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1.
Thulin, M. & Hjertson, M. 1995. Echidnopsis globosa sp. nov. (Asclepiadaceae-Stapelieae) from Yemen. — Nord. J. Bot. 15: 261–262. Copenhagen. ISSN 0107–055X.
The new species Echidnopsis globosa from rocky hillsides on limestone in the Hadramaut Region in Yemen is described and illustrated. It belongs to a group of species including E. squamulata from Yemen and E. ericiflora from Kenya, but is unique in the genus by its almost perfectly globose flowers.  相似文献   

2.
Tephrosia hadramautica , a new species from the coastal plain of Hadramaut in southern Yemen, is described and illustrated. T. geminiflora , previously regarded as an endemic of Hadramaut, is reduced to a synonym of T. suhtriflora .  相似文献   

3.
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   

4.
The new species Cucumis canoxyi , growing on limestone rocks in the Hadramaut Region of southern Yemen, is described and illustrated. The species is the second known member of Cucumis to be without tendrils.  相似文献   

5.
The two new species Pentzia somalensis , from areas of gypseous soil in northern Somalia, and P. arabica from the limestone plateau of Hadramaut in southern Yemen, are described and illustrated. P. somalensis is the only member of Anthemideae known from Somalia, and the occurrence of Pentzia on both sides of the Gulf of Aden in the Horn of Africa region represents a major extension of the distribution of the genus that is otherwise restricted to southern Africa except for two species in Morocco, Algeria and Tchad.  相似文献   

6.
Thulin, M. 1995. Indigofera rubromarginata sp. nov. (Leguminosae) from southern Arabia, with a note on I. eremophila. — Nord. J. Bot. 15: 519–521. Copenhagen. ISSN 0107–055X.
The new species Indigofera rubromarginata , widespread along the coast of southern Arabia in Yemen and Oman, is described and illustrated. The closely related I. eremophila , previously known only from eastern Ethiopia and Somalia, is reported also from Yemen.  相似文献   

7.
Thulin, M. 1995. A new species of Campylanthus (Scrophulariaceae) from Yemen. — Nord. J. Bot. 15: 191–192. Copenhagen. ISSN 0107–055X.
Campylanthus antonii , a new species from the Mahrah Region in Yemen, is described and illustrated.  相似文献   

8.
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   

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.
Grünig CR  Sieber TN 《Mycologia》2005,97(3):628-640
Acephala applanata gen. et sp. nov. is described. A. applanata is a dark-septate endophyte (DSE) of conifer roots and belongs to the Phialocephala fortinii species complex. Several genetic markers, including isozymes, inter-simple-sequence-repeat (ISSR) fingerprints, single-copy restriction fragment length polymorphisms (RFLP) and sequences of the internal transcribed spacers (ITS), let us unambiguously separate isolates of A. applanata from isolates of P. fortinii s.l. and other dark-septate endophytes. Alleles at four RFLP loci and two fixed nucleotides in the ITS region were diagnostic for A. applanata. One of the fixed nucleotides resulted in the addition of an Afa I restriction site. PCR amplification with primers prITS4 and the newly developed primer PF-ITS_F (ACT CTG AAT GTT AGT GAT GTC TGA GT) and restriction digestion with Afa I yielded three fragments (203 bp, 117 bp, 56 bp) in A. applanata but only two (260 bp and 117 bp) in P. fortinii s.l. Population differentiation (GST) between A. applanata and other cryptic species of P fortinii was pronounced, and the index of association (IA) did not deviate significantly from zero, showing that recombination occurs or had occurred in A. applanata. Although isolates of A. applanata never were observed to sporulate, it can be distinguished morphologically from P fortinii s.l. by the scarcity of aerial mycelium, significantly slower growth and denser mycelium on cellophane overlaid on water agar. These phenotypic characteristics, combined with diagnostic RFLP alleles and/or PCR-RFLP of the ITS fragment with the fixed Afa I restriction site, unequivocally allow identification of A. applanata.  相似文献   

11.
The genetic structure of the root endophytes Phialocephala fortinii s.l. and Acephala applanata was analyzed in two undisturbed forests. A total of 606 strains isolated from surface-sterilized, fine roots of Picea abies and Vaccinium myrtillus were examined. Two new cryptic species of P. fortinii were recognized and host specialization of A. applanata was confirmed. This species was almost exclusively isolated from roots of P. abies. The index of association did not deviate significantly from zero within any population, suggesting that recombination occurs or had occurred. Significant gene but no genotype flow was detected among study sites for P. fortinii s.l. In contrast, several isolates of A. applanata with both identical multi-locus haplotype and identical ISSR fingerprint were found in both study sites indicating genotype flow or a recent common history.  相似文献   

12.
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   

13.
A dramatic decline averaging 43% over a 4‐year period has occurred in tree Euphorbia (Euphorbia tetragona and Euphorbia triangularis) populations on the Great Fish River Reserve, South Africa. These changes are evident from data gathered by general vegetation monitoring methods as well as from a focused study of four tree Euphorbia populations. The decline from 2003 to 2007 was more marked for E. triangularis than for E. tetragona and was accompanied by a general absence of seedlings and a reduced presence of younger age classes of both species, decreasing the proportion of younger trees in the populations. The role of megaherbivores, specifically the black rhinoceros, in these changes is well established. However, the impact of baboon activity, leading to damage to tree crowns and upper branches, is also substantial, especially on E. triangularis populations. Damaged crowns were recorded significantly more often for E. triangularis than for E. tetragona, and the damage frequency increased with decreasing tree height. Thus, our work provides the first evidence that these two closely related Euphorbia species may be affected differently by herbivory.  相似文献   

14.
A small prostrate herb, Euphorbia salsicola , a woody shrublet with curious tubers, E. scatorhiza , and a small tree with decorative bracts, E. thulinii , are described as new species of Euphorbia. Within subgenus Lyciopsis the morphological variability of E. cuneata in Somalia is discussed and a new subspecies cretacea is described. E. gypsophila , a closely related but distinct species found only on gypsum is also described as new, together with E. dunensis , a shrublet from the coastal dunes and E. tripartita , another shrub in the same subgenus related to E. matabelensis. As far as present records show, all the new taxa are endemic in Somalia.  相似文献   

15.
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   

16.
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   

17.
Euphorbia gokakensis, a new succulent species of Euphorbiaceae, is described from the Belgaum district of Karnataka, India. The new species belongs to Euphorbia subgen. Euphorbia, and closely resembles Euphorbia caducifolia Haines. However, it is distinguished by its characteristic dwarf habit forming a compact cushion that hardly exceeds 50 cm in height.  相似文献   

18.
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   

19.
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   

20.
Abstract. The chorion of the egg in Callosobruchus maculatus (Coleoptera: Bruchidae) provides protection but also has to allow exchange of respiratory gases. A single opening in the chorion (the egg pore) allows diffusion of gases, and young larvae die if the egg pore is blocked. Comparison of respiration rates using a Gilson respirometer showed an increase in oxygen uptake from the first to the seventh day after the egg was laid; the increase was from 6.8 to 11.2 pl/egg/day in a Brazil strain and from 8.6 to 23.5 pl/egg/day in a Yemen strain. The Yemen strain had double the metabolic rate of Brazil-strain insects in the larvae, which are exposed to seed toxins, but not in the non-feeding adults. It is suggested that the higher metabolic rate in the Yemen larvae is related to their ability to develop in seeds that are toxic to the Brazil strain. The egg pore also differed in size and shape between the two strains. The egg pore was cylindrical in the Brazil strain, but shorter and funnel-shaped with an increased external diameter in the Yemen strain. Calculation showed that the different shape and size of the Yemen egg pore would allow a 2–3-fold increase in gas conductance compared with the Brazil strain, and this increase was consistent with the enhanced oxygen requirement of the Yemen larvae, which was a little over twice that of the Brazil larvae at 7 days. The anatomy of egg pores in Cmaculatus thus seems to represent a trade-off between two functions, allowing adequate gas exchange while maintaining the protective function of the chorion.  相似文献   

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