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1.
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   

2.
Three new species of Swartzieae are described and illustrated:Swartzia alternifoliolata, S. capixabensis, andZollernia cowanii. Swartzia apetala var.blanchetii and var.subcordata are considered to be synonyms ofS. apetala var.apetala, andS. grazielana a synonym ofS. macrostachya var.macrostachya. Keys to southeastern Brazil members ofSwartzia andZollernia are provided.  相似文献   

3.
Turner , B. L., and O. S. Fearing . (U. Texas, Austin.) Chromosome numbers in the Leguminosae. II. African species, including phyletic interpretations. Amer. Jour. Bot. 46(1) : 49-57. Illus. 1959.—Chromosome numbers for 30 African legume species have been reported. These include first reports for 28 taxa, including 12 genera (Bolusanthus, Calpurnia, Melolobium, Lessertia, Sulherlandia, Colophospermum, Guibourtia, Burkea, Julbernardia, Schotia, Piliostigma and Swartzia). The counts are discussed with respect to those previously reported for related groups, and this chromosomal information was used to construct hypothetical phyletic lines at the tribal level within the subfamilies Papilionoideae and Caesalpinioideae. A phyletic scheme for the Leguminosae (excluding the Mimosoideae) based on this evidence from chromosome studies is presented. Notable departures from previously suggested phyletic treatments include: (1) Suggestion for inclusion of genera of the Galegeae and Hedysareae with base numbers of x = 10 and 11 with the Phaseoleae and Dalbergieae. (2) Derivation of the Papilionoideae through caesalpinoid prototypes, possibly from Swartzia-like ancestors. (3) Recognition of several very old chromosomal lines stemming from the subfamily Caesalpinioideae, and the suggestion that parts of the tribes Sclerolobieae, Cynometreae, Swartzieae and Sophoreae are, perhaps, more closely related to each other and to the Papilionoideae than they are to the remaining caesalpinoid tribal lines.  相似文献   

4.
5.
Bunium is unusual in Apiaceae in having a variable cotyledon number and broad infrageneric dysploidy. To test the monophyly of the genus, phylogenetic relationships among 39 Bunium species were investigated with DNA sequence data from nuclear (nrITS) and plastid (psbA‐trnH intergenic spacer) regions. Several other taxa with a similar ecology and geography were also included in the analyses. Our results suggest that Bunium is not monophyletic. Bunium spp. in the eastern part of the study area are more closely related to the Central Asian genera Elaeosticta, Galagania, Hyalolaena, Mogoltavia and Oedibasis than to those in the western part. Our study revealed that molecular, morphological (cotyledon number and width of fruit commissure) and karyological data reveal similar patterns in the taxa studied. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 149–170.  相似文献   

6.
No study has yet been carried out on seed development in a cold desert sand dune papilionoid legume. Thus, our primary aims were to (i) monitor seed development in the cold desert sand dune species Eremosparton songoricum from the time of pollination to seed maturity, and (ii) compare seed development in this species with that in other species of papilionoid legumes. Fruit and seed size, mass and seed moisture content, and seed imbibition, germination, desiccation tolerance and water retention during development (pollination to seed maturity) were monitored in the papilionaceous shrub E. songoricum in the Gurbantunggut Desert of northwest China. The duration of seed development was 40 days. Seeds reached physiological maturity 28 days after pollination (DAP), at which time 58% of them germinated and they had developed desiccation tolerance. Seeds became impermeable 36–40 DAP, when their moisture content was about 10%. The final stage of maturation drying occurred via loss of water through the hilum. The developmental stages and their timing (DAP) in seeds of E. songoricum are generally similar to those reported for other papilionaceous legumes with a water‐impermeable seed coat (physical dormancy). In general, the developmental features of seeds with water‐impermeable coats at maturity do not appear to be specific to habitat or phylogeny.  相似文献   

7.
A karyological analysis of the so‐called primitive genera of Genisteae has shown that they have a relatively homogeneous chromosome complement: all species tend to have a somatic chromosome number 2n = 48, which can increase to 2n = 52, presumably as a result of hyperaneuploidy. Karyological data suggest that Argyrocytisus, Cytisophyllum and Petteria may be considered as distinct genera rather than being assigned to Cytisus, with 2n = 52 for the first of these and 2n = 50 for the other two genera. They may be interpreted as relict monotypic genera as a result of the presence of a stabilized aneuploidy. Karyological characters exclude a recent origin of Genisteae from Thermopsideae. On the contrary, they are consistent with the hypothesis that Genisteae and Thermopsideae are independently derived from a basic papilionoid stock, of which present day Sophoreae are the remainder. At least two lines would lead from Sophoreae to the taxa of the ‘genistoid alliance’, one to Thermopsideae and the other ‘podalyrioid alliances’ (Podalyrieae and Mirbelieae), with the prevailing basic number of x = 9, and the other to Genisteae, with a basic number of x = 12 persisting in some present day genera, including Cytisus s.l. From this lineage, a wide range of secondary basic numbers has been formed, mostly by descending aneuploidy. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 232–248.  相似文献   

8.
The cotyledon areole, which is a spot with granular projections of epidermal cells, appears on the abaxial surface and on the midvein of some legume seed cotyledons. The distribution and systematic utility of cotyledon areoles were studied by observation of 132 legume species, which represent 100 genera and are classified into 34 tribes of three subfamilies, i.e., Caesalpinioideae, Mimosoideae, and Papilionoideae. The cotyledon areole is found in many species of Papilionoideae but not in the other two subfamilies. Presence of a cotyledon areole is presumed to be an apomorphic character state in Papilionoideae from the outgroup rule.  相似文献   

9.
N othofagus palustris sp. nov. is the first record of well‐preserved leaves of Nothofagus subgenus Brassospora in New Zealand, and is described from an Oligo–Miocene leaf bed in the Gore Lignite Measures of the South Island. Nothofagus palustris is represented by relatively small and variably toothed leaves with cuticular remains that possess all the characteristic features of the subgenus, including the presence of variably sized stomata that are randomly arranged within areoles, hydathodes along the major veins and ‘bulging cells’ within the areoles on the adaxial side. Phylogenetic assessment shows that the leaves are similar to those of Australian Oligocene and Miocene species and may belong to the same clade of Brassospora. Most notably, these species share the derived feature of abundant leaf wax, a feature that is now only well developed in two New Guinean species. This and other evidence allows the possibility that the ancestor of N. palustris reached New Zealand from Australia. However, it is improbable that N. palustris or a similar species was the common ancestor of the clade of Brassospora that is now confined to New Caledonia. Ecologically, N. palustris is unusual among extant and previously described macrofossil species of Brassospora in being found in a relatively open, swampy habitat. © 2014 The Linnean Society of London, Botanical Journal of the Linnean Society, 2014, 174 , 503–515.  相似文献   

10.
The breeding system of the terrestrial orchid Eulophia alta was investigated in south Florida where it has previously been reported as an auto‐pollinated species. The effect of breeding system on seed viability and germinability and seedling development was also investigated. Incidences of spontaneous autogamy in E. alta were rare at the study site, resulting in only 7.1% of observed flowers forming capsules. In addition, hand pollination resulted in significantly greater capsule formation when flowers were subjected to induced autogamy (46.4%), artificial geitonogamy (64.3%) and xenogamy at both short (pollen source 10–100 m away; 42.9%) and long (pollen source > 10 km away; 67.9%) distances. Pollen source had little effect on seed viability and germinability or seedling growth rates. However, seed resulting from spontaneous autogamy developed more slowly than seed originating from the other treatments. These data indicate that spontaneous autogamy is rare in E. alta and that naturally forming capsules may be the result of unobserved pollination events. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 161 , 78–88.  相似文献   

11.
Premise of study: Phylogenetic relationships of the papilionoid legumes (Papilionoideae) reveal that the early branches are more highly diverse in floral morphology than are other clades of Papilionoideae. This study attempts for the first time to comprehensively sample the early-branching clades of this economically and ecologically important legume subfamily and thus to resolve relationships among them. • Methods: Parsimony and Bayesian phylogenetic analyses of the plastid matK and trnL intron sequences included 29 genera not yet sampled in matK phylogenies of the Papilionoideae, 11 of which were sampled for DNA sequence data for the first time. • Key results: The comprehensively sampled matK phylogeny better resolved the deep-branching relationships and increased support for many clades within Papilionoideae. The potentially earliest-branching papilionoid clade does not include any genus traditionally assigned to tribe Swartzieae. Dipterygeae is monophyletic with the inclusion of Monopteryx. The genera Aldina and Amphimas represent two of the nine main but as yet unresolved lineages comprising the large 50-kb inversion clade within papilionoids. The quinolizidine-alkaloid-accumulating genistoid clade is expanded to include a strongly supported subclade containing Ormosia and the previously unplaced Clathrotropis s.s., Panurea, and Spirotropis. Camoensia is the first-branching genus of the core genistoids. • Conclusions: The well-resolved phylogeny of the earliest-branching papilionoids generated in this study will greatly facilitate the efforts to redefine and stabilize the classification of this legume subfamily. Many key floral traits did not often predict phylogenetic relationships, so comparative studies on floral evolution and plant–animal interactions, for example, should also benefit from this study.  相似文献   

12.
Twenty‐two chromosome counts are reported in 16 species, four subspecies and two varieties of the genus Centaurea. These are mostly Turkish local endemics of section Cheirolepis, a complicated group from the Eastern clade of the Jacea group. Twenty‐one reports are new. Prevalence of the basic chromosome number x = 9 among the eastern sections of the Jacea group is confirmed. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 280–286.  相似文献   

13.
Boke , Norman H. (U. Oklahoma, Norman.) Anatomy and development in Solisia. Amer. Jour. Bot. 47(1): 59—65. Illus. 1960.–The genus Solisia contains a single species of small cacti which resemble certain mammillarias in having: pink, lateral flowers; milky juice; and dimorphic areoles. Adult specimens have elongate spiniferous areoles with an unusual sequence of spine initiation. The first four or five primordia appear at the posterior end of the areole meristem; the next are initiated near its center, after which initiation proceeds both acropetally and basipetally until the single, elliptical series of primordia is complete. A similar pattern of spine initiation occurs in Pelecyphora aselliformis, but this species differs markedly from S. pectinata in other respects. In seedlings of S. pectinata the areoles are broadly elliptical and spine initiation is strictly acropetal, a situation found in certain species of Mammillaria. Seeds of S. pectinata are black with a large hilum and a small perisperm. Since the perisperm has apparently been overlooked, it appears that only the black seed coat and relatively large hilum keep the species out of Mammillaria. If Buxbaum's postulates concerning the value of seed structure in tracing phylogeny in the Cactaceae are valid, S. pectinata must have diverged from the main line of evolution somewhere below Neobesseya. In that event, the species probably merits generic rank; otherwise, it seems preferable to return it to Mammillaria.  相似文献   

14.
This study aims to understand the role of floral traits in determining the reproductive biology of the leguminous shrub Aeschynomene amorphoides, endemic to western Mexico, which has unusually orientated flowers. We investigated the floral biology, pollination and breeding system based on a combination of morphological studies and field experiments, using controlled pollinations in a natural environment. The architecture and reflexed position of A. amorphoides flowers facilitate precise placement of pollen on the body of the pollinator, but this has a cost to A. amorphoides in terms of available flower resources. These costs to reproduction success are set against the attraction of a specialized pollinator, Tetraloniella jaliscoensis, which is capable of manipulating this unique pollination system in papilionoid (or flag) flowers. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2015, 177 , 657–666.  相似文献   

15.
A new species of Nepenthes L., N. attenboroughii (Nepenthaceae), from Palawan Island in the Philippines, is described and illustrated. It is restricted to rocky, ultramafic soils that comprise the summit region of Mount Victoria, Municipality of Narra, where it occurs in isolation from other members of the genus. On the basis of the morphological features, this new taxon appears to be related to both N. mira Jebb & Cheek of Palawan and N. rajah Hook.f. of Borneo. Its substantial size places it among the largest of known pitcher plants. The diagnostic morphological characters are discussed and an updated key is provided for a revised complex of Nepenthes species from the Palawan and North Borneo phytogeographical region. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 195–202.  相似文献   

16.
The cuticle micromorphology of the leaves of the monospecific genus Saxegothaea (Podocarpaceae) was studied by scanning electron microscopy. The external and internal features of the adaxial and abaxial surfaces were characterized. The leaves are hypostomatic. The external adaxial cuticle is rugose with irregular ridges and shallow trench‐like structures that do not correspond to any feature of the inner cuticle surface. The external abaxial cuticle has densely crowded stomata arranged in two bands. The stomata are sunken with pronounced, interrupted Florin rings. Stomatal plugs were not observed. Internally, the adaxial epidermal cells are usually rectangular to square; the abaxial epidermal cells are mainly restricted to the midrib and margins and narrowly rectangular; any among the stomata are irregularly shaped. The stomata are nearly all in direct contact. They show unusual features, including an extra pair of cuticular flanges between the guard cell flanges and those of the lateral subsidiary cells, and ‘bridges’ of lateral subsidiary cell tissue extending polewards above the polar extensions to unite with those at their tips. Neither of these features has been reported previously in Podocarpaceae. The results are discussed in the light of recent phylogenetic studies. It is concluded that, despite its unique cuticular features, Saxegothaea should continue to be regarded as a member of Podocarpaceae. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 58–67.  相似文献   

17.
Cottonseeds having fluorescent fibers were harvested from fields in Arizona and examined utilizing light microscopy and transmission electron microscopy. The occurrence of fluorescent fibers indicated that seeds had been infected by Aspergillus flavus during development. Presence of A. flavus was verified by plating portions of seeds with fluorescent fibers. Hyphae, conidial heads, and conidia were identified readily in differentially-stained cotyledon tissue processed for light microscopy. Utilization of transmission electron microscopy permitted observations on lignified seed coats and cotyledons of mature cottonseeds. Hyphae were located throughout the cotyledon and in the nonlignified layers of the seed coat. The identification of hyphae in cross sections of vessel elements within the seed coat provided ultrastructural evidence supporting the hypothesis that A. flavus may enter seeds via the vascular tissue. Controls for the microscopy studies included observations on cottonseeds with no visual signs of infection and on laboratory-grown cultures of A. flavus. These observations demonstrated that the hyphae localized within fluorescent seeds had features characteristic of A. flavus and that fungal-like structures do not occur within uninfected seeds.  相似文献   

18.
Previous work on orchid seeds has shown that characters associated with the seed coat may be useful for classification and phylogeny at a suprageneric level. The seed morphology of several species of the tribe Chloraeeae was analysed using traditional morphometrics, and the seed shape was studied, for the first time, using tools of geometric morphometrics. Seed characters were evaluated by their discriminative power and the information they may provide in a phylogenetic context. By contrast with previous findings, seed shape resulted in a continuum among the taxa studied, and in only a few cases could genera or groups of species be discriminated on the basis of shape. However, seed size, expressed as centroid size, was a variable character and informative at a phylogenetic level. Traditional measures of seed coat, mainly those of seed coat cells, were also helpful for the discrimination of genera and species, agreeing with previous statements about their utility in taxonomy and phylogeny. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 160 , 171–183.  相似文献   

19.
The nematomorph species Chordodes festae Camerano, 1897 and C. peraccae (Camerano, 1894) are redescribed by using scanning electron microscopy (SEM). C. festae has a cuticle with four different areolar types, the crown areoles being the most noticeable with long spiniform processes. The terminal end in the male specimen has two short lobe-like structures and a ventral groove. C. peraccae has three areolar types in which, as in C. festae, some areoles form groups surrounding the crown areoles. Intraspecific variations were found in body length and body colour in both species and, in C. peraccae, also in the cuticle.  相似文献   

20.
Triphorinae represents a group of three anatomically simple genera, the structural features of which are unspecialized. The anomocytic stomatal pattern occurs in all genera; it predominates in Triphora. A foliar hypodermis, sclerenchyma, fibre bundles and stegmata are absent. The mesophyll is homogeneous. The exodermal and endodermal cells in the roots are entirely thin‐walled and tilosomes are absent. However, there are anatomical modifications that appear to be unique: root hairs in Monophyllorchis are borne on velamenal buttresses and, in Psilochilus, they arise endogenously. In the root vascular system of Psilochilus, the metaxylem occurs as a circumferential band. The surfaces of stems in Triphora are tuberculate. Mycorrhizae appear to characterize the root cortices of all genera. © 2009 The Linnean Society of London, Botanical Journal of the Linnean Society, 2009, 159 , 203–210.  相似文献   

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