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891.
Litter‐trapping plants have specialized growth habits and morphologies that enable them to capture falling leaf litter and other debris, which the plants use for nutrition after the litter has decayed. Litter is trapped via rosettes of leaves, specially modified leaves and/or upward‐growing roots (so‐called ‘root baskets’). Litter‐trappers, both epiphytic and terrestrial, are found throughout the tropics, with only a few extra‐tropical species, and they have evolved in many plant families. The trapped litter mass is a source of nutrients for litter‐trapping plants, as well as food and housing for commensal organisms. Despite their unique mode of life, litter‐trapping plants are not well documented, and many questions remain about their distribution, physiology and evolution.–© 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 554–586.  相似文献   
892.
New isolated petrosals from the Itaboraí beds of Brazil (late Palaeocene or early Eocene) are here described and referred to the early diverging litoptern Miguelsoria parayirunhor, based on phylogenetic, size, and abundance arguments. Both the external and internal anatomy of these specimens were investigated, which for the first time document many details of the auditory region of a Palaeogene litoptern. Our cladistic analysis, which included our new observations, failed to recover a monophyletic Litopterna but did not exclude it. A constrained analysis for the monophyly of this order showed that several features such as a (sub)quadrangular and anteroposteriorly elongated tensor tympani fossa and a large notch in the vicinity of the external opening of the cochlear canaliculus may constitute synapomorphies for Litopterna. The evolution of several other auditory characters amongst Litopterna is discussed and the relative dimensions of the inner ear and surrounding petrosal in the group were also investigated. This allowed detection of negative allometry of the bony labyrinth within the petrosal, which was confirmed by measurements and regression analysis across a larger sample of placental mammals. This scaling effect probably has an important influence on several characters of the bony labyrinth and petrosal, amongst which are the length of the vestibular aqueduct and cochlear canaliculus. It demonstrates that many aspects of the morphological variation of the bony labyrinth need to be thoroughly investigated before being incorporated into phylogenetic analyses. © 2015 The Linnean Society of London  相似文献   
893.
Most nominal fan worm species belonging to the genus Parasabella Bush, 1905, and Sabellomma Nogueira, Fitzhugh & Silva‐Rossi, 2010 (Sabellidae, Annelida) lack unique morphological diagnostic features. Species diagnoses rely on a combination of attributes, often making reference to characters that are qualitatively or quantitatively continuous. This, together with a lack of knowledge about phenotypic intraspecific variation in most species, suggests that the sole use of morphological features is insufficient to identify and characterize some of these species. Examination of collections revealed that Parasabella is a common and diverse group of sabellids along the Australian coastline, although it had only been recorded here twice. The genus Sabellomma is here reported in Australia for the first time. Comparison of morphological data and nuclear (internal transcribed spacer) and mitochondrial (cytochrome oxidase I) DNA sequence data of 30 terminals in a range of analyses allowed us to assess the monophyly of Parasabella and its sister‐group relationship with Sabellomma and to examine some of the species boundaries and genetic diversity within lineages. The combined sequence data results indicate the presence of seven distinct genetic Parasabella lineages in Australia, four of which are assigned to previously described species (three are new records for Australia), and two are considered as a complex of species sharing a unique combination of characters, one of which is described as new. Another Parasabella species with distinct atypical radiolar eyes and a species of Sabellomma are also described as new. © 2015 The Linnean Society of London  相似文献   
894.
Owing to the reinterpretation of its morphological synapomorphies, the taxonomic composition of the Ectateus generic group had been ambiguous. The present study scrutinized all existing taxonomic concepts of the group based on a cladistic analysis of the adult morphology of all of the Afrotropical platynotoid Platynotina genera. The phylogenetic relationships were reconstructed using parsimony and Bayesian inference. The results show that all previous taxonomic concepts of the Ectateus generic group concerned paraphyletic entities. The cladistic analysis revealed the following synapomorphies for the taxon: (1) presence of basal indentations of the pronotal disc, (2) ratio of prothorax width to its maximal height > 6.0, and (3) ratio of maximal height of the prothorax to total height < 0.3. Moreover, phylogenetic studies revealed the existence of the Upembarus generic group, a sister‐taxon group to the Ectateus generic group, within the Afrotropical platynotoid Platynotina. Autapomorphic and synapomorphic character mapping show that several taxonomic and nomenclatural changes are needed to consider the particular generic‐level entities traditionally assigned to Afrotropical platynotoid Platynotina as monophyletic lineages. The following taxonomic and nomenclatural adjustments are made in this paper: P teroselinus gen. nov. is erected to accommodate a single species that was previously assigned to Zidalus: Pteroselinus insularis comb. nov. Additionally, the following synonymies are proposed: Anchophthalmops (= Platykochius syn. nov. ), Angolositus (= Aberlencus syn. nov. , = Platymedvedevia syn. nov. ), Glyptopteryx (= Microselinus syn. nov. , = Quadrideres syn. nov. , = Synquadrideres syn. nov. ). In addition, Kochogaster is lowered in rank and is treated as one of the subgenera of Anchophthalmus. Moreover, Pseudoselinus is treated as a subgenus of Upembarus. An identification key to all Afrotropical platynotoid Platynotina genera and subgenera is presented. Zoogeographical analyses revealed the following dispersal barriers for the Ectateus generic group: (1) the Sahara (northern barrier); (2) the dry ecosystems of Botswana, Namibia, and South Africa (southern barrier); and (3) the Congolian rainforests (internal distributional gap). The ancestor of the taxon probably originated in East African ecoregions that predominantly contained wattletrees (acacias) and Commiphora Jacq. Moreover, past climate changes seem to have had a great impact on the observed generic distribution. © 2015 The Linnean Society of London  相似文献   
895.
Reconstructing the phylogeny of the sexually deceptive orchid genus Ophrys is crucial to our understanding of the evolution of its complex floral morphology. Molecular phylogenetic analyses showed that section Pseudophrys forms a well supported clade with Ophrys bombyliflora, O. tenthredinifera and O. speculum, but were unable to elucidate the relationships between these four groups of taxa. Here we conduct a morphological phylogenetic analysis of this unresolved clade of Ophrys based on a data matrix of 45 macro‐ and micromorphological and anatomical floral characters, using maximum parsimony and Bayesian inference. Our cladistic analysis yielded a single most parsimonious tree and a Bayesian 50% majority‐rule consensus tree which differed in their overall topology but agreed that O. tenthredinifera and O. bombyliflora are not sister groups. The phylogenetic placement of O. tenthredinifera was ambiguous since it shares six valid synapomorphies each with the cluster of O. speculumO. bombyliflora and with section Pseudophrys. In contrast, O. bombyliflora is most likely the sister group to O. speculum, a finding that rejects an earlier morphological phylogenetic hypothesis and favours the existing molecular trees based on nuclear ITS rather than plastid data. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 179 , 454–476.  相似文献   
896.
The male genitalia of 13 species from four genera of Astathini were described and analyzed. The result showed that five genital characters, such as shape of the apex of 8th abdominal tergaum and sternum, ratio of the length of lateral lobes to tegmen, can be used to identify genera of Astathini; six characters, such as ratio of the length of lateral lobes to tegmen, ratio of the length of roof to lateral lobes, shape of the apex of ventral plate of median lobe, can be used to identify species in Bacchisa.  相似文献   
897.
丝状真菌(Filamentous fungi)的发酵生产通常具有较高的工业应用价值,但其菌体形态是一个区别于其他非丝状菌的一个重要发酵指标。针对目前形态分析的瓶颈,本研究使用琼脂糖凝胶对黑曲霉菌形进行固定,利用平板实现菌球样本的大量制备,并结合图形处理软件自建自动化处理程序,实现了大量准确可靠的菌体形态参数的获得,大大增加了形态数据处理通量及准确度。应用该方法于黑曲霉发酵生产糖化酶过程中不同供氧水平及剪切水平下菌体形态的研究,通过大量形态数据定量阐明了黑曲霉在不同剪切水平下的分区域形态分布特性,为进一步工业过程的形态优化提供了重要的研究方法。  相似文献   
898.
899.
900.
There remain some difficulties in delimitation of related genera or sibling species for cantharid beetles, because the traditionally taxonomic method and morphological characters have not been updated or introduced. In the present study, we firstly use the landmark-based geometric morphometrics to analyze and compare the hind wings of nine species belonging to three genera of Cantharinae to ascertain whether this approach may be used as a reliable method in the study of the taxonomy of this group. The results show that the shape differences of the hind wings among genera seem more variable than that within each genus, and the variations for each species are different from one another, as shown in the principal component analyses. And the canonical variates analyses show that there are significant differences among the genera and the species of each genus, which demonstrates that the hind wing shape can be diagnostic for both generic and specific identification of the cantharid beetles. This study sheds new light into clarifying the taxonomic uncertainties of Cantharidae, and lays a foundation for further studies on the evolution of the cantharid hind wing shape.  相似文献   
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