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1.
The fossil pollen genus Classopollis 总被引:2,自引:0,他引:2
SATISH K. SRIVASTAVA 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1976,9(4):437-457
The generic name Classopollis Pflug, 1953, is considered as a valid usable name for Mesozoic spherical pollen characterized by a subequatorial circumpolar canal, a thickened equatorial band, a distal cryptopore, and a proximal tetrad scar. A study of Classopollis exine revealed the absence of nexine. Classopollis has a worldwide distribution in Upper Triassic-Turonian strata. Plants producing Classopollis have affinity with araucarian and/or gnetalean conifers. They occupied well-drained soils of upland slopes and lowlands near coastal areas, preferring the warm climate of transgressive seas. 相似文献
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The fossil record of Araceae pollen beginning in the late Early Cretaceous and peaking in the Paleocene/Eocene is very sparse
up to now, consisting of three highly distinctive types: zona-aperturate pollen of the Monstera or Gonatopus type (very similar to Proxapertites operculatus), an ulcerate-spiny type typical for Limnobiophyllum, and a polyplicate, omniaperturate pollen type (an ephedroid pollen with non-gnetalean affinities) which was recently reported
from the late Early Cretaceous (Mayoa portugallica). An extensive literature search has shown that some distinctive Ephedripites forms (the Paleogene Ephedripites vanegensis, and the Late Cretaceous Ephedripites elsikii) are very similar to pollen of Spathiphyllum and both species are here transferred from Ephedripites to Spathiphyllum (as comb. nov.). We also add new fossil findings to the Araceae record. The new findings include a zona-aperturate, microperforate
to microreticulate pollen type from the Palaeocene of Colombia, highly similar to extant Gonatopus or Zamioculcas or Monstera pollen (Araceae) and to fossil Proxapertites operculatus, which is currently seen as a fossil equivalent; and, an ulcerate, spiny pollen from the Eocene of Stolzenbach, Germany,
extending the range of Limnobiophyllum (Pandaniidites), which is thought to be an extinct member of extant Araceae. The three pollen types add considerably to the reliable fossil
record of the family that now contains more than 20 records of these three pollen types: with the zona-aperturate type recorded
from the tropical or subtropical regions of Northern and Southern America, Central Africa, Southern and Central Europe, from
the Indian subcontinent and the Malayan Archipelago; the ulcerate type occurring in North America and Europe; and the polyplicate
type mainly occurring in South America and South-West Europe. Now we have good evidence that some of the aroid subfamilies
were already in existence in the Cretaceous, increasing in diversity and worldwide distribution in the Paleogene.
Dedicated to Prof. Dr. Stefan Vogel on the occasion of his 80th birthday. 相似文献
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Ralph I. Smith 《Journal of morphology》1992,213(3):365-393
A comparative morphological study of nephromixial systems in three Californian terebellid polchaetes currently assigned to the genus Pista shows that P. fimbriata has all attributes of the generic type, but that P. pacifica and P. elongata differ markedly. The features of typical Pista include (among others): two pairs of usually unequal branchiae, long-handled anterior uncini (hooks) of crested avicular (bird-head-like) from, muddy, unornamented tubes, one pair of anterior excretory nephromixia (ENMX), and two pairs of separate thoracic reproductive nephromixia (RNMX) with genital papillae on segments VI and VII. A review indicates that P. fimbriata shares these typical features with practically all adequately described Pista species. However, P. pacifica and P. elongata possess three pairs of branchiae, long-handled uncini of distinctive crochet-like form, and membranous tubes with apertural hoods. Both have two pairs of ENMX, the first supplied by one pair of ciliated renal funnels, the second by two pairs of such funnels. But they differ in their RNMX: P. pacifica has three pairs of complex RNMX, those on each side united by a common duct. P. elongata has 11–13 pairs of simple RNMX united by common ducts. Although these species do not fit into Pista, no genus has been found to accommodate them. Generic placement is complicated by the fact that no instances of intra-generic nephromixial variation have been reported in the Terebellidae, although inter-generic variation is well known. If they are congeneric, this would be the first example of intrageneric RNMX variation in Terebellidae. But if assigned to separate genera or subgenera on the basis of their RNMX, their similarity of anterior uncini might be attributable to parallel or convergent adaptation to life in comparable tubes. More evidence, including molecular analysis, is needed for phylogenetic studies of Terebellidae. © 1992 Wiley-Liss, Inc. 相似文献
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In vitro pollen germination of five species and two interspecific hybrids from the genus Brassica was tested in four media. Genetically fixed differences in the demands for optimal pollen germination among species were found. The experiments were designed to define optimal content of mineral salts, sugar, and PEG for every investigated species or hybrids. The differences found among species are discussed in relation to the evolutionary trend. 相似文献
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K. L. ALVIN F.L.S. A. HLUTÍK 《Botanical journal of the Linnean Society. Linnean Society of London》1979,79(3):231-241
Shoots of the fossil species Frenelopsis alata (K. Feistmantel) Knobloch (Cheirolopidiaceae) from the Cenomanian of Bohemia and Portugal demonstrate a type of branching not hitherto reported among conifers. It has been interpreted as a modification of conventional axillary branching on the basis of detailed observations on external morphology with the help of comparative studies on living species of the family Cupressaceae (e.g., Callitris species) and other fossils of frenelopsid affinity. The probable nature of the growth pattern of the shoot is discussed. 相似文献
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The recently extinct large-bodied New World monkey Protopithecus brasiliensis Lund 1836 was named based on a distal humerus and proximal femur found in the Lagoa Santa cave system in the southeastern Brazilian state of Minas Gerais. These bones are from an animal about twice the size of the largest extant platyrrhines. One hundred and seventy-five years later, a nearly complete skeleton was discovered in the Toca da Boa Vista caves in the neighboring state of Bahia and was allocated to the same taxon as it was the first platyrrhine fossil of comparable size found since the originals. Our detailed study of the equivalent elements, however, reveals important morphological differences that do not correspond to intraspecific variation as we know it in related platyrrhine taxa. The presence of both an expanded brachioradialis flange on the humerus and gluteal tuberosity on the femur of the Bahian skeleton distinguishes it from the Lagoa Santa fossil as well as from all other platyrrhines. Further cranial and postcranial evidence suggests a closer relationship of the former with the alouattine Alouatta, while the limited Lund material fits more comfortably with the ateline clade. Therefore, we propose to limit P. brasiliensis Lund to the distal humerus and proximal femur from Lagoa Santa and erect a new genus and species for the skeleton from Toca da Boa Vista. Cartelles coimbrafilhoi was a large-bodied frugivore with a relatively small brain and diverse locomotor repertoire including both suspension and climbing that expands the range of platyrrhine biodiversity beyond the dimensions of the living neotropical primates. 相似文献
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Fossil Apis species from the Oligocene, Miocene and Plio-Pleistocene of Eurasia are described and their relationships with Recent species are discussed. Several new populations of fossil bees are reported from the Oligocene and Miocene of France and Spain, including Apis aquisextusensis sp. nov. The present state of knowledge of fossil bee systematics is poor because of the general lack of preserved characters. Some of the problems, and items requiring further investigation, are identified. 相似文献
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Dorota Wro��ska-Pilarek Andrzej M. Jagodzi��ski 《Plant Systematics and Evolution》2011,295(1-4):55-72
The aim of this study is verification of the taxonomic usefulness of the pollen grain features studied, based on pollen morphology of 32 wild species from all 4 subgenera and all 10 sections of the genus Rosa, mainly for delimitation of subgenera, sections, and species. The measurements and observations were carried out with both light microscopy and scanning electron microscopy. Only correctly formed pollen grains (30 per specimen) were measured, and 960 pollen grains were examined in total. They were analyzed for 14 quantitative features of pollen grains and exine sculpturing and the following qualitative ones: outline, shape, and operculum structure. Our study revealed that the diagnostic features of pollen grains studied were: exine sculpture, length of polar axis, and pollen shape (P/E ratio). On the basis of the above characters, five species were isolated and the remaining ones were included in several groups isolated on the basis of exine sculpture types. The following three exine sculpture types occurred in the species studied: granular-verrucate (in R.?stellata), striate-psilate (in R.?multibracteata and R.?multiflora), and striate (the remaining species). R.?banksiae is characterized by small pollen grains, while R.?setigera has strongly elongated pollen with P/E ratio >1.5. Exine sculpture features considered to be diagnostic should be treated as auxiliary because they fail to differentiate individual species, although they can be helpful in distinguishing groups of species of similar exine sculpture. The arrangement of the species examined on a dendrogram only slightly corroborates division of the Rosa genus into subgenera and sections currently adopted in taxonomy (Rehder 1940). An interesting result was reported for the species studied from the Caninae (R.?agrestis, R.?canina, R.?dumalis, R.?jundzillii, and R.?rubiginosa) section which, despite hybrid nature, with the exception of R.?villosa, grouped in the same, most separated group of species. 相似文献
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Fossil onagraceous pollen grains from two Upper Miocene localities in E. Austria were investigated by LM and EM. Exine structure and sculpture as well as viscin threads suggest affinities with the extant genusCircea. 相似文献
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We conducted a taxonomic review of the genus Microbispora using chemotaxonomic and DNA-DNA hybridization techniques, and reached the following conclusions: Microbispora viridis should be transferred to the genus Actinomadura as Actinomadura rugatobispora comb. nov., nom. nov. (type strain SF2240 = IFO 14382 = JCM 3366) and Microbispora echinospora should be transferred to the genus Actinomadura as Actinomadura echinospora comb. nov. (type strain JCM 3148 = ATCC 27300). We also propose that Microbispora rosea, Microbispora amethystogenes, Microbispora chromogenes, Microbispora diastatica, Microbispora indica, Microbispora karnatakensis and Microbispora parva should be combined into the species Microbispora rosea subsp. rosea (type strain JCM 3006 = ATCC 12950), and that Microbispora aerata, Microbispora thermodiastatica and Microbispora thermorosea should be combined and transferred to the new subspecies Microbispora rosea subsp. aerata comb. nov. (type strain IFO 12581 = ATCC 15448). Microbispora bispora clearly differs from these ten strains at the species level. 相似文献
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C J Brown V G Dunbar D A Shafer 《Folia primatologica; international journal of primatology》1986,46(3):164-172
Karyotypes from 72-hour whole blood cultures were compared for six species of macaques (Macaca arctoides, M. fascicularis, M. mulatta, M. nemestrina, M. nigra, and M. radiata) and one species of mangabey (Cercocebus atys). G-bands, sequential C-bands, and late replication patterns were studied. Results showed a variation in a single chromosome pair which differentiated C. atys from the macaques. Heteromorphic variation in silver stained nucleolar organizing regions was seen between and within individuals. This data supports previous work showing the highly conserved nature of the chromosomes of the subfamily Cercopithecus. 相似文献
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J E Ubelaker 《The Journal of parasitology》1986,72(2):237-244
Based on morphological criteria of the male bursa, angiostrongylid nematodes often placed in the genus Angiostrongylus Kamensky (1905) were found to be heterogeneous, comprising species which are relegated to 5 distinct genera: Angiostrongylus Kamensky, 1905 (syn. Haemostrongylus Railliet and Henry, 1907); Parastrongylus Baylis, 1928 (syn. Pulmonema Chen, 1935, Rattostrongylus Schulz, 1951, Morerastrongylus Chabaud, 1972, Chabaudistrongylus Kontrimavichus and Delyamure, 1979); Angiocaulus Schulz, Orlov and Kutass, 1933; Gallegostrongylus Mas-Coma, 1977 (syn. Thaistrongylus Ohbayashi, Kamiya and Bhaibulaya, 1979 n. syn); and Stefanskostrongylus Drozdz, 1970. These genera all contain species located primarily in specific host groups: Angiostrongylus in carnivores; Parastrongylus in rodents (Muridae), Angiocaulus in mustelids; Rodentocaulus in rodents (Cricetinae), Gallegostrongylus in rodents (Muridae), and Stefanskostrongylus in insectivores. Species in each genus include: Angiostrongylus (A. vasorum, A. raillieti, A. chabaudi); Parastrongylus (P. tateronae, P. cantonensis, P. mackerrasae, P. sandarsae, P. sciuri, P. petrowi n. comb., P. dujardini, P. schmidti, P. costaricensis n. comb., P. malaysiensis n. comb., P. ryjikovi n. comb., P. siamensis n. comb.); Angiocaulus (A. gubernaculatus, A. ten n. comb., A. sp. Caballero, 1951); Rodentocaulus (R. ondatrae) and Gallegostrongylus (G. ibicensis, G. andersoni, G. harinasutai n. comb.). Angiostrongylus pulmonalis is likely similar to Stefanskostrongylus soricis and is transferred to this genus. Angiostrongylus minutus is removed to Stefanskostrongylus. 相似文献
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A survey of the genus Sorbaria (Rosaceae) 总被引:1,自引:0,他引:1
Knud Rahn 《Nordic Journal of Botany》1989,8(6):557-563
A taxonomic revision of the Asiatic genus Sorbaria (Rosaceae). 4 species are recognized: S. sorbifolia (including S. stellipila), S. grandiflora (= S. pallasii incl. S. rhoifolia), S. kirilowii,(incl. S. arborea and S. assurgens ) and S. tomentosa (= S. lindleyana , incl. S. olgae and S. gilgitensis ) with var. angustifolia , comb. nov. (= S. aitchisonii ). Hybrids presumably between S. sorbifolia and S. grandiflora and S. sorbifolia and S. kirilowii are found cultivated. 相似文献
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Sinocalopteryx shangyongensis nov. gen., nov. sp., the first fossil calopterygoid from eastern Asia, is described from the earliest Eocene of Southwest China. Although the new genus has the principle synapomorphies of Calopterygoidea, it possesses a unique structure (possible reversal) in the pattern of vein RP1/2. 相似文献
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The use of sieving during standard pollen pre-treatment of samples of fossil deposits to enhance the concentration of large pollen grains 总被引:1,自引:1,他引:1
Small pollen grains and fine particles of the organic matrix in samples of a coarse detritus mud and a blanket peal deposit were removed by sieving through 30μ polyester mesh after digestion with KOH and acetolysis during standard pollen pre-treatment. The technique enhanced the number of large pollen grains m the sample. There was also an increase in the range of taxa which produce huge grains. The method provided a means of estimating the ratio of any scarce large pollen grain to the total grain sum in samples prepared by standard methods of pre-treatment. 相似文献