首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The sepiids are characterized by their cuttlebone or sepion, an internal shell resulting from secondary mineralization of a chitinous 'gladius'. The various species are identified using a combination of shell criteria and 'soft-part' characters. Using mitochondrial genes, we established phylogenetic relationships of sepiids including the three accepted genera ( Sepia , Sepiella , Metasepia ) and a species complex of uncertain status ( Doratosepion ). We showed the Sepia genus to be paraphyletic and found no direct correlation between geographical distribution and systematics. We mapped, on the molecular tree, shell characteristics commonly used as reliable diagnostic criteria for taxonomy. Due to the plasticity of the shell, these characters did not appear phylogenetically informative. In an attempt to define systematic categories related to phylogenetic relationships, new clear synapomorphies need to be established for each genus, necessitating a revision of the genus Sepia .  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 139–150.  相似文献   

2.
Species-level phylogeny of the Butterfly tribe Argynnini is established based on 141 characters derived from wing and genitalia morphology of both sexes. The Argynnini can be divided into three subtribes; Yrameina comprising Yramea and Boloria s . l ., Argynnina comprising Prokuekenthaliella , Issoria , Brenthis , and all the 'large fritillary' species joined in the genus Argynnis s . l . and a new subtribe Euptoietina comprising only the genus Euptoieta . The classical genus Issoria s . l . is polyphyletic regarding Yramea and possibly paraphyletic regarding the two Afrotropic species baumanni and hanningtoni ; these two species are tentatively transferred to the old genus/subgenus Prokuekenthaliella . Surprisingly, one Afrotropic species, Issoria smaragdifera is closely related to the East Palaearctic Issoria species. A revised classification of Argynnini is proposed based on the obtained phylogeny. Studies of larval host plants based on the obtained phylogeny suggest that the ancestral Argynnini used Passiflora and Violaceae, but already the ancestor of Yrameina + Argynnina was probably specialized on Violaceae. Whereas the Boloria species have turned to other food plants such as Dryas , Vaccinium and Salix on several occasions, only Brenthis among the Argynnina use other host plants than Viola (mainly Rosaceae). The habit of laying eggs away from the food plant has probably evolved twice within Argynnina.  © 2006 The Linnean Society of London, Biological Journal of the Linnean Society , 2006, 89 , 627–673.  相似文献   

3.
We describe Centrolene bacatum , C. buckleyi , Cochranella posadae , and a new species of Cochranella from Yanayacu Biological Station on the Amazonian slopes of the Ecuadorian Andes. The new species differs from other species in Centrolenidae by a combination of characters, including reduced webbing between Fingers III and IV, and kidneys covered with white peritoneum. We summarize the current generic and infrageneric classification in Centrolenidae and discuss some of its problems. A phylogenetic analysis of morphological and behavioural data shows that the genera Centrolene and Cochranella might not be monophyletic; the genus Hyalinobatrachium and, in particular, the group H. fleischmanni seem to be monophyletic. However, an analysis with many more characters is needed to resolve the relationships of glass frogs.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 489–513.  相似文献   

4.
5.
6.
Chromosome counts are reported of 38 populations representing 24 species of the genus Cousinia from Iran, one of the main centres of speciation of the genus. Sixteen of the counts are new to science. Our results confirm that Cousinia exhibits a complex dysploid series ranging from x  = 13 to x  = 9. One of the basic chromosome numbers, x  = 9, is new for the genus and must be confirmed. Some considerations on the correlation between chromosome numbers and section classification are made.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 411–419.  相似文献   

7.
A distinctive new species of Rubiaceae from Rio Muni, Equatorial Guinea, is described and illustrated. Leptactina rheophytica is the only rheophyte known in the genus. Its diagnostic characters are elucidated, its taxonomic affinities are discussed, and notes on its conservation status are provided.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 109–113.  相似文献   

8.
A distinctive new species of dwarf monocaulous Coffea (Rubiaceae) from Cameroon is described and illustrated. Coffea mapiana is the second dwarf monocaulous known from Cameroon. Its diagnostic characters are elucidated and its taxonomic affinities are discussed; a conservation assessment is provided.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 425–430.  相似文献   

9.
10.
Section Choretropsis genus Phyllanthus (Euphorbiaceae) is formed by plants whose branches are modified into phylloclades. Despite the suitable characteristics of phylloclades within the Phyllanthus genus, the systematics of these species are poorly understood. Morphological data are presented here to allow future revision of this taxonomic group. The section is represented by nine species distributed in South America, eight of them endemic to Brazil. Our taxonomic studies distinguish the species and propose the synonymization of nine varieties of P. klotzschianus and two varieties of P. flagelliformis based on vegetative and reproductive characters. The diversity of branching and the morphology of phylloclades are discussed.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 131–164.  相似文献   

11.
Mantalania longipedunculata De Block & A.P. Davis, a new species of Rubiaceae (Gardenieae) from Île Sainte Marie, Madagascar, is described, illustrated, and compared with the three other species in the genus. An extinction risk assessment is given, using the categories and criteria of the World Conservation Union (IUCN).  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 421–424.  相似文献   

12.
The genus Hexabathynella (Crustacea, Malacostraca, Bathynellacea) is revised in the sense of the phylogenetic systematics and four new species are described from South Africa ( H. monoaethetasca sp. nov. and H. africana sp. nov. ) and America ( H. schrieveri sp. nov. and H. virginiae sp. nov. ). A comparative analysis of all observable outer structures distributed in 18 known and four new species resulted in a re-evaluation of 18 characters and character states. The phylogenetic analysis using the program PAUP yielded one most-parsimonious tree, which suggests the grouping of ( H. decora (( H. halophila  +  H. aotearoae ) + ( H. pauliani ( H. monoaethetasca  + H. africana )))) + ( H. knoepffleri ( H. nicoleiana ( H. hebrica , H. tenera , H. longiappendiculata , H. breviappendiculata , H. nestica ) +  H. virginiae (( H. minuta ( H. valdecasasi + H. otayana )) + ( H. hessleri + H. muliebris ))) +  H. paranaensis ( H. szidati + H. schrieveri )). The tree is 57 steps long and has a consistency index of 0.6140, a retention index of 0.7982 and a rescaled consistency index of 0.4901. The result does not agree with the previous analyses on the genus. In terms of sampling and coding, the characters used in the previous study are critically assessed.  © 2006 The Linnean Society of London, Zoological Journal of the Linnean Society , 2006, 147 , 71–96.  相似文献   

13.
The spider genus Weintrauboa new genus (Araneae, Pimoidae) is described to place two species of pimoids from Japan and adjacent islands that were formerly classified in the linyphiid genus Labulla . Weintrauboa contortipes (Karsch) new comb., the type species, and W. chikunii (Oi) new comb. are redescribed. Parsimony analysis of morphological characters provides robust support for the monophyly of the genus Weintrauboa and corroborates the monophyly of Pimoa , Pimoidae, and the clade Linyphiidae plus Pimoidae. New diagnoses for Pimoa and Pimoidae are provided.  © 2003 The Linnean Society of London, Zoological Journal of the Linnean Society , 2003, 139 , 261–281  相似文献   

14.
Cerdia is a poorly understood genus of minute cushiony plants endemic to Mexico that is traditionally placed in subfamily Paronychioideae, tribe Polycarpeae (Caryophyllaceae). Morphological observations and phylogenetic analysis of ITS DNA sequences were carried out to determine the number of species, heretofore controversial, that constitute the genus as well as its position within Caryophyllaceae. Samples of Cerdia were collected through its entire range of distribution and together with previous specimens were used in morphological analyses. Nineteen terminal taxa were considered in a phylogenetic analysis with representatives of the different lineages in Caryophyllaceae. Results indicated that Cerdia is a monotypic genus, including only one variable species, C .  virescens , but its phylogenetic affinities remain doubtful.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 1–13.  相似文献   

15.
16.
The Malagasy representatives of the large African genus Tricalysia (tribe Coffeeae s.l.) are revised. Three Malagasy species were hitherto recognized in the genus, namely T. cryptocalyx , T. madagascariensis , and T. ovalifolia . In this study, two species, T. boiviniana and T. leucocarpa , are transferred from the genus Hypobathrum and seven new species and two new subspecies are described, raising the species number for Tricalysia to a total of 12. This marked increase in species number is a recurring pattern for many Malagasy genera in systematically poorly known families such as Rubiaceae. All the species are described in detail and illustrated, and a list of exsiccatae and a distribution map are provided. Furthermore, the characters of the Malagasy taxa are compared with those of the continental African species, and their infrageneric status is discussed. With the exception of T. ovalifolia , a member of subgenus Empogona , all Malagasy species belong to subgenus Tricalysia . Because of their unisexual flowers, these species cannot be accommodated within one of the four existing sections in subgenus Tricalysia . A new section, Androgyne , is therefore recognized.  © 2007 National Botanic Garden of Belgium. Journal compilation © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 83–126.  相似文献   

17.
18.
Klasea , traditionally treated as a section in Serratula , is now widely accepted at the generic level. A classification of the genus is presented here, accommodating the 46 species in ten sections based on nuclear ribosomal DNA external and internal transcribed spacer sequence data and morphology. New combinations for five species and ten subspecies are published, and a new hybrid species is described. The genus ranges from the Iberian Peninsula and north Africa through southern and eastern Europe, west and central Asia to the Himalayas, and the Far East of Russia and China. The ancestral area is in west Asia, most probably eastern Anatolia and northern and western Iran. In this region, representatives of all sections are present. The largest section Klasea diversified most likely in the mountains of central Asia. A key to all Klasea species is provided.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 152 , 435–464.  相似文献   

19.
Comparative morphology of the leaf epidermis in Schisandra (Schisandraceae)   总被引:9,自引:0,他引:9  
The leaf epidermis of 127 samples representing ten species within Schisandra Michaux. and one species of the related genus, Kadsura Kaempf. ex Juss., was investigated using light and scanning electron microscopy. Many characters of the leaf epidermis in Schisandra , such as pattern of epidermal cells, type of stomata, shape of guard cell pairs and cuticular ornamentation, are usually constant within species and thus make good characters for studying the relationship between and within genera. A new character, rim number, of the outer stomatal rim in the genus is introduced. It is shown that double outer stomatal rims occur only in evergreen Schisandra species, whereas a single rim occurs in deciduous species. This character supports the classification of Schisandra into two subgenera based on habit and androecial organs. This classification is also supported by additional morphological and molecular taxonomic characters. Kadsura coccinea (Lem.) Smith A. C. is the most primitive taxon in the related genus Kadsura . The outer stomatal rim of this species also has double rims. Combined with morphological and molecular evidence, this suggests that Schisandra and Kadsura are closely related and may share a recent common ancestor.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 39–56.  相似文献   

20.
The systematics of the Asplenium seelosii complex has been debated for a long time. This complex includes strictly rupicolous plants that live on limestone cliffs mainly in the mountains of south-west Europe: the Alps, the Pyrenees, and several mountain ranges of the eastern Iberian Peninsula. The disjunct distribution of its populations and several morphological characters, i.e. leaf indumentum and the structure of the perispore, have been used to distinguish two species and up to four subspecies. The goal of this study was to determine whether the characters of the gametophytic generation and young sporophytes can contribute to the recognition of the proposed taxa. The analysis of all of these characters together differentiated two groups that correspond to the established species, A. seelosii and A. celtibericum , but not enough differences were found to separate the subspecies in each of them.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 151 , 375–386.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号