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1.
Abstract. Tertiapatus dominicanus n.g., n.sp. (Tertiapatidae n.fam.) and Succinipatopsis balticus n.gen., n.sp. (Succinipatopsidae n.fam.) (Lobopodia: Onychophora), the first Tertiary fossils of the Lobopodia, are described from Dominican and Baltic amber, respectively. Both families are characterized by the presence of simple legs lacking foot portions with claws and pads. Tertiapatidae is further characterized by soluble body pigments and oral papillae shorter than the legs. Succinipatopsidae is characterized by non-soluble body pigments and oral papillae longer than the legs. Nomenclatural changes include the erection of the class Udeonychophora n. nom. for terrestrial onychophorans with a ventral mouth, the order Ontonychophora n.nom. for extant onychophorans possessing legs with a differentiated "foot" portion, and the family Helenodoridae n.nom. for the genus Helenodora from the Carboniferous. The biogeographical significance of these fossils and their phylogenetic relationship with previously described onychophorans are discussed. 相似文献
2.
The ichnological record provides valuable information on the lifestyle, behaviour, and other palaeobiological and palaeoecological aspects of the biota. Here, we describe an interesting case of bioerosion trace fossils in bones of Buitreraptor gonzalezorum Makovicky, Apesteguía and Agnolín, 2005, a deinonychosaurian theropod from the fossiliferous locality of La Buitrera, Río Negro, Patagonia, Argentina. The trace fossils are morphologically diverse and preserved in a great percentage of the skeleton, including the jaw, vertebrae and limbs. Four main groups of trace fossils have been informally named as Parallel-Edge Furrows, Overlapped Grooves, Punctures and Lined. Parallel-Edge Furrows are in turn subdivided into four subgroups: isolated furrows, parallel pairs, opposed pairs and a combination of parallel and opposed pairs. The bioerosion trace fossils were probably generated by scavenging activities, and the semi-articulated preservation of the skeleton and the small size of each individual trace indicate small-sized tracemakers. Mammals are the main candidates although some traces may have been generated by crocodyliforms and insects such as dermestids and termites. This evidence provides additional information about palaeoenvironmental conditions, taphonomic processes, taxonomic diversity and ecological relationships that characterised this part of northern Patagonia at Early Cretaceous times. 相似文献
3.
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
4.
A new genus and species of belid weevils, Pleurambus strongylus Poinar and Legalov, n. gen., n. sp. (Coleoptera: Belidae) in the tribe Allocorynini is described from Dominican amber. Belid fossils are quite rare and the new species is the first fossil member of the family from the Neotropics. This discovery suggests that belid diversity in Hispaniola during the Tertiary was higher than at present since no extant belids have been reported from the West Indies.http://www.zoobank.org/urn:lsid:zoobank.org:pub:DF79FF39-634D-4BD7-AD0B-F5FB3BBE1081 相似文献
5.
Abstract The fossil history of leaf beetles (Chrysomelidae) is relatively poorly documented despite an abundance of available material. Of particular interest is the origin and radiation of the diverse tortoise beetles, a derived group within Cassidinae s.l. (=Cassidinae + Hispinae) defined by the exophagous life history and specialized morphology of the immature stages. Cassidinae is also a group with relatively few fossil records that can be assigned with any degree of certainty. Here we report two of the oldest definitive tortoise beetle fossils, Eosacantha delocranioides gen.n. et sp.n. and Denaeaspis chelonopsis gen.n. et sp.n. , from the Eocene Green River Formation (ca. 47 million years old) in northwestern Colorado, U.S.A. Owing to the fine level of preservation, many important features can be observed and are coded into the recent cladistic analysis for the subfamily. Phylogenetic analysis highlights that both genera have affinities with modern lineages, one restricted to the Old World and the other restricted to the Neotropics. Although Cassidinae as a whole extend into the Cretaceous, the available information suggests that the tortoise beetles perhaps originated and diversified during the Early Tertiary. As such, the morphological and biological transitions from the leaf‐mining hispiforms to the distinctive tortoise‐like cassidiforms, with their elaborate defensive larval shields and other unique behaviours, probably took place during the latest Paleocene or earliest Eocene. These Green River fossils are the oldest yet to document the specialized morphology associated with the transition in cassidine feeding and immature biology. 相似文献
6.
J. Mariaux 《Systematic parasitology》1991,18(3):187-191
Yapolepis yapolepis n. g., n. sp. a parasite of the icterine greenbul Phyllastrephus icterinus (Aves: Pycnonotidae) in the Ivory Coast is described. Due mainly to the lack of both a rostellar pouch and a paruterine organ, this new genus is classified within the family Metadilepididae Spassky, 1959. Yapolepis is principally characterised by its unarmed rostellum and by unilateral genital pores. It is assumed that the Metadilepididae are probably more diversified than presently known, the reason for this being our limited knowledge of the parasite-fauna of the intertropical terrestrial birds which are their main hosts.This work is part of the author's thesis. 相似文献
7.
Gudrun Daxner-Höck 《Pal?ontologische Zeitschrift》2000,74(1-2):215-225
The smallest and most primitive Oligocene cricetid,Ulaancricetodon badamae n. gen., n. sp. is described from the Hsanda Gol Formation in Mongolia. The fossils were recovered from stratified fossil horizons immediately below and above a basalt layer dated at 31.5 Ma (40Ar/39Ar-data), that is an Early Oligocene age. Although the dental formula is muroid (1-0-0-3/1-0-0-3), the tooth morphology and tooth size ofUlaancricetodon badamae n. gen., n. sp. point to a close relationship with the zapodidHeosminthus Wang 1985, which is known from the Asian Late Eocene to Early Oligocene. 相似文献
8.
SYNOPSIS. Toxoplasma ranae sp. n. is described from the brain of a leopard frog, Rana pipiens, probably from Mexico. Its pseudocysts were 72(55-106) × 48(29-70) μm in fixed sections. They contained an average of ~ 4,000 slightly curved elongate zoites measuring 4–5 × 0.5 μm, with a central, spherical, vesicular nucleus. 相似文献
9.
Three wasp (Hymenoptera: Vespidae) fossils in Cretaceous amber (Late Albian) of northern Myanmar are described. Two are new species of the Mesozoic genus Curiosivespa (Rasnitsyn): C. zigrasi sp.n. and C. striata sp.n. The third species, Protovespa haxairei gen.n. et sp.n. , has a combination of features unique among Mesozoic Priorvespinae and the extant subfamilies. These well preserved fossils provide new morphological data for a cladistic analysis of the basal lineages of Vespidae. Results suggest that Euparagiinae is the sister group of all other Vespidae. The new genus Protovespa appears more closely related to extant Masarinae, Eumeninae and social wasps than to Priorvespinae. We assign it to a new subfamily: Protovespinae. Finally, fossil information combined with a phylogenetic tree shows that the main groups of Vespidae probably evolved during the Early Cretaceous. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:1E7E4796‐6E70‐4D81‐BB34‐0FEEA765DC25 . 相似文献
10.
Blanka Pacltová 《Origins of life and evolution of the biosphere》1977,8(2):155-168
Large amounts of well preserved microfossils have been reported from the cherts of the Upper Proterozoic of the Bohemian Massif (Middle Europe). They resemble those described by Cayeux (1894) from the Upper Proterozoic (Brioverian) of Bretagne (France). It is shown, unlike the views of Cayeux and his followers (Deflandre, 1955, and Graindor 1957), that the observed structures did not belong to individuals but to colonies of filamentous prokaryotic organisms, most probably blue-green algae (Cyanophyta). These produced specific crystal-like mineral aggregation round each filament. Scanning microscope examination has revealed that the individual facets of these mineral crystals were perforated by the openings through which the thread-like bodies of these primitive organisms protruded. It is shown that these microorganisms were attached to the cells of other, bigger microorganisms and enveloped them. Some of these substrate organisms might have been eukaryotic algae. The thecae gradually accumulated around the cells of these carrier organisms and after death the colonies disintegrated to constitute the main component of the sediment. The microfossils described are just a major component of a complicated fossil assemblage comprising coccoid and filamentous blue-green algae and bacteria. There are indications that several eukaryotic species might also have been present.The following new taxa are described:Thecophytales, new order,Cayeuxidae (Graindor) family emend.,Bohemipora n. gen.,B. pragensis, n. sp. 相似文献
11.
STIAN NYLUND ARE NYLUND KUNINORI WATANABE CARL E. ARNESEN EGIL KARLSBAKK 《The Journal of eukaryotic microbiology》2010,57(2):95-114
ABSTRACT. Paranucleospora theridion n. gen, n. sp., infecting both Atlantic salmon (Salmo salar) and its copepod parasite Lepeophtheirus salmonis is described. The microsporidian exhibits nuclei in diplokaryotic arrangement during all known life‐cycle stages in salmon, but only in the merogonal stages and early sporogonal stage in salmon lice. All developmental stages of P. theridion are in direct contact with the host cell cytoplasm or nucleoplasm. In salmon, two developmental cycles were observed, producing spores in the cytoplasm of phagocytes or epidermal cells (Cycle‐I) and in the nuclei of epidermal cells (Cycle‐II), respectively. Cycle‐I spores are small and thin walled with a short polar tube, and are believed to be autoinfective. The larger oval intranuclear Cycle‐II spores have a thick endospore and a longer polar tube, and are probably responsible for transmission from salmon to L. salmonis. Parasite development in the salmon louse occurs in several different cell types that may be extremely hypertrophied due to P. theridion proliferation. Diplokaryotic merogony precedes monokaryotic sporogony. The rounded spores produced are comparable to the intranuclear spores in the salmon in most aspects, and likely transmit the infection to salmon. Phylogenetic analysis of P. theridion partial rDNA sequences place the parasite in a position between Nucleospora salmonis and Enterocytozoon bieneusi. Based on characteristics of the morphology, unique development involving a vertebrate fish as well as a crustacean ectoparasite host, and the results of the phylogenetic analyses it is suggested that P. theridion should be given status as a new species in a new genus. 相似文献
12.
SYNOPSIS. Haemogregarina faiyumensis n. sp., a parasite of toads, Bufo regularis, in Faiyuni Province, Egypt, U.A.R., is described. In a survey of 689 toads from various localities in Cairo, Giza and Faiyurn provinces, only 3 out of 13 toads from Kom O Shim near Faiyum were infected. This species, known only by blood forms (most probably gametocytes) of two different staining reactions, is 13-17 μ long and 4-5 μ wide, with an average of 15.5 × 4.5 μ. The nucleus is typically subcircular and 3-5 × 3–5 μ, with an average of 4.5 × 3.9 μ. 相似文献
13.
Riserius pugetensis gen. n., sp. n. (Nemertina: Anopla), a new mesopsammic species,and comments on phylogenetics of some anoplan characters 总被引:1,自引:0,他引:1
Jon L. Norenburg 《Hydrobiologia》1993,266(1-3):203-218
Riserius pugetensis gen. n., sp. n. is described from the northwest coast of Washington, U.S.A. It is probably a heteronemertine and, as such,
would be the first known mesopsammic member of that order; it lives in the interstices of medium to coarse, moderately clean
sands. Its morphology presents some attributes considered characteristic of mesopsammic fauna. The effect of some of these
attributes is a generalized appearance of anatomical ‘simplicity’ and, as with other mesopsammic metazoans, this presents
difficulties in distinguishing between primitiveness and reduction. In the new species such problematic features include the
lack of subepidermal glandular cells and connective tissue, reduced proboscideal musculature, simple blood-vascular system,
and the presence of a ‘secondary’, outer circular musculature in the body wall. The general appearance of this new species
is very similar to the so-called palaeonemertine Hubrechtella and characteristics of both suggest relationship with the baseodiscid heteronemertines. These relationships are explored
in light of a modified interpretation of proboscideal musculature, a traditional cornerstone of heteronemertmean taxonomy. 相似文献
14.
Summary A study of fossils in thin sections of a sample from the uppermost Krol E Member in the Mussoorie Hills of the Lesser Himalaya,
India, proves the existence of morphologically differentiated calcified sponges within the Precambrian-Cambrian boundary time
interval. The sponges, described as Mussooriella kroli n.g., n.sp. and Maldeotaina composita n.g., n.sp. indicate the presence of different organization grades at the Precambrian-Cambrian interval. Mussooriella had a calcareous skeleton consisting of skeletal elements composed of an inner laminated part and a distinct peripheral layer
with knobs. Maldeotaina is characterized by a stromatoporoid-grade growth pattern following a thalamid-grade pattern. The stromatoporoidgrade part
of the skeletons reminds strongly on skeletal elements common in labechiid Ordovician and younger stromatoporoids. Maldeotaina also shows criteria of Early Cambrian fossils, originally described as stromatoporoids and later excluded from this group
and transferred to archaeocyaths. These similarities point to an Early Cambrian age of the fossil-bearing horizon in the topmost
Krol E Member. Growth cavities with crypts indicate that the sponges might have contributed to the formation of small metazoan
reefs-like structures.
Although the study is based on limited material and many interpretations are still tentative, a thorough documentation of
the preliminary results seems reliable considering the high potential of the fossils of the upper Krol Formation important
source in understanding of early metazoan differentiation. 相似文献
15.
NORMAN D. LEVINE 《The Journal of eukaryotic microbiology》1979,26(2):167-168
Agamococcidiorida ord. n. and Rhytidocystidae fam. n. are established in the apicomplexan subclass Coccidiasina for the genus Rhytidocystis Henneguy, 1907. Dehornia Porchet-Henneré, 1972 is synonymized with Rhytidocystis. 相似文献
16.
JOHN W. FOURNIE WILLIAM E. HAWKINS ROBIN M. OVERSTREET 《The Journal of eukaryotic microbiology》1985,32(3):542-547
Oocysts of Calyptospora empristica n. sp., the second described species in its genus, are described from the freshwater starhead topminnow, Fundulus notti, in southern Mississippi. Oocysts are 22 μm in diameter with a wall about 20 nm thick and have no residuum, micropyle, or polar granule. Sporocysts are spheroid, 9 × 5 μm with a two-layered wall approximately 120 nm thick. They have an oblong apical opening at the anterior pole, a single ornamented sporopodium approximately 5.7 μm long at the posterior pole, and a residuum. An intermediate host, most likely the freshwater grass shrimp Palaemonetes kadiakensis, is probably required to complete the life cycle. 相似文献
17.
JORDI M. DE GIBERT GUILLEM MAS ALLAN A. EKDALE 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(4):574-585
Gibert, J.M. de, Mas, G. & Ekdale, A.A. 2012: Architectural complexity of marine crustacean burrows: unusual helical trace fossils from the Miocene of Mallorca, Spain. Lethaia, Vol. 45, pp. 574–585. Unusual helical trace fossils occur in Tortonian shelfal calcarenites in the island of Mallorca. Their morphology may be either simple (ichnogenus Gyrolithes) or, more commonly, consist of two concentric helical burrows (ichnogenus Lapispira). They bear a very characteristic pelleted lining and are associated and probably connected to Thalassinoides and Ophiomorpha burrow systems very abundant in the same unit. These features allow the interpretation that the tracemaker was a thalassinidean shrimp. The complex and compound nature of these trace fossils is comparable to that seen in other modern and fossil crustacean burrow systems, and it reflects the behavioural plasticity of the architects. □Trace fossils, ichnology, ichnofabrics, crustacean burrows, Miocene, shallow marine, Lapispira. 相似文献
18.
V. Negri F. Veronesi 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1989,78(3):400-404
Summary Crosses between male sterile L. corniculatus (2n=4x=24) and L. tenuis (2n=2x=12) plants were performed in order to verify the presence of 2n gametes in L. tenuis. All but one of the plants from these crosses had 2n=4x=24 and the L. corniculatus phenotype; this plant had 2n=2x=12 and the L. tenuis phenotype. The plants also showed good quantity of pollen at tripping, good pollen fertility and good percentage of seed setting in the backcross to L. corniculatus. On the whole, both cytological and morphological observations, showing that all but one of the plants from L. corniculatus x L. tenuis were normal tetraploids, suggest the existence of diploandrous gametes in L. tenuis. On the other hand, haploid parthenogenesis probably gave origin to the dihaploid plant 2n=2x=12. 相似文献
19.
ABSTRACT. Based on both morphological and molecular information, two new euplotid genera Apodiophrys n. g. and Heterodiophrys n. g. are described in the present paper. Apodiophrys n. g. is defined as sculptured Diophryinae with bipartite adoral zone; frontoventral cirri arranged in Diophrys‐pattern; marginal cirri located in two clearly separated groups. Heterodiophrys n. g. is recognizable by the combination of Diophrys‐like frontoventral cirri and the unique structure of several marginal cirri that are arranged in a long row. The type species for both new genera, Apodiophrys ovalis n. sp. and Heterodiophrys zhui n. sp., collected from southern China sea, are described. The small subunit rRNA (SSU rRNA) gene sequences for both new taxa are determined. Phylogenetic analyses based on these data indicate that Apodiophrys is most closely related to Paradiophrys, which then clusters with Uronychia species. Thus, Apodiophrys–Paradiophrys is separated from other typical Diophrys‐like genera in the SSU rRNA gene trees. The new genus Heterodiophrys is basal to the sister group of Diophrys–Diophryopsis, hence belongs to the “core”Diophrys‐complex. 相似文献
20.
Trace fossils of the arthropod Camptophyllia from the Westphalian (Carboniferous) rocks of Lancashire, UK and their palaeoenvironmental context 总被引:1,自引:1,他引:0
John Pollard Paul Selden Stephen Watts 《Palaeogeography, Palaeoclimatology, Palaeoecology》2008,270(3-4):399
Two arthropod trace fossils are described and analysed from the Carboniferous Lower Westphalian (C. communis and basal A. modiolaris chronozones) coal-bearing strata of Lancashire. The biserial trackway Diplichnites triassicus consists of five overlapping en echelon sets of 7–9 tracks preserved as epichnia and hypichnia in lacustrine siltstones. The trackway suggests subaqueous in-phase walking by a multi-segmented producer with a body length of 35–40 mm, width 17–22 mm, and 7–9 appendages. Curved, clustered, or laterally repeated, hypichnial lobes with transverse striations on the base of ripple cross-laminated sandstone are identified as Rusophycus versans. This trace fossil is interpreted as shallow resting or furrowing burrows of a homopodous arthropod, 30–60 mm long, 15–30 mm wide, and probably the same kind of arthropod as produced D. triassicus.A review of contemporary arthropod body fossils from Lagerstätten in Lancashire favours the onisciform, or Arthropleura like arthropod Camptophyllia as a potential producer of both of these trace fossils in a lacustrine palaeoenvironment.This study integrates the analysis of sediments, trace fossils and body fossils for reconstructing the arthropod biota and ecology in Westphalian lacustrine and crevasse splay fluvial palaeoenvironments. 相似文献