis to include all 21 species and employ continuous and discrete osteological, pelage and tegument, karyological and vocal characters. This dataset was combined with nucleotide sequences from two mitochondrial and four nuclear regions. Separate analyses showed that, among morphological datasets, osteological characters were best at solving relationships at more inclusive levels, whilst pelage characters were most informative at the interspecific level. This suggests the presence of different transformation rates for the two character sets. When a single most parsimonious tree was obtained using the 83‐character matrix, three main clades were identified, supporting the division of the marmosets into three genera: Callithrix, Cebuella and Mico. The total evidence analysis that included an additional 3481 molecular characters corroborated most of the morphology‐based clades and also supported a three‐genus classification of the marmosets. This is the first morphological study to support an Amazonian marmoset clade (Cebuella Mico), which is also strongly supported in exclusively molecular phylogenies, and to synonimize Callibella under Mico.  相似文献   

13.
The late Cretaceous hadrosaurids were the most specialized and diverse clade of ornithopod dinosaurs. Parsimony and Bayesian methods were implemented to elucidate the phylogenetic relationships of all hadrosaurid species. Traditional and geometric morphometrics were applied to discover patterns of variation containing phylogenetic information. In total, 286 phylogenetically informative characters (196 cranial and 90 postcranial) were defined and documented: the most extensive character data set ever constructed for hadrosaurid dinosaurs. Of these, 136 characters were used for the first time in phylogenetic analysis of these ornithopods, and 93 were modified from those of other authors. Parsimony and the Bayesian analysis (using the Mk model without the gamma parameter) confirmed the split of hadrosaurids into Saurolophinae and Lambeosaurinae. Saurolophines included a major clade composed of the ProsaurolophusSaurolophus and the KritosaurusGryposaurusSecernosaurus subclades. Edmontosaurus and Shantungosaurus were recovered outside the major clade of saurolophines. The Brachylophosaurus clade was recovered as the most basal clade of saurolophines in the parsimony analysis, whereas following the Bayesian analysis it was recovered as the sister clade to the KritosaurusGryposaurus–Secernosaurus clade. These two analyses resulted in a Lambeosaurinae composed of a succession of Eurasian sister taxa to two major clades: the Parasaurolophus clade and the Hypacrosaurs altispinusCorythosaurus clade. In contrast, the Bayesian analysis using the Mk model with the gamma parameter included, resulted in an unbalanced hadrosauroid tree, with a paraphyletic Saurolophinae, and with the Prosaurolophus clade, Edmontosaurus, and Shantungosaurus as successively closer sister taxa to Lambeosaurinae. Based on the strict reduced consensus tree derived from the parsimony analysis, Hadrosauridae was redefined as the clade stemming from the most recent common ancestor of Hadrosaurus foulkii and Parasaurolophus walkeri. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 159 , 435–502.  相似文献   

14.
Recent study on Lasiopodomys (Stenocranius) gregalis has revealed four clear mitochondrial lineages with differences exceeding the species level. The most divergent is the clade from south‐eastern Transbaikalia. Multilocus (six nuclear genes), morphological (dental characters of m1 and M3) and behavioural (breeding experiments) analyses were conducted to test the hypothesis that L. gregalis is a complex of two cryptic species. All of the applied methods distinguish the independent status of voles from south‐eastern Transbaikalia. This clade occupies a portion of the distribution range of the currently valid subspecies L. g. raddei including its terra typica. According to the results of cyt b analysis, the lectotype of L. g. raddei belongs to the Transbaikal clade. We re‐establish the species status for the taxon Lasiopodomys raddei including populations from south‐eastern Transbaikalia, as a cryptic species of the narrow‐headed vole complex.  相似文献   

15.
Andreas Bick   《Zoologischer Anzeiger》2004,243(1-2):53-63
The fabriciin sabellid species, Fabricia nigra Langerhans, 1880 from the Macaronesian region, is assigned to the genus Pseudoaugeneriella Fitzhugh, 1998, based on information provided by newly collected specimens. The species is redescribed, including the variability of key characters. Moreover, structures of the anterior end — dorsal lips, ventral filamentous appendages, peristomial rings — of Pseudoaugeneriella nigra and other species of Fabriciinae are studied histologically and by means of SEM. The systematic significance of these characters in Fabriciinae is discussed.  相似文献   

16.
This study investigates the molecular phylogeny of seven lionfishes of the genera Dendrochirus and Pterois. MP, ML, and NJ phylogenetic analysis based on 964 bp of partial mitochondrial DNA sequences (cytochrome b and 16S rDNA) revealed two main clades: (1) “Pterois” clade (Pterois miles and Pterois volitans), and (2) “Pteropterus–Dendrochirus” clade (remainder of the sampled species). The position of Dendrochirus brachypterus either basal to the main clades or in the “Pteropterus–Dendrochirus” clade cannot be resolved. However, the molecular phylogeny did not support the current separation of the genera Pterois and Dendrochirus. The siblings P. miles and P. volitans are clearly separated and our results support the proposed allopatric or parapatric distribution in the Indian and Pacific Ocean. However, the present analysis cannot reveal if P. miles and P. volitans are separate species or two populations of a single species, because the observed separation in different clades can be either explained by speciation or lineage sorting. Molecular clock estimates for the siblings P. miles and P. volitans suggest a divergence time of 2.4–8.3 mya, which coincide with geological events that created vicariance between populations of the Indian and Pacific Ocean.  相似文献   

17.
In contrast to low diversity seen in many Australian rainforest squamate genera, sclerophyll adapted groups—such as Carlia—show signs of faster diversification. Here we expand upon a previous single-locus mitochondrial DNA phylogenetic study of Carlia which described a major polytomy at an intermediate level of divergence. With additional mtDNA data, two nuclear intron loci and comprehensive taxonomic coverage, we provide support, congruent across loci, for the existence of three major clades. In doing so we recognise three genera for the ‘Carlia group of skinks’: clade 1, Carlia Gray, 1845; 2, Lygisaurus De Vis, 1884 (includes all species formerly known as Lygisaurus, and also includes C. parrhasius); 3, Liburnascincus Wells and Wellington, 1984 (consisting of three boulder-dwelling species). Remaining regions of low bootstrap and posterior probability support are associated with short internodes and apparent conflict among loci, as inferred by Partition Branch Support. Likelihood-based diversification-rate analysis rejects constant rate models, and indicates that Carlia underwent a period of relatively rapid diversification early in the evolution of the group, a rate 3–4 times faster than subsequent rates, and faster than comparable wet forest skinks.  相似文献   

18.
A phylogenetic analysis of Euphorbiaceae sensu stricto is presented using sequences from rbcL, atpB, matK and 18S rDNA from 85 species and 83 genera. The combined analysis of four molecular markers resulted in only one most parsimonious tree and also generated new supported clades, which include Euphorbioideae + Acalyphoideae s.s., subclades A2 + A3, subclades A5 + A6 and a clade uniting subclades A2–A8 within Acalyphoideae s.s. A palisadal exotegmen is a possible synapomorphy for all the Euphorbiaceae, except for the subfamily Peroideae. The presence of vascular bundles in the inner integument and a thick inner integument were shown to be synapomorphies for the clade of inaperturate and articulated crotonoids and for the large clade of Euphorbioideae, Acalyphoideae s.s., inaperturate and articulated crotonoids, respectively. Characters of the aril and vascular bundles in the outer integument are discussed. The selected embryological characters were seen to be highly correlated with the molecular phylogeny. When the results of molecular phylogenetic analysis of a previous study and this study were adjusted along with the selected embryological characters, all clades within Euphorbiaceae were supported except for a clade comprising Euphorbioideae + Acalyphoideae s.s. + inaperturate crotonoids + articulated crotonoids + Adenoclineae s.l. and a clade uniting subclades A4–A8 within Acalyphoideae s.s. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

19.
We determined DNA sequences spanning the 1.8-kb long intron 1 of the interstitial retinol-binding protein nuclear gene (IRBP) for Callithrix geoffroyi, Callithrix humeralifer, and Callithrix argentata. With the 22 previously determined IRBP intron 1 sequences—21 from the 16 currently recognized genera of New World monkeys—the enlarged IRBP data represent for the marmoset genus Callithrix both its argentata and its jacchus species groups. Maximum-parsimony and neighbor-joining trees, constructed for the 25 aligned IRBP intron 1 sequences, support a provisional phylogenetic classification with three families: Atelidae, containing subfamily Atelinae; Pitheciidae, containing subfamily Pitheciinae; and Cebidae, containing subfamilies Cebinae, Aotinae, and Callitrichinae. In order to have taxa at the same hierarchical rank at equivalent age, this classification has all living callitrichines in a single tribe, Callitrichini, with four subtribes: Saguinina (Saguinus), Callimiconina (Callimico), Leontopithecina (Leontopithecus), and Callitrichina (Callithrix with the pygmy marmoset, Cebuella pygmaea, merged into it). The DNA evidence shows not only that Callithrix must include C. pygmaea to be monophyletic but also that the times of separation of pygmaea and the argentata and jacchus species groups from one another are to be expected (<5 Ma—million years ago) for species in a single genus. On relating the time course of the ceboid radiation to biogeographic information, it appears that in mid-Miocene times (10–11 Ma) a basal callitrichin stock branched into the ancestral population of Saguinus in one clade and the ancestral population of Leontopithecus and Callimico–Callithrix (or Leontopithecus–Callimico and Callithrix) in another clade. The proto-lion tamarins migrated south and eastward, where they were isolated in refugia, becoming the genus Leontopithecus. The stock remaining in Amazonia gave rise to present-day Callimico and Callithrix. The latter genus occupied a vast geographic area, giving rise to the argentata and pygmaea groups in Amazonia and to the jacchus group in central and eastern Brazil.  相似文献   

20.
Hexokinases (EC 2.7.1.1) were genetically analyzed in the mosquitoAedes togoi by agar gel electrophoresis. Enzyme activity was observed anodally in one major banding region (HK-1) on the gel and in another faintly stained region (HK-2). A total of six bands was detected in the HK-1 region. All six bands could be detected in three body parts, head, thorax, and abdomen, of adults with different banding intensities. The third and fourth bands, numbered from the more anodal side, showed the broadest substrate specificity and the greatest enzyme activity throughout development. Genetic analysis of the six HK-1 bands was undertaken on the hypothesis of a single gene locus (or three extremely tightly linked loci). The analysis gave the following gene order:HK-1—4.2±1.8 (recombination units±SE)—To-2Odh-2—29.5±2.5—sex (M/m)—s. A comparison is made of gene loci for hexokinases among the mosquito speciesCulex pipiens, Aedes aegypti, and this species, along with a comment on linkage relationships betweenHk andOdh (octanol dehydrogenase) loci in threeAedes species.This research was supported by National Institutes of Health Grant AI 16983 and a Grant-in-Aid for Co-operative Research (57340033) from the Ministry of Education, Science and Culture, Japan.  相似文献   

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