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1.
 The fruit and seed anatomy and morphology of the two genera Bersama and Melianthus (Melianthaceae, Sapindales) have been studied in an effort to clarify their systematic position. On the basis of the differences in pericarp and seed anatomy as well as in other exomorphic characters the segregation of Bersama into a distinct family Bersamaceae is supported. Evidence mainly from seed anatomy and morphology emphasizes the anomaly of the traditional inclusion of Bersama and Melianthus in the Sapindales, since they have a distinct seed-coat structure and seed vascularization. The fruit and seed anatomy does not confirm any relationships with alternatively suggested exo-mesotestal Lardizabalaceae. The exotestal seed coats of Bersama and Melianthus with a differentiated palisade of Malpighian cells in the exotesta, dimerous raphal vascular skeleton, abundant endosperm, and a small differentiated straight embryo show a resemblance with the exotestal albuminous seeds of Rhamnaceae and Elaeagnaceae. Using also additional data on fruit, floral and vegetative morphology it is suggested that Bersamaceae with Melianthaceae and Rhamnaceae/Elaeagnaceae constitute a distinct relict side-branch of exo-mesotestal rosidaceous ancestry, the new order Melianthales in the superorder Rhamnanae (Rosidae). The formerly suggested relationship of this side-branch to exotegmic Malvales is not supported by seed anatomy. The affinity with exotegmic Celastrales, which are considered as a possible connecting link between archaic exo-mesotestal Rosales and exotestal Rhamnales/Elaeagnales, is also found untenable. Received May 12, 2000 Accepted December 7, 2000  相似文献   

2.
A morphological and anatomical study of fruits and seeds often species ofVerbascumfrom south-west Spain has been made.The seeds showed considerable uniformity in shape, size, seed-coatornamentation and internal structure. Two groups of speciesare distinguished on the basis of indumentum of the capsules.The first group has branched hairs which do not appear in thesecond. Only one species,V. virgatummay be included in bothgroups. Other characters such as corolla size or stamen number,support separation of both groups and reaffirm the intermediateposition ofV. virgatum. A key to distinguish the taxa is provided.Copyright1997 Annals of Botany Company Pericarp; seed-coat; SEM; anatomy  相似文献   

3.
The delimitation of Bignoniaceae and Scrophulariaceae has long been a taxonomic problem. Several genera, including Paulownia, Schlegelia, Gibsoniothamnus, and Synapsis, have been variously placed in one or the other family. Differences between these two families have been noted with regard to the presence of endosperm, embryo and seed morphology, and placentation; however, the lack of comprehensive data on the distribution of such characters within these two families left the delimitation problem unsolved. A comprehensive study of floral anatomy confirmed a basic difference in the placentation of these two families, as well as a basic difference in gynoecial vascularization. Paulownia has a floral anatomy, embryo morphology, and seed morphology consistent with placement in Scrophulariaceae. While reminiscent of Bignoniaceae, Paulownia is not an intermediate genus linking the two families. Schlegelia and Gibsoniothamnus have a floral anatomy consistent with placement in Scrophulariaceae. Schlegelia also has a scrophulariaceous seed morphology. Considered anomalous in the Bignoniaceae, the Schlegelieae similarly are distinct in the Scrophulariaceae.  相似文献   

4.
Phenetic and cladistic relationships among tenebrionid beetles (Coleoptera)   总被引:4,自引:0,他引:4  
Abstract. The higher classification of Tenebrionidae is analysed using numerical phenetic, numerical cladistic and traditional Hennigian methods. In all, eighty characters are examined for about 335 taxa; definitive analyses are made on combinations of eighteen to seventy characters for thirty-three OTUs. At lower levels of relationship (genera and closely related tribes) phenetic and cladistic classifications are shown to be congruent, but at higher levels (tribes and subfamilies) there is marked discordance with phenetic results being more stable. A consensus classification is more similar to the Hennigian cladogram than is any single computer generated cladogram. Two main tribal groups – the Lagrioid and Tenebrionoid groups – are suggested which differ in defensive glands, female anatomy, wing and mouthpart morphology, larval characters and other features. The Tenebrionoid group consists of three main subdivisions – the tenebrionine, coelometopine and diaperine lineages. Changes in classificatory position are recommended for eighty-seven genera and tribes (listed in Appendix E) and implied for numerous others.  相似文献   

5.
Seed structure and the taxonomy of the Cruciferae   总被引:5,自引:0,他引:5  
The external morphology and anatomy of the seeds of some 90 genera and some 200 species of the Cruciferae have been investigated. Emphasis has been laid on the relationships of seed structure to taxonomy. As regards seed anatomy, the testa is probably of greatest value in determining taxonomic relationships. Seed structure supports the Cruciferae as a natural taxon. In the present investigation, few genera and species show seed characters which are either exclusive or very distinct. Of the remainder, most genera are distinguishable from each other on a permutation of their macroscopic and microscopic seed characters. However it is difficult or impossible to distinguish between some genera on seed characters. The present investigation provides no support for tribal divisions within the Cruciferae.  相似文献   

6.
7.
The Elysiidae is the largest family of Sacoglossa (=Ascoglossa)(Mollusca, Opisthobranchia). The Indo-Pacific fauna containsabout 65 species presently referred to the genus Elysia. Almostnothing is known about the internal anatomy of these animals.In the present study the internal anatomy, particularly thepharyngeal musculature, morphology of radularteeth, and reproductivesystems, of 12 Indo-Pacific elysiids is investigated. Also,the internal anatomy of the Mediterranean type species of thegenera Elysia and Thuridilla is described. On this basis, thevalidity of the genera Elysia, Thuridilla, Elysiella and Pattyclaya,is confirmed. Also, the genus Placobranchus is transferred tothe Elysiidae. phylogenetically important characters are identifiedand phylogenetic relationships within the family are discussed. (Received 10 April 1991; accepted 28 December 1991)  相似文献   

8.
The surface features of the seed of the parasitic floweringplant Striga hermonthica were examined with the scanning electronmicroscope. The details of ornamentation were constant on seedsfrom one plant but varied within and between populations andare probably due to out-breeding. The variation was not relatedto geographical origin or to host-preference. Testa patternssimilar to those reported for other Striga species were foundin the samples. Striga hermonthica, Scrophulariaceae: Rhinanthoideae, hemi-parasite, testa, seed-coat, scanning electron microscope, genetic variation  相似文献   

9.
Seeds of 24 taxa of Linaria from south-west Spain were examinedwith a scanning electron microscope and light microscope. Basedon seed features such as shape, surface ornamentation and cellshape, seven morphological types were recognized. Seeds of thedifferent types are described, illustrated and compared. A keyto distinguish the different species or groups of species isprovided. Copyright 1999 Annals of Botany Company Seed-coat, SEM, anatomy, Scrophulariaceae, Antirrhineae, Linaria .  相似文献   

10.
Studied in this work was seed morphology of the genus Plantago (2 subgenera, 8 sections, 17 species and 1 variety )in China. The sculpture was observed under scanning election microscope. Four forms of seed morphology are recognized as follows: (1)Multi-angular type: seeds are variously angulate, yellow-brown or black, 6-30 in a fruit; seed-coat sculpture ranges from reticulate to papillate. It occurs in Subgen. Plantago Sect. Polyneuron: P. scheideri, P. denstflorus, P. major, P. hostifolia, P. asiatica, P. erosa and P. centralis. (2) Navicular type: seeds are navicular, yellow, brown to black, 2 in a fruit; seed-coat sculpture is reticulate. It was found in Subgen. Plantago Sect. Novorbis: P. virginica; Sect. Arnoglossum: P. lanceolata; Sect. Leucopsyllium: P. minuta, P. lessingii and P. aristata and Subgen. Psyllium Sect. Psyllium: P. indica. (3)Ovoid type: seeds are long-ovoid, yellow-brown, black and lustrous. Seed-coat sculpture scali-ratiform. P. maxima in Subgen. Plantago Sect. Lamprosantha belongs to this type. (4)Recti-circular type: seeds are recti-circular, yellow-brown, black, 1-2 or 4-5 in a fruit; seed-coat sculpture is reticulate and papillate. It was found in P. maritima var. salsa of Subgen. Plantago Sect. Coronopus and P. depressa, P. camtschatica and P. arachnoidea of Sect. Mesembrynia. The seed morphology and seed-coat sculture exhibit specific characters, by which some of confused species can be clarified and a new species, P. densiflorus J. Z. Liu. is established. The present author’s seed morphology classification is in accordance with Pilger’s systemof the genus, which was established using other features.  相似文献   

11.
Development and structure of seed-coat were examined in 16 species ofCorydalis and two species ofDicentra. Neither the tegmen (developed ii) nor the testa (developed oi) is multiplicative during seed development. Mature seed-coat is consistent in all the species examined in having mechanical structure in the exo- or endotesta. Differences are found in (1) which of the integumentary layers develops into the main mechanical layer (exotesta or endotesta), (2) whether a mesotesta is differentiated or not, and (3) whether the endotegmen is persistent as a layer of thick-walled cells, is persistent only partially, or is thoroughly degenerated. Theses seed-coat characters distinguish six groups of species (i.e., four groups inCorydalis and two inDicentra), which represent well infrageneric taxa proposed on the other characters. Evidence from seed-coat anatomy further suggests thatDicentra spectabilis (subg.Hedycapnos) retains the primitive (endotestal) seed-coat of Fumarioideae.  相似文献   

12.
Gynoecium, fruit and seed structure of Paullinieae (Sapindaceae)   总被引:1,自引:0,他引:1  
Despite an emphasis on fruit characters in Paullinieae taxonomy, few detailed morphological and anatomical studies of the gynoecia, fruits and seeds exist. The aims of the present study were (1) to provide a detailed documentation of gynoecium, fruit and seed structure and ontogeny in selected Paullinieae taxa; (2) to determine whether the gynoecium, seed and seedling provide additional characters of systematic value within the tribe; and (3) to relate the structural findings to mechanisms of fruit dehiscence and dispersal within these taxa. Newly described characters of systematic value within Paullinieae are shape and surface of the obturator, type of pollen tube transmitting tract, indumentum of the inner and outer surface of the carpels, ovary wall anatomy, aril anatomy, pseudo-hilum form, seedling germination mode and structure of first leaves. The fruits of Paullinia are septifragal, and conspicuous colour contrasts between the pericarp, aril and seed in most species of this genus are suggestive of a bird dispersal syndrome. Interestingly, it appears that relatively minor structural changes are associated with switches to rodent dispersal in Paullinia sphaerocarpa and water dispersal in P. clathrata and P. hystrix. Anemochorous fruits are septifragal ( Cardiospermum and Urvillea ) or schizocarpic ( Houssayanthus , Lophostigma , Serjania ). They are structurally similar and Cardiospermum with septifragal capsules may also show septicidal dehiscence.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 147 , 159–189.  相似文献   

13.
The fruit and seed anatomy and morphology ofGalbulimima belgraveana(F.Muell.) Sprague, a solitary species of the monotypic genus inthe Himantandraceae, have been studied in an effort to clarifyits systematic position. The indehiscent fleshy multicarpellary,two- or three-ranked capsetum ofGalbulimimaconsists of follicles(capseoles) with lignified fibrous five- or six-layered endocarp.Such construction of the himantandraceous capsetum suggestsderivation from free cone-like fruits similar to those of Annonaceaeand Magnoliaceae. Seeds ofGalbulimimaare relatively large, flattened,winged, with a solitary vascular bundle extending to the micropyle,and a cup of hypostase. They are abundantly albuminous and havea small dicotyledonous embryo. The seed coat ofGalbulimimaismesotestal with testal-tegmic ruminations and unspecializedtwo- or three-layered tegmen; a single-layered exotesta representedby thin-walled tanniniferous cells; a two (–three)-layeredmesotesta, composed of thick-walled lignified longitudinal fibres;and an endotesta composed of two or three layers of unspecializedaerenchymatous parenchyma. Evidence, mainly from seed morphologyand anatomy of seed coats, emphasizes the anomaly of the traditionalaffiliation of Himantandraceae with MagnolialessensuTakhtajan,being quite distinct in spermoderm structure and origin fromboth Magnoliaceae and Degeneriaceae in particular. Furthermore,seed anatomy does not confirm any relationships with Myristicaceaeor Canellaceae. Among all Magnoliidae, the structure of theseed coats ofGalbulimimais similar to that of some advancedAnnonaceae and Eupomatiaceae. It is suggested that Himantandraceaetogether with Eupomatiaceae and Annonaceae constitute a distinctrelic blind branch of magnoliid ancestry. On the basis of availabledata of seed coat anatomy, it is appropriate to remove Himantandralesfrom the order Magnolialessensu stricto, and to place it intoits own monotypic order, Himantandralesord. nov.,grouping togetherwith orders Eupomatiales and Annonales in Magnoliidae.Copyright1998 Annals of Botany Company Galbulimima belgraveana(F. Muell.) Sprague; carpology; pericarp; seed anatomy; systematics; phylogenetic relationships; Himantandraceae; Magnoliaceae; Eupomatiaceae; Degeneriaceae; Annonaceae; Liriodendraceae; Myristicaceae; Canellaceae.  相似文献   

14.
A comparative carpological study of 96 species of all clades formerly considered as the tribe Chenopodieae has been conducted for the first time. The results show important differences in the anatomical structure of the pericarp and seed coat between representatives of terminal clades including Chenopodium s.str.+Chenopodiastrum and the recently recognized genera Blitum, Oxybasis and Dysphania. Within Chenopodium the most significant changes in fruit and seed structure are found in members of C. sect. Skottsbergia. The genera Rhagodia and Einadia differ insignificantly from Chenopodium. The evolution of heterospermy in Chenopodium is discussed. Almost all representatives of the tribe Dysphanieae are clearly separated from other Chenopodioideae on the basis of a diverse set of characteristics, including the small dimensions of the fruits (especially in Australian taxa), their subglobose shape (excl. Teloxys and Suckleya), and peculiarities of the pericarp indumentum. The set of fruit and seed characters evolved within the subfamily Chenopodioideae is described. A recent phylogenetic hypothesis is employed to examine the evolution of three (out of a total of 21) characters, namely seed color, testa-cell protoplast characteristics and embryo orientation.  相似文献   

15.
Fruit characteristics, embryo types, and funicle-aril features are described for the genera of neotropical Lecythidaceae. Their bearing on the taxonomy of the family is discussed and a generic key based on fruit and seed features is provided. The anomalous seed structure ofAsteranthos brasiliensis is pointed out. Known fruit and seed adaptations for dispersal are described.  相似文献   

16.
This study shows that structural data, when carefully examined, can provide valuable characters for delimiting monophyletic groups and can complement DNA with observable features to recognize and circumscribe taxa. In the angiosperm order Apiales, traditional classification has relied heavily (often exclusively) on fruit characters. Recent molecular systematic studies, however, provided a radically different picture of relationships, calling into question the utility of fruit characters. We have studied fruit anatomy from 18 genera (Annesorhiza, Asteriscium, Astrotricha, Choritaenia, Dasispermum, Elaeoselinum, Heptaptera, Hermas, Heteromorpha, Laretia, Molopospermum, Myodocarpus, Pachypleurum, Peucedanum, Polemanniopsis, Polylophium, Rouya, and Tordylium) that represent all major taxonomic groups of Apiales characterized by winged fruits and the full range of wing types. Fruit anatomy closely corresponded with the phylogenetic position of these genera, as suggested by molecular studies. Fruit features of taxonomic importance include developmental origin of the wings, carpel shape, presence of vittae, woodiness of the endocarp, position of crystals, and type of carpophores. Despite the long history of recognizing umbellifers as a "natural group," few studies have been able to provide structural characters to help circumscribe the clades identified by molecular data. The interpretations presented are an important step toward erecting a stable system of classification for this difficult family.  相似文献   

17.
Morphological characteristics were studied in two groups ofclosely related taxa of sectionSupinae , Linaria depauperataand L. supina, from eastern Spain. Vegetative, floral and seedcharacteristics were of little use in distinguishing betweenthese taxa as the ranges for all the taxa studied overlapped.Flower colour could be used as a diagnostic character for somebut not all of these taxa. Seed coat characters were of hightaxonomic value, both when trying to distinguish among thesetwo groups, and the taxa included within them, and also whenestablishing relationships among the taxa studied. Some differenceswere found in the indumentum distribution and density. Threetypes of trichomes were identified, two of them eglandular andcommon to all taxa. The third type of trichome was a simplegland, that varied in the number of cells in the stalk and gland.Trichome length and wall width of stalk cells allowed severalgroups of taxa to be distinguished. Similarity relationshipsamong the samples studied are shown in a UPGMA phenogram. Accordingto these results, two new species, L. cardonica and L. sulphurea,are described. L. arabiniana is conspecific with L. depauperatasubsp. hegelmaieri. A key to identify the different taxa isprovided. Copyright 2001 Annals of Botany Company Scropulariaceae, Antirrhineae, taxonomy, morphological characters, seed-coat, trichomes, Linaria depauperata,Linaria supina  相似文献   

18.
Embryology allows one to work with a wide array of characters (more than 50 in general) for each taxon of angiosperms. This paper, while providing a brief review of recent studies on Myrtales and associated families by me and my co-workers, discusses evidence for the general utility of embryological characters for the study of plant systematics. In particular, evidence is given that characters of seed coat anatomy may be best applied to the study of specific and sectional (and even familial) relationships, those of seed appendages as well as of integumentary morphology and histogenesis to the study of generic relationships, and other major characters to the study of familial relationships. Embryology thus provides many features that are complex and, when properly applied along with evidence from other sources, offers good indications of relationships at various taxonomic level, from the ordinal to the specific level. Despite its evident systematic value and increasing need, however, information on embryological characters is still lacking for a majority of genera, and even at the family level, data is lacking or insufficiently available for more than 30% of families. Recipient of the Botanical Society Award for Young Scientists, 1987.  相似文献   

19.
Scanning electron microscopic investigations of seed morphology of the five genera of Menyanthaceae illustrate a remarkable diversity of seed characteristics for a small family. Seeds of the monotypic northern hemisphere Menyanthes and Fauria are unomamented and similar, and those of the monotypic Liparophyllum of New Zealand and Tasmania are similar to some Australian species of Villarsia. Seed characteristics within the larger genera Villarsia and Nymphoides are variable and mostly species specific, but do not lend support to taxonomic separation of these genera. Interspecific affinities postulated on other grounds are, in many instances, supported by seed morphology. Various seed-coat features are believed to aid in water or animal dispersal of the seeds of several species. Ant dispersal appears to be important for Villarsia and Nymphoides in Australia, but does not seem to occur in these genera or in other members of the family outside of Australia.  相似文献   

20.
To analyse the status and phylogeny of the genusPhyllocladus,seedsof all seven species of the genus were studied. The complexof features of thePhyllocladusreproductive system point to theisolated position of the genus within the conifers. Relationswith Podocarpaceae s. l., Taxaceae s. l. and Cephalotaxaceaeappeared to be remote because a complex of features clearlydistinguishesPhyllocladusfrom the afore-mentioned taxa. We findit advisable to circumscribe the family Phyllocladaceae as Bessey(1907) did, and place it into the order Taxales Knobl. in Warming(1890). From investigations of the seeds it appears the genusPhyllocladusconsistsof seven species, forming five groups. There is a significanttendency for transformation of the female reproductive structureswithin the generic boundaries ofPhyllocladus—seeds, originallysolitary, tending to aggregate in various kinds of compact clusters.Copyright1999 Annals of Botany Company PhyllocladusL. C. & A. Rich, ex Mirb., seed anatomy, seed morphology, systematics, phylogenetic relationships, Phyllocladaceae, Podocarpaceae s. str., Acmopyleaceae, Nageiaceae, Austrotaxaceae, Amentotaxaceae, Torreyaceae, Taxaceae, s. str., Cephalotaxaceae, Taxales.  相似文献   

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