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1.
Eighteen new species of Euphorbia subgenus Euphorbia are described and their relationships discussed. All are endemic to Somalia, with limited distributions in the northern Regions. One, E. phillipsioides , has been identified mistakenly for some time as E. phillipsiae , which is shown to be conspecific with E. golisana. E. xylacantha , considered by N. E. Brown to be synonymous with E. monacantha , is reinstated as a distinct but variable species.  相似文献   

2.
A small succulent, spiny Euphorbia is described as a new species, E. patentispina , endemic to Somalia, with a limited distribution in the northeast region of Bari. Its relationship to other species of the same group—those producing subsessile capsules and a single spine from each spine shield—occurring in northern Somalia is discussed.  相似文献   

3.
Two small species of succulent, spiny Euphorbia are described as new, both with limited distributions, E. ammophila from the coastal plain of eastern Somalia, and E. densispina from the mountain ranges of the northeast.  相似文献   

4.
A small shrub, Euphorbia bariensis related to E. arbuscula , a sturdy shrub, E. pachyclada related to E. consobrina and E. nubica , and one with conspicuous bracts, E. papilionum related to E. cameronii , are described as distinctive new endemic-species from northeast Somalia. A new endemic, E. dhofarensis related to E. larica , is also described from the Dhofar region of Oman.  相似文献   

5.
Heliotropium subspinosum sp. nov., from the coastal and subcoastal zones of Yemen, Oman and Somalia, is described and illustrated. This is a woody species with small leaves, and particularly the only 1–4–flowered inflorescences, the axes of which become subspinescent, are remarkable in the genus. H. laxum sp. nov., a slender shrublet from central Somalia, is described, and H. personatum sp. nov., a shrublet that is widespread and scattered, particularly on gypseous ground, in eastern Ethiopia, most parts of Somalia and in southern Yemen, is described and illustrated.  相似文献   

6.
The new species Polygala praetermissa , a dwarf perennial herb growing in stony places on limestone, and P. dasanensis , a shrublet apparently confined to gypsum, are described. Both species occur in the Cal Miskaat Range in north-eastern Somalia, but P. praetermissa has a wider distribution in northern Somalia.  相似文献   

7.
The new species Basananthe aciphylla , a thorny shrublet from central Somalia, is described and illustrated. Its closest relative is the likewise spinescent NE African endemic B. berberoides .  相似文献   

8.
The six new species Convolvulus scopulatus, a shrub from gypseous semidesert coastal plains in northern Somalia, Astripomoea procera, a woody climber in Acacia-Commiphora bushland on sand in south-central Somalia, Ipomoea hiranensis, a prostrate or climbing shrublet in Acacia-Commiphora bushland in rocky places on sandstone in south-central Somalia, Ipomoea galhareriana, a woody climber in bushland on sand in central Somalia, Ipomoea pogonantha, a woody climber in bushland usually on red soil over limestone in eastern and southern Ethiopia, southern Somalia and northern Kenya, and Ipomoea corrugata, a herb with trailing stems in bushland on sandy soil in south-central Somalia, are described, and illustrations are provided for most of them. The new combinations Ipomoea ovatolanceolata (= I. adenoides var. ovatolanceolata) and Merremia obtusa (= M. ampelophylla subsp. obtusa) are made, and a new synonymy is provided for M. ampelophylla. Merremia ellenbeckii is neotypified and M. lobata is placed in synonymy.  相似文献   

9.
Euphorbia venkatarajui, a new succulent species of Euphorbiaceae, is described from Kurnool district of Andhra Pradesh state, India. The new species belongs to the subgenus Euphorbia, and it closely resembles Euphorbia gokakensis S.R. Yadav, Malpure and Chandore and E. caducifolia Haines., but differs in certain distinct characters.  相似文献   

10.
Euphorbia spissa, sp. nov., a tree known from a single population on a rocky limestone slope in northern Somalia, is described and illustrated. The species is compared with the widespread E. tirucalli, as well as with E. cameronii and E. bariensis (endemics in Somalia), E. arbuscula (endemic on Socotra), and E. uzmuk (endemic in northern Yemen).  相似文献   

11.
This study investigated whether Euphorbia subgenus Chamaesyce subsection Acutae contains C(3)-C(4) intermediate species utilizing C(2) photosynthesis, the process where photorespired CO(2) is concentrated into bundle sheath cells. Euphorbia species in subgenus Chamaesyce are generally C(4), but three species in subsection Acutae (E. acuta, E. angusta, and E. johnstonii) have C(3) isotopic ratios. Phylogenetically, subsection Acutae branches between basal C(3) clades within Euphorbia and the C(4) clade in subgenus Chamaesyce. Euphorbia angusta is C(3), as indicated by a photosynthetic CO(2) compensation point (Г) of 69 μmol mol(-1) at 30 °C, a lack of Kranz anatomy, and the occurrence of glycine decarboxylase in mesophyll tissues. Euphorbia acuta utilizes C(2) photosynthesis, as indicated by a Г of 33 μmol mol(-1) at 30 °C, Kranz-like anatomy with mitochondria restricted to the centripetal (inner) wall of the bundle sheath cells, and localization of glycine decarboxlyase to bundle sheath mitochondria. Low activities of PEP carboxylase, NADP malic enzyme, and NAD malic enzyme demonstrated no C(4) cycle activity occurs in E. acuta thereby classifying it as a Type I C(3)-C(4) intermediate. Kranz-like anatomy in E. johnstonii indicates it also utilizes C(2) photosynthesis. Given the phylogenetically intermediate position of E. acuta and E. johnstonii, these results support the hypothesis that C(2) photosynthesis is an evolutionary intermediate condition between C(3) and C(4) photosynthesis.  相似文献   

12.
八种国产大戟属植物的核型报道   总被引:7,自引:0,他引:7  
8种大戟属Euphorbia L.植物的核型分析结果表明,大戟属不同亚属的染色体基数与其形态变 异的复杂性有一定关系。地锦草亚属subgen.Chamaesyce 3个种染色体基数分别为x=8,9,11;一品红 亚属subgen.Poinsettia两个种染色体基数均为x=7,分别为四倍体和八倍体;乳浆大戟亚属subgen. Esula 3个种,染色体基数分别为x=7,10,10。根据以前学者发表的资料分析,一品红亚属和大戟亚属 Subgen. Euphorbia的染色体基数是很稳定的,分别为x=7和x=10;通奶草E.hypericifolia为x=8 的四倍体,它不仅有染色体整倍性的变异,还有异基数性的变化。结合以前学者的研究,笔者支持x= 10为大戟属的最原始基数的观点。齿裂大戟E.dentata和通奶草具不同的染色体倍性,猫眼草E. esula的细胞染色体数目观察证实了我国存在四倍体的居群,与欧洲和北美的植物构成一个典型的多倍体复合体。  相似文献   

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15.
作者清理采自中国南部大戟科标本过程,发现一些需增补的分类群,现报道其中2个新种:分布于广东封开县的印禅铁苋菜Acalyphawui和印禅三宝木Trigonostemonwui;2个新纪录种:分布于云南勐海县的短序白桐树Claoxylonsubsessiliflorum和生长于海南南沙群岛的南沙大戟Euphorbiareniformis;1个近代生长于广东、贵州和四川的归化种-桃叶猩猩草Euphorbiaheterophylla,而将依据四川渡口的标本命名的柳叶大戟E.epilibiifolia作为它的新异名.  相似文献   

16.
The first species of Isoglossa known from Somalia, I. congesta is described om material from central Somalia and SE Ethiopia. It is related to I. parvifolia Rendle, occurring in E Ethiopia, but differs in the contracted inflorescences and long calyx lobes with long glandular hairs.  相似文献   

17.
The new species Salvia geminata , a dwarf shrublet from rocky coastal slopes of the Mahrah Region in Yemen, is described and illustrated. A remarkable feature of the species is that the upper thecae of the stamens are inflexed and connate, a condition that seems to be previously unknown in the genus. The apparently closely related S. areysiana , previously known only from the area of Jebel Areys in the Abyan Region, is reported also from the Hadramaut Region.  相似文献   

18.
Taxonomic revision of South American species ofGrindelia Willd. has revealed two new species from Uruguay:G. rupestris, an erect subshurb with crowded obovate denticulate leaves, subsessile heads, and pappus composed of numerous awns, andG. linearifolia, a prostrate shrublet with small entire linear leaves. Both species are described and illustrated. A key for the UruguayanGrindelia species is provided.  相似文献   

19.
Bauhinia leucantha sp. nov. is described from central Somalia. The new species is related particularly to B. ellenbeckii in Ethiopia and Somalia, B. teitensis in Kenya, and B. natalensis in eastern South Africa. B. somalensis is reduced to a synonym of B. ellenbeckii and the distribution of this species is shown to extend to northern Somalia.  相似文献   

20.
A new species of the genus Erythrochlamys is described: E. frulicosa from Somalia and Ethiopia. An interesting variation in E, leucosphaera is also discussed.  相似文献   

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