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1.
It has been suggested that southern Africa is the origin of the predominantly herbaceous Apiaceae subfamily Apioideae and that the woody habit is plesiomorphic. We expand previous molecular phylogenetic analyses of the family by considering all but three of the approximately 38 genera native to southern Africa, including all genera whose members, save one, have a woody habit. Representatives of five other genera are included because they may be closely related to these southern African taxa. Chloroplast DNA rps16 intron and/or nuclear rDNA ITS sequences for 154 accessions are analyzed using maximum parsimony, Bayesian, and maximum likelihood methods. Within Apioideae, two major clades hitherto unrecognized in the subfamily are inferred. The monogeneric Lichtensteinia clade is sister group to all other members of the subfamily, whereas the Annesorhiza clade (Annesorhiza, Chamarea, and Itasina) plus Molopospermum (and Astydamia in the ITS trees) are the successive sister group to all Apioideae except Lichtensteinia. Tribe Heteromorpheae is expanded to include Pseudocarum, "Oreofraga" ined., and five genera endemic to Madagascar. The southern African origin of subfamily Apioideae is corroborated (with subsequent migration northward into Eurasia along two dispersal routes), and the positions of the herbaceous Lichtensteinia and Annesorhiza clades within the subfamily suggest, surprisingly, that its ancestor was herbaceous, not woody.  相似文献   

2.
The tribe Psoraleeae (Leguminosae subfamily Papilionoideae) comprises 185 species in nine genera that have a nearly worldwide distribution, occurring predominantly in Mediterranean regions. About 60% of the species belong to the genera, Otholobium C.H.Stirt. and Psoralea L., which have a centre of diversity in the Cape Floristic Region of South Africa. Since previous molecular studies have sampled only a few species of the tribe from this region, this study sought to determine the phylogenetic position of the southern African genera and to test whether they are monophyletic. Phylogenetic relationships were reconstructed using DNA sequence data (trnL-F, rpoB-trnC and ITS) and seven morphological characters, which diagnose the two southern African genera. The data were analysed using the parsimony method. There was strong support for the Psoraleeae as a clade, but most of the nodes within the large genera were poorly supported. The southern African species of Psoralea and Otholobium together formed a strongly supported clade. This clade was sister to the genus Hoita Rydb., but without support. However, the Psoralea species were nested within the southern African Otholobium. Additionally, some South American species that are currently recognised as Otholobium were resolved in a clade distinct from the southern African species, making Otholobium polyphyletic. Morphological characters that separate Otholobium and Psoralea are discussed. Finally, the southern African genera as currently circumscribed are not monophyletic. However, further investigations using more informative DNA loci are required to validate this observation. Furthermore, the taxonomic placement of the South American species needs to be reviewed.  相似文献   

3.
鹂雀(Linurgus olivaceus)是非洲热带森林中一种独特的鸣禽,为鹂雀属(Linurgus)的惟一物种。在已有的研究中,通过对鹂雀和雀形目现存鸟类中每个科及亚科至少一个物种的线粒体DNA序列测定,分析了鹂雀与其它现存雀形目鸟类的系统发生关系;在遗传上,对鹂雀与金丝雀、金翅雀及燕雀亚科其它鸟类亦有比较研究。本研究共使用了燕雀亚科83种鸟类,重点对该亚科的系统发生进行了修订。使用贝叶斯法构建了系统发生树,结果表明:鹂雀属于燕雀亚科,系统发生树中聚在金翅雀族(Carduelini),与金丝雀属(Serinus)、金翅雀属(Carduelis)及交嘴雀属(Loxia)的种类形成一组;在系统发生中,鹂雀可能是一个基部物种,它同金丝雀属和金翅雀属鸟类一同进化并分歧出来。在本研究中未能涉及的一些已灭绝种类,可能与鹂雀有着较近的遗传学关系。另一方面,研究也表明锡嘴雀(Coccotharustes coccothraustes)肯定包括在欧亚蜡嘴雀(蜡嘴雀属Eophona和拟蜡嘴雀属Mycerobas)中,美洲的朱雀(Carpodacus)可能是从亚洲种类分歧出来并经过进化辐射形成。  相似文献   

4.
An opecoelid, Bartoliella pritchardae n. g., n. sp., is described from the intestine of Epinephelides armatus from Western Australia. The new genus has been assigned to the subfamily Opecoelininae Gibson & Bray, 1984, bringing the number of genera in the subfamily to two. Although the new genus is similar to Opecoelina Manter, 1934 morphologically, the pedunculate ventral sucker and complete absence of a cirrus-sac necessitate the erection of a new genus. A formal re-definition of the subfamily is given, based on the diagnoses of the genera Opecoelina and Bartoliella n. g.  相似文献   

5.
The Dufour gland epithelium in Aenictus has a crenellate appearance, a condition previously found only in the primarily African genus Dorylus . This character, taken alone, strongly suggests that these two genera share a common ancestry, as is presently reflected in their placement in the subfamily Dorylinae, and that an independent, convergent origin for them, as has been proposed in the triphyletic hypothesis for army ant evolution, is incorrect.  相似文献   

6.
Abstract. The rare Neotropical ant subfamily Leptanilloidinae is revised and its internal phylogeny and biogeography discussed. A new genus, Asphinctanilloides gen.n., including three new species, A. amazona, A. anae and A. manauara, and three new species of Leptanilloides , L. improvisa, L. legionaria and L. sculpturata are described. The only previously known species of the subfamily, L . biconstricta Mann (1923) , is redescribed, and the larva of L. legionaria sp.n. is described. Keys to the genera and the species, and a phylogeny of the group are provided. Emphasis has been placed on the study of abdominal and sting characters.  相似文献   

7.
Legume subfamily Caesalpinioideae accommodates approximately 2250 species in 171 genera which traditionally are placed in four tribes: Caesalpinieae, Cassieae, Cercideae and Detarieae. The monophyletic tribe Detarieae includes the Amherstieae subclade which contains about 55 genera. Our knowledge of the relationships among those genera is good in some cases but for many other genera phylogenetic relationships have been unclear. The non-monophyletic nature of at least two amherstioid genera, Cynometra and Hymenostegia has also complicated the picture. During the course of a multi-disciplinary study of Hymenostegia sensu lato, which includes phylogenetic analyses based on matK and trnL data, we have recovered the “Scorodophloeus clade”, an exclusively tropical African clade of four genera which includes the eponymous genus Scorodophloeus, two undescribed generic segregates of Hymenostegia sensu lato, and the previously unsampled rare monospecific genus Micklethwaitia from Mozambique. Zenkerella is suggested as a possible sister genus to the Scorodophloeus clade. A distribution map is presented of the seven species that belong to the Scorodophloeus clade.  相似文献   

8.
Within South African Asteraceae-Anthemideae there is a group of genera containing furanosesquiterpenes rather than the common polyacetylenes. Of these genera, Asaemia (Harv.) Ham. ex Benth. & Hook., Athanasia L., Eumorphia DC., Gymno-pcnfzia Benth., Phymaspermum Less. and Sfilpnophyfon Less. have been investigated morphologically especially with respect to fruit structure. As a result of the investigations Stilpnophyton has been reduced to synonomy under Athanasia L. emend. Källersjö (with 36 spp.) and five species of Athanasia , together with Phaeocephalus S. Moore., are placed in the revived genus Hymenolepis Cass. (with 7 spp.). Brachymerk DC. and four misplaced species of Aihanasia are included in Phymaspermum Less. emend. Källersjö (with 17 spp.). Nine other misplaced species of Athanasia and one Pentzia Thunb. species have been described as a new genus Inulanihera Källersjö (with 10 spp.), a group without furanosesquiterpenes. The two monotypic genera Asaemia and Gymnopentzia , and Eumorphia (with 6 spp.) remain unchanged. The interrelationships of the genera possessing furanosesquiterpenes are shown in a cladogram. There are 25 new combinations in Afhanasia, Znulanthera, Hymenolepis and Phymaspermum .  相似文献   

9.
Abstract. The South African genus Pameridea and its two species are redescribed. The tribe Pamerideini, founded for this genus only, is removed from synonymy with Mirini (subfamily Mirinae) and transferred to Dicyphini (subfamily Bryocorinae), falling as a synonym of the subtribe Dicyphina. The bugs live only on intensely viscid small shrubs of the genus Roridula. This plant genus is the only member of its family but the bug genus is closely related to two widespread tropical dicyphine genera.  相似文献   

10.
A classification of the Ericaceae: subfamilies and tribes   总被引:4,自引:1,他引:3  
The variation shown by 60 characters (morphological, anatomical, embryological, chemical and cytological) is tabulated for the whole of the Ericaceae. The reliability of the characters and the observations on them are discussed, and it is emphasized that many characters are difficult to use because they are rarely restricted to one taxon. Six subfamilies are recognized. Within the Rhododendroideae seven tribes are recognized, the monogeneric Daboecieae being new; Epigaea is transferred to the Rhododendroideae from the Andromedeae and Diplarche from the Diapensiaceae. Calluna is placed in a new monotypic tribe within the Ericoideae. The extended Vaccinioideae includes the Arbutoideae; five tribes are recognized, of which the Enkiantheae and Cassiopeae are new. The Pyroloideae and Monotropoideae are left unchanged: a new subfamily, the Wittsteinioideae, includes the deviant monotypic genus Wittsteinia. A key to subfamilies, and to genera of the Pyroloideae, Rhododendroideae and superior-ovaried Vaccinioideae is given.  相似文献   

11.
An attempt is made to apply cluster analysis to comparison of local faunas in the Northern Hemisphere at the genus level by the example of the subfamily Arctiinae (Lepidoptera, Arctiidae). A total of 200 North African, Eurasian (to New Guinea inclusive), and North American (north of the United Mexican States) local faunas have been considered. It is found that the arctic fauna is clearly detached from the Palearctic and Nearctic faunas, being closer to the former. Therefore, it is not reasonable to recognize the united European-Canadian subprovince of the boreal province according to the tiger moth faunas. The Palearctic tiger moth fauna is characterized by relatively smooth variations within the boreal, subboreal, and western subtropical belts. The boundary between the Palearctic and the Oriental (Indo-Malayan) provinces should be drawn north of the Yangtze catchment area. The most dramatic fauna change at the genus level takes place between North and Northeast China. It is reasonable to recognize a broad transition area between the two zoogeographic provinces in Eastern Asia. On the grounds of the nonuniform tiger moth fauna, the South Chinese-East Himalayan subprovince should be assigned to the Oriental (Indo-Malayan) province rather than the Palearctic, as was repeatedly proposed. The Southwest-Asian fauna (Arabian Peninsula and southern Iran) is transitional between the Palearctic, African, and Oriental ones. Many African genera reach the west and south of the Arabian Peninsula, whereas Oriental and Paleotropical genera reach southern Iran.  相似文献   

12.
Current phylogenetic hypotheses on the African Crocidurinae (Soricidae) are based upon morpho-anatomical, karyological, and allozyme studies. The present study attempts to resolve the interrelationships among African Crocidurinae and their relationships to Eurasian Crocidurinae and to the subfamily Soricinae, on the basis of partial mitochondrial 16s rRNA sequences (549 bp). This is the first molecular study to include all but one of the nine currently recognized African shrew genera. In agreement with current views, two major lineages emerge. The first lineage includes Myosorex and Congosorex and supports the existence of a myosoricine taxon. The second lineage includes the six remaining genera. The genus Sylvisorex appears to be polyphyletic, whereas species of the controversial genus Crocidura are monophyletic. The genus Suncus presumably originated in Africa. The monospecific genera Ruwenzorisorex and Scutisorex and the two representatives of Paracrocidura cluster with species of other genera. Grouping patterns of species from different continents suggest that there have been multiple exchanges between Africa and Eurasia. The time estimates of these exchanges, inferred from two independent fossil-based calibrations of a molecular clock, coincide with the time estimates for migration events in other mammalian taxa.  相似文献   

13.
The plastid coding rbcL and non-coding trnLF regions of 53 of 55 southern African Zygophyllum species were sequenced and used to evaluate the phylogenetic relationships within the southern African representatives of the genus. Published sequences of the same gene regions of Australian, Asian and North African Zygophyllum species were included to assess the relationships of the species from these regions to the southern African species. The addition of Z. stapffii from Namibia, found to be conspecific with Z. orbiculatum from Angola, lead to a greatly resolved tree. The molecular results were largely congruent with a recent sectional classification of the southern African species and supported their subdivision into subgenera Agrophyllum and Zygophyllum. Reconstruction of the character evolution of capsule dehiscence, seed attachment and seed mucilage showed that these characters allowed a division of southern African species into the two subgenera but that this could not be applied to species occurring elsewhere. Other morphological characters were found to vary and unique character combinations, rather than unique characters, were found to be of systematic value in sectional delimitation. The study suggests that repeated radiations from the horn of Africa to southern Africa and Asia and back lead to the present distribution of the taxa in the subfamily Zygophylloideae. Although this study supports some of the recent taxonomic changes in the group, the unresolved relationships between the proposed genera Tetraena and Roepera and those retained as Zygophyllum species suggest that changes to the taxonomy may have been premature.  相似文献   

14.
The genus Crinum L. is the only pantropical genus of the Amaryllidaceae. Phylogenetic and biogeographical analyses of nrDNA ITS and plastid trnL-F sequences for all continental groups of the genus Crinum and related African genera are presented, with the genus Amaryllis used as outgroup. ITS indicates that C. baumii is more closely related to Ammocharis and Cybistetes than to Crinum sensu stricto . Three clades are resolved in Crinum s.s. One unites a monophyletic American group with tropical and North African species. The second includes all southern African species and the Australian endemic C. flaccidum . The third includes monophyletic Madagascar, Australasian and Sino-Himalayan clades, with southern African species. The trnL-F phylogeny resolves an American and an Asian/Madagscar clade, and confirms the relationship of C. flaccidum with species endemic to southern Africa. The salverform, actinomorphic perianths of subg. Crinum appear to have evolved several times in the genus from ancestors with zygomorphic perianths (subg. Codonocrinum ), thus neither subgenus is monophyletic. Biogeographical analyses place the origin of Crinum in southern Africa, as the region is optimized at all ancestral nodes in the tree topology, and in basal interior nodes of all but one of the major clades. The genus underwent three major waves of radiation corresponding to the three main clades resolved in our trees. Two entries into Australia for the genus are indicated, as are separate Sino-Himalayan and Australasian dispersal events.  © 2003 The Linnean Society of London, Botanical Journal of the Linnean Society , 2003, 141 , 349–363.  相似文献   

15.
A new fossil species of crane-fly, Helius botswanensis :Diptera: Tipulidaey is described. The specimen was discovered recently in reliably dated. Cretaceous sediments from Botswana. Ii is extremely well preserved, has a distinctive morphology, and is identified as belonging to the extant genus Helius. The single specimen puts the origin of the subfamily Limoniinae and the genus well into the Cretaceous Period, and provides data on the southern African Cretaceous palaeoenvironment. The conservative nature of a dipteran of such antiquity, assignable to an extant genus which has an association with flowers, has implications for evolutionary theory.  相似文献   

16.
Of the genera within the coralline algal subfamily Melobesioideae, the genera Leptophytum Adey and Phymatolithon Foslie have probably been the most contentious in recent years. In recent publications, the name Leptophytum was used in quotation marks because South African taxa ascribed to this genus had not been formally transferred to another genus or reduced to synonymy. The status and generic disposition of those species (L. acervatum, L. ferox, L. foveatum) have remained unresolved ever since Düwel and Wegeberg (1996) determined from a study of relevant types and other specimens that Leptophytum Adey was a heterotypic synonym of Phymatolithon Foslie. Based on our study of numerous recently collected specimens and of published data on the relevant types, we have concluded that each of the above species previously ascribed to Leptophytum represents a distinct species of Phymatolithon, and that four species (incl. P. repandum) of Phymatolithon are currently known to occur in South Africa.Here we present detailed illustrated accounts of each of the four species, including: new data on male and female/carposporangial conceptacles; ecological and morphological/anatomical comparisons; and a review of the information on the various features used previously to separate Leptophytum and Phymatolithon. Southern African species ascribed to the genus Phymatolithon may be separated from one another in the field by their growth forms, the substrata on which they are generally found, and the colour of living thalli. A key for identifying southern African specimens in the field is included. Our data support the conclusion that the characters upon which Leptophytum is based are unreliable for generic delimitation from Phymatolithon.  相似文献   

17.
Chonodemus gervaisi, n. sp., is described from San Agustín, Colombia. The genus Chonodesmus in many ways provides a link between the three nominal families Cryptodesmidae, Pterodesmidae, and Peridontodesmidae, and it is proposed that the three be combined into a single taxon, Cryptodesmidae, with the other two names retained for subordinate groups. A provisional classification of the family is suggested, including generic synonymy, and the new tribes Lampodesmini, Ophrydes‐mini, Dyakryptini, and Trichopeltini are proposed. The family name Otodesmidae is reduced to subfamily rank, and the name Niponiellidae reduced to tribal status. A key is provided for four West African genera of the subfamily Pterodesminae.  相似文献   

18.
The genus Billburttia is described to include two new species endemic to Madagascar, B. capensoides and B. vaginoides. Both species were tentatively placed within the problematic genus Peucedanum L. (as Peucedanum sp. A and Peucedanum sp. B) based on their dorsally compressed fruits lacking prominent dorsal ribs and with winged marginal ribs. Recently, however, the African members of Peucedanum have been shown to be only distantly related to the type of the genus and have therefore been segregated into six African endemic genera. While the Malagasy species appear superficially similar to members from one of these segregate genera, viz. Notobubon, they differ markedly in their fruit anatomical characters, notably a narrower commissure, six commissural vittae, vascular tissue in the tip of the ribs and sphaerocrystals distributed in and around the epidermis. The latter two characters apparently represent apomorphies for Billburttia. The non-peucedanoid affinity of the genus, as suggested by the fruit anatomical data, was confirmed using ITS and rps16 intron sequences. Both parsimony and Bayesian analyses of these data place Billburttia within the tribe Apieae of subfamily Apioideae and not closely related to either Peucedanum (Selineae) or the African peucedanoid genera (Lefebvrea clade of Tordylieae).  相似文献   

19.
The genus Plectranthus (Lamiaceae) is a significant, prolific and extensively used genus in southern Africa. It plays a dominant role in both horticulture and traditional medicine. Some 12 species are documented for their use in treating ailments by various indigenous peoples of southern Africa. It is a firm favourite in gardens and Plectranthus has been bred to further utilise the remarkable diversity of indigenous South African wildflowers with amenity horticultural potential. Although previously subjected to both horticultural (Van Jaarsveld, 2006) and ethnobotanical (Lukhoba et al., 2006) review, Plectranthus is a genus with economic potential in various sectors, and this article aims to review this potential of southern African species.  相似文献   

20.
The freshwater African catfish family Amphiliidae had been reviewed based on the 73 osteological characters with Diplomystidae, 2 Hypsidoridae, Amblycipitidae, Sisoridae, and Bagridae as out-groups. Because the family position of Leptoglanis (Bagridae/Amphiliidae) is under debate, this genus has been taken as an out-group too. Results of the study indicate that: 1) the Amphiliidae is not a monophyletic group and must now be restricted to the genera Amphilius and Paramphilius; the two subfamilies Amphiliinae and Doumeinae are separated by the sisorids Euchiloglanis (with most of the glyptosternid fishes) and Glyptothorax (with most of the non-glyptosternid fishes); 2) no synapomorphies were found for the subfamily Amphiliinae. 3) The five genera of subfamily Doumeinae constitute a monophyletic group, Andersonia being the sister-group of the four other genera; subfamily Doumeinae + Leptoglanis form the family Doumeidae. The glyptosternids no longer belong to the Sisoridae (family restricted to the non-glyptosternids) and represent the new family Glyptosternidae.  相似文献   

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