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1.
Some examples of association between platanoid leaves and various reproductive structures are considered. The expediency of determining dispersed Cretaceous platanoid leaves using a morphological system that is independent of the system of modern plants is discussed. It is confirmed that leaf structures are more conservative than reproductive organs. It is proposed that, in the geological past, there was a polymorphic group that was probably represented by extinct families which gave rise to modern families (in particular, Platanaceae and Hamamelidaceae).  相似文献   

2.
3.
The rbcL gene sequences of six species representing five subfamilies of the Hamamelidaceae and the Platanaceae were determined and used in the phylogenetic analysis on the “lower” Hamamelidae sensu Endress (1989) and its allies newly suggested. Four most parsimonious trees were obtained, all having 893 steps with CI = 0.558 and RI = 0.591. The families Cercidiphyllaceae, Daphniphyllaceae, Hamamelidaceae and Saxifragaceae are closely located, while the relationships among them remain unsolved even if more representatives of the Hamamelidaceae were further added in this parsimony analysis. Our results confirm the phylogenetic trees revealed by Chase et al. (1993) and Soltis et al. (1997), instead of those of Hoot and Crane (1996). Considering the morphological features they share, it is suggested that the Cercidiphyllaceae and Daphniphyllaceae be placed into the Hamamelidales. The relationship between the Platanaceae and the Hamamelidaceae shown in our analysis is not so closed as suggested by the cladistic analyses by using morphological characters only(e.g. Lu et al., 1991), while those among the Platanaceae, Trochodendraceae and Tetracentraceae are close as indicated by this study. The Eupteleaceae falls into the Ranunculales. The Eucommiaceae seems to show closer relationship with the Hamamelidaceae, the “core” family of the “lower” Hamamelidae, than with the other members except the Cercidiphyllaceae. The rbcL gene trees imply that the “lower” Hamamelidae is a heterogeneous group,composed of isolated ancient families.  相似文献   

4.
A cladistic analysis of the families in the Hamamelidae is made in the present paper. As a monophyletic group, the subclass Hamamelidae includes 19 families, namely, the Trochodendraceae, Tetracentraceae, Cercidiphyllaceae, Eupteleaceae, Eucommiaceae, Hamamelidaceae (incl. Rhodoleiaceae and Altingiaceae), Platanaceae, Daphniphyllaceae, Balanopaceae, Didymelaceae, Myrothamnaceae, Buxaceae, Simmondsiaceae, Casuarinaceae, Fagaceae (incl. Nothofagaceae), Betulaceae, Myricaceae, Rhoipteleaceae and Juglandaceae. The Magnoliaceae was selected for outgroup comparison after careful consideration. Thirty-two informative character states were used in this study. Three principles, namely, outgroup comparison, fossil evidence and generally accepted viewpoints of morphological evolution, were used for polarization of the characters. An incompatible number concept was first introduced to evaluate the reliable degree of polarization of the characters and, by this method, the polarization of the three character states was corrected. A data matrix was constructed by the 19 ingroup families and 32 character states. The data matrix was analysed with the Minimal Parallel Evolutionary Method, Maximal Same Step Method (Xu 1989), and Synthetic Method. Three cladograms were constructed and a parsimonious cladogram (Length= 131)was used as the base for discussing the systematic relationships of families in the Hamamelidae. According to the cladogram, the earlist group differented in the subclass Hamamelidae consists of two vesselless wood families, the Trochodendraceae and Tetracentraceae. This result supports the concept proposed by Takhtajan (1987)and Cronquist (1981, 1988)that the Trochodendrales is probably a primitive taxon in the Hamamelidae. As in a clade group, the Cercidiphyllaceae, Eucommiaceae, Balanopaceae and Didymelaceae originated apparently later than the Trochodendrales. The Cercidiphyllaceae diverged earlier in this group, which implies that this family and the Trochodendrales form a primitive group in the subclass. The Cercidiphyllaceae is either placed in Hamamelidales (Cronquist 1981, Thorne 1983), or treated as an independent order (Takhtajan 1987).This analysis suggests that the Cercidiphyllaceae is a relatively isolated taxon, far from the Hamamelidaceae but close to the Trochodendrales in relation. The Eucommiaceae and Didymelaceae are both isolated families and considered as two distinct orders (Takhtajan 1987, Cronquist 1981, 1988).The Balanopaceae is included in the Fagales (Cronquist 1981, 1988) or Pittosporales (Thorne 1983), or treated as a distinct order Balanopales (Takhtajan 1987 ).Obviously the Balanopaceae and Eucommiaceae are not closely related because of the sole synapomorphy (placentation).In fact these four families are more or less isolated taxa and it is probably more reasonable to treat them as independent orders. Cronquist ( 1981, 1988) places the Eupteleaceae, Platanaceae and Myrothamnaceae in the Hamamelidales, while Takhtajan (1987)puts Hamamelidaceae and Platanaceae into the Hamamelidales and treats the Eupteleaceae and Myrothamnaceae as two independent monofamilial orders. These three families are grouped by more synapomorphies (palmateveined, serrate or lobate leaves, deciduous and anemophilous plants)which may indicate their close phylogenetical affinity. A core group of the Hamamelidae includes ten families, among which the Hamamelidaceae originated earlier than the others, so that it is a relatively primitive family. The Betulaceae, Fagaceae and Myricaceae differentiated later than the Hamamelidaceae. The former two are very closely related, and thus thought to be two neighbouring orders by Takhtajan (1987)or included in the Fagales by Cronquist (1981, 1988)and Thorne (1983). The Myricaceae and Fagaceae are connected in the cladogram by only a single synapomorphy (endosperm absent), and therefore the close relationship does not exist between them. The Buxaceae, Simmondsiaceae and Daphniphyllaceae form an advanced group, in which they are weakly linked with each other by only one synapomorphy (pollen grains<25μm). The Daphniphyllaceae is closely related to the Simmondsiaceae, but the Buxaceae is rather isolated. The Rhoipteleaceae and Juglandaceae share a number of synapomorphies (axile placentation, endosperm absent, embryo larger, fruit indehiscent) , forming a highly specialized group. The opinion that the Juglandales is composed of the Juglandaceae and Rhoipteleaceae(Cronquist 1981; 1988, Lu et Zhang 1990)is confirmed by this analysis. A contrary point of view, which treated them as two distinct orders by Takhtajan (1987), apparently could not be accepted. The Casuarinaceae was regarded as the primitive angiosperm (Engler 1893), but in fact it is a highly reduced and specialized group. It is united with Rhoipteleaceae and Juglandaceae by four synapomorphies, i. e. placentation type, endosperm absent, embryo large and fruit indehiscent. However, the family presents six autapomorphies, and thus the position of the Casuarinaceae as an advanced family is confirmed by this analysis. Finally a strict consensus tree, which represents the phylogenetic relationships of thefamilies in the Hamamelidae, was given as a result of the analysis.  相似文献   

5.
Gynoecium diversity and systematics of the basal eudicots   总被引:6,自引:0,他引:6  
Gynoecium and ovule structure was compared in representatives of the basal eudicots, including Ranunculales (Berberidaceae, Circaeasteraceae, Eupteleaceae, Lardizabalaceae, Menispermaceae, Papaveraceae, Ranunculaceae), Proteales (Nelumbonaceae, Platanaceae, Proteaceae), some families of the former ‘lower’ hamamelids that have been moved to Saxifragales (Altingiaceae, Cercidiphyllaceae, Daphniphyllaceae, Hamamelidaceae), and some families of uncertain position (Gunneraceae, Myrothamnaceae, Buxaceae, Sabiaceae, Trochodendraceae). In all representatives studied, the carpels (or syncarpous gynoecia) are closed at anthesis. This closure is attained in different ways: (1) by secretion without postgenital fusion (Berberidaceae, Papaveraceae, Nelumbonaceae, probably Circaeaster); (2) by a combination of postgenital fusion and secretion; (2a) with a complete secretory canal and partly postgenitally fused periphery (Lardizabalaceae, Menispermaceae, some Ranunculaceae, Sabiaceae); (2b) with an incomplete secretory canal and completely fused periphery (Tro-chodendron); (3) by complete postgenital fusion without a secretory canal (most Ranunculaceae, Eupteleaceae, Platanaceae, Proteaceae, all families of Saxifragales and incertae sedis studied here). Stigmas are double-crested and decurrent in most of the non-ranunculalian taxa; unicellular-papillate in most taxa, but with multicellular protuberances in Daphniphyllaceae and Hamamelidaceae. Carpels predominantly have three vascular bundles, but five in Proteales (without Nelumbonaceae), Myrothamnaceae and Trochodendraceae. The latter two also share ‘oil’ cells in the carpels. Stomata on the outer carpel surface are present in the majority of Ranunculales and Proteales, but tend to be lacking in the saxifragalian families. In basal eudicots, especially in the non-ranunculalian families there is a trend to form more than one ovule per carpel but to develop only one seed, likewise there is a trend to have immature ovules at anthesis. Ovule number per carpel is predominantly one or two. Proteales (without Nelumbonales) mainly have orthotropous ovules, the other groups have anatropous (or hemitropous or campylotropous) ovules. The outer integument is annular in the groups with orthotropous or hemitropous ovules, and also in a number of saxifragalian families with anatropous ovules. In Proteales the integuments are predominantly lobed but there is no distinct pattern in this feature among the other groups. Among Ranunculales two pairs of families (Lardizabalaceae/Menispermaceae and Bcrberidaceae/Papaveraceae) due to similarities in gynoecium structure can be recognized, which are not apparent in molecular analyses. The close relationship of Platanaceae and Proteaceae is supported by gynoecium structure but gynoecial features do not support their affinity to Nelumbonaceae. The alliance of Daphniphyllaceae with Hamamelidaceae s.l. is also supported.  相似文献   

6.
A new extinct genus of arborescent angiosperms, Tasymia gen. nov., is described from the Turonian deposits of the upper part of the Simonovo Formation on the Kas River (left-bank tributary of the Yenisei River, Krasnoyarsk Region). The epidermal characters of leaves of the new genus testify to its platanaceous affinity. A comparison with other extinct taxa of the Platanaceae from the Chulym-Yenisei Depression and other regions of the Northern Hemisphere is accomplished.  相似文献   

7.
Fossil leaves and associated reproductive structures from the Kundur locality, Amur Region, are examined. A new genus of the unlobed platanaceous leaves, Kunduriphyllum gen. nov. (Platanaceae) is described based on distinctive morphological and epidermal features. The similarity of epidermal characteristics and identical biological damage suggest that the leaves Kunduriphyllum kundurense gen. et comb. nov., staminate inflorescences Kundurianthus, and infructescences Kunduricarpus could be assigned to a single plant.  相似文献   

8.
More than ten extinct Lower Brachycera families have been discovered throughout the world. These fossil records are of great significance in piecing together jigsaw puzzles of evolution for the Order Diptera. However, the distinct systematic relationships of the Diptera, one of the four largest orders, remain obscure. Herein, we erect a new family to enhance our systematic understanding of the Diptera. The Uranorhagionidae fam. nov. is a bewildering new extinct family comprising two new genera, Uranorhagio gen. nov. and Strenorhagio gen. nov. , and five new species, Uranorhagio daohugouensis sp. nov. , Strenorhagio deviatus sp. nov. , Strenorhagio grimaldi sp. nov. , Strenorhagio asymmetricus sp. nov. , and Strenorhagio conjugovenius sp. nov. , from the Middle Jurassic of China. Members of the new family are moderate to large in size and robust in shape. This family possesses a peculiar shape of vein R2+3, the basal part of which is strongly fornical and nearly geniculate, and has the crossvein r–m at variable position. Furthermore, the Uranorhagionidae fam. nov. exhibits a mixture of distinct characters of two families in two disparate superfamilies, i.e. Rhagionemestriidae (Nemestrinoidea) and Rhagionidae (Tabanoidea), thus suggesting that this family might be in an inclusive position in dipteran phylogeny. We tentatively place this new family as a member of Tabanoidea, pending the discovery of more fossil specimens and further study. The comparison between the new family and other relative families will be discussed. © 2010 The Linnean Society of London, Zoological Journal of the Linnean Society, 2010, 158 , 563–572.  相似文献   

9.
This paper addresses the phylogeny of the superfamily Paratanaidoidea using computer‐assisted parsimony methods. Our morphologically based, empirical analysis uses exemplar species from all families and most genera in the superfamily. Species of Apseudomorpha, Neotanaidomorpha and Tanaidoidea were employed as out‐groups. The analysis supports most of the older systematics, including the monophyly of Paratanaididae, Leptocheliidae (in part), Nototanaididae, Pseudotanaididae and Pseudozeuxidae (excluding Heterotanaoides ). The analysis does not support the monophyly of Typhlotanaididae and Anarthruridae and suggests that both families be split up. The core genera of Typhlotanaididae are combined with the Nototanaididae under the name Nototanaididae. Other genera of Typhlotanaididae are left without family designation. Anarthruridae is divided into five families, Agathotanaididae, Anarthruridae, Leptognathiidae, Tanaellidae fam. nov. and Colletteidae fam. nov. , but a large part of the anarthrurid genera could not be designated to families. The Leptocheliidae could neither be rejected nor verified but a subfamilial division (Heterotanaidinae subfam. nov. and Leptocheliinae) seems appropriate. A new proposal for the higher‐level taxonomy of the Paratanaidoidea is presented. Many tanaidacean names have been corrected to make them agree with the presumed Latin stem ‘tanaid‐’.  相似文献   

10.
The present paper deals with the systematic position of Daphniphyllaceae. The genus Daphniphyllum was first described by Blume in 1826 as a member of Rhamnaceae. In 1858 Baillon removed it to the tribe Phyllantheae of Euphorbiaceae, while Müller (1869) raised this genus to the rank of family, Daphniphyllaceae. Although Müller’s treatment has been accepted by most botanists, including the present authors, its systematic position has been debated. The first aim in our studies on the cladistics of Hamamelidae is to answer the question which families should be included in this monophyletic group. By observing their pollen grains and stoma types of some representative species of Daphniphyllaceae, Hamamelidaceae and Buxaceae under light microscope (LM) and scanning electron microscope (SEM,) and analysing morphological, anatomical, palynological, embryological characters and chemical components in the three taxa and Euphorbiaceae, we find that Daphniphyllaceae is very similar to Hamamelidaceae, but greatly different from Euphorbiaceae, in inflorescence racemose or spicate, calyx nearly reduced, stamens numerous and sometimes synandry, connective usually exserted, disc absent, carpels 2; vessel with scalariform perforation plates and often not spiral-thickened, fiber bordered-pitted; stomata mostly paracytic; pollen 3-colpate; tapetum glandular, endosperm development cellular, obturator and caruncle absent; iridoid compounds present; sieve-element plastids S-type. The present authors have noticed the fact that Daphniphyllaceae is also similar to Magnoliaceae in the stamens numerous, anthers larger and filaments very short, connectives obviously exserted and with several bundles; anther wall thicker, endosperm development cellular, embryo small. It is considered that not only are Daphniphyllaceae and Hamamelidaceae phenetically close to each other but also much possibly derived from a common ancestor, the extinct group of Magnoliales. However, Daphniphyllaceae appears to be remote from Euphorbiaceae and Buxaceae in relationship and should be separated from Euphorbiales and Buxales. Meanwhile, since Daphniphyllaceae differs from the members of Hamamelidales in the incompletely septate ovary, drupaceous fruit, indistinct sexine sculpture of pollen grains, small embryo, and an unique alkaloid, daphniphylline, but lacking proanthacyanins, the establishment of an order, Daphniphyllales, for the family, is considered reasonable. According to our opinion, the order is related to Hamamelidales rather than to Euphorbiales as originally suggested by Huru-sawa (1954).  相似文献   

11.
12.
中国东北晚侏罗世虻类化石(昆虫纲:双翅目)   总被引:5,自引:0,他引:5  
本文论述了辽宁西部上侏罗统虻类6个科的化石,包括1新科,10个新属和15个新种。其中Palaepangonius eupterus gen.et sp.nov.,Elpangonius pletus gen,et sp.nov.和Allomyia ruderalis gen.et sp.nov.均属于虻科(Tabanidae);Orsobrachyceron chinensis gen.et sp  相似文献   

13.
Isomorphic polymorphism is demonstrated by modern and fossil members of the Platanaceae and Hamamelidaceae (subfamily Altingioideae) and is considered as evidence of structural parallelism in the evolution of the Platanaceae and Altingioideae. The supposed relationship between Platanaceae and Altingioideae is discussed from a paleobotanical perspective.  相似文献   

14.
Cambrian lobopodians–ancestors of extant onychophorans?   总被引:7,自引:0,他引:7  
This paper is a review of published information on fossil lobopodians, with addition of observations and ideas based on new material. It is also an analysis of the phytogeny of the group, and presents a new classification. A character shared by three or four families, yet not seen before, is a pair of enlarged sclerites covering the head. This forms an argument for re-orienting Hallucigenia once again. This genus no longer being enigmatic, a corner-stone in Stephen Jay Gould's evidence for extinct phyla is therefore gone. It is suggested that the lobopodians, phylum Lobopodia, are arranged in two classes, the extinct Xenusia for marine forms, and the Onychophora for terrestrial forms. The marine lobopodians are morphologically much more diverse than the extant onychophorans, a condition expressed in the classification. New taxa are: Hallucigenia fortis sp. nov., the families Luolishaniidae, Cardiodictyidae and Onychodictyidae, and the new orders Archonychophora, Scleronychophora and Paronychophora.  相似文献   

15.
16.
A new angiosperm fructification, Caloda delevoryana, is described from the Cenomanian age Dakota Formation of central Kansas. It consists of a long, narrow, main axis with numerous secondary axes arranged helically around the main axis. These secondary axes are each terminated in a small receptacle bearing numerous conduplicate carpels. No evidence of a perianth or androecium was found. This fructification bears some similarity to a number of different modern orders, such as the Hamamelidales, Alismatales, Najadales, and Piperales, and families, particularly the Platanaceae and the Aponogetonaceae, but cannot definitely be assigned to any modern taxon within the angiosperms. C. delevoryana exhibits several characters traditionally assumed to be primitive in the angiosperms, and several other features of this fossil are proposed as primitive in the evolution of angiosperms. This floral axis, with its compact mass of numerous secondary axes bearing very small fruits and seeds, may be the product of reduction through diminished growth of internodes and carpels, and elaboration through increased repetition of floral modules. This record adds to the rapidly growing body of paleobotanical data on early angiosperm reproductive structures, which should prove important in the assessment of the extent and direction of angiosperm evolution.  相似文献   

17.

Background

Lacewings (insect order Neuroptera), known in the fossil record since the Early Permian, were most diverse in the Mesozoic. A dramatic variety of forms ranged in that time from large butterfly-like Kalligrammatidae to minute two-winged Dipteromantispidae.

Principal Findings

We describe the intriguing new neuropteran family Parakseneuridae fam. nov. with three new genera and 15 new species from the Middle Jurassic of Daohugou (Inner Mongolia, China) and the Early/Middle Jurassic of Sai-Sagul (Kyrgyzstan): Parakseneura undula gen. et sp. nov., P. albomacula gen. et sp. nov., P. curvivenis gen. et sp. nov., P. nigromacula gen. et sp. nov., P. nigrolinea gen. et sp. nov., P. albadelta gen. et sp. nov., P. cavomaculata gen. et sp. nov., P. inflata gen. et sp. nov., P. metallica gen. et sp. nov., P. emarginata gen. et sp. nov., P. directa gen. et sp. nov., Pseudorapisma jurassicum gen. et sp. nov., P. angustipenne gen. et sp. nov., P. maculatum gen. et sp. nov. (Daohugou); Shuraboneura ovata gen. et sp. nov. (Sai-Sagul). The family comprises large neuropterans with most primitive wing venation in the order indicated by the presence of ScA and AA1+2, and the dichotomous branching of MP, CuA, CuP, AA3+4, AP1+2. The phylogenetic position of Parakseneuridae was investigated using a phylogenetic analysis of morphological scoring for 33 families of extinct and extant Neuropterida combined with DNA sequence data for representatives of all extant families. Parakseneuridae were recovered in a clade with Osmylopsychopidae, Prohemerobiidae, and Ithonidae.

Conclusions/Significance

The presence of the presumed AA1+2 in wings of Parakseneuridae is a unique plesiomorphic condition hitherto unknown in Neuropterida, the clade comprising Neuroptera, Megaloptera, Raphidioptera. The relative uncertainty of phylogenetic position of Parakseneuridae and the majority of other families of Neuroptera reflects deficient paleontological data, especially from critical important periods for the order, earliest Triassic and latest Triassic/earliest Jurassic.  相似文献   

18.
Jack A. Wolfe 《Brittonia》1973,25(4):334-355
Review of the procedures used in determining fossil plant organs indicates that the many Cretaceous records of extant genera of “Amentiferae” based on leaves should be rejected as theoretically unreliable. Palynological data, in combination with some valid megafossil data, indicate that most recognizable members of “Amentiferae” are no older than the later part of the Late Cretaceous. Juglandales appear to be derivatives of the ancient Normapolles complex and unrelated to other “Amentiferae.” A preliminary account of some of the comparative foliar morphology of extant “Amentiferae” indicates that some—particularly Betulaceae and Fagaceae—are closely related to Hamamelidales but that other families—notably Rhoipteleaceae, Juglandaceae, Didymelaceae, and Leitneriaceae—are unrelated to this order.  相似文献   

19.
The phylogeny of spider flies is presented based on an analysis of DNA sequence data combined with morphological characters for both living and fossil species. We sampled 40 extant and extinct genera across all major lineages of Acroceridae, which were compared with outgroup taxa from various lower brachyceran families. In all, 81 morphological characters of 60 extant and 10 extinct ingroup species were combined with 7.1 kb of DNA sequences of two nuclear (CAD and 28S rDNA) and two mitochondrial genes (COI and 16S rDNA). Results strongly support the monophyly of Acroceridae, with major clades contained within classified here in five extant subfamilies (Acrocerinae, Cyrtinae stat. rev. , Ogcodinae stat. rev. , Panopinae and Philopotinae) and one extinct subfamily, Archocyrtinae. The evolution of important spider fly traits is discussed, including genitalia and wing venation. The status of the enigmatic Psilodera Gray and Pterodontia Gray as members of the Panopinae is confirmed based on both molecular and morphological data.  相似文献   

20.
Three new fossil bryophytes are described from Jurassic and Lower Cretaceous deposits of the Transbaikalia region of Russia. The complex thalloid hepatic Khasurtythallus monosolenioides gen. et sp. nov. belongs to the Marchantiidae, but its combination of characters precludes unequivocal placement in any of the five orders of this subclass, representing most likely an extinct lineage. Paleaethallus squarrosus gen. et sp. nov. is a thalloid plant with scales similar to those of complex thalloid hepatics, although their arrangement and the overall plant structure has little in common with any extant hepatics. Dispersed moss capsules, three of which have attached calyptrae, are described as a form genus Kulindobryum gen. nov. Despite incomplete preservation, some rare characters indicate possible relationship to the genus Tayloria of the Splachnaceae, an extant family of mosses adapted to grow on animal dung, dead bodies and bones. Notably, Kulindobryum co‐occurs with bones of the small feathered dinosaurs Kulindadromeus, which also supports an affiliation of Kulindobryum with the Splachnaceae. The most common and best known Mesozoic moss for the region, the genus Bryokhutuliinia, is appraised for its systematic position and probable affinities with the Dicranales. A scoring approach is introduced for the comparative method of taxonomic placement of fossils with partial suites of morphological characters at the family or order level.  相似文献   

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