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1.
Summary Segregation of the cytosolic Pgi2 locus was studied among progeny of the synthetic allotetraploid (L. japonicus × L. alpinus)2, the synthetic autotetraploid (L. alpinus)2, and the cultivated tetraploid species L. corniculatus L. Evidence of an original diploid duplication found within the interspecific hybrid L. japonicus × L. alpinus was also found within the synthetic allotetraploid (quadruplication of loci). Evidence suggesting quadruplication of loci was also found in the tetraploid L. corniculatus, but not in the synthetic autotetraploid (L. alpinus)2. It is suggested that the original duplication resulted from unequal crossing-over between homoeologues and that it provides evidence that L. corniculatus is a segmental allotetraploid. Quadruplication of loci in L. corniculatus could explain previously reported distorted tetrasomic ratios for segregation of qualitative characters in this species.  相似文献   

2.
The nine species of the genusAllomarkgrafia are treated synoptically, with a review of their systematics and nomenclature. Two new species,Allomarkgrafia ecuatoriana andA. insignis, and a new combination,Allomarkgrafia campanulata, are proposed here.  相似文献   

3.
In the course of monographic work in Myrtaceae it has become evident thatEugenia prismatica cannot be accommodated within any existing genus in the family. Therefore, a new genus,Curitiba, is described to contain it and the new combinationCuritiba prismatica is made.Curitiba is diagnosed by a combination of 4-angled hypanthia and fruits, ovules radiating from a central protruding placenta, and seed coats with wavy rows of papillae. A key is provided to distinguishCuritiba from the Caribbean and Mesoamerican genusMosiera, where the species also had been placed before this transfer, and from other 4-merous genera in Brazil of subtribe Myrtinae. In the Atlantic Forest of Brazil where the family Myrtaceae is one of the most species rich and ecologically important plant families, the discovery ofCuritiba reveals a unique evolutionary lineage, highlights the endemism present in the Atlantic Forest, and underscores, the urgent need for conservation of this rapidly disappearing and highly endangered biome.  相似文献   

4.
A new genus, Bobgunnia, is established in tribe Swartzieae for the African species of Swartzia. Two new combinations are made: B. fistuloides and B. madagascariensis. The new genus has seeds, unlike the remainder of tribe Swartzieae but like the other tribes of Faboideae. The systematic position of Swartzieae is reevaluated.  相似文献   

5.
Floral organogenesis and development of the tropical legume treesDalbergia brasiliensis, Machaerium villosum, Platymiscium floribundum, andPterocarpus rotundifolius were studied using scanning electron microscopy. The aims were to compare ontogenies and to elucidate if floral ontogenetic data will provide new character states diagnostic of the tribe Dalbergieae, which is considered a basal papilionoid tribe and primarily defined on fruit characters. Organ inception is principally acropetal in all taxa studied. Carpel inception is, however, consistently precocious. InD. brasiliensis sepals are initiated in an order not previously reported in Papilionoideae. It may be considered modified helical. InP. rotundifolius the inner whorl of stamens initiate in an unusual way, this is lateral two stamens first, then the two abaxial ones, and last the adaxial one, opposed to the unidirectional order usually seen in Papilionoideae. Generally the differences in flower development among the studied genera appear at initiation and late stage in ontogenesis, rather than at mid-stage.  相似文献   

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8.
The 19 species of the genus Mandevilla in Mexico and Central America are treated synoptically. New synonymy is provided and a new species, Mandevilla rigidifolia, is described.  相似文献   

9.
Six taxa of genusChamaecrista are described: In sect.Apoucouita (Bentham) Irwin & Barneby,Ch. amorimii Barneby andCh. pteropoda Barneby, both from Atlantic Bahia; in sect.Absus ser.Incurvatae Irwin & Barneby,Ch. caspariifolia Barneby andCh. linearifolia var.latifolia Barneby, both from interior Minas Gerais; in sect.Absus ser.Hedysaroides Irwin & Barneby,Ch. fulgida Barneby, from northern Goiás; and in ser.Prostratae (Bentham) Irwin & Barneby,Ch. chiquitana Barneby, from lowland Bolivia. The affinities and differential characters of each are pointed out, and all but var.latifolia are illustrated.  相似文献   

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11.
Zornia subsessilis, a new species from Serra do Cabral, Minas Gerais State, Brazil, is described and illustrated on the basis of field and herbarium studies. It belongs to Zornia section Zornia of subgenus Zornia and it appears to be restricted to “campo rupestre” (rocky fields) within the “cerrado” biome. This new species is characterized by its sessile to subsessile leaves, fruits with articles 4 to 5 mm long and with bristles up to 3.5 mm long.  相似文献   

12.
Campomanesia simulans, a new species from the states of São Paulo and Minas Gerais, Brazil, is described and illustrated.  相似文献   

13.
A new species,Pilocarpus trifoliolatus Skorupa & Pirani from Pará, Brazil, is described and illustrated. The new taxon resemblesP. microphyllus Stapf ex Wardleworth andP. alatus C. J. Joseph ex Skorupa by its winged rachis and petiole and by its dilated stigma.  相似文献   

14.
Comparative sequencing of internal transcribed spacers (ITS) and 5.8S gene of nuclear ribosomal DNA was carried out to examine phylogenetic relationships among subgenera and sections of Old World Astragalus as well as the recent segregate genera Barnebyella and Ophiocarpus. For a subset of these taxa (43 accessions), the nrDNA ITS data were supplemented by sequences from the chloroplast ndhF gene. Phylogenetic trees resulting from separate analyses of the nrDNA ITS and ndhF sequences were in conflict mainly on the position and relationships of Ophiocarpus aitchisonii, Astragalus hemsleyi, A. grammocalyx, A. coelicolor, A. capito, A. epiglottis and A. annularis. Excluding these taxa, phylogenetic analysis of a combined nrDNA ITS-ndhF data matrix was also conducted, so that in the resulting tree, most clades were more resolved and better statistically supported than those were in the separate analyses. Our results indicate that the monotypic segregate genera Barnebyella (= A. migpo), Ophiocarpus (= A. ophiocarpus) and morphologically isolated annual species A. dipelta (= Didymopelta turkestanica), A. schmalhausenii (= Sewerzowia turkestanica) and A. vicarius (= S. vicaria) are clearly nested within Astragalus. Our results confirm earlier studies that shows A. vogelii is allied with the genera Colutea and Oxytropis rather than with any Astragalus species. It is therefore excluded from Astragalus and elevated to the new generic rank and named as Podlechiella Maassoumi and Kazempour Osaloo. None of the eight traditionally recognized Astragalus subgenera Epiglottis, Trimeniaeus, Phaca, Hypoglottis, Calycophysa, Tragacantha, Cercidothrix and Calycocystis are monophyletic. Similarly, the monophyly of Podlechs new subgenera Trimeniaeus, Astragalus and Cercidothrix is not supported. Among the many species-rich sections analyzed here, only Cenanthrum, Chronopus, Laxiflori, Lotidium, Incani and Amodendron are monophyletic.  相似文献   

15.
Four species of the moss genusRacomitrium Brid. are reported from Brazil:R. subsecundum (Harv.) Wils,R. didymum (Mont.) Lorentz,R. crispipilum (Taylor) A. Jaeger, andR. visnadiae W. R. Buck.Racomitrium subsecundum is reported for the first time from South America in Brazil and Colombia. The species is fully described and illustrated.Racomitrium didymum is recorded for the first time from Brazil; the specimens previously assigned toR. crispulum (Hook.f. & Wils.) Hook.f. & Wils. represent this species.Racomitrium cucullatifolium Hampe andR. crispulum (Hook. f. & Wils.) Hook.f. & Wils. are excluded from the Brazilian bryophyte flora. All Brazilian species ofRacomitrium are briefly assessed taxonomically and bryogeographically and illustrated, and a key to their determination is given. A lectotype is selected forGrimmia didyma Mont.  相似文献   

16.
Summary An isoenzyme survey was conducted for several geographically dispersed accessions of four diploid Lotus species, L. alpinus Schleich., L. japonicus (Regel) Larsen, L. tenuis Waldst. et Kit and L. uliginosus Schkuhr, and for the tetraploid L. corniculatus L., in order to ascertain whether isoenzyme data could offer additional evidence concerning the origin of L. corniculatus. Seven enzyme systems were examined using horizontal starch gel electrophoresis. These were PGI, TPI, MDH, IDH, PGM, 6-PGDH, and ME. Lotus uliginosus had monomorphic unique alleles, that were not found within L. corniculatus, at 7 loci. These loci and alleles are: Tpi1-112, Pgm1,2-110, Pgm3-82, Mdh3-68, 6-Pgdh1-110, 6-Pgdh2-98,95, and Me2-100. Other diploid taxa contained alleles found in L. corniculatus for these and other loci. The implications of the isoenzyme data to theories on the origin of L. corniculatus are discussed.Communicated by H. F. Linskens  相似文献   

17.
A taxonomic study of the genus Otoptera (tribe Phaseoleae) is presented. This distinct genus consists of two species, O. burchellii in southern Africa (Namibia, Botswana, South Africa and Zimbabwe) and O. madagascariensis endemic to Madagascar. The two species differ in the shape and size of leaflets, size and orientation of the spur located at the base of the wing petal, and also by size of the pod. A key to the two species is provided. This study focuses mainly on the southern African O. burchellii DC., which is described and illustrated. The species name is lectotypified and the known geographical distribution is recorded for the first time.  相似文献   

18.
Brian M. Boom 《Brittonia》2005,57(2):105-107
Remijia hubbardiorum B. M. Boom, endemic to white sandcampinas orerra firme forest in the Rio Uatumã region in the State of Amazonas of north central Brazil, is described and illustrated, and its morphological differentiation with respect toR. asperula Standley is discussed.  相似文献   

19.
Passiflora cordistipula, a new species of subg.Passiflora, ser.Lobatae, from the state of Amazonas, Brazil, is described and illustrated.  相似文献   

20.
Eight new species from Brazil,Ficus acreana,F. bahiensis, F. duartei, F. duckeana, F. hatschbachii, F. lagoensis, F. laureola, andF. rupicola, are described and illustrated. The new species are compared with other species of the genus.  相似文献   

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