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1.
The sect.Cortusina (Dc.)Harv. s.l. is divided into the sectt.Cortusina (Dc.)Harv. s. str. andReniformia (Knuth)Dreyer, comb. nov.,P. cortusifolium L'Hérit.,P. crassicaule L'Hérit.,P. echinatum Curt.,P. magenteum J. J. A. Van der Walt, andP. sibthorpifolium Harv. remain in the sect.Cortusina s. str., while the speciesP. album J. J. A. Van der Walt,P. dichondrifolium Dc.,P. odoratissimum (L.)L'Hérit.,P. reniforme Curt., andP. sidoides Dc. are removed from the sect.Cortusina s.l. and included in the revised sect.Reniformia. Both sections are well characterized by morphological, anatomical, karyological and palynological features. The chromosomes ofCortusina s. str. are small and based upon x = 11; those ofReniformia are larger and based upon x = 8. The size and surface sculpture of the pollen grains differ markedly between the two sections. Flavones and hydrolysable tannins occur in sect.Reniformia, but are absent in sect.Cortusina s. str. After hydrolysis hydroxybenzoic acids, which are present in large amounts inReniformia, occur only in traces inCortusina. The two sections also occupy distinctly different geographical areas. A close relationship between sect.Reniformia and some species of sect.Ligularia (Sweet)Harv. is indicated by the occurrence of artificial hybrids.  相似文献   

2.
An investigation of pseudocopulation behaviour in species ofOphrys from southern Spain confirms the close relationship betweenCampsoscolia ciliata (Scoliidae) andOphrys speculum, and betweenEucera nigrilabris (Apoidea) andOphrys tenthredinifera. It could be demonstrated thatEucera barbiventris is the pollinator ofOphrys scolopax subsp.scolopax, whereas other species ofEucera andTetralonia which are active at the same time show no interest at all for the flowers of this species. Special attention was paid to the forms of the taxonomically confusedOphrys fusca group:O. fusca s. str.,O. iricolor, O. omegaifera andO. atlantica. WhileO. fusca s. str. is widespread, small-flowered and has late anthesis,O. iricolor has very large flowers and early anthesis. Each of the four members ofO. fusca agg. in S. Spain is pollinated by a different bee, and selective experiments show that each of these four species of bees is specifically attracted only to one of theOphrys species:Andrena flavipes is the pollinator ofO. fusca s. str.,Colletes cunicularius infuscatus ofO. iricolor, Anthophora atroalba ofO. omegaifera, andChalicodoma parietina ofO. atlantica. These four pollinators belong to 4 different bee families (Andrenidae, Colletidae, Anthophoridae, Megachilidae). As this type of pollination represents a very effective pregamic isolation mechanism, these four taxa ofOphrys fusca agg., at least in southern Spain, behave and should be regarded as genuine species.
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3.
Flower polymorphism in 15 ItalianOphrys populations (N = 282) was analysed in detail. Statistical and graphical evaluation of data demonstrates morphological relationships and amount of hybrid character coherence.O. bertolonii s. str. andO. atrata are stable parental taxa, but occasionally form hybrids and hybrid swarms. Much evidence suggests that it was through such homogamic hybridization, involving these and other species ofOphrys, that the stabilized taxaO. bertoloniiformis andO. promontorii (ecologically different, but sympatric with the parents on Gargano), andO. benacensis (geographically separated from the parents in the Insubric region) originated. These differentiation-hybridization cycles are linked to the break-down and new establishment of incomplete prezygotic crossing barriers (e.g. different flower biology, flowering time, habitat preference).
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4.
The genusScrophularia in the Iberian Peninsula and Balearic Islands comprises two sections,Scrophularia andCanina G. Don. Analyses were carried out on flower production, flower duration and their sexual phases, pollen and nectar production together with observations on their pollinators. Nectar production is correlated with corolla size and pollen production with anther size. The taxa of sect.Scrophularia show greater nectar and pollen production than those of sect.Canina. Also, those of the first section produce more ovules per ovary than those of the second group, production being correlated with the ovary size.Some observations on floral and reproductive biology in some species ofScrophularia from the Iberian Peninsula and the Balearic Islands. I.  相似文献   

5.
The chromosome numbers of five species ofOrobanche sect.Orobanche (O. alsatica, O. laserpitii-sileris, O. loricata, O. salviae, O. teucrii) are reported for the first time and previous counts could be verified in ten other species. Now the chromosome numbers of all species of sect.Orobanche occurring in Central Europe are known: they are diploid (2n = 38) with the exception ofO. gracilis (tetra- and hexaploid, aneusomatic).
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6.
Seeds of eight species ofSilene s. str. in Korea were examined with a dissecting stereomicroscope and a scanning electron microscope (SEM) to evaluate the systematic significance of seed coat microstructure. The seeds ofSilene s. str. were characterized by triangular or reniform shape, planed or concave dorsal surface in outline, tuberculate or colliculate testa, and sinuated cell margin. Based on the degree of grooves and invagination at dorsal surface, the seeds of the examined taxa ofSilene s. str. fall into two distinct groups: (I) dorsal grooves inconspicuous, surface planed (Silene jenisseensis andS. repens), (II) dorsal grooves conspicuous, surface concave (six remaining taxa). Within each group, seeds of all species may be further distinguished based on shape, size, and testa surface sculpturing. A key to the different species or groups of species is provided, and the systematic significance between/among the taxa is also briefly discussed.  相似文献   

7.
Fruits ofDipsacaceae are single-seeded, have bristle-shaped calyx segments and are tightly enclosed by four fused bracts forming an epicalyx. Comparative morphological and anatomical studies reveal a great diversity of epicalyx and calyx, often relevant to fruit dispersal. The present contribution deals with theScabiosa group of genera, the core of theScabioseae tribe. Most of its taxa develop a diaphragma from a meristem on the inside of the epicalyx. This diaphragma, together with the lower part of the epicalyx encloses the fruit proper, whereas the upper parts form a so-called epi-diaphragma (ed) and a ± hyaline corona. Differences of the epicalyx with respect to the size and position of the ed, elaboration of the corona, origin of pits (=foveoles) and other morphological and anatomical specializations can be demonstrated. Together with palynological and karyological data these new facts support an improved concept of relationships and systematics for the taxa studied:Scabiosa sect.Scabiosa and sect.Cyrtostemma are closely related and should be united to form the genusScabiosa s. str.;Pycnocomon can be maintained as an independent genus, sister toScabiosa sect.Trochocephalus which then has to be treated as a genus,Lomelosia. In contrast, the following genera have to be included inLomelosia:Tremastelma asLomelosia sect.Callistemma, andScabiosiopsis as part ofLomelosia sect.Lomelosia. Pseudoscabiosa deviates in so many features that it has to be excluded from the redefinedScabioseae s. str.  相似文献   

8.
Chromosome counts are reported for several E. Alpine taxa ofEuphrasia sect.Euphrasia. First records of diploidy for small-flowered taxa are 2n = 22 forE. inopinata andE. sinuata, related toE. minima (4 x). Aberrant E. AlpineE. hirtella is 2 x, just as the typical W. Alpine populations of this species. Tetraploidy, 2n = 44, has been found inE. pumila, close toE. stricta (also 4 x). The limitation of ploidy levels within sect.Euphrasia to 2 x and 4 x on the chromosome base number x = 11 is confirmed.
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9.
Geranium sect.Gracilia (Geraniaceae) comprises nine species in the Andes of Venezuela and Colombia.Geranium lindenianum andG. gracilipes are synonymized withG. holosericeum. The identity ofG. multiceps is clarified. Its differences from the two Colombian species,G. santanderiense andG. lainzii, are discussed.Geranium lignosum, G. sebosum, G. stoloniferum, G. subnudicaule, andG., velutinum are now considered to be members of sect.Gracilia. The identity ofG. pilgerianum could not be clarified because the type was destroyed and other collections have not been found. Micromorphological leaf and seed characters are discussed. Six lectotypes and one neotype are designated.
Resumen  Se revisaGeranium sect.Gracilia (Geraniaceae), un grupo formado por nueve especies distribuidas por los Andes de Venezuela y Colombia. Se sinonimizanG. lindenianum y G. gracilipes aG. holosericeum. Se aclara la identidad deG. multiceps y se establecen sus diferencias conG. santanderiense y conG. lainzii, ambas esencialmente colombianas. Se aceptan en esta secciónG. lignosum, G. stoloniferum yG. sebosum, propuestos tras la descripción de la sect.Gracilia, yG. subnudicaule yG. velutinum, ya tratados por otros autores en como pertenecientes a este grupo. Por el contrario, la identidad deG. pilgerianum no ha podido ser aclarada tras la destrucción del tipo y ante la falta de otros materiales de la especie. Se estudian diversos caractere micromorfológicos, especialmente algunos referibles a la anatomía foliar y la de la semilla. Se designan seis lectótipos y un neótipo.
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10.
Morphological and cytological investigations as well as crossing experiments were carried out withRanunculus seguieri Vill. and 4 species of theRanunculus alpestris L. group (R. alpestris L.,R. traunfellneri Hoppe,R. bilobus Bertol.,R. crenatus Waldst. & Kit.). ForR. seguieri andR. alpestris, localities and distribution are given in addition to extensive diagnoses. A key to the species includes morphological characteristics and distribution data forR. traunfellneri, R. bilobus, andR. crenatus. New diagnostic characters are described. Crossing experiments betweenR. seguieri and the species of theR. alpestris group were unsuccessful. All 5 species have a chromosome number of 2n = 16, the record forR. bilobus is new. There is no statistically significant difference between the karyotypes ofR. seguieri andR. alpestris s. str. Nevertheless, according to morphological evidence and crossing experiments,R. seguieri is not closely related to theR. alpestris group.
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11.
The serological reaction of seed proteins provides evidence for a partly new systematic arrangement ofCytisus sect.Trianthocytisus and ofCytisus s.l. Proposed modifications agree with recent advances in morphological taxonomy. Sect.Trianthocytisus includes only two species,C. villosus andC. aeolicus. Its position is central within the genus, and this fact agrees with the proposed retypification ofCytisus (type species:C. villosus).C. emeriflorus, formerly included in the same section, constitutes the monospecific sect.Emeroides, which is intermediate towards the genusLembotropis. This is serologically isolated and includes onlyL. nigricans. It is confirmed thatC. sessilifolius should be removed from the genusCytisus as a monospecific genus:Cytisophyllum Lang which is closely allied toHesperolaburnum and toPodocytisus, the most primitive genera ofGenisteae.  相似文献   

12.
Ovule and especially seed anatomy of eight species ofCochlospermaceae, Bixaceae, Cistaceae, Monotoideae, Pakaraimaeoideae (two subfamilies ofDipterocarpaceae), andSarcolaenaceae were investigated. All representatives show a bixoid chalazal region in the seed as probable exclusive synapomorphy among angiosperms. The palisade layer of the exotegmen is curved inwards at its proximal end and forms a dome-shaped structure. A plug of hypostase tissue with an annulus/core structure fits into this dome. Moreover, two additional tissue types in the hypostase can be found in some representatives of the group. These and other micromorphological, wood anatomical, and floral morphological characters, indicate that the taxa form a monophyletic group close toMalvales s. str. The form of the starch grains in the endosperm is compared and is described for the first time forPakaraimaea (Dipterocarpaceae) andLeptolaena (Sarcolaenaceae). The position ofDiegodendron close toBixa and the presumably more distant positions ofMuntingia andNeuradaceae are discussed.  相似文献   

13.
Morphological and RAPD markers were used to assess the relationships among nodulating and non-nodulating species of AfricanAcacia. Non-nodulating species of AfricanAcacia are only found within subg.Aculeiferum sect.Monacanthea. African species of sect.Monacanthea examined were found to form a group distinct from the other African species examined on a morphological and molecular basis. All lack the ability to nodulate, suggesting that non-nodulation may be used as a taxonomic tool. The species of sect.Aculeiferum were separated by RAPD and morphological analysis into two groups depending on whether they were armed with prickles in pairs and/or prickles in threes, or solitary. A third group of species was identified within sect.Acacia: further subdivision of this group was achieved into subsectt.Pluriseriae andUniseriae. The position ofA. albida relative to other AfricanAcacia species was found to be distinct but not totally independent of the genus. The partitioning and distribution of the genetic variability within the genus is further elucidated by the RAPD analysis of populations ofAcacia species. A population analysis ofA. polyacantha demonstrated geographical and site-specific variation.  相似文献   

14.
A phylogenetic analysis of 25 species, representing eight genera of theRubieae tribe (Rubiaceae), has been made using the DNA sequence of the chloroplastatp B-rbc L intergene region. Six tropical genera from other tribes ofRubiaceae have been used as outgroups. Whatever the method of analysis (distance, parsimony or maximum likelihood), five groups are clearly separated and described as informal clades. Their relative relationships are not clearly resolved by the parsimony analysis, resulting in eight equally parsimonious trees, 327 steps long, with a consistency index (CI) of 0.749 (excluding uninformative sites). TheRubieae tribe appears monophyletic from the data available. Some new and partly unexpected phylogenetic relationships are suggested. The genusRubia forms a separate clade and appears to be the relatively advanced sister group of the remaining taxa. TheSherardia clade also includes the generaCrucianella andPhuopsis. Galium sect.Aparinoides appears closely attached to theAsperula sect.Glabella clade. The remaining taxa ofGalium are paraphyletic:Galium sect.Platygalium (in theCruciata clade) is linked to the advanced generaCruciata andValantia; the more apomorphic groups ofGalium form theGalium sect.Galium clade, including the perennial sectionsGalium, Leiogalium, andLeptogalium as well as the annual (and possibly polyphyletic) sect.Kolgyda.  相似文献   

15.
P. J. McFadyen 《BioControl》1987,32(4):377-379
Foliage-feeding beetles of the genusAnacassis [A. phaeopoda Buzzi,A. fuscata (Klug),A. fuscata var.unicolor (Burmeister),A. cribrum (Klug) andA. dubia (Boheman)] were collected fromBaccharis spp. andBaccharidastrum spp. in South America. Specificity studies showed that they were restricted to these 2 host genera. Between 1974 and 1976 these species were introduced into Australia for the control ofBaccharis halimifolia. A. phaeopoda andA. fuscata were first released in 1976. One field colony ofA. fuscata persisted for up to 3 years but no recoveries ofA. phaeopoda were made after the 1st field generation. The other species died out in quarantine and were not released.   相似文献   

16.
Jun Wen 《Brittonia》1993,45(1):47-55
Aralia, described by Linnaeus, remains a poorly defined genus. Many satellite genera ofAralia have been proposed, and some have been accepted without critical evaluation. These genera includeCoudenbergia, Megalopanax, Parapentapanax, andPentapanax. This study examined the historical background of the establishment of these genera and their diagnostic characters. It was found that (1)Aralia s. str. is a relatively diverse genus; (2) the separation ofPentapanax andParapentapanax fromAralia is unsubstantiated; (3)Megalopanax is synonymous withCoudenbergia; and (4) the boundaries betweenAralia and bothCoudenbergia andPentapanax intergrade. It is proposed, therefore, to mergeCoudenbergia, Parapentapanax, andPentapanax withAralia, which has nomenclatural priority.Aralia is herein defined as consisting of those species in Araliaceae with pinnate leaves, articulated rachises, five to eight-merous flowers, petals imbricate in buds, and articulated pedicels. The revised generic concept requires the following new combinations or new names:Aralia castanopsisicola, A. franchetti, A. gigantea, A. laevis, A. leschenaultii, A. parasitica, A. rex, A. subcordata, A. verticillata, andA. warmingiana.  相似文献   

17.
Satureja s.l. (Lamiaceae) is a large complex (ca. 225 spp.) that is variably treated as comprising from one to as many as 17 genera. The North American representatives are usually assigned toCalamintha, Clinopodium, Micromeria, Piloblephis, orSatureja. A recent chloroplast DNA restriction site analysis indicates that inclusion ofSatureja s.str.,Micromeria, andPiloblephis in the group renders it non-monophyletic. After exclusion of these three genera, a study of morphological variation in the remainder of the complex suggests that it is best treated as three genera, two of which do not occur in North America (Cyclotrichium and “Obtegomeria” [Doroszenko, ined., to be validated else-where]). The third comprises ca. 100 species, 11 of them native to North America north of Mexico. WithSatureja s.str. excluded, the name with priority for the latter genus isClinopodium. The indigenous North American species and their more frequently used synonyms are tabulated. A new combination,Clinopodium chandleri, is made.  相似文献   

18.
Evolutionary variation of aspartate aminotransferase and superoxide dismutase isoenzymes in 14 wild and cultivated species ofPhaseolus andVigna has been studied by electrophoresis and isoelectric focusing in polyacrylamide gel. The American cultivated beans of the genusPhaseolus s. str.,P. vulgaris, P. coccineus, P. lunatus andP. acutifolius, form a homogeneous group with only minor isoenzyme variation. The genusVigna, on the contrary, proves to be heterogeneous in isozyme characters. Several clusters of taxa can be distinguished in close correspondence with modern treatments of the genus. The isoenzyme data support the inclusion of the Asian Azuki beans of subg.Ceratotropis inVigna, but argue against the transfer of the S. American speciesP. adenantha. The cowpea complexV. unguiculata s. lato of sect.Catiang forms an uniform and isolated group, distinct from other sections of subg.Vigna, and shows affinity toPhaseolus s. str. by some isoenzymes. It is suggested to removeV. unguiculata s. lato from subg.Vigna and to recognize it as a separate subg.Catiang (DC.)Jaaska & Jaaska, stat. nov.  相似文献   

19.
Androecial development of 13 species belonging to six tribes ofFlacourtiaceae has been investigated. While inScolopieae andFlacourtieae the stamens develop centrifugally, inErythrospermeae, Oncobeae andPangieae they are initiated in a centripetal sequence or a sequence that is neither distinctly centripetal nor centrifugal. The distribution of these developmental patterns coincides with the distribution of other characters (e.g. cyanogenic compounds, salicoid leaf teeth) and therefore supports a split of the family intoFlacourtiaceae s. str. (containing theScolopieae, Homalieae, Prockieae, Flacourtieae, Casearieae andBembicieae) andKiggelariaceae (withErythrospermeae, Oncobeae andPangieae) and is in accordance with results of recentrbcL studies.  相似文献   

20.
Morphological and seed protein analyses of 26 species of the generaLolium, Festuca andVulpia confirmed their close systematic affinities. Six inflorescence characters readily differentiatedFestuca fromLolium. Protein similarities betweenFestuca of sect.Bovinae and cross-pollinated species ofLolium, coupled with cytogenetic and crossability data, substantiate that they should be united into one genus.Vulpia had phenetic similarities with sect.Scariosae, Montanae andOvinae ofFestuca. Lolium, Festuca, andVulpia are most likely derived from a common ancestral form which was close toFestuca pratensis andLolium perenne.  相似文献   

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