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1.
A tropical African group of species commonly included in the genus Satureja is revised and moved to the genus Clinopodium . Satureja abyssinica (Benth.) Briq. ssp. abyssinica and ssp. condensata (Hedberg) Seybold, S. paradoxa (Vatke) Engl. ex Seybold, S. robusta (Hook.f) Brenan and S. vernayana Brenan should be known under the following names: Clinopodium abyssinicum (Hochst. ex Benth.) Kuntze var. abyssinicum and C. abyssinicum var. condensatum (Hedberg) Ryding, C. paradoxum (Vatke) Ryding, C. robustum (Hook.f) Ryding and C. vernayanum (Brenan) Ryding, respectively. Satureja cacondensis (G. Taylor) Brenan, S. masukuensis (Baker) Eyles and S. myriantha (Baker) Brenan, including its varieties, are amalgamated and should be known by the name Clinopodium myrianthum (Baker) Ryding.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 391–408.  相似文献   

2.
The genus Killickia is described to accommodate the South African endemic species formerly placed in Micromeria sect. Hesperothymus . Morphological data, as well as results from unpublished phylogenetic studies support its separation from the genera Micromeria and Clinopodium . A new species Killickia lutea Bräuchler is described and three new combinations are made. Killickia is characterised as comprising solitary- or few-flowered cymes, a campanulate to subcampanulate (obconical) calyx with similar teeth, a corolla tube with two pubescent ridges and nutlets with scattered minute hairs. A thickened marginal vein in the leaves as typical for Micromeria is absent. As currently understood all species are restricted to the Drakensberg mountains and KwaZulu-Natal Midlands in eastern South Africa. A key to the species, brief notes on anatomy and ecology are provided.  © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society , 2008, 157 , 575–586.  相似文献   

3.
Approximately 1.7 kbp of mitochondrial DNA were sequenced from 29 individuals assignable to 11 Uromastyx species or subspecies and two other agamids. U. ocellata and U. ornata had an insertion between the glutamine and isoleucine tRNA genes, which could be folded into a stable stem-and-loop structure, and the insertion for U. ornata additionally retained a sequence similar to the glutamine tRNA gene. This corroborates the role of tandem duplication in reshaping mitochondrial gene arrangements, and supports the idea that the origin of light-strand replication could be relocated within mitochondrial genomes. Molecular phylogeny from different tree-building methods consistently placed African and Arabian taxa in mutually monophyletic groups, excluding U. hardwickii inhabiting India and Pakistan. Unlike previous studies based on morphology , U. macfadyeni did not cluster with morphologically similar Arabian taxa, suggesting convergent evolution to be responsible for the morphological similarities. Divergence times estimated among the Uromastyx taxa, together with geological and palaeontological evidence, suggest that the Uromastyx agamids originated from Central Asia during the Eocene and colonized Africa after its connection with Eurasia in the early Miocene. Their radiation may have been facilitated by repeated aridification of North Africa since the middle Miocene, and geological events such as the expansion of the Red Sea and the East African Rift Valley.  © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 247–260.  相似文献   

4.
Cluster analysis and principal coordinates analysis were used to investigate phenetic variation in Cineraria deltoidea , a species that ranges from near sea level in KwaZulu-Natal, South Africa, to 4300 m a.s.l. on the mountains of East Africa and Ethiopia. Earlier taxonomic revisions reduced nine previously recognized species to synonyms of C. deltoidea . Two closely related species, C. decipiens and C. atriplicifolia , were also included in the analyses. Thirty-six morphological characters were examined on 111 specimens. Phenograms and scattergrams show partial clusters of specimens of C. deltoidea from individual mountains or geographical regions, but no groups are sufficiently distinct to warrant formal recognition at any rank. The East African specimens from 3000 m a.s.l. and higher tend to cluster together. Growth at high altitude in East Africa is correlated with fewer, larger capitula on longer peduncles, and an absence of a cobwebby indumentum comprising long, narrow-based trichomes. Cineraria deltoidea is thus a highly variable species with geographical and clinal variation evident throughout its range. Cineraria atriplicifolia and C. decipiens are maintained as distinct species, distinguished from C. deltoidea by their growth form, life span and auricle shape.  © 2007 University of the Witwatersrand, Johannesburg. Journal compilation © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 497–521.  相似文献   

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The lectotype for Euphrasia hirtella var. ramosa is selected. This taxon and E. hirtella var. karoiana are compared with E. amurensis and confirmed as synonyms, corroborating Juzepcuk (1955 ).  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 215–223.  相似文献   

7.
Two new taxa in Stipa L. Sect. Leiostipa Dumort., S. alba and S. letournexii ssp. ignea , are described from southern Tunisia (northern Africa). In addition, the S. letournexii complex is reviewed and a new combination, S. letournexii ssp. tunetana (H.Scholz) F.M. Vázquez, is presented.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 439–444.  相似文献   

8.
East Africa has a reduced mangrove crab species richness when compared to Asian mangroves. To date, only one species of Perisesarma de Man, 1895 has been reported in East Africa, despite more than 30 years of mangrove research in this region. Based on morphology, colour, mtDNA and behaviour, we describe a new species of Perisesarma from Kenya, P. samawati sp. nov. Surprisingly, when comparing molecular data from other species within this genus, P. samawati sp. nov. and the sympatric P. guttatum (A. Milne Edwards, 1869) are not sister species. Some aspects of the ecology of P. guttatum and P. samawati sp. nov. are compared and the differences discussed. Additionally, we compare P. samawati sp. nov. with the ecological literature of a possible sister species P. eumolpe de Man, 1895 from Malaysian mangroves. Our findings suggest that the new species is an ecologically important species in East African mangroves.  © 2004 The Linnean Society of London, Zoological Journal of the Linnean Society , 2004, 141 , 435–445.  相似文献   

9.
The pulmonate snails of the genus Biomphalaria are widely distributed in the tropics, and they are intermediate hosts of the digenean trematode Schistosoma mansoni that causes intestinal schistosomiasis in humans. Recent molecular evidence suggests that Biomphalaria originated in South America, and following a recent transatlantic migration colonized Africa, where it radiated into the currently recognized 12 species. In the present study we further investigate the internal phylogenetic relationships of African Biomphalaria with emphasis on the dispersal and speciation on the continent, especially in the Great Lakes in East Africa. Our results, based on 16S ribosomal DNA, cytochrome oxidase subunit I (COI), and ribosomal internal transcribed spacer I (ITS1), support the monophyly of an African clade with two separate lineages ( Biomphalaria pfeifferi / Biomphalaria camerunensis and the Nilotic species complex/ Biomphalaria angulosa ). Following the initial colonization of Africa, Biomphalaria spread towards the east where a later radiation occurred in the Lake Victoria basin and the Albertine Rift Valley Lakes. With further dispersal along the River Nile, additional speciation took place giving origin to the North-east African species Biomphalaria alexandrina . Our results present almost no support of the species groups of Mandahl-Barth (except for the pfeifferi group), which is in accordance with other molecular appraisals. Our results suggest that Biomphalaria stanleyi , which is endemic to Lake Albert, is not an ecophenotype of the continental B. pfeifferi as previously suggested by other molecular studies. B. angulosa is sequenced for the first time and it is inferred to have an important phylogenetic position as sister group to the Albertine Rift/Lake Victoria basin radiation.  © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 151 , 337–349.  相似文献   

10.
Borassus akeassii Bayton, Ouédraogo & Guinko sp. nov. (Arecaceae) is described as a new species from western Burkina Faso in West Africa. It has been confused with the widely distributed African species B. aethiopum and more recently with the Asian B. flabellifer . However, it is distinguished by its glaucous, green leaves with weakly armed petioles and a characteristic pattern of lamina venation. The fruits have a pointed apex and are greenish when ripe, and the flowers of the pistillate inflorescence are arranged in three spirals. The pollen has a reticulate tectum and distinctive ornamentation. The distribution of B. akeassii is discussed and the status of the varieties of Borassus aethiopum (var. bagamojensis and var. senegalensis ) is examined.  © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society , 2006, 150 , 419–427.  相似文献   

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The Apteranthes europaea complex (Apocynaceae–Asclepiadoideae–Ceropegieae–Stapeliinae) distributed from Morocco/southern Spain along the North African coast of the Mediterranean Sea up to Sinai, Negev and southern Jordan is studied with emphasis on stem and flower morphology by SEM, chromosome sizes and flavonoid compounds. Apteranthes europaea was found to be rich in rather uncommon flavone glycosides. Of these, luteolin 4'-neohesperidoside represents the major flavonoid of all samples; luteolin-3'- O -(6'- O -sinapoylglucoside)-4'- O -neohesperidoside and luteolin-3'- O -(6'- O -feruloylglucoside)-4'- O -neohesperidoside are reported here for the first time. Flavonol glycosides also occur, but in much smaller quantities. The different flower morphs, variation in stem and corolla epidermal structures, slight variations in the length of the 2 n  = 22 chromosomes and in quantitative flavonoid composition are taxonomically best reflected by subdividing the complex into a western var. europaea (Europe and Africa) and an eastern var. judaica (Sinai, Arabia).  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 149 , 419–432.  相似文献   

13.
Evidence from the chloroplast trn T-L spacer, trn L intron and trn L-F spacer shows the subtribe Glossonematinae of the tribe Asclepiadeae, hitherto composed of the Arabian and North African genera Glossonema , Odontanthera and Solenostemma , not to be monophyletic. While the affinities of Solenostemma cannot be determined with certainty at present, molecular, karyological and morphological evidence suggests that Glossonema and Odontanthera are closely allied to Pentarrhinum , an African genus of five species, belonging to the Cynanchinae.  © 2002 The Linnean Society of London, Botanical Journal of the Linnean Society , 2002, 139 , 145–158.  相似文献   

14.
The six-eyed pholcid spiders of East Africa are revised. A new genus is recognized, Buitinga n. gen ., with 17 new species and three species transferred from Spermophora Hentz. The new genus is characterized by the presence of a scape on the epigynum. This scape may be straight or tightly curled up at rest, and is usually highly expandable. Seven additional African and Comoran species are newly described and tentatively assigned to Spermophora . A data matrix with 60 characters and 77 taxa (including 20 East African species and 25 additional Spermophora and ' Spermophora -like' species) is analysed cladistically. Buitinga is closer to the genera Paramicromerys Millot (endemic in Madagascar) and Spermophorides Wunderlich (Mediterranean and Canary Islands) as well as to several African and Comoran species tentatively assigned to Spermophora than to the type species of Spermophora . It is argued that current estimates of species numbers may be inaccurate and that pholcids may turn out to be one of the most diverse spider families.  © 2003 The Linnean Society of London. Zoological Journal of the Linnean Society, 2003, 137, 555−619  相似文献   

15.
The Turkish Crataegus taxa were investigated using morphological, palynological, and anatomical characters. A new series ( Crataegus Section Crataegus Series Peshmenia ), two new species ( Crataegus peshmenii and Crataegus christensenii ), and one variety ( Crataegus rhipidophylla var. kutahyaensis ) are described. Furthermore, Crataegus  ×  browicziana has been assigned to Crataegus rhipidophylla with a new status. Illustrations of the described taxa and their distribution map are also given. The lectotype for Crataegus yaltirikii is designated here.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 155 , 231–240.  相似文献   

16.
This study clarifies the taxonomic status of Anemone coronaria and segregates the species and A. coronaria infraspecific variants using morphological and morphometric analyses. Principal component analysis of the coronaria group was performed on 25 quantitative and qualitative characters, and morphometric analysis of the A. coronaria infraspecific variants was performed on 21 quantitative and qualitative characters. The results showed that the A. coronaria group clustered into four major groups: A. coronaria L., A. biflora DC, A. bucharica (Regel) Juz.ex Komarov, and a final group including A. eranthioides Regel and A. tschernjaewii Regel. The data on the A. coronaria infraspecific variants clustered into six groups: A. coronaria L. var. coronaria L., var. cyanea Ard., var. albiflora Rouy & Fouc., var. parviflora Regel, var. ventreana Ard., and var. rissoana Ard.  © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 417–438.  相似文献   

17.
The lesser Egyptian jerboa Jaculus jaculus is a desert dwelling rodent that inhabits a broad Arabian–Saharan arid zone. Recently, two distant sympatric lineages were described in North‐West Africa, based on morphometric and molecular data, which may correspond to two cryptic species. In the current study, phylogenetic relationships and phylogeographical structure among those lineages and geographical populations from North Africa and the Middle East were investigated. The phylogeographical patterns and genetic diversity of the cytochrome b gene (1110 bp) were addressed on 111 jerboas from 41 localities. We found that the variation in Africa is partitioned into two divergent mitochondrial clades (10.5% divergence relating to 1.65–4.92 Mya) that corresponds to the two cryptic species: J. jaculus and J. deserti. Diversifications within those cryptic species/clades were dated to 0.23–1.13 Mya, suggesting that the Middle Pleistocene climatic change and its environmental consequences affected the evolutionary history of African jerboas. The third distant clade detected, found in the Middle East region, most likely represents a distinct evolutionary unit, independent of the two African lineages. © 2012 The Linnean Society of London, Biological Journal of the Linnean Society, 2012, ??, ??–??.  相似文献   

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The present study clarified the taxonomy, phylogeny and historical demography of semicommensal Nile rats ( Arvicanthis ) from the Nile Valley in Sudan. Nile rats are important crop pests and zoonotic disease reservoirs and are closely associated with agricultural settlements in the Nile Valley. Phylogenetic analysis of the complete cytochrome b gene (1140 bp) of 23 individuals from six localities in Sudan (from two previously recognized species, Arvicanthis niloticus and Arvicanthis testicularis ), supported the existence of only a single species, A. niloticus , from the Nile Valley. Historical demography of the Sudanese Nile Valley population inferred from mismatch coefficients indicated that an exponential population expansion event occurred approximately 144 000–288 000 years ago, corresponding in time with early human expansion and colonization from Africa to the Middle East, Europe, and the world. The inferred high level of gene flow and large size of Sudanese Nile populations of A. niloticus is consistent with historically recent (300 years ago) exponential human population growth and intense agricultural activity inferred from archaeological and historical evidence. Two African Arvicanthis clades were well supported by the broader phylogenetic analysis: (1) A. niloticus , Arvicanthis abyssinicus and Arvicanthis neumanni and (2) Arvicanthis rufinus and Arvicanthis ansorgei from western Africa. Within the first clade, divergence between lineages of A. niloticus s.s. from west and north-east Africa (8.9%) suggests specific recognition, but sampling of geographically intermediate localities is required. Based on hypothesized palaeodrainage and palaeoclimatic patterns, we propose a simple model for speciation of Arvicanthis in Africa.  © 2008 The Linnean Society of London, Biological Journal of the Linnean Society , 2008, 93 , 641–655.  相似文献   

20.
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