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1.
Two genera and four species of discosauriscids, Discosauriscus potamites, D. pulcherrimus, Letoverpeton austriacum and L. moravicum , have previously been described from the Boskovice Furrow in Moravia. These laxa were differentiated primarily on the basis of proportional differences of the skull together with other morphological characters.
Excavations at two localities in the Boskovice Furrow have produced new, relatively abundant, skeletal material. The specimens are preserved three-dimensionally. In order to evaluate the differences in skull proportions, 17 variable characters on 70 skulls were measured. Statistical analysis demonstrates the existence of several morphological trends in the shape of the skull. However, no trend permits the division of this set of specimens into two clearly differentiated groups. The morphological differences used previously to define genera and species seem to be incorrect. Pending the discovery of distinct morphological differences, the Moravian discosauriscids can be considered as belonging to only one taxon: Discosauriscus austriacus (Makowsky, 1876).  相似文献   

2.
In this study, a total of 302 adult Anatolian-Ottoman skulls were classified into three morphological forms (dolichocephalic, mesocephalic, brachycephalic), and were examined in order to find the incidence of sutural bones in each forms. In addition, the cranial capacity was measured in the skulls with and without sutural bones. Comparison of the incidence of sutural bones in each form of the skulls, and cranial capacity in skulls with and without sutural bones showed no significant difference. In most populations, the average measure of difference between Anatolian-Ottoman and the others was statistically significant. In conclusion, the incidence of sutural bones is well suited for comperative studies as an anthropological marker or an indicator of population distance. This study was presented in the 3rd National Anatomy Congress (6–9 Sept 1995) Izmir, Türkiye.  相似文献   

3.
Ond?ej Dostál 《Geobios》2009,42(4):495-13629
Two new genera and new species assigned to the family Martynoviidae (Diaphanopterodea), Boskovicia celtai nov. gen., nov. sp. and Moravoptera hladilovae nov. gen., nov. sp. are described and illustrated from the Lower Permian (Artinskian/Sakmarian) locality of Obora, southern Moravia (Czech Republic). Discovery of the species Martynovia insignis Tillyard, originally described from the Lower Permian of Kansas (USA), supports close relationship of both faunas across Euramerica.  相似文献   

4.
5.
117 adult human skulls were classified for three morphological forms, i.e. dolichocephalic, mesocephalic and brachycephalic, and were examined for the presence of sutural bones in each form. Sutural bones occur in each forms of the skulls with no statistically significant differences. This finding is interpreted as indicating that sutural bones are not formed secondary to stress, otherwise the incidence of the sutural bones would have been differed in different morphological forms of skulls.  相似文献   

6.
370 adult crania were examined to find the incidence of sutural bones in Gujarati (Indian) crania and to compare it with other populations to establish the distance between them. The mean measure of difference between Indian and other populations was statistically significant. Comparison of cranial capacity in skulls with and without sutural bones showed no significant difference, and this is interpreted as indicating that sutural bones are not formed secondary to stress.  相似文献   

7.
福建漳平下二叠统的小有孔虫   总被引:9,自引:3,他引:6  
福建漳平岭兜下二叠统地层发育良好,序列清楚,与ting类共生的小有孔虫化石丰富。根据化石群垂直分布特点,可分为三个小有孔虫组合,自下而上为Geintzina-Pachyphloia组合,Langella-Pseudoglandulina longa组合及Hemigordius qinglongensis-Cribrogenerina celebrata组合。这三个小有孔虫组合在福建均属首次发现。这发现为下二叠统的地层时代归属又提供一佐证。  相似文献   

8.
The earliest Permian faunal successions of central Patagonia show compositional changes that probably reflected the environmental warming at the end of the Gondwana glaciations. Bivalves of Asselian to probably Early Tastubian age are described. A new genus,Sueroa, is proposed to reunite a previously known species and a new species,Sueroa andreisi n. sp. Another five new species:Parallelodon? quichaurensis n. sp.,Heteropecten cortignasi n. sp.,Etheripecten saraviae n. sp.,Streblopteria montgomeryi n. sp. andPraeundulomya moreli n. sp. are described. Two previously known species:Malimania patagoniensis (González) andEuchondria sabattiniae González are revised and new occurrences are reported. A further eleven species are described, but they are left in open nomenclature being because they are insufficiently known; these are:Phestia? n. sp.,Modiolus sp.,Palaeoneilo sp.,Stutchburia sp.,Schizodus sp.,Vacunella? sp.,Edmondia sp.,Myonia? n. sp.,Myonia? sp. andPachymyonia? n. sp.  相似文献   

9.
A collection of fossils sampled during the 1898–1902 expedition of theFram to the Canadian Arctic Islands includes abundant bryozoans from the Lower Permian (Artinskian) Great Bear Cape Formation of Ellesmere Island. From this material a new genus with one new species —Nansenopora peculiaris n. gen., n. sp. — as well as three new species —Streblotrypella arctica n. sp.,Phragmophera patricki n. sp. andKallodictyon spinatum n. sp. — are described. Furthermore, the speciesUlrichotrypa ramulosa Bassler, 1929 is reported for the first time from the Lower Permian of the Arctic region.  相似文献   

10.
We describe an arthropod body impression associated with arthropod trackways of the ichnogenus Stiaria from the Lower Permian (upper Wolfcampian) Robledo Mountains Formation (Hueco Group) in the Prehistoric Trackways National Monument of southern New Mexico. The probable producer of these traces was a scorpion, and we name the likely scorpionid resting trace Alacranichnus braddyi, new ichnogenus and ichnospecies. There are no prior reports of scorpionid body impressions from terrestrial settings in the fossil record.  相似文献   

11.
Two localities in the Boskovice Furrow region of Moravia (Czecho-Slovakia) have produced new, well preserved material of the Lower Permian tetrapodDiscosauriscus austriacus (Makowsky 1876). A relatively large number of specimens have been found with some dermal skull roof bones partly or fully subdivided, and/or fused. These are the first records of such subdivisions and fusions in this tetrapod and the following bones are discussed: frontal, postfrontal, parietal, intertemporal, supratemporal, tabular and postparietal. The subdivided bones within the skull roof ofDiscosauriscus (and some dissorophoids) are situated at the same places as those found in Devonian rhipidistians, and may relate to the homology of the bones of the cranial exoskeletal roof inDiscosauriscus and in osteolepiforms. It shows that the “orthodox” terminology of the skull roof bones used in osteolepiforms is correct.  相似文献   

12.
Fossilised traces of swimming amphibians, assigned to Batrachichnus delicatulus and Serpentichnus robledoensis igen. et isp. nov., are described from the Lower Permian of the Robledo Mountains, southern New Mexico. The B. delicatulus specimen is interpreted as a trackway of a small 'amphibian' (temnospondyl, nectridean, microsaur or juvenile embolomere) swimming straight ahead. S. robledoensis consists of repeated pes imprints separated by discontinuous, L-shaped imprints (body traces). It is interpreted as a trackway of an 'amphibian' swimming in a similar manner to the motion of a side-winding snake. The producer of S. robledoensis is more distinctive than in B. delicatulus , and is suggestive of the lysorophian Brachydectes . This is the first locomotory trace to be assigned to this 'amphibian' group.  相似文献   

13.
Until now, the largest specimens ofDiscosauriscus (and alsoUtegenia andAriekanerpeton- the Lower Permian members of the family Discosauriscidae) have been considered to be adult individuals. The largest specimens ofDiscosauriscus, in which the external gills are still present, had skull lengths of about 22-25 mm. Metamorphosis was believed to have commenced at this size in discosauriscids and specimens with skull lengths of about 50-54 mm were considered to be already adult or senile. New finds ofDiscosauriscus demonstrate the presence of external gills in specimens with skull lengths of up to 32 mm. On the base of this, together with the ornamentation or the skull roof bones and osteological features of new large specimens, it is here concluded that 1)Discosauriscus represents the larval, metamorphic and early juvenile stages of a reptiliomorph tetrapod, the adults of which are yet unknown and 2) two other discosauriscids(Ariekanerpeton andUtegenia) also represent early ontogenetic stages.  相似文献   

14.
Apsisaurus witteri (gen. et sp. nov. . from the Lower Permian of Texas is identified as a diapsid, based on the presence of both a lateral temporal fenestra and a suborbital fenestra. Derived characters shared with neodiapsids but not with araeoscelidians suggest that Apsisaurus is more closely related to modern diapsids than to araeoscelidians. A phylogenetic analysis suggests that younginiforms are not part of the crown group of diapsids.  相似文献   

15.
Recent investigation on the Cathaysian flora of the Lower Permian Taiyuan Formation in Hebei Province, North China has led to the discovery of a new type of fern, Rastropteris pingquanensis gen. et sp. nov. Preserved as a permineralization, the stem, with a mantle of petiole bases and roots, shows a unique combination of anatomical characters. The vascular strand consists of a solid protostele with uniformly elongated tracheids and mesarch maturation of the xylem. In transverse section, the configuration of leaf trace xylem changes from reniform endarch to a tangentially elongated strand adaxially recurved at each end with several adaxial ridges. Stem and petiole cortex contains abundant sclerotic tissue with an interstitial tissue developed within the mantle of petiole bases and roots. A reinvestigation of Grammatopteris rigollotii , from the Permian of France, the type species of the genus allows interpretation of the latter as closer to Rastropteris than any other fern. Both taxa are provisionally reported to an incertae sedis group of filicalean ferns possibly involved in the origin of Osmundaceae.  相似文献   

16.
New taxa of detached seeds are described from the Kungurian (Lower Permian) of the Middle Cis-Urals: Laevigatospermum compressum gen. et sp. nov., Hirsutospermum paniculatum gen. et sp. nov., Rugosospermum callosum gen. et sp. nov., and Craspedosperma filiferum sp. nov. The systematic position of the new taxa is discussed.  相似文献   

17.
Carboniferous to Permian marine stromatolites are widely dispersed across the Pangaean margins and embayments and are typified by the ‘Ottonosia-grade stromatolite’ (designated herein). This stromatolite type consists of a well-laminated oncoid or domical stromatoid that developed into branching, laminated columns in the upper reaches. To develop a model for the global pattern, we investigated Lower Permian stromatolites from Kansas (Howe Limestone Member, Red Eagle Limestone). Stromatoids from the Lyon County locality typify the Ottonosia-grade stromatolites. The laminae are sharp throughout the stromatoid and are defined by an increase in cornuspirid foraminfera and algal filaments. The upper zone of the stromatoid is composed of well-laminated branching and brecciated columns (‘pseudo-thrombolitic’). Coeval stromatolites from a new exposure at the Tuttle Creek Dam spillway possess a more massive mesostructure. These stromatolites are composed of a turbinate stromatoid or oncoid base and an overlying domical stromatoid, and are rimmed by smaller meandering columns. Only the basal stromatoid, oncoids, and upper columns are well laminated. In both localities, the microbial-constructing ecosystem is dominated by cornuspirids and calcifying filamentous algae (?Girvanella). The mesostructural differences of the stromatolites are due to different environments of formation. The Tuttle Creek stromatolites formed in a shallow-subtidal to intertidal open marine setting. The coeval Lyon County stromatolites formed in a semi-restricted, marginal marine environment such as a lagoon or supratidal zone. Based on this information and independent sedimentological data, we conclude that lagoonal or supratidal zones were common features in the late Paleozoic intracratonal zones of the Pangaean supercontinent and account for Ottonosia-grade stromatolites occurring in the Laurentian mid-continent, the Zechstein Basin, Japan, Brazil, and Tunisia.  相似文献   

18.
This paper deals with the Fossil Plants from Upper Permian in Northern Xinjiang. These plants include 25 species of 15 Genus. Five new species is all described in this paper. These are: ?Supaia serrata sp. nov. Tychtopteris densinervis sp. nov., Ty. obesa sp. nov., Comia Cangfanggouensis sp. nov. and Lepeophyllum ovatum sp. nov. These are all new to science, found in the Lower Cangfanggou Group in Northern Xinjian, of Late Permian in age. Some fossils Lobatannularia multifolia Ken'no, Sphenopteris rotunda Sze and Alethopteris huiana Lee found in this group are known in the Cathaysian Flora. Others are common in the Angara Flora, such as Stellotheca sehtchurowskii (Schmal.) Surange et Prakash, Sphenopteris, adzvensis Zal., Tychtopteris cuneata (Schmal.) Zal. Noeggerathiopsis sp., ect. That indicates in the Lower Cangfanggou Group is a transitional zone between the Angara and the Cathaysian floras.  相似文献   

19.
The A-mode sutural ontogeny in prolecanitid ammonoids   总被引:1,自引:0,他引:1  
The generally accepted theory of a U-mode sutural ontogeny of prolecanitid ammonoids and their descendants is refuted. The basic suture formula of the order Prolecanitida is E A L U I (not E L U2 U1 I), resembling that of derived members of the suborder Tornoceratina (their phylogenetic ancestors), and of the suborder Goniatitina. During phylogeny of the prolecanitids, secondary umbilical lobes are introduced and lead to multilobate forms. In early ceratites, the original L lobe disappeared, and an increase in sutural elements took place by the introduction of supplementary U lobes. Consequently, sutural nomenclature of Permian ceratites and Mesozoic ammonoids has to be modified.  相似文献   

20.
Distribution of members of the thermophilic genus Pteronites in the Upper Paleozoic beds of northeastern Asia is briefly considered. A new species, Pteronites magnus sp. nov., from the Lower Permian of the Omolon Massif is described.  相似文献   

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