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1.
The wood of theSarraceniaceae has a considerable number of primitive features including scalariform perforation plates, long and oblique end walls, scalariform lateral wall pitting, solitary vessels, tracheids with scalariform pitting, and diffuse axial parenchyma. Vessel elements in the genusHeliamphora have the greatest number of primitive features, while vessel elements inDarlingtonia andSarracenia appear to have modifications relating to temperate climates. The wood anatomy suggests thatHeliamphora is growing in a habitat more similar to the original habitat for the family thanDarlingtonia andSarracenia. The wood of theSarraceniaceae is similar to the wood of theTheales.  相似文献   

2.
Most species of the neotropical genusSiphocampylus are believed to be bird-pollinated. The pollination biology ofSiphocampylus sulfureus was studied in a montane region in SE Brazil. This species has features intermediate between ornithophilous and chiropterophilous syndromes: it presents a striking combination of yellowish flowers with strong odour (chiropterophilous features), and diurnal anthesis and sucrose-dominated nectar (ornithophilous features). Major pollinators were hummingbirds by day, and a phyllostomid bat by night.Siphocampylus sulfureus may be viewed as a recent derivate from the presumed ornithophilous stock within sect.Macrosiphon, and thus benefits from the activity of both diurnal and nocturnal vertebrate pollinators.Dedicated to DrIlse Silberbauer-Gottsberger and Prof. DrGerhard Gottsberger for their pioneer contribution to floral biology in Brazil.  相似文献   

3.
Light and first SEM observations on the pollen ofAegialitis indicate that the two species of the genus are clearly distinguishable from all other genera of the tribeStaticeae to whichAegialitis presently is relegated. Intraspecific exine or aperture dimorphism which appears frequently in this tribe, is not recorded in this genus.A. annulata andA. rotundifolia have distinct monomorphic pollen and show a great resemblance in exine features with the tribePlumbagineae, particularly species ofPlumbago. Considering these and other features, separate subtribal status forAegialitis within thePlumbagineae is proposed.  相似文献   

4.
Comparative studies on floral morphology, anatomy, and histology were performed to identify shared features of the genera of Apodanthaceae (Rafflesiales): Apodanthes, Pilostyles, and Berlinianche. Berlinianche was studied for the first time in detail and its affinity to Apodanthaceae was confirmed. It has a previously undescribed hair cushion on the inner perianth organs and inaperturate pollen. Shared features of members of Apodanthaceae are: unisexual flowers; three (or four) alternating di-/tetra- or tri-/hexamerous whorls of scales of which the inner one or two correspond to a perianth; a synandrium with pollen sacs typically arranged in two rings; opening by a dehiscence line between the two rings of pollen sacs; large vesicular hairs above the synandrium; a gynoecium with four united carpels; inferior and unilocular ovaries with four parietal placentae, ovules tenuinucellate, anatropous with two well developed integuments, oriented in various directions; a nectary disk. Apodanthaceae share some special structural features with Malvales.  相似文献   

5.
The taxonomic status of three rarely captured, nominal species of Indo-Pacific symphurine tonguefishes,Symphurus trifasciatus (Alcock, 1894),S. microrhynchus (Weber, 1913), andS. holothuriae Chabanaud, 1948, is resolved.Symphurus microrhynchus, previously known only from three specimens, is redescribed based on 12 specimens.Symphurus holothuriae, previously reported only from the holotype, is a junior subjective synonym ofS. microrhynchus. Symphurus trifasciatus is redescribed based on six specimens, including the lectotype designated in this study.Symphurus microrhynchus is distinguished from congeners by a combination of meristic features, head and opercle shape, dorsalfin position, and features of its pigmentation. The species occurs in relatively shallow tropical waters from Zanzibar through French Polynesia (the only reported occurrence of a shallow-waterSymphurus from a locality on the Pacific Plate), including Indonesia, Papua New Guinea, Vietnam, and northwestern Australia.Symphurus trifasciatus, known from deep waters along both coasts of the Indian subcontinent and adjacent waters, has an overall similarity in body shape and meristic features reminiscent of those inS. microrhynchus, but differs notably in having a longer and wider head, a distinctive opercle shape, number of scale rows on the head, and pigmentation pattern.  相似文献   

6.
A detailed account of female reproductive features ofPlumariella yoshikawae is presented.Plumariella yoshikawae is recognized as morphologically similar toDelesseriopsis elegans in several features, particularly in the sequence of branch initiation, the presence of gland cells on the abaxial sides of the basal segments of the lateral branches, having carpogonial branches on the basal segments of unmodified lateral branches, and the maturation of the carposporophyte at well below the thallus apices. These features indicate thatPlumariella yoshikawae is best removed from the Ptiloteae and is correctly placed in the tribe Delesseriopsideae. The generaPlumariella andBalliella are retained along withDelesseriopsis within the tribe Delesseriopsideae.  相似文献   

7.
With the aim of making clear the boundaries between species in thePoa acroleucahisauchii-nipponica aggregate, chromosomes and morphological features of 746 collections gathered from 125 localities in Japan were examined. For morphological observations, the voucher specimens of 95 collections whose chromosome numbers were reported previously (Tateoka, 1985) were also used. Tetraploids (2n=28) and hexaploids (2n=42), as well as a few pentaploids which were the hybrids between 4× and 6×, were found. By examining morphological features of these collections, two groups were recognized in tetraploids and one in hexaploids. The two tetraploid groups corresponded toPoa acroleuca Steud. andP. hisauchii Honda, and the hexaploid group toP. nipponica Koidz. It was confirmed that the hairiness on the internerve surface of lemma, ligule hairiness and the length ratio of anther/ lemma are the most important features for discriminating between these species; panicle shape, leaf shape and anther length are also helpful for the identification. The ambiguity of the boundaries between species which was hitherto present in the taxonomy of this species aggregate was unrelated to the creation of nature itself but was attributable to the insufficiency of our research work.  相似文献   

8.
Comprida lagoon is a shallow lagoon separated from the sea by a sand barrier. It has a brown-coloured freshwater with a high concentration of humic compounds. Its zooplankton community and limnological features were studied from March 1992 to December 1995. The lagoon was characterized by low transparency, acid water and relative constant physical–chemical features, except during sporadic marine entrances. The zooplankton, composed of holoplanktonic and meroplanktonic forms, consisted of 60 taxa. Eleven were permanent elements of the community: e.g. Bosminopsis deitersi, nauplii and copepodites of `Diaptomus' azureus. B. deitersi correlated positively with the lowest pH values and with the highest total dissolved nitrogen. Only four taxa correlated with chlorophyll-a concentration. Pigmentation in `D.' azureus is suggested to be as an energy reserve in a system where phytoplankton is probably light-limited.  相似文献   

9.
The ear region of the pen-tailed treeshrew, Ptilocercus lowii Gray, 1848 (Scandentia, Ptilocercidae), is described and illustrated in detail based on five museum specimens from the National Museum of Natural History, two with the auditory bulla removed exposing the intratympanic surfaces. Soft tissues (arteries, veins, nerves, and muscles) are reconstructed onto the adult skulls based on published reports of these elements in a fetal P. lowii. Comparisons are made with four specimens of the common treeshrew, the tupaiid Tupaia glis (Diard, 1820), from the Carnegie Museum of Natural History, including one with the auditory bulla removed. The mammalian ear region widely is regarded to be a rich source of characters for phylogenetic analysis. This study supports this view by identifying numerous features that are shared between the two treeshrews as well as numerous features that distinguish them. Several features used in the past to distinguish tupaiid treeshrews from primates are found to differ between P. lowii and T. glis: the composition of the bony tubes for the internal carotid artery and the composition of the intrabullar septa and spaces. Despite the compositional differences, it seems likely that the bony carotid tubes and intrabullar septa and spaces shared by P. lowii and T. glis occurred in their common ancestor. Evaluating the utility of these and other ear region features awaits future phylogenetic analysis of treeshrews and related Euarchontoglires.  相似文献   

10.
We collected 24 brown rats, Rattus norvegicus, in Kanagawa Prefecture in Japan and found one rat harboring a dioctophymatid nematode. A single male and a female worm were recovered from the abdominal cavity and were identified as Dioctophyme renale based on morphologic features and a BLAST DNA sequence analysis. We describe the morphological features of the adult worms and eggs from this extremely rare case of D. renale infection in a brown rat.  相似文献   

11.
The morphology of an unarmored chain-forming harmful dinoflagellate Cochlodinium polykrikoides and its similar species such as Cochlodinium catenatum, Cochlodinium fulvescens, and Cochlodinium convolutum was carefully observed, emphasizing the single cell stage for clarifying taxonomically important morphological features. To differentiate C. polykrikoides from C. convolutum, the shape and the position of the nucleus are useful characters. C. polykrikoides also differs from C. fulvescens in being smaller in size, possessing many rod-shaped chloroplasts and having the sulcus running just below the cingulum on the dorsal surface. Careful observation of the ichnotype of C. catenatum suggests that C. catenatum sensu Kofoid and Swezy collected from off La Jolla, CA, USA, is not identical to C. catenatum sensu Okamura and is probably a different species, in having no chloroplasts and a nucleus positioned at the center of the cell. In addition, C. polykrikoides has many morphological features in common with C. catenatum sensu Okamura except for slightly elongate cells and is probably a junior synonym of this species.  相似文献   

12.
Identification of species within the boletoid genus Xerocomus has relied heavily upon the macromorphological features of the basidiomes. However, the phenotypic plasticity of these features has resulted in considerable confusion over the delimitation of taxa. In this study, we examined collections attributed to the X. subtomentosus complex in Europe using morphological and rDNA–ITS sequence data. In total, 45 European collections from a wide range of geographical areas and ecological conditions were included in the study. In spite of detecting considerable genetic variation, even within individual basidiomes of X. subtomentosus, molecular data, spore size, flesh colour, and the colour of the basal mycelium allow for the recognition of four distinct taxa: two correspond to X. subtomentosus (13 collections) and X. ferrugineus (20); one X. chrysonemus sp. nov. (10), to date only found in the UK, is described as new; and the existence of another taxon (two; Italy and UK) is noted but left undescribed owing to lack of material. Eight collections from North America were also included in the study, from which two taxa with a close affinity to X. ferrugineus were recognised.  相似文献   

13.
Two of the five species ofOliniaceae (Olinia emarginata andO. ventosa), a monotypic and problematic family of theMyrtales, were investigated embryologically.Oliniaceae clearly agree with otherMyrtales in their basic embryological characteristics, and are characterized further by having an ephemeral endothecium, a campylotropous ovule, and a thick, three-five-layered, outer integument. A combination of these three characteristic features is unknown elsewhere inMyrtales, so that embryological features do not support a close relationship with any other member of the order. Shared distinctive anther characteristics (i.e. ephemeral endothecium) suggest thatOliniaceae are derived from the common ancestor ofCrypteroniaceae s. str.,Rhynchocalycaceae, Alzateaceae, andPenaeaceae.  相似文献   

14.
The fine structure of the type species of the genusCyanothece Komárek 1976,C. aeruginosa, is described and compared with the main cytological characteristics of morphologically related members of the generaCyanobium, Cyanobacterium andSynechococcus. Several morphological features, such as cell walls with thick outer layers containing a special type of vesicles, position of thylakoids, keritomy (net-like appearance of protoplast caused by arrangement of thylakoids, net-like nucleoids and/or by tendency to form intrathylakoidal spaces) and a special structure of mucilaginous envelopes were found to be characteristic of this genus, supporting its separate position among coccal cyanoprokaryotes (cyanobacteria, cyanophytes). The taxonomic significance of ultrastructural features in all mentioned genera is discussed.  相似文献   

15.
蒋天翼  陈志钊  陈曌  郑永利  陈昕  邓云飞 《广西植物》2023,43(10):1814-1827
为澄清映山红亚属(Rhododendron subg. Tsutsusi)内的系统关系问题,该研究选择杜鹃花属映山红亚属37种植物作为对象,其中29种为首次报道,通过扫描电镜观察其叶表皮显微特征。结果表明:(1)气孔器均为无规则型且均在远轴面。(2)根据叶片微形态特征将映山红亚属的种类分为杜鹃型(R. simisii-type)、岭南杜鹃型(R. mariae-type)、皋月杜鹃型(R. indicum-type)、崖壁杜鹃型(R. saxatile-type)及丁香杜鹃型(R. farrerae-type)5种类型。(3)杜鹃型植物的气孔器周边无或具间断的条形突起。(4)岭南杜鹃型植物的气孔器周围有多层条形突起环绕,保卫细胞两极不具T型加厚。(5)皋月杜鹃型植物的叶表皮保卫细胞两极具有T型加厚,与叶状苞亚属(Subg. Therorhodion)叶状苞杜鹃(R. redowskianum)的气孔器特征相似,推测其与叶状苞亚属具有一定的亲缘关系。(6)崖壁杜鹃型植物的叶表皮毛单一,多呈卷曲状,与其他类型有所不同且未见腺体。(7)丁香杜鹃型植物的叶表皮仅有腺体。(8)依据叶表皮微形态特征讨论了一些近缘种类的关系,如倾向于将背绒杜鹃(R. hypoblematosum)和千针叶杜鹃(R. polyraphidoideum)处理为独立的种,支持保留紫薇春(R. naamkwanense var. cryptonerve)作为南昆杜鹃(R. naamkwanense)的变种地位,不支持将腺花杜鹃(R. adenanthum)并入细瘦杜鹃(R. tenue)作异名处理等。该研究结果表明叶表皮显微特征在映山红亚属内物种划分上具有重要价值。  相似文献   

16.
The diploid chromosome number for the EuropeanLinum hologynum and the haploid number for the AustralianL. monogynum is 42 and appears to establish a new and distinctive base number for sect.Linum. The possession by these two species and by the AustralianL. marginale of multiporate pollen and united styles, a unique combination of features in sect.Linum, may warrant the establishment of a new subsection in that section to accommodate the three species.  相似文献   

17.
In this paper we present the first results concerning the embryology of Chrysobalanaceae. In it, we document developmental features of anthers, ovules, seeds and gametophytes ofChrysobalanus andLicania (tribe Chrysobalaneae). Based on our results with these two genera, Chrysobalanaceae have a distinctive combination of embryological features. They differ from Rosaceae (in which Chrysobalanaceae were once placed as a tribe or subfamily) in having a tenuinucellate ovule, a small nucellus with the tissue soon disintegrating, and an endothelium. None of our embryological of Rosales, or with other groups such as Fabaceae or Myrtales, which have also been suggested as relatives. We propose, based upon the evidence from embryology, vegetative features, and reproductive morphology, that Chrysobalanaceae might best be placed in the order Theales, probably near the family Theaceae.  相似文献   

18.
Summary The euglenoids and kinetoplastids form a diverse assemblage of organisms which show no obvious phylogenetic relationship with other flagellates. An ultrastructural examination and comparison of the flagellar apparatus, the feeding apparatus, and mitotic nucleus indicate a number of shared morphological features which support a common ancestry for the two groups. Of particular interest is the euglenoid,Petalomonas cantuscygni, which shares many of the ultrastructural features common to both groups. Based on the data presented, we hypothesize that a euglenoid with features similar to those now present inP. cantuscygni was ancestral to both the euglenoid and kinetoplastid lines.Abbrevation MTR complex of reinforcing microtubules  相似文献   

19.
Karyotype and external morphological analyses were conducted onMedicago ciliaris, M. intertexta, M. muricoleptis andM. granadensis which comprise theIntertextae section of the genusMedicago. All species were found to have 2n = 16 chromosomes (= 2 ×), including one pair of satellite chromosomes in each respective complement. Karyotypic evolution in theIntertextae involves changes in absolute chromosome size and in centromeric and relative size symmetry. Numerical taxonomic analyses were conducted independently on 17 karyotypic features and on 16 features of external morphology. The results of the two sets of analyses proved comparable, withM. ciliaris andM. intertexta forming a fairly close pair, and the remaining two species appearing to have more distant relationships to each other and to the first pair. These observations are consistent with the infertility relationships and chorologies of the species. It is suggested thatM. muricoleptis andM. granadensis are derived from theM. ciliaris/intertexta species complex withM. granadensis arising fromM. muricoleptis, or these two species independently evolving from a common species complex. Chromosomal and numerical analyses suggest thatM. ciliaris is the most primitive andM. granadensis the most derived species of theIntertextae.  相似文献   

20.
Paleobiology of the oligopithecines,the earliest known anthropoid primates   总被引:1,自引:0,他引:1  
Anthropoid primates of the subfamily Oligopithecinae are late Eocene in age, and have a known distribution of Northeast Africa and the Arabian Peninsula. Body sizes of the three known oligopithecine species are estimated from allometric molar size regressions to be 700–1000 g forOligopithecus savagei, 600–900 g forCatopithecus browni, and 500 g for the least well-known and smallest species,Proteopithecus sylviae. Occlusal features of the molar teeth, considered in conjunction with body size, suggest that all three species were frugivorous and insectivorous. The orbital size ofCatopithecus indicates a diurnal activity cycle. A relatively broad interobital region in this species may indicate prosimian-like or callitrichid-like olfactory adaptations. Structural features of the crushed skull suggest thatCatopithecus had a smaller cranial capacity than those of extant anthropoids with a similar body size. Fossil plants and birds from localities yielding oligopithecines suggest a wet, warm, tropical, forested, swampy environment. These paleobiological inferences about the extinct oligopithecines are discussed in relation to questions about primate adaptations near the prosimian-anthropoid transition.  相似文献   

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