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1.
The taxonomic value and evolutionary significance of 30 leaf epidermal characters from 238 samples representing 127 species of all seven genera in the tribe Gaultherieae (Ericaceae) and two outgroup genera were investigated by scanning electron microscopy. The character states were coded and optimized onto a maximum‐likelihood tree based on previous molecular data with Fitch parsimony and hierarchical Bayesian analysis to trace the evolution of character states throughout all internodes in the phylogenetic tree for Gaultherieae. Leaf epidermal characters were found to be largely consistent within species, but highly variable at interspecific and higher taxonomic levels. The most recent common ancestral states of 15 characters diagnosed various lineages recovered from prior studies, some with no prior morphological support. Relatively high frequencies of state change occur in the eastern Asian clade Gaultheria series Gymnobotrys + Diplycosia, the American clade G. subsection Dasyphyta p.p., the core East Asian clade and the Australia/New Zealand clade. The characters with the highest frequencies of state change are the outer stomatal ledge ornamentation type, the stomatal apparatus level, stomatal density and area, and the type of abaxial trichomes. These character state change patterns may provide insight into the ecological adaptions of Gaultherieae during their evolutionary history. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 178 , 686–710.  相似文献   

2.
The phylogenetic relationships of the genera in the geometrid tribe Scopulini (Lepidoptera: Sterrhinae) were examined using 141 characters of adult morphology and ecology. The study material included 92 species, representing all previously recognized genera and covering the morphological variation and full geographical range of the tribe. The cladistic analysis resulted in 20 equally parsimonious trees and a strict consensus cladogram based on these was well resolved. A majority of the recovered synapomorphic characters have been used previously in the taxonomy of the tribe. However, many novel characters were found in the sclerotized structures of the thorax. Many previously recognized genera were found to be nonmonophyletic and based on the present revised, synapomorphy-based classification, the number of recovered genera is reduced considerably. Twenty new generic synonyms and 90 new or revived species combinations are proposed. Seven genera are considered valid, with the large genus Scopula Schrank including over 85% of all species in the tribe. The taxonomic history of the tribe is reviewed and the problems of earlier classifications are discussed. A key to the genera is presented, although an informal diagnosis is preferred. All recognized genera are illustrated and a revised world checklist of the Scopulini is presented.  © 2005 The Linnean Society of London, Zoological Journal of the Linnean Society , 2005, 143 , 473−530.  相似文献   

3.
Although bumblebees have received a lot of attention, some taxonomic problems have persisted for many years. One particularly obdurate case has been the species of the subgenus Subterraneobombus. We revise the bees of this subgenus by integrating evidence from both morphology and, for a 5% subsample, from DNA (cytochrome c oxidase subunit 1, CO1) barcodes from pinned museum specimens. We apply a reciprocal illumination procedure: (1) taxa recognized previously from morphology are used to stratify samples for DNA subsampling; (2) DNA barcodes from these subsamples are used to recognize groups of phylogenetically related specimens; and (3) for these groups, we re‐examine morphological characters in order to recognize and diagnose species. A total of 3854 specimens from 1535 samples from across the geographic range of the subgenus throughout the Holarctic and northern Oriental regions are identified to 11 species. This includes one species newly recognized from Mongolia, Bombus mongolensis Williams sp. nov. Taxon concepts are modified substantially for four species, seven lectotypes are designated, and four new synonyms are recognized. The prevailing usage of Bombus distinguendus is maintained as valid by designating Bombus elegans as a nomen oblitum and designating B. distinguendus as a nomen protectum. Identification keys and colour‐pattern diagrams are provided, and geographic distributions, elevational ranges, and phenological activity periods are described to characterize the species. An estimate of the biogeographic history is reconstructed with dispersal–vicariance analysis. In this study, DNA barcode data have been a cost‐effective source of additional characters for diagnosing groups of specimens. The barcode data contributed directly to recognizing the one new species, of which females remain difficult to identify from morphology alone. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 813–862.  相似文献   

4.
Leaf epidermal features are important taxonomic features in Quercus. We studied leaf epidermal features of 91 species and one forma of Quercus subgenus Cyclobalanopsis using light and scanning electron microscopy. Trichome terminology in oaks was assessed and clarified, aiming to score the epidermal features accurately for genus‐wide comparison. Nine trichome types, anomocytic and cyclocytic stomatal apparatus, smooth layer and platelet epicuticular wax flakes, and two trichome base types were found in subgenus Cyclobalanopsis. The epidermal features revealed three main groups in subgenus Cyclobalanopsis. The epidermal features of Quercus s.l. were uniform, supporting recognition of Cyclobalanopsis as a subgenus of Quercus rather than as a separate genus. Most leaf epidermal features show a mosaic pattern, although their numerous variations offered valuable resources for species identification. The leaf epidermal features that can be used for identification of Quercus leaves are also discussed and summarized. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 176 , 224–260.  相似文献   

5.
Skinks of the genus Sphenomorphus are the most diverse clade of squamates in the Philippine Archipelago. Morphological examination of these species has defined six phenotypic groups that are commonly used in characterizations of taxonomic hypotheses. We used a molecular phylogeny based on four mitochondrial and two nuclear genes to assess the group's biogeographical history in the archipelago and examine the phylogenetic validity of the currently recognized Philippine species groups. We re‐examined traditional characters used to define species groups and used multivariate statistics to quantitatively evaluate group structure in morphometric space. Clustering analyses of phenotypic similarity indicate that some (but not all) members of previously defined species groups are phenotypically most similar to other members of the same group. However, when species group membership was mapped on our partitioned Bayesian phylogenetic hypothesis, only one species group corresponds to a clade; all other species group arrangements are strongly rejected by our phylogeny. Our results demonstrate that (1) previously recognized species group relationships were misled by phenotypic convergence; (2) Sphenomorphus is widely paraphyletic; and (3) multiple lineages have independently invaded the Philippines. Based on this new perspective on the phylogenetic relationships of Philippine Sphenomorphus, we revise the archipelago's diverse assemblage of species at the generic level, and resurrect and/or expand four previously recognized genera, and describe two new genera to accommodate the diversity of Philippine skinks of the Sphenomorphus group. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 1217–1243.  相似文献   

6.
The Aloysia gratissima complex is a group of 22 accepted, specific and infraspecific taxa, the boundaries of which are controversial. Various different authors have chosen different characters as criteria for delimiting taxa in this complex, which has been reflected in the variable number of accepted species. To resolve the taxonomy of this group, a modified population aggregation analysis, based on the phylogenetic species concept, was employed. As a result, the Aloysia gratissima complex is here circumscribed as compromising only four species, A. decipiens, A. gratissima s.s., A. oblanceolata and A. schulziana. These species are sustained by a different combination of four characters, of the 16 qualitative attributes analysed. A new approach based on cluster analysis is proposed here delimiting varieties. As a consequence two varieties, supported by significant differences in quantitative characters, are recognized here: A. gratissima var. gratissima and A. gratissima var. sellowii. A complete taxonomic revision of the accepted taxa is presented and six new synonyms are proposed. A key, illustrations and geographical distribution maps are included. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2016, 180 , 193–212.  相似文献   

7.
The anatomy and morphology of leaves in Carex have the potential to be taxonomically useful. However, studies on the variability of leaf characteristics in the genus are sparse. Researchers therefore risk using leaf anatomical characters without the knowledge of whether they are consistent in a species. We examined 22 qualitative and seven quantitative leaf anatomy characters from transverse leaf sections to test their consistency across 11 Carex spp. The characters were clearly described and primarily microscopic. Some characters were found to exhibit high levels of intraspecific variation, whereas other characters exhibited high levels of consistency in a species, including the shape of the leaf section, the density of papillae and the size of epidermal cells. Caution must be applied when choosing leaf anatomy to delimit taxa because of the intraspecific variability found in some characters, but sufficient numbers of invariant characters exist to provide useful taxonomic separation. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 172 , 371–384.  相似文献   

8.
Leaf morphology and anatomy of Camellia section Camellia (Theaceae)   总被引:1,自引:0,他引:1  
The delimitations of species in Camellia section Camellia have been disputed for many years, resulting from uncertain relationships among species. Leaf morphological and anatomical characters for 54 species and three varieties in this section were investigated to reveal the relationships. Principal component analysis and cluster analysis were conducted using the transformed data for quantitative and qualitative characters from leaf morphology and anatomy. Combining the results of statistical analysis with comparative leaf characters of morphology and anatomy, we discussed the taxonomic treatment of section Camellia by Chang compared with that of Ming and we conclude that section Camellia consists of c. 50 species. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 456–476.  相似文献   

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A phylogenetic reconstruction of the Neotropical electric fish genus Hypopygus based on 47 parsimony‐informative morphological characters is presented. A series of synapomorphies support the hypothesis of monophyly of Hypopygus, and partially resolve species‐level relationships within the genus. Hypopygus species are recognized here as miniaturized fishes based on two criteria; first, a derived condition of diminutive body size, and; second, the presence of a suite of reductive morphological characters, including partial or total losses, simplifications, and reductions of the anal‐fin rays, scales, cranial bones, and laterosensory canal system. Reductive characters associated with miniaturization comprise 45% of the total number of characters in the phylogenetic reconstruction of the genus. Miniaturization and reductive morphological evolution in Hypopygus are discussed here in the phylogenetic context. A taxonomic revision of Hypopygus is presented, in which five new species are described, two species previously assigned to the genus are redescribed, and a single known species of Stegostenopos is redescribed and included in Hypopygus as a junior synonym. Distribution maps and a key for all eight valid species of Hypopygus are provided, based on the examination of 5014 catalogued museum specimens. © 2011 The Linnean Society of London, Zoological Journal of the Linnean Society, 2011, 163 , 1096–1156.  相似文献   

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中国凤仙花科植物叶表皮特征及其分类学意义   总被引:1,自引:0,他引:1  
利用光学显微镜观察凤仙花科106份样本材料、36种代表植物的叶表皮微形态特征。结果表明:该科植物叶表皮微形态特征种内稳定,对于种间及属间关系的界定具有重要的分类学价值。上表皮细胞的形状及垂周壁的式样种间差异明显,各分类群间有明显的界限,是种间界定的重要依据,因此上表皮微形态特征具有重要的的分类学价值,基于上表皮的微形态特征将研究的36种代表植物划分为5个类型。下表皮的微形态特征虽更为多样,种间差异显著,可用于种间界定,但对于属下划分难以提供有价值的性状。该科植物叶表皮微形态特征与宏观形态特征的相关性较弱,与地理分布格局的相关性较强,关系更为密切。同一地理分布区域内的种类宏观形态特征虽然差别明显,但叶表皮微形态特征却表现出较强的一致性,这似乎也反映了叶表皮微形态这一性状受环境饰变的影响比较明显。综上所述,叶表皮微形态特征可为凤仙花科的系统发育,尤其是凤仙花属种间界定提供有价值的分类学佐证  相似文献   

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The taxonomy of the amphi‐Atlantic tree genus Carapa (Meliaceae) has long been controversial. Of the three species currently recognized in the genus, two are known to present substantial morphological variation that has been used in the past to distinguish several taxa, most of which are currently placed in synonymy. Here, a combination of field observations, univariate analyses of leaf, floral and seed characters and principal coordinate analyses of floral characters in the context of a molecular phylogenetic analysis was used to investigate the patterns of variation and delimit morphological species anew in the genus. These results support the recognition of 27 species in Carapa, of which 16 are previously described and 11 are new. In general, phylogenetically related species occurred in the same geographical area, but were morphologically distinct. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 165 , 186–221.  相似文献   

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The taxonomy and systematics of European house spiders, currently constituting the ill‐defined Tegenaria?Malthonica complex (including Aterigena) in the family Agelenidae, are revised. In Europe four monophyletic genera and 81 species are defined. One genus, Eratigena gen. nov. , and seven species are described as new; at species level 17 new synonyms and 20 new combinations are proposed, and the original combination of 14 species is reinstated. Five species could not be placed (incertae sedis) because of insufficient material and one taxon is regarded as ‘nomen dubium’. On the basis of a detailed morphological assessment, 88 characters were chosen for a cladistic analysis. Phylogenetically informative characters include mostly spination patterns as well as spinneret and genital structures. In addition to morphology, three gene sections [cytochrome c oxidase subunit 1 (CO1), nicotinamide adenine dinucleotide dehydrogenase subunit 1 (NADH1) 28S] were analysed. Morphological and molecular analyses were performed individually and in combination applying maximum parsimony and Bayesian tree search methods. In all resulting trees Malthonica and Tegenaria in their present composition are either polyphyletic or paraphyletic. Consequently, we redefined the two genera and erected a new genus, Eratigena gen. nov. Identification keys are provided for the European agelenid genera as well as for the European species of Tegenaria and Eratigena gen. nov. The genera and most of the constituent species are described and illustrated. The new classification has also been applied to some extra European members of the Tegenaria‐Malthonica complex resulting in additional three new synonyms, seven reversals to the original combination, and four new combinations. © 2013 The Linnean Society of London  相似文献   

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18.
Although taxonomic studies indicate that approximately one‐third of the genera of Polygalaceae have nodal glands, few anatomical data are available on the structure and ontogeny of these secretory organs. We studied the as yet unknown origin, structure and function of such glands in Polygala laureola. During field observations, we detected glucose in the secretion using Glicofita Plus® and visitors were recorded. Vegetative shoot apices and nodal glands were examined using light microscopy and scanning electron microscopy. The presence of glucose in the secretion allowed us to identify these nodal glands as extranuptial nectaries. Secretory cells occupy a medullary position and are surrounded by phloem. Vascular bundles are concentric, and xylem is only observed at the basal region of the nectary. Nectar is released during the daytime through a pore at the top of the nectary. A stipular origin was confirmed by the fact that the procambial strand is connected to the leaf trace, opposite the leaf gap. The occurrence of stipular extranuptial nectaries in a nodal position is new to Polygala. © 2011 The Linnean Society of London, Botanical Journal of the Linnean Society, 2011, 166 , 40–50.  相似文献   

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The classification of the genera of the widely distributed Old World tribe Pseudoterpnini is reviewed and 34 genera are recognized. Two new generic synonyms ( Sterictopsis Warren and Oxyphanes Turner as synonyms of Rhuma Walker), and 21 new or reinstated combinations are established. Representative moths of all the genera are illustrated in colour (upper side and underside), and genitalia of all genera are illustrated in monochrome (162 figures). All the known species and subspecies of Pseudoterpnini are listed (321), together with their synonyms. The Pseudoterpnini and their characters are assessed, and many genera are newly assigned to the tribe.  © 2007 Natural History Museum, London. Journal compilation © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 150 , 343–412.  相似文献   

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