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1.
A marattialean fern,Scolecopteris libera n. sp., from the Asselian (Permian) of Inner Mongolia,China
《Palaeoworld》2019,28(4):487-507
Scolecopteris libera n. sp. is established on partial three-dimensionally preserved materials containing both sterile and fertile fronds collected from the volcanic tuff at the top of the Taiyuan Formation at the Wuda Coalfield, Inner Mongolia, China. It is characterized by tripinnate fronds with rachises over 200 mm in diameter; and long lanceolate or falciform pinnules with thick veins. Pinnules are of the pecopterid-type, with those at the base of the ultimate pinnae usually divided into small lobes. Eight to twelve circular synangia are arranged in two rows along the midvein. Synangia are borne on a short pedicel attached to the middle of lateral veins. A synangium is composed of 7–10 fusiform exannulate sporangia with pointed apices. The sporangia are free among each other beyond the base of synangia. In situ microspores of the Cyclogranisporites leopoldii type differ from all other in situ Paleozoic marattialean spores. 相似文献
2.
John G. Conran Uwe Kaulfuss Dallas C. Mildenhall 《Review of Palaeobotany and Palynology》2010,162(1):84-94
Fossil fern fronds referable to the extant fern genus Davallia (Polypodiales: Davalliaceae) bearing sporangia with in situ spores are described from the Early Miocene Foulden Maar diatomite deposit, Otago, New Zealand. The fronds are the first published Southern Hemisphere macrofossil record for the family and provide valuable palaeoclimate data supporting warm conditions in Early Miocene New Zealand. The matching of Davallia fronds to the form spore taxon Polypodiisporites radiatus shows that the genus has had a long, apparently continuous history throughout late Cenozoic New Zealand. 相似文献
3.
The pollen organ Feraxotheca gen. n. is described from Pennsylvanian age coal balls from the Lewis Creek, Kentucky, locality. The fructifications consist of bilaterally symmetrical synangia composed of a basal pad supporting elongate sporangia that are laterally appressed for the entire length of the sporangial cavities. Sporangial tips extend over the center of the synangium and delimit a small open area, while the bases arise from a parenchymatous cushion that is bounded by short tracheid-like cells. Each synangium is borne on the surface of an expanded pinna tip and is surrounded by a small amount of laminar tissue that envelopes the base of the synangium. Ultimate pinnae are rectangular in transverse section, possess an elliptical vascular bundle surrounded by canals containing a yellow froth-like substance, and have a cortex of elongate cells that radiate from the center of the axis. Sporangia contain small (40–64 μm), radial, trilete spores ornamented by regularly spaced coni or blunt tipped grana. Feraxotheca is compared with the compression genus Crossotheca and some new ideas are advanced concerning the morphology of this compression genus. The obvious differences between Feraxotheca and other lyginopterid pollen organs strongly suggests that the Lyginopteridaceae, as it is currently interpreted, is an unnatural family. 相似文献
4.
Gnetalean compression-impression fossils are described from the Early Cretaceous Yixian Formation, Liaoning Province, north-eastern
China, and assigned to six species of Liaoxia Cao et S.Q. Wu. The fossils have opposite-decussate phyllotaxis and cones comprising 2–12 pairs of bracts. Ovulate cones
have seeds typically in a distal position. The species differ from each other and from previously described fossils in the
absence or presence of leaves, shape of cones and seeds, and shape and position of cone bracts. The species of Liaoxia are probably close relatives of extant species of Ephedra L., but diagnostic reproductive details that could confirm this hypothesis are not preserved. The restricted information
in the fossils and the poorly understood morphological diversity of extant Ephedra, prevent assignment of the fossils to any particular subgroup of Ephedra, as well as an explicit exclusion of them from the extant genus. 相似文献
5.
6.
Michael A. Millay 《American journal of botany》1977,64(2):223-229
Material described by Graham as Cyathotrachus bulbaceus is believed to represent a new genus that is a common constituent of Upper Pennsylvanian coal balls. The sessile synangia of Acaulangium gen. n. are borne in a row on either side of the pinnule midrib and are composed of four to six short, tapering, laterally appressed sporangia. The sporangia have extended tips which curve over the inside of the synangium distally and delimit a small open area inside the synangium. The outer facing walls of the sporangia are two to three cells thick throughout while the inner facing walls are uniseriate. During dehiscence the sporangia separate laterally and spore release results from the rupture of a row of elongate cells along the inner sporangium midline. Among species of Scolecopteris the new genus resembles S. illinoensis and S. minor var. parvifolia but differs in its sessile synangial attachment. The additional parenchyma present between sporangial cavities in the synangia of Acaulangium, and the tendency toward bilateral symmetry suggests an early stage in the evolution of a bivalve synangium such as is present in Marattia. 相似文献
7.
The genus Osmunda L. contains approximately 10 extant species widely distributed in tropical and temperate regions, with the greatest concentration of species in East and Southeast Asia. Osmunda is characterized by dimorphic or commonly hemidimorphic fronds with dimorphic pinnae. Its geological history has been traced back to the Triassic. Most records of the genus are based on rhizomes and rarely on pinnae bearing sporangia and spores. Here, we describe fossil pinnae, sporangia, and spores of Osmunda lignitum (Giebel) Stur recovered from the middle Eocene of the Changchang Formation in the Changchang Basin, Hainan Island and the Youganwo Formation in the Maoming Basin, Guangdong, South China. The fossils closely resemble the extant Osmunda banksiifolia (C. Presl) Kuhn of the subgenus Plenasium on the basis of their morphological and anatomical structures. The present occurrence of O. lignitum indicates subg. Plenasium flourished and extended from the high latitude regions such as Northeast China to the low latitude areas of South China during the middle Eocene. Large numbers of specimens described here also indicate that Osmunda was the dominant understory fern element beneath mixed evergreen broad-leaf angiosperm and gymnosperm forests living in a warm and humid environment. 相似文献
8.
Middle Jurassic fossils of the genus Sharasargus from Inner Mongolia, China (Diptera: Archisargidae)
To date, only two species of the genus Sharasargus are known. These Upper Jurassic species were found in Mongolia and Kazakhstan, respectively. We herein describe two new species from the Middle Jurassic, which were found in Inner Mongolia, China. They are the oldest known fossils of this genus. A key to Sharasargus species is given. 相似文献
9.
Lindsay S. Olive 《American journal of botany》1962,49(3):297-303
Olive , L. S. (Columbia U., New York, N. Y.) The genus Protostelium . Amer. Jour. Bot. 49(3): 297–303. Illus. 1962.—Two new species of this simplest genus of the cellular slime molds are described: P. fimicola , a species with spherical spores and gelatinizing stalks occurring on dung, and P. arachispora , an elongate-spored species from dead plant material. The first has been found in North Carolina and the West Indies, while the second species has been found only once in North Carolina. Protostelium mycophaga var. major , from Connecticut, has distinctly larger spores than the original species. Further data on the distribution and development of P. mycophaga are presented. The genus is transferred to a family of its own, the Protosteliaceae . 相似文献
10.
《Palaeoworld》2023,32(1):116-123
The oldest fossils assigned to Athyrium (mostly based on the sorus morphology) comprise fronds and spores from the Lower Cretaceous of Northeast Asia. However, most molecular dating suggests that extant Athyrium diverged from its sister genus during the Eocene or later, implying that the Cretaceous fossils probably belong to another polypodiaceous taxon. By examining the sorus morphology of extant genera related to the family Athyriaceae, we found that the primary diagnostic feature for assigning the Cretaceous fossils to Athyrium, i.e., the sorus shape, is common to the entire extant family, or plesiomorphic for the genus. As the fronds are more commonly preserved than the reproductive parts, we compared the fossil frond morphology with those of living taxa of the family that is divided into two types. The Cretaceous fossil we examined here bears the frond’s costal groove characters on adaxial side, which is more closely related to that of the Deparia-clade instead of the clade including Athyrium and other genera of the family. The observation is further confirmed by the cladistic analysis using morphological characters. The systematic position of the Early Cretaceous “Athyrium” was resolved as a stem member of the total Athyriaceae using a tip-dating approach with the Fossilized Birth-Death model in a Bayesian framework. Our study suggests that Early Cretaceous fossils previously assigned to Athyrium require taxonomic revision. 相似文献
11.
Abstract A new fossil genus and species of the family Mesosciophilidae, Huaxiasciophilites jingxiensis gen. et sp. nov. is described. The fossils of the new genus and species were collected from the Early Cretaceous Lushangfen Formation (K41 1) of Jingxi basin of Beijing China. The new genus is established based on the following characters: that Sc short, not exceed the forking of R and Rs, with branches; r‐m longer than basal part of Rs; Rs very thick and undee; and radial cell very short. The phylogenetic tree of Mesosciophilidae superimposed on the geological time scale was also analyzed. The holotype is deposited in the Beijing Forestry University. 相似文献
12.
A new species of the uncommon microsporidian genus Telomyxa (Microspora: Telomyxidae) has been found parasitizing the larval fat body of the semiaquatic beetle, Ora texana. In this species, the sporogonic sequence results in the formation of sporocysts measuring 7.7 times 6.5 μm that contain two crested uninucleate spores (averaging 5.7 times 2.2 μm). The spores are essentially oblong/ovate, tapering toward the anterior end and remaining bound together after sporogony by a persistent accessory membrane or sporocyst. The two spores in the sporocyst are produced by an unusual morphogenetic sequence in which, after one mitosis, the binucleate sporont elongates, forming two lobes that fold toward one another and cleave along a central plane, forming two parallel sporoblasts. The general ultrastructural features of this process are described, and diagnostic characters of this new species of Telomyxa are presented. 相似文献
13.
E. M. Friis K. Raunsgaard Pedersen J. Schönenberger 《Plant Systematics and Evolution》2006,260(2-4):107-140
The Normapolles complex, characterised by its oblate and triaperturate pollen, constitutes an important and diverse element
of many Late Cretaceous and Early Cainozoic floras of the Northern Hemisphere. Based on the dispersed pollen record alone
it has been difficult to assess systematic affinities, but relationships with Fagales have been proposed. Over the past twenty
years several exquisitely preserved Late Cretaceous reproductive structures with Normapolles type pollen in situ have been described. In this study we provide a summary and new information of these floral structures. Further, a new genus,
Dahlgrenianthus, is described from the Late Cretaceous of southern Sweden. The genus includes the type species Dahlgrenianthus suecicus, a number of reproductive structures referred to Dahlgrenianthus sp., and Dahlgrenianthus trigonus (Knobloch et Mai) comb. nov. from the Maastrichtian flora of Walbeck, Germany. Dahlgrenianthus comprises small flowers with pentamerous perianth and androecium and a tricarpellate gynoecium. It is distinguished from
all other Normapolles floral structures in its hypogynous floral organisation. All Normapolles floral structures described
so far are thought to be related to various members of the core Fagales, but the group is obviously not monophyletic. The
stratigraphic range of the Normapolles taxa and other fagalean fossils strongly suggests that all major fagalean lineages
were present by the Cenomanian or earlier. 相似文献
14.
N. D. Sinitshenkova 《Paleontological Journal》2011,45(5):552-558
From the Lower Cretaceous locality Khasurty, western Transbaikalia, a new genus and species, Rasnitsyrina culonga, gen. et sp. nov. are described in the family Perlariopseidae. R. desiliens (Sinitshenkova, 1987), originally described in the genus Karanemoura Sinitshenkova, 1987, is transferred to the new genus. Two new species belonging to recent families are described: Dimoula khasurtensis sp. nov. (Nemouridae) and Jurataenionema rohdendorfi sp. nov. (Taeniopterygidae). All new species are described from fossils of adults. 相似文献
15.
Electron microscopy of haplosporidan spores from Teredo navalis and T. furcifera revealed 4 distinct membrane-bound extensions, 1 apical extension opposite the opercular hinge, 1 terminal and 2 opposing lateral extensions. These extensions were not continuous with the spore wall, but contained microtubule-like structures and degrading epispore cytoplasm. No other known species in the family Haplosporidiidae is characterized by spores possessing four epispore extensions. There are currently two genera in this family, Minchinia and Haplosporidium. The genus Minchinia includes spores such as those of M. chitonis which bear two epispore cytoplasm extensions. Spores of the genus Haplosporidium have been characterized by spore wall derived filaments. A 3rd group of haplosporidan species with spores ornamented by wrappings have traditionally also been assigned to the genus Haplosporidium. Based on the presence of epispore cytoplasm extensions rather than spore wall filaments, the haplosporidan of Teredo spp. can be placed in the genus Minchinia. 相似文献
16.
记述颖蜡蝉科Achilidae广颖蜡蝉属Catonidia 1新种:周氏广颖蜡蝉C. choui sp. nov.,给出了该属物种的名录及分类检索表。模式标本存放于贵州大学昆虫研究所。 相似文献
17.
Han-Zhang Song Serge V. Naugolnykh Xin-Kai Wu Xiao-Yan Liu Jian-Hua Jin 《Plant Diversity》2022,44(6):565
The genus Woodwardia, which together with the genera Anchistea and Lorinseria comprise the subfamily Woodwardioideae of Blechnaceae, has a disjunct distribution across Central and North America, Europe and the temperate to tropical areas of Asia. Fossil records of Woodwardia occur throughout the Paleogene and Neogene of North America, Europe and Asia. However, well-preserved fertile pinna fossils of this genus have not yet been reported in South China. In this paper, a new species, W. changchangensis Naugolnykh et Song, sp. nov. is described from the middle Eocene of the Changchang Basin, Hainan Island, South China. Macromorphological and micromorphological features of the fertile pinna show a straight pinna rachis, alternate, subtriangular pinnules, acute pinnule apices, almost entire or slightly undulate pinnule margins, long-ovoid sori, stalked sporangia and spores with wing-like folds on the surface, which are characterised in detail. Overall, the present fossil is most similar to the extant species Woodwardia japonica, which mostly grows in warm and moist environments. The discovery of this new species from the Changchang Basin of Hainan Island indicates that this genus has been distributed in the low-latitude tropical regions of South China from as early as the middle Eocene. Based on this find, and previous studies of other ferns from the same site, we infer that the climate of the Palaeo-Hainan landscape during deposition of the Changchang Formation was warm and humid, similar to conditions prevailing today across this region. 相似文献
18.
Zixi Wang Fankai Sun Jidong Wang Junling Dong Sanping Xie Mingxuan Sun 《Historical Biology》2013,25(10):1379-1393
AbstractThree species within the genus Calophyllum collected from middle Miocene Fotan Group sediments in Zhangpu County, Fujian, southeastern China are described in this paper. These fossils include Calophyllum zhangpuensis sp. nov., Calophyllum striatum, and Calophyllum suraikholaensis. The new fossil species C. zhangpuensis sp. nov. is oval, possesses entire leaves with closely spaced parallel secondary veins and has a round, or slightly retuse, apex. These specimens represent the first known fossil records of this relative wide leaf-type form of Calophyllum from China and have a length:width (L:W) ratio less than 3:1. In combination with the known modern geographic distribution and habitats of this wide leaf-type Calophyllum and other plants, data suggest that the middle Miocene Fotan flora is indicative of a warm climate. Thus, based on available fossil data, we speculate that this genus probably originated in India during the Paleocene before spreading from India to Bangladesh and into China, Sumatra, Malaysia, Indonesia, and Java during the Neogene, leading to its modern distribution. At least, the 3 fossil species in this region can explain floristic exchange between India, Fujian, and South China, which is consistent with previous studies; the occurrence of these 3 species indicates that Calophyllum began to diversity in China no later than the Miocene. 相似文献
19.
Sterigmatosporidium gen. n. is described as a new basidiomycetous yeast-like fungus with the single species Sterigmatosporidium polymorphum sp. n. for which a Latin diagnosis and a preliminary life cycle are presented. The mean character distinguishing the new genus from the imperfect genus Sterigmatomyces is the development of a dikaryotic mycelium with clamp connections producing sexual spores in ramified whorls and lateral chlamydospores as well as blastospores. The dikaryotic phase could be induced by crossing compatible haploid clones of the heterothallic fungus, which are similar to Sterigmatomyces but not identical with any known species. 相似文献
20.
《Journal of bryology》2013,35(3):210-220
AbstractTwo new species, Ulota yunnanensis and Ulota gigantospora, are described from Yunnan and Sichuan Provinces, China. Both have multicellular spores, a relatively uncommon character in the genus. Differences between the species include growth form and habit, leaf areolation, capsule shape, peristome structure and ornamentation, operculum shape and colour, as well as vaginula and calyptra hairiness. These characters and those discriminating the new species from other ones with similar spore type are discussed and illustrated. 相似文献