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1.
New nymphs of the gryllones insects (Insecta; Gryllones) Iblatta attrepida gen. et sp. nov. (Eoblattida incertae sedis) and Tshekardushka artenatis gen. et sp. nov. (Reculida incertae sedis) from the Lower Permian Chekarda locality (Kungurian Stage of Russia) are described. The nymph of Czekardia blattoides Martynov, 1940 (Eoblattida incertae sedis) from Chekarda is redescribed.  相似文献   

2.
Abstract:  Two new fossil psittaciform birds from the Lower Eocene 'Mo Clay' (Fur Formation) of Denmark ( c . 54 Ma) are described. An unnamed specimen is assigned to the extinct avian family of stem-group parrots, Pseudasturidae (genus and species incertae sedis ), while a second ( Mopsitta tanta gen. et sp. nov.) is the largest fossil parrot yet known. Both specimens are the first fossil records of these birds from Denmark. Although the phylogenetic position of Mopsitta is unclear (it is classified as family incertae sedis ), this form is phylogenetically closer to Recent Pstittacidae than to other known Palaeogene psittaciforms and may, therefore, represent the oldest known crown-group parrot.  相似文献   

3.
Fossil angiospermous stamens with in situ pollen from the Turonian (ca. 90 million years before present, Late Cretaceous) of New Jersey are described and assigned to the Chloranthaceae. The fossil stamens, which are three-parted and bear two bisporangiate thecae on the central lobe and one bisporangiate theca on each lateral lobe, are indistinguishable from stamens of several extant species of Chloranthus. The pollen is spheroidal, 13–18 μm in diameter, with a reticulate exine and apparently elongate/elliptical apertures. The pollen is similar to that in extant Chloranthus in grain size, shape, exine sculpture, and aperture structure. Like pollen of some extant species of Chloranthus, aperture number in the fossil pollen appears to be variable. Because fossil pistillate chloranthoid reproductive structures have not been found at this locality it is unknown whether the fossil stamens described here were borne on the side of the ovary, as in extant Chloranthus, or in another arrangement. The three-parted stamen of Chloranthus is unique in angiosperms and there has been considerable debate concerning the origin and evolutionary significance of the structure. Uncertainty as to whether the three-parted stamen represents a synapomorphy for the genus or a retained plesiomorphy in angiosperms is the primary reason why these fossil stamens are not assigned to the extant genus Chloranthus.  相似文献   

4.
The Aclopinae is a small subfamily within the family Scarabaeidae. It currently comprises five extant genera with 28 species, and eight fossil genera with 25 species. The systematic position of Aclopinae within the family Scarabaeidae is uncertain, particularly because representative species of Aclopinae have been absent in previous phylogenetic studies. Here we performed phylogenetic analyses using morphological and molecular data to investigate the phylogenetic position of fossil and extant Aclopinae. For this objective, we expanded and revised a former morphological data matrix (composed of 68 characters) including all extant genera of Aclopinae. We complemented our morphological investigations with a molecular phylogenetic analysis based on four genes of several extant taxa of Aclopinae and a wide sample of diverse Scarabaeoidea. Our phylogenetic analyses show that all the type species of the fossil genera formerly included within Aclopinae do not belong within the extant Aclopinae clade and support both the exclusion of those fossil taxa and the monophyly of the extant genera of Aclopinae: Aclopus Erichson, Desertaclopus Ocampo & Mondaca, Gracilaclopus Ocampo & Mondaca, Neophanaeognatha Allsopp and Phanaeognatha Hope. Our results also show that the fossil taxa Prophaenognatha robusta Bai et al. and Ceafornotensis archratiras Woolley are closely related to Ochodaeidae, while the remaining type species of fossils formerly included in Aclopinae (Cretaclopus longipes (Ponomarenko), Holcorobeus vittatus Nikritin, Juraclopus rodhendorfi Nikolajev, Mesaclopus mongolicus (Nikolajev), and Mongolrobeus zherikhini Nikolajev) belong to a distinct lineage closely related to Diphyllostomatidae. Based on these results, the subfamily Aclopinae appears monophyletic and sister to the ‘pleurostict’ lineage. Consequently, we propose the following changes to the current classification of the fossil taxa: Holcorobeus monreali (Gómez‐Pallerola) belongs to Carabidae (incertae sedis) as proposed by the original author, and we place Ceafornotensis Woolley, Cretaclopus Nikolajev, Holcorobeus Nikritin, Juraclopus Nikolajev, Mesaclopus Nikolajev, Mongolrobeus Nikolajev and Prophaenognatha Bai et al. in Scarabaeoidea (incertae sedis). Furthermore, we provide an identification key to, and diagnoses of, the genera, illustrations of diagnostic characters and checklists of their included species. The evolutionary perspective presented provides new insights into the evolution of the pleurostict condition in Scarabaeoidea and the biogeography of this group, which is now regarded as Gondwanan, probably evolving during the Cretaceous and not from the upper Jurassic as previously assumed.  相似文献   

5.
The Late Cretaceous record of mammals from India assumes great significance in view of the fact that it is the only Gondwanan landmass that has yielded definitive eutherian mammals. These mammals have variously been assigned to palaeoryctids, archontans or Eutheria incertae sedis. Well preserved lower molars recovered from a new mammal-yielding Deccan intertrappean site near Kisalpuri village, Dindori District, Madhya Pradesh (state), India, are described here under a new species Deccanolestes narmadensis sp. nov. The new fossil material indicates close phylogenetic relationship between Deccanolestes from India and Afrodon (Adapisoriculidae) from the Late Palaeocene of Africa and Europe. In view of older age and more primitive state of Deccanolestes teeth, it is inferred that Deccanolestes represents an ancestral morphotype from which the African/European adapisoriculid Afrodon may have been derived. This is the first compelling terrestrial fossil evidence for an early dispersal between India and Africa. Such a dispersal possibly involved an East African contact with India at the KT transition.  相似文献   

6.
Labyrinth morphology in extant elasmobranchs (neoselachians: sharks, skates and rays) and several extinct chondrichthyans ranging in age from Pliocene to Devonian is investigated using high-resolution computed tomography (CT scanning) and digital reconstitution techniques. The elasmobranch labyrinth is highly specialized toward low-frequency semi-directional sound detection (LFSDP), optimally around 100 Hz. Several features associated with LFSDP in neoselachians also occur in Mesozoic hybodonts (e.g., Egertonodus, Tribodus) and in some incertae sedis extinct sharks (Acronemus, Tristychius), but are absent in osteichthyans, extant and fossil holocephalans, and certain Paleozoic chondrichthyans (ctenacanths, symmoriiforms, Pucapampella). Thus, LFSDP is regarded as an evolutionary novelty of elasmobranchs that arose some time after their divergence from chimaeroids. The suite of characters associated with LFSDP was probably acquired progressively, some characters being more widely distributed among fossil chondrichthyans than others. LFSDP evolved only within chondrichthyans whose otico-occipital fissure became secondarily closed during ontogeny.  相似文献   

7.
The phylogenetic relationships among characids are complex with many genera remaining of uncertain systematic position inside the family. The genus Hollandichthys is one of these problematic genera. It has been considered as incertae sedis inside this family until two recently published phylogenies, one morphological and one molecular, arrived at alternative hypothesizes as to the relationships of Hollandichthys with Pseudochalceus or Rachoviscus, respectively. In this paper, we infer the phylogenetic relations of these taxa based on five genes (three mitochondrial - COI, ND2 and 16S; and two nuclear - Sia and Trop), totaling up to 2719 bp. The 41 analyzed species in the Characidae include four incertae sedis characid taxa once hypothesized as related to Hollandichthys, but never analyzed in a single phylogeny (Rachoviscus, Pseudochalceus, Nematocharax and Hyphessobrycon uruguayensis). Here we propose Rachoviscus as the sister-group of Hollandichthys, grouped in the large clade C previously defined, along with the remaining incertae sedis taxa studied here. In addition, we support the evidence that insemination evolved independently at least three times in the Characidae.  相似文献   

8.
The new species Amplistroma erinaceum, collected on wood of Anacardium excelsum, is characterized by light cream-coloured, rostrate to spinose stromata, and immersed perithecia and long ostiolar necks. Its relationship to other Amplistroma species within the Amplistromataceae (incertae sedis, Ascomycota) are studied based on morphological, cultural, and molecular sequence data of the large subunit ribosomal DNA (28S rDNA).  相似文献   

9.
Synopsis A total of 121 actinistian species belonging to 47 genera and 17 undetermined actinistians is reported from the literature. There are 69 valid species with fair assessment of their phylogenetic position; 21 valid species with poor assessment of their phylogenetic position; 31 actinistian incertae sedis; and 18 taxa that had been identified incorrectly as actinistians or are nomen nuda. The fossil record of the actinistians covers a history of approximately 380 million years. The greatest diversity occurred during the Scythian (Early Triassic).  相似文献   

10.
A fish from the early Oligocene (Rupelian) of Canton Glarus, Switzerland,Cryptobalistes brevis (Rath 1859), until now placed incertae sedis among triacanthoid tetraodontiforms, is shown to be a triacanthid. It is redescribed and compared with the only other known fossil triacanthids, these being the two species ofAcanthopleurus, also from Canton Glarus, and with the seven Recent species of four genera. All of these triacanthids share five derived features. The four Recent genera are in a clade defined by five synapomorphies, andCryptobalistes andAcanthopleurus form an unresolved trichotomy with that clade. Reconstructions of the three fossil species are provided.  相似文献   

11.
We used Cytochrome Oxidase Subunit 1 (COI) to assess the phylogenetic relationships and taxonomy of Nebela sensu stricto and similar taxa (Nebela group, Arcellinida) in order to clarify the taxonomic validity of morphological characters. The COI data not only successfully separated all studied morphospecies but also revealed the existence of several potential cryptic species. The taxonomic implications of the results are: (1) Genus Nebela is paraphyletic and will need to be split into at least two monophyletic assemblages when taxon sampling is further expanded. (2) Genus Quadrulella, one of the few arcellinid genera building its shell from self-secreted siliceous elements, and the mixotrophic Hyalosphenia papilio branch within the Nebela group in agreement with the general morphology of their shell and the presence of an organic rim around the aperture (synapomorphy for Hyalospheniidae). We thus synonymise Hyalospheniidae and Nebelidae. Hyalospheniidae takes precedence and now includes Hyalosphenia, Quadrulella (previously in the Lesquereusiidae) and all Nebelidae with the exception of Argynnia and Physochila. Leptochlamys is Arcellinida incertae sedis. We describe a new genus Padaungiella Lara et Todorov and a new species Nebela meisterfeldi n. sp. Heger et Mitchell and revise the taxonomic position (and rank) of several taxa. These results show that the traditional morphology-based taxonomy underestimates the diversity within the Nebela group, and that phylogenetic relationships are best inferred from shell shape rather than from the material used to build the shell.  相似文献   

12.
A new fossil arachnid,Xenarachne willwerathensis n. gen., n. sp. is described from the Lower Devonian (upper Lower Emsian) Klerf-beds of Willwerath, Germany. This intriguing fossil has a pedicel and pygidium, indicating that it belongs to the tetrapulmonate arachnids, but cannot be referred with confidence to any particular order. It is placed as Tetrapulmonata incertae sedis, though has similarities to whip spiders (Amblypygi) and spiders (Araneae).Xenarachne could even represent a very early spider, though the Devonian arachnid fauna could have included taxa which did not belong in any currently recognised order.Xenarachne may be an example of just such a fossil.  相似文献   

13.
A mandibular specimen from the Bolivian Early Oligocene is provisionally assigned toBranisella boliviana. The crown anatomy of the single preserved tooth, an M2, indicates platyrrhine affinities and several details of the broken jaw are suggestive of symphyseal fusion. Like the African Oligocene parapithecids,Branisella contrasts with extant anthropoids in the relative shallowness of its mandible.Branisella is the most ancient, and seemingly the most primitive, fossil platyrrhine monkey, lacking any of the derived features of the two major clades of modern ceboids. Taxonomically, it is best regarded as family incertae sedis.  相似文献   

14.
中国中、新生代大植物化石新属索引(1865-1990)   总被引:1,自引:1,他引:0  
吴向午 《古生物学报》1993,32(4):495-524
系统地检索1865-1990年的古植物文献,搜录了根据中国材料建立的中、新生代化石属113个,分属于蕨类植物门和种子植物门等.  相似文献   

15.
《Palaeoworld》2022,31(3):443-454
Although liverworts are widely distributed around the world with a large number of extant species, reliable fossil records are relatively rare. Here, we report a new species, Ricciopsis baojishanensis Han and Yan, n. sp. (Ricciaceae) and an unnamed species, Hepaticites sp. from the Late Triassic Nanying’er Formation in Baojishan Basin, Baiyin City, Gansu Province, Northwest China. The generic designation is based on detailed comparison of the gross morphology with related fossil and extant species. The new species is characterized by its rosette-forming thallus, dichotomous branching, ribbon-like segments and entire margins. The current fossils represent the first record of liverwort from the Late Triassic in Baojishan Basin, Gansu Province. Based on the different fossil records of the Ricciaceae, we suggest that these taxa were widely distributed during Late Triassic to Oligocene worldwide, mainly in warm temperate and tropical environments, similar with their current distribution. The discovery of the present fossils indicates that the climate of Baojishan Basin in Late Triassic is warmer and more humid than that of today.  相似文献   

16.
Irregular tube-shaped microfossils incertae sedis are a typical constituent of Late Jurassic shallow-water reefal carbonates of the Northern Calcareous Alps of Austria and are described in open nomenclature. The enigmatic, polymorphous spar-filled tubes with neither observable external nor internal skeletal elements occur either free within peloidal sediments or mostly fixed to skeletal substrates embedded in microbial crusts including the genera Labes Eliášová, Crescentiella Senowbari-Daryan et al . or Isnella Senowbari-Daryan. The tubes are varied in shape and closely resemble different taxa of sponges. As the microbial crusts preferentially occur associated with these tubiform microfossils, this association is suggested to be non-parasitic and mutualistic. Without the surrounding crusts, the existence of these animals would have been masked or perhaps even totally lost in the fossil record expressing the importance of these findings as a characteristic element in the inventory of Late Jurassic reefal biocoenoses.  相似文献   

17.
A fossil leaf compression from the Late Oligocene (28–27 Ma) of northwestern Ethiopia is the earliest record of the African endemic moist tropical forest genus Cola (Malvaceae sensu lato: Sterculioideae). Based on leaf and epidermal morphology, the fossil is considered to be very similar to two extant Guineo-Congolian species but differences warrant designation of a new species. This study also includes a review of the fossil record of Cola, a comprehensive summary of leaf characteristics within several extant species of Cola, Octolobus, and Pterygota, and a brief discussion of the paleogeographic implications of the fossil species affinity and occurrence in Ethiopia.  相似文献   

18.
Three of the subgenera in the sipunculan genus Phascolosoma are reviewed, based on examination of type material. The presumed difference between the subgenera Antillesoma and Rueppellisoma (number of retractor muscles) is shown to be invalid and the taxa are therefore synonymous. The 15 species are either considered junior synonyms of P. antillarum (eight), transferred to other species or genera (six), or considered incertae sedis (one). Phascolosoma antillarum is redescribed. Of the eight species in the subgenus Satonus, only P. pectinatum remains valid: the others are considered either to belong to other taxa (four) or to be incertae sedis (three).  相似文献   

19.
ABSTRACT. Thirty four taxa of heterotrophic protists (amoebae, flagellates and heliozoa) were encountered in cultures established from marine samples from Belize (Central America) and Tenerife (Canary Islands). Most species are flagellates drawn from the choanoflagellates, the cryptophyceans, the euglenids, the kinetoplastids, the bicosoecids, the chromulinids, the pedinellids and a variety of laxa of uncertain affinities (Protista incertae sedis). the identity of the thecate choanoflagellates Salpingoeca ringens Kent, 1880, and S. tuba Kent, 1880, is discussed, and four new species of heterotrophic protists are described: one new species of the amoeba genus Paulinella (Paulinella intermedia n. sp.) and three new species of the incertae sedis genus Luffisphaera Belcher & Swale, 1975 ( Luffisphaera bulbochaete n. sp.; L. longihastis n. sp.; L. turriformis n. sp.).  相似文献   

20.
A new species of Firmiana Marsili is recognized and described based on capsules from the Late Miocene Lincang flora of Yunnan, China. Firmiana yunnanensis nov. sp. is represented by opened, dehiscent, membranous follicles with a weak, sinuous midvein, obtuse secondary veins and thick marginal vein. The follicles conform in shape and venation with those of extant species of Firmiana, a genus now distributed in eastern Africa, Indo-Malaysia, and eastern and southeastern Asia. This fossil species occurred within the native distribution of extant Firmiana species. It provides new information on fossil history, paleoecology, as well as on the plant diversity of the Lincang flora.  相似文献   

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