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R. T. PENNINGTON B. GEMEINHOLZER 《Botanical journal of the Linnean Society. Linnean Society of London》2000,134(1-2):267-286
Andira comprises 29 species distributed throughout tropical America, with two subspecies in Africa. Its fruits are unusual for a papilionoid legume because they are drupes. The majority of species have fruits dispersed by bats, but eight species have larger fruits dispersed by-rodents. Some fruits of both dispersal types are secondarily dispersed by water. Cladistic analysis of chloroplast DNA (cpDNA) restriction site characters discovered four well-supported clades of Andira species. None of these 'cryptic' clades had been recognized by previous workers, because they are not apparently marked by any known morphological innovations. This prompted a search for new characters that might support these groupings. An anatomical study of fruit walls of 25 Andira species revealed the presence of three principal endocarp types, dominated by (1) parenchyma, (2) fibres, or (3) stone cells. These features arc best coded as a single unordered multistate character. When incorporated into a simultaneous cladistic analysis of previously gathered molecular and morphological data, states of this endocarp character are shown to be apomorphies for two of the well-supported clades evident in the cpDNA restriction site data. The most likely plesiomorphic state for the endocarp is parenchyma-dominated. Thicker, stronger endocarps of fibres and stone cells may have evolved in response to the need to protect the seed from predators. 相似文献
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Mohamed Charni Abdel Halim Harrath Ronald Sluys Saida Tekaya Fathia Zghal 《Hydrobiologia》2004,517(1-3):161-170
A study was carried out on freshwater planarians of the genus Dugesia from three localities in northern Tunisia: Joumine, Chiba, and Lebna. The three populations are fissiparous under field conditions and do not possess reproductive organs, except for some cases of hyperplastic ovaries in the Joumine population. After five months of breeding under laboratory conditions, with water temparature between 18 and 25?°C and under short photoperiod, 8.33 to 26% of specimens from the Joumine stream became sexualized, together with considerable increase of body length and width. For the other two populations the sexualization rate was very small. Extended period of darkness apparently played a positive role in this sexualization. The phenomenon of sexualization is discussed in the context of reproductive strategies. Histological and karyological studies of the sexualized animals allowed identification of these usually fissiparous planarians as representatives of Dugesia sicula Lepori, 1948. The species is here reported for the first time from Tunisia. The populations are restricted to permanent water basins resulting from the construction of dams in large rivers. 相似文献
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Species of the family Epipyropidae are infrequently collected due to their ectoparasitic lifestyle and have therefore received little study. Based on our morphological and molecular analyses, all specimens found parasitizing different species of cicadas in China belong to one species, Epipomponia nawai (Dyar). The species Epipomponia oncotympana Yang (nom. invalid.) was found to be identical with E. nawai. The morphology of the egg, larva, pupa, and adult of E. nawai is described, including the ultrastructure of the egg and larva. Seven types of sensilla and their distribution pattern on the antennae of both females and males of E. nawai are examined using scanning electron microscopy, resulting in a better understanding of sexual dimorphism in this species. Population differentiation and phylogenetic relationships amongst populations of E. nawai occurring in China, the Korean Peninsula, and Japan are analysed. The intraspecific genetic distances suggest a low genetic differentiation which is also consistent with the minor morphological variations. The biogeographic analysis reveals that the Qinling Mountain Range, which is geographically the border of the subtropical and temperate zones, is presumably one of the most important geographic barriers to the gene flow of E. nawai. Our molecular phylogenetic analysis based on the COI gene of E. nawai indicates that frequent gene flow might have occurred in the China mainland, Taiwan and Japan islands, and possibly also the Ryukyu Islands after the Quaternary ice ages. In addition, the biology and behaviour of both larvae and adults of E. nawai were also observed, and results indicate the possibility of bisexual reproduction in this moth. Our results increase the understanding of the morphology, diversity, distribution, and biology of this unusual moth, and should aid future studies on patterns of population differentiation, biogeography, and reproductive behaviour in other epipyropids. 相似文献
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Gaimardia ( Neogaimardia ) finlayi Powell 1933 is a member of the little known family Gaimardiidae which collectively have an Australian, New Zealand and sub-Antarctic distribution. N. finlayi nestles amongst algal holdfasts at the bottom of wave-exposed beaches in New Zealand. It is a small, weakly heteromyarian dioecious bivalve attached by a relatively stout byssus. The mantle and the siphons are exceedingly simple; mantle fusions, other than anterior and posterior to the internal ligament, are of the inner folds only. The siphons are non-extensible wide openings with few sensory papillae. Each ctenidium comprises an inner demibranch only with no inter-lamellar and but a few inter-filamentar junctions. Within the ctenidium large telolecithal eggs are incubated to a crawling, shelled stage of approximately 0–75 mm in length. Sperm were found in the ctenidium of two mature males. The possible storage of sperm and eggs and the incubation of fertilized eggs have survival value for a small bivalve living in a difficult environment.
The modifications which suit N. finlayi to its mode of life are discussed, but major interest centres around the taxonomic position of the Gaimardiidae. It is concluded that the Cyamiidae and Gaimardiidae are very closely related, but more comprehensive studies on representatives of both families are needed. 相似文献
The modifications which suit N. finlayi to its mode of life are discussed, but major interest centres around the taxonomic position of the Gaimardiidae. It is concluded that the Cyamiidae and Gaimardiidae are very closely related, but more comprehensive studies on representatives of both families are needed. 相似文献
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Sperm morphology of salamandrids (Amphibia, Urodela): implications for phylogeny and fertilization biology 总被引:3,自引:0,他引:3
Mature spermatozoa belonging to four salamander species, Salamandrina terdigitata, Triturus alpestris, Triturus carnifex and Triturus vulgaris, have been investigated by electron microscopy. The sperm ultrastructure of these species was compared with that of previously examined urodeles (36 species and 20 genera) and with that of anurans and caecilians. Many phylogenetic considerations may be inferred as a consequence of comparative spermatology. Urodela appears to be a monophyletic order characterized by three sperm synapomorphies: the acrosomal barb, nuclear ridge and marginal filament. Cryptobranchoidea are confirmed to form a monophyletic suborder having two synapomorphic characters: absence of mitochondria in the tail, and cylindrical shape of the tail axial rod. Within the family Salamandridae, sperm morphology confirms the phylogenetic distance between Salamandrina and Triturus, as already pointed out on the basis of molecular and morphological characters. The very complex ultrastructure of spermatozoa confirms a previous opinion that internal fertilization is the ancestral condition of the Amphibia. 相似文献
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P. Brönnimann 《Pal?ontologische Zeitschrift》1986,60(1-2):29-44
The morphology of the brackish waterAmmoastuta salsa Cushman and Brönnimann, the type species ofAmmoastuta, is revised and the genus definition emended. In view of the early planispiral coil, the late uniserial development which tends toward rectilinear, the imperforate agglutinated wall, the multiple aperture and the simple interior, the Ammoastutinae Loeblich and Tappan 1984, are placed into the Lituolidae de Blainville 1827, emended herein, of the Lituolacea DE Blainville 1827, emended herein. 相似文献
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Maria Grochowska 《Acta zoologica》2006,87(4):247-252
The egg, second‐ and third‐instar larvae and puparium of Cleigastra apicalis are described for the first time. All pre‐imaginal stages are found on stems of the common reed affected by flies of the genera Lipara and Platycephala and the butterfly Arenostola phragmitidis. The larvae feed on dead plant and animal tissue and the excreta of other insects that live inside the stems of the common reed. Exceptionally they will scrape living plant tissue. The pupa is the overwintering stage. 相似文献
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Capillaria hepatica (Bancroft, 1893) in Appalachian mammals 总被引:1,自引:0,他引:1
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Although Codfishes are probably one of the most studied groups of all teleost fishes worldwide owing to their great importance to fisheries, their phylogeny and classification are still far from being firmly established. In this study, we present phylogenetic relationships of 19 out of 22 genera traditionally included in the Gadidae based on the analysis of entire cytochrome b and partial cytochrome oxidase I genes (1530 bp). Maximum Parsimony, Maximum Likelihood, and Bayesian analyses all recovered five main clades that correspond to traditionally recognized groupings within Gadoids. The same clades were recovered with MP analysis based on 30 morphological characters (collected from the literature). Given these findings, we propose a revised provisional classification of Gadoids: one suborder Gadoidei containing two families, the Merlucciidae (1 genus) and the Gadidae (21 genera) distributed into four subfamilies: the Gadinae (12 genera), the Lotinae (3 genera), the Gaidropsarinae (3 genera), and the Phycinae (3 genera). Lastly, nuclear inserts of mitochondrial DNA (Numts) were identified in two species, i.e., Gadiculus argenteus and Melanogrammus aeglefinus. 相似文献