Karyotypes of some species of Hyacinthaceae from Ethiopia and Kenya

Karyotypes for 8 different species of Hyacinthaceae from Ethiopia and Kenya are presented. Five represent new chromosome information: Drimia macrocarpa (2n = 20 + 4 B), Ledebouria revoluta (2n = 28), L. somaliensis (2n = 30), L. urceolatu (2n = 20), Ornithogalum grucillimum (2n = 24). A table summing up the present chromosome information from tropical East and North East-Africa are given.     

A revision of the genus Drimia (Hyacinthaceae) in East Africa

The generic delimitation of Drimia and Urginea is discussed with special reference to flower and seed morphology (LM & SEM). The data support the joining of the two into one genus, Drimia. The following taxa are represented in East Africa (Kenya, Tanzania, Uganda): Drimia altissima, D. brachystachys comb, nov., D. calcarata comb, nov., D. congesta, D. elata, D. indica, D. macrocarpa sp. nov., and D. porphyrantha comb. nov.     

Analysis of ribosomal DNA internal transcribed spacer sequences of the Leishmania donovani complex

To understand phylogenetic relationships of species and strains within the Leishmania donovani complex, we have analyzed the ribosomal DNA internal transcribed spacer (ITS) sequences of 27 Leishmania infantum, 2 Leishmania chagasi, 18 L. donovani and 5 Leishmania archibaldi strains of different zymodemes and geographical origin. Eight ITS sequence types were found. All detected sequence variation within ITS1 and ITS2 was based on 12 polymorphic microsatellites. The L. infantum strains from the Mediterranean region, China and L. chagasi from the New World formed a phylogenetic group well separated from the second main group including all strains from East Africa and India. Within the latter group three distinct phylogenetic subgroups could be differentiated: (1) L. donovani (Sudan/Ethiopia, China) + L. archibaldi (Sudan), (2) L. donovani (Sudan/Ethiopia) + L. infantum (Sudan) + L. archibaldi (Sudan/Ethiopia), and (3) L. donovani (Kenya, India). These groups are not consistent with previous species definitions based on isoenzyme analyses, e.g. L. infantum is polyphyletic and L. archibaldi is not supported as a distinct species. Two groups of Indian strains could be differentiated, one of which has an identical sequence type to the strains from Kenya. Three main lineages of strains can thus be differentiated in East Africa: two quite distantly related groups of strains from Sudan/Ethiopia, and a third group including all strains from Kenya, which is more closely related to part of the Indian strains than to any of the Sudanese/Ethiopian groups. The ITS sequence analysis presented here supports the need for revision of the taxonomy of the L. donovani complex.     

The genusPicris (Asteraceae,Lactuceae) in Tropical Africa

Three species of the genusPicris L. are native in Tropical Africa:P. abyssinica Sch. Bip. (Ethiopia),P. xylopoda Lack, spec. nova (Nigeria, Ethiopia) andP. humilis DC. (Senegal, Mali). There are indications that the two perennial species,P. abyssinica andP. xylopoda, are related to and have evolved from a primitive Central Asiatic stock in a manner parallel to many African species ofCrepis L.P. humilis, on the other hand, is a small annual plant with a high number of derived characters. The introduced species of European origin growing south of the Sahara are briefly mentioned.     

Three new species of Acanthaceae from Ethiopia

Summary  Three new species of Acanthaceae, Lepidagathis pseudoaristata Ensermu, Acanthopale aethio-germanica Ensermu, and Rhinacanthus mucronatus Ensermu, are described from Ethiopia. The three species are illustrated and their distributions mapped. The three new species are also compared to their presumed closest relatives. L. pseudoaristata is restricted to the Bale and Sidamo Regions, A. aethio-germanica is more widely distributed in Ethiopia occurring in the Kefa, Arsi, Sidamo and Bale Regions, and R. mucronatus is a local endemic restricted to the Borana area in the Sidamo Region. The conservation status of each species is also assessed.     

Leishmania (Kinetoplastida): species typing with isoenzyme and PCR-RFLP from cutaneous leishmaniasis patients in Ethiopia

Cutaneous leishmaniasis (CL) is an increasing public health problem in Ethiopia. There is a concern that it is spreading with increased incidence. In this study, we used isoenzyme electrophoresis and internal transcribed spacer one (ITS1) PCR-RFLP techniques to identify Leishmania species from CL patients in Ethiopia. We obtained isolates from 55 localized cutaneous leishmaniasis (LCL), 3 diffused cutaneous leishmaniasis (DCL) and 36 biopsy samples from 34 LCL and 2 DCL cases from All Africa Leprosy and Tuberculosis Rehabilitation and Training Center (ALERT) and clinically diagnosed CL cases from Ochollo village. Both isoenzyme and ITS1 PCR-RFLP techniques showed that Leishmania aethiopica (L. aethiopica) was the aetiologic agent in all cases. Our study also showed that ITS1 PCR-RFLP could identify Leishmania species from biopsy samples and suggests the method could be used for epidemiological surveillance of leishmaniasis in Ethiopia and for species-specific diagnosis.     

Divergent and reticulate processes in evolution of Ethiopian Lophuromys flavopunctatus species complex: evidence from mitochondrial and nuclear DNA differentiation patterns

Molecular study of mitochondrial and nuclear genes and cytogenetic analysis were performed to examine possible patterns of speciation in the diverse Lophuromys flavopunctatus species complex of Ethiopia. Phylogenetic analysis of mtDNA data resulted in an unresolved bush of ten deeply diverged haplotype groups corresponding to potential species either well supported by various types of character or 'cryptic'. The cytogenetic analysis showed representatives of five of these mtDNA lineages to share an identical karyotype (2 n  = 70, NFa = 84), that has not been found previously in Ethiopia. One of them, L.  cf.  sikapusi , being a member of the L. flavopunctatus species complex, demonstrates remarkable morphological similarity to representatives of another species complex, L. sikapusi s.l ., which might be considered as a result of convergent evolution in analogous environments. Analysis of RAPD data suggests that at least two mtDNA types might have been subject to interspecific transfer due to hybridization. In the case of two sympatric haplotypes of L. brunneus we may assume that the contemporary pattern of variation between them can be explained by relatively recent hybridization with another distinct species, L. flavopunctatus . The formation of two groups belonging to distinct mitochondrial lineages within northern populations could be associated with more complex processes including ancient hybridization.  © 2004 The Linnean Society of London, Biological Journal of the Linnean Society , 2004, 83 , 301–316.     

Liverworts of southwest Ethiopian montane forests: ecological and biogeographical notes

Abstract

Ethiopia has diverse topographic features and climatic conditions with a diverse flora. The liverwort flora of southwest Ethiopia is practically unknown, despite a favourable climate and the occurrence of suitable ecosystems such as montane rainforests. During an ecological study of diversity patterns of bryophytes and vascular plants in relation to land use, we recorded many bryophyte species. In this paper we report the finding of 89 species of liverworts, and give short ecological notes and describe the distribution (locally and in Africa) for each species. Of these, 51 species are newly reported from Ethiopia. It is thus obvious that Ethiopia is considerably richer in liverworts than might be expected from previous checklists.     

Bufadienolides from Drimia robusta and Urginea epigea (Hyacinthaceae)

Two bufadienolides, 6beta-acetoxy-3beta,8beta,14beta-trihydroxy-12-oxobufa-4,20,22-trienolide and 14beta-hydroxybufa-3,5,20,22-tetraenolide were isolated from the dichloromethane extract of the bulbs of Drimia robusta and the methanol extract of the bulbs of Urginea epigea, respectively. The bulbs of Drimia robusta also yielded several known compounds, 6beta-acetoxy-3beta,8beta,12beta,14beta-tetrahydroxybufa-4,20,22-trienolide (12beta-hydroxyscillirosidin) from the dichloromethane extract and three common aromatic acids, 4-hydroxy-3-methoxybenzoic acid, 3,4-dihydroxybenzoic acid, and trans-3-(4'-hydroxyphenyl)-2-propenoic acid from the ethyl acetate extract.     

Two new species of Acacia (Leguminosae–Mimosoideae) from Ethiopia and Yemen

Two new species of Acacia belonging to subgenus Acacia, A. origena from the high lands of N Ethiopia and Yemen and A. prasinata from the Rift Valley in central Ethiopia are described. The external morphology of the latter species is shortly described.     

Synopsis of Satanocrater (Acanthaceae)

Four species are recognized in the tropical African genus Satanocrater: S. fellatensis (= S. berhautii) in Sudan, Ethiopia and Guinea, S. ruspolii in Ethiopia, Somalia and Kenya, S. somalensis (= S. coccineus) in Ethiopia and Somalia, and S. paradoxus in Ethiopia, Somalia and Kenya. Three lectotypes and one neotype are selected. A key to the species and an illustration of S. ruspolii are provided.     

On the probable composition of ‘Jamaican stone’ aphrodisiac

A dangerous aphrodisiac, commonly known as ‘Jamaican stone’, banned by the U.S. Food and Drug Administration, has been studied by vibrational spectroscopy in order to solve the controversy on its composition. The results of the ATR-FTIR analysis revealed the presence of the α-pyrone ring, which is characteristic of bufadienolides from toad venom and bulbs of squill (Drimia maritima (L.) Stearn). This conclusion was reached after a comparative study with the spectra for phytochemicals derived from gambir and cat’s claw, two Uncaria species also preconized as aphrodisiacs and deemed as possible constituents of the ‘stone’. Owing to their physiologic similarities to digoxin, bufadienolides have been shown to produce a toxic profile similar to that of digoxin, although the lack one of the side chains found on digoxin should allow the use of hemodialysis to treat ‘Jamaican stone’ overdose.     

Host range evaluation of the leaf-feeding beetle,Zygogramma bicolorata and the stem-boring weevil,Listronotus setosipennis demonstrates their suitability for biological control of the invasive weed,Parthenium hysterophorus in Ethiopia

The invasive weed, parthenium (Parthenium hysterophorus L.) (Asteraceae: tribe Heliantheae), damages agriculture, adversely impacts biodiversity and is hazardous to human and animal health in Ethiopia. The host range of two natural enemies, a leaf-feeding beetle, Zygogramma bicolorata (Coleoptera: Chrysomelidae) and a stem-boring weevil, Listronotus setosipennis (Coleoptera: Curculionidae) was evaluated for biological control of the weed in Ethiopia. The specificity of Z. bicolorata and L. setosipennis was assessed against 29 and 31 non-target plant species, respectively. The host range of Z. bicolorata and L. setosipennis was first assessed using no-choice tests to examine their oviposition and feeding response on non-target plants. Although oviposition by Z. bicolorata occurred on six non-target species in four Asteraceae species in no-choice tests, it was significantly lower than on parthenium and no larvae developed. Zygogramma bicolorata nibbled the leaves of one of the five niger seed (Guizotia abyssinica L. – an oil seed crop closely related to parthenium) cultivars tested, but feeding and oviposition were significantly less than on parthenium. Furthermore, choice tests indicated that Z. bicolorata did not oviposit nor feed on G. abyssinica when parthenium was present. In no-choice tests, L. setosipennis did not oviposit on any of the non-target species assessed. Mean oviposition on parthenium was 39.0?±?3.4 eggs per plant whereas no eggs were laid on any of the 31 species tested. Based on these and other host range tests, permission was obtained to field release Z. bicolorata and L. setosipennis in Ethiopia.     

Two new species of Chascanum (Verbenaceae) from NE Africa

Two new species, Chascanum sulcatum and C. obovatum are described and illustrated, one occurring in Ethiopia and Somalia, the other in Ethiopia and N Kenya.     

Leishmania aethiopica: identification and characterization of cathepsin L-like cysteine protease genes

There is limited information on the biology and pathogenesis of Leishmania aethiopica, causative agent of cutaneous leishmaniasis (CL) in Ethiopia. In this study we have identified and characterized two cathepsin L-like cysteine protease genes, Laecpa and Laecpb, from L. aethiopica. The predicted amino acid sequence of Laecpa and Laecpb is more than 75% identical with homologous cathepsin L-like cysteine protease genes of other Leishmania species and less than 50% identical with human cathepsin L. Laecpa is expressed predominantly in the stationary, and to a lower level, during the amastigote stage while Laecpb is specifically expressed in the stationary stage of L. aethiopica development. Phylogenetic analysis showed that the two genes are grouped into separate clades which are the result of gene duplication. The isolation of these genes will be useful in developing Leishmania species specific diagnostics for molecular epidemiological studies and serves as a first step to study the role of cysteine proteases in L. aethiopica pathogenesis.     

Sesbania melanocaulis, sp. nov. (Leguminosae subfam. Papilionoideae) from SW. Ethiopia

Sesbania melanocaulis Bidgood & Friis sp. nov., is described from a mosaic of humid montane forest, forest margins, evergreen bushland and farmland in the Kefa and Welega Regions of SW. Ethiopia. The new species is a very distinctive small tree which is also widely used as a hedge plant throughout SW. Ethiopia. It belongs to subgen. Sesbania and resembles the widespread Sesbania sesban from which it differs most conspicuously in the dark purplish brown to almost black bark of the stems which are pilose to pubescent when young, the large pale tomentose stipules and the uniformly yellow flowers (dark dotted in S. sesban ). The importance of SW. Ethiopia as a local centre of endemism has been confirmed by several recent studies, including preparatory work for the Flora of Ethiopia and Eritrea. The new species of Sesbania is only one of several leguminous trees which have been taken into domestication in Ethiopia.     

New and noteworthy species of Indigofera (Leguminosae) from NE Africa

Six new species of Indigofera are described: I. eremophila Thulin from E Ethiopia, I. mooneyi Thulin from the highlands of SW Ethiopia, I. boranica Thulin from SE Ethiopia and NE Kenya, I. gyrata Thulin and I. ammophila Thulin from NE Kenya, and I. cana Thulin from north–central Ethiopia. I. cavallii Chiov., previously known only from the type from S Somalia, is reported also from NE Kenya.     

Bufadienolides from the southern African Drimia depressa (Hyacinthaceae: Urgineoideae)

Two bufadienolides, 3beta,16beta-dihydroxy-5beta-bufa-20,22-dienolide and 16beta-hydroxy-5beta-bufa-20,22-dienolide-3beta-O-beta-d-galactoside, have been isolated from bulbs of the poisonous South African geophyte Drimia depressa (Hyacinthaceae).