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1.
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   

2.
Sebastian G. Dalman 《Ichnos》2015,22(3-4):177-182
Cheliceratichnus lockleyi ichnogen. nov. et ichnosp. nov. is a new ichnotaxon of arthropod resting trace (cubichnium) from the Lower Jurassic (Hettangian) East Berlin Formation in Holyoke, Massachusetts, USA. The trace fossil is preserved as showing many of the external anatomical features of the exoskeleton, which resemble those of some chelicerates, notably sun spiders (Solifugae). The resting trace is directly associated with a trackway of the ichnospecies Acanthichnus cursorius Hitchcock. This is the first described fossil resting trace of a solifugan-like arthropod, and the first direct evidence of a trackmaker of A. cursorius.  相似文献   

3.
内蒙古早三叠世的Scalaroxylon及其演化意义   总被引:2,自引:0,他引:2  
描述产于内蒙古下三叠统老龙头组木化石梯纹木属的一个新种ScalaroxylonjalaidqienseZhangetZhengsp.nov.及一个新联合种S.multiforium(ZhengetZhang)ZhangetZhengcomb.nov.。Scalaroxylon原产于德国上三叠统考依波层,当前报道的产自内蒙古的新材料是该类型化石在中国的首次发现。该属以次生木质部为代表,生长轮不存在,它的主要特征是管胞径向壁纹孔全为梯纹纹孔;木射线1至多列,异形;射线细胞的水平壁无孔,端壁通常具孔,弦向壁多数具孔。根据次生木质部管胞的纹孔类型和木射线构造特征对该属在植物系统演化上的意义进行了初步探讨,认为它代表了种子蕨类到苏铁类之间的中间环节。  相似文献   

4.
Abstract:  Abundant and diverse bioerosion trace fossils in the Lower Devonian of the Rade de Brest, France, were produced by boring ctenostomate bryozoans, polychaete annelids and algae. Two unidentifiable traces of encrusting sclerobionts are also considered. Two new taxa are described: Pinaceocladichnus cristatus ichnosp. nov. and Ichnogutta erectus ichnogen. et ichnosp. nov. Both are attributed to the work of boring bryozoans. Sedimentary condensation during intervals of sea-level rise seems to have had an important influence in promoting infestation by organisms, the activities of which are now preserved as trace fossils. A zonation of bioerosion trace fossils within the offshore zone, in the Lower Devonian of the Armorican Massif, is also suggested.  相似文献   

5.
We describe a recently discovered trace fossil from a eurypterid Konservat‐Lagerstätte in the upper Silurian Tonoloway Formation of Pennsylvania, and formally describe contemporaneous traces from the Williamsville Formation Lagerstätte of Ontario. The traces from both localities are assigned here to Arcuites bertiensis igen. et isp. nov. Based on comparisons with previously described eurypterid trackways, neoichnological experiments, and the co‐occurrence with eurypterid remains, Arcuites is interpreted as having been made by the swimming leg (sixth prosomal appendage) of swimming juvenile to adult eurypteroid eurypterids, and represents the first unambiguous trace fossil evidence for eurypterid swimming behaviour. The morphology of Arcuites indicates that eurypteroid eurypterids swam using drag‐based rowing, whereby the animal propelled itself forward by moving its oar blade‐like swimming paddles in an in‐phase backstroke. Arcuites morphology also indicates that the eurypteroid swimming appendage had a greater degree of movement than was previously suggested, and a revised rowing model is proposed. Differences in the abundance of A. bertiensis in the Tonoloway and Williamsville formations suggest a bathymetric control on eurypterid swimming behaviour and trace production. The association of Arcuites with eurypterid body fossils in both units indicates that these Lagerstätten were autochthonous assemblages and provides additional evidence for eurypterid inhabitation of shallow subtidal marine environments in the late Silurian.  相似文献   

6.
The fish swimming trace Undichna unisulca is reported from a sandstone block collected from the Upper Silurian (Ludlow) Burgsvik Formation of Gotland, Sweden. It represents the oldest record of a vertebrate trace (apart from coprolites), predating previous finds from the Lower Devonian by at least 10 Ma. A thelodont or acanthodian fish may have produced the sinusoidal trails with the aid of their caudal or anal fins while browsing slowly over the sediment whilst searching for food.  相似文献   

7.
Jesús Reolid 《Ichnos》2017,24(3):222-233
Twenty-six enigmatic footprints composed of three elongated parallel depressions (two lateral ones and a shorter central one located forward with respect to the others) are described from Middle Triassic red beds of the Tabular Cover in southern Spain. The purpose of this work is the interpretation of these enigmatic tracks. The footprints range from 28 to 48 cm in length and 23 to 44 cm in width. Limestones on top of the footprint-bearing sandstone contain invertebrate traces such as Planolites, Thalassinoides, and Rhizocorallium, and bivalves (Pleuromya, Trigonodus, and Unionites), typical of marine and brackish environments. They indicate that these footprints developed in a coastal or nearly coastal environment. Whereas the enigmatic trace fossils correspond to tridactyl footprints, the digital marks are parallel and do not show any divarication as in typical walking footprints of archosauria. These traces were left when the trackmaker was swimming in a waterbody deep enough for floating only occasionally touching the ground with the digit tips. The tracks formed as a result of the backward sweeping of the tips when the digits came in contact with the bottom while the animal was buoyed by water. They differ from typical swim traces of other archosaurs (such as theropods) that show three longitudinal scratches because in studied tracks the axial digit (III) of the bipedal tridactyl archosaur sinks in the sediment and gives a short and deep scratch. The other digit scratches (from digits II and IV) would correspond to the upper surface of the toes. The studied tracks correspond to Characichnos ichnofacies (swimming tracks composed by parallel scratch marks) and they were made by a bipedal tridactil archosaur or some functionally tridactyl, chirothere tracemaker.  相似文献   

8.
9.
The trace fossil Zoophycos is abundant in the shallow‐marine deposits (tempestites) of the Lower Devonian (Emsian) Yangmaba Formation in Ganxi of Sichuan, South China. It often occurs as part of complex trace fossils that comprise different integrated elements: scratch traces, simple to complex spreiten structures with marginal tubes (Zoophycos) and vertical tunnels. The complex Zoophycos burrows consist of spreiten with a marginal tube, preserved as convex hyporeliefs on the sole of an erosion surface. The exquisite, complex spreiten are interpreted to have been formed by deposit‐feeding behaviour, where the animal constructed the trace upwards without leaving faeces in the spreiten. The width of the marginal tube in different whorls is almost constant. The scratches are observed on the wall of the marginal tubes. The Zoophycos intergrades with Spongeliomorpha and Chondrites and was later cut by vertical shafts. All these features together indicate that the Zoophycos‐maker might have been a vermiform polychaete instead of a predator such as a decapod crustacean (Spongeliomorpha producer). Based on stratigraphical and ichnological features, the complex trace fossils resulted from the complex activity of different opportunistic organisms (r‐strategist) that quickly occupied and thrived within the quiet, nutrient‐rich environment after storm events.  相似文献   

10.
Weitschataster intermedius gen. et sp. nov., is described from the Upper Campanian (Upper Cretaceous) of Hannover (Lower Saxony, N Germany). The new species is characterized by its conspicuous rimmed pedicellariae scars covering almost the complete actinal surface and by small body size. W. intermedius represents a transitional state between W. decipiens comb. nov. from the Lower Campanian and the well-known W. undulatus comb. nov. from the Lower Maastrichtian of NW Europe. Among Spencer’s types of W. undulatus, one paratype is recognized as belonging to the genus Parametopaster.  相似文献   

11.
A complex microboring trace of fungal affinity is described in shells as a new ichnotaxon Saccomorpha stereodiktyon isp. nov. and compared with the earlier established ichnotaxon Saccomorpha terminalis Radtke, 1991. The new trace is characterized by a three-dimensional network of tunnels composed of a bifurcate horizontal (parallel to substrate surface) network with an upright (perpendicular to surface) system of tunnels and by the formation of cylindrical to multilobate terminal sporangial swellings. The new trace shares with Saccomorpha terminalis Radtke, 1991 the terminal position of sporangial swellings but differs from this ichnotaxon by its complexity in spatial arrangement, segmented construction, and ramification of tunnels. The horizontal parts of the network in the new taxon adhere to the substrate surface and regularly produce thinner tunnels that explore the interior of the substrate, allowing the producer to participate in digestion of organic lamellae incorporated in the shell. Microborings similar to the new trace fossil have been observed in modern bivalve shells of the Atlantic Ocean, North Sea, Adriatic Sea and Red Sea at depths ranging from the intertidal down to 1,550 m. The fossil record of the trace reaches back to the Jurassic and the type material stems from a Lower Oligocene oyster shell. The study shows that complex microboring traces reflect both behaviour and developmental strategy of their makers.  相似文献   

12.
河南叶县下寒武统辛集组单板类和腹足类化石的研究   总被引:5,自引:3,他引:5  
本文描述和讨论了河南叶县杨寺庄下寒武统辛集组单板类13种,腹足类2种,未定类1种。其中包括2新属6新种:Repenoconus xinjiensis gen.nov.,Scenella pycna sp.nov.,Securiconus vulgaris sp.nov.,Obtusocnus grossicostus sp.nov.,Igorellina proboscis sp.nov.,Gal  相似文献   

13.
Abstract:  A new suite of arthropod trace fossils, attributed to a decapod crustacean, is described from the Lower Jurassic Saltford Shale Member of the Blue Lias Formation of Southam Cement Works Quarry, eastern Warwickshire, England. Solusichnium southamensis igen. et isp. nov. consists of small, isolated, bilaterally symmetrical, suboval hypichnia, comprising three regions. The concave anterior region contains imprints of chelate appendages, antennae and antennules. The elongate middle region contains abdominal appendage imprints that extend laterally, separated by a bifurcated medial imprint. The convex posterior region terminates in a globular V-shaped telson imprint. The large sample size and range of trace morphologies allows identification of five morphotypes within a taphoseries. S. southamensis is found on the base of siltstone lenses in what is otherwise a dysaerobic laminated mudstone unit, associated with epichnial Rusophycus , and the suite of trace fossils is interpreted as the resting traces (Cubichnia) and escape reactions (Fugichnia) of small decapods that were trapped below a distal storm deposit. The producer of S. southamensis was possibly an Eryon -like decapod, similar to those known from the slightly older Wilmcote Limestone Member of southwestern Warwickshire.  相似文献   

14.
Summary A unique small bioherm, 0.7 m in diameter and 0.25 m high, is described from the Lower Keuper in South Germany. Its core consists of the attached right valves of the tiny oyster-like lamellibranchPlacunopsis ostracina (Pectinacea). It is overgrown by a cm-thick laminated stromatolitic crust formed by microbial mats and sponges. The bioherm was dolomitized during early diagenesis and represents the temporary transition from restricted marine to more saline depositional environments. It is one of the stratigraphically youngestPlacunopsis bioherms found so far in the Germanic Triassic.  相似文献   

15.
A new bivalved arthropod is described from the Lower Cambrian (?Upper Atdabanian) Buen Formation of North Greenland. Pauloterminus spinodorsalis gen. et sp. nov. possesses a bivalved carapace that covers the head, which has a single pair of antennae, and anteriormost thorax. No mouthparts are visible. The five‐segmented abdomen was limbless and terminated in a telson plus a pair of large, lobate uropods. A suite of at least six biramous thoracic limbs are present: the short endopods are made up of small, serial podomeres, while the exopods are lobate and may have functioned as gills as well as in swimming. Partially infilled guts are occasionally visible, suggesting that this animal may have been a sediment feeder. It is compared to other Cambrian bivalved arthropods, especially the waptiids Chuandianella ovata from the Lower Cambrian Chengjiang fauna (China) and Waptia fieldensis from the Middle Cambrian Burgess Shale (British Columbia). Of these three animals, the Greenland and Chinese taxa appear to be the most closely related. P. spinodorsalis possesses many typical arthropod features, but it also demonstrates more primitive characters that are more reminiscent of the lobopodians.  相似文献   

16.
Nanogomphodon wildi n. gen., n. sp. is based on a tiny lower postcanine tooth from the lower Lettenkeuper (Lower Keuper or Erfurt Formation; Ladinian) of Michelbach an der Bilz (Baden-Württemberg). It represents the first record of a traversodont cynodont from the Middle Triassic of Europe and exhibits a distinctive combination of dental features. Along with recent discoveries of other traversodont taxa from the Upper Triassic of eastern North America,Nanogomphodon indicates the existence of a distinct lineage of these cynodonts in the Northern Hemisphere.   相似文献   

17.
For a long time, the highly aberrant crinoid Scoliocrinus was known only from the Lower Givetian Eifel area (western Rhenish Massif) as a single oblique calyx with only two out of five radials having an arm facet. Several almost complete crowns of a new species in the Middle Givetian Finnentrop area (eastern Rhenish Massif) have two fan-like arms (in the A and E rays), and a horizontal large anal tube. The probable mode of life of Scoliocrinus is analysed by (a) functional morphology mainly of the arms, (b) criteria of minimised faecal recycling, (c) biostratinomic association with two new species of another aberrant, but four-armed new crinoid genus thus suggesting original syntopy with Scoliocrinus. It is concluded that the construction of Scoliocrinus is probably an adaptation to prevailing unidirectional (tidal?) currents in biostromal reef biotopes. This is supported by rather similar crinoid occurrences in a Lower Givetian biostromal reef-related region in the western Rhenish Massif, with the genotype of Scoliocrinus and a newly assigned third species of Scoliocrinus (arm and probable part of the calyx), as well as four-armed species. The new forms are described as Scoliocrinus ubaghsi nov. sp., Scoliocrinus gerolsteinensis nov. sp., Trapezocrinus scheeri nov. gen., nov. sp., and Trapezocrinus hilperti nov. gen., nov. sp.  相似文献   

18.
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   

19.
New caddisflies, reculid and eoblattid insects from the Mesozoic of Asia are described. Caddisflies of the families Philopotamidae (Mesoviatrix paradoxa gen. et sp. nov. and Kempia piotri gen. et sp. nov.) and Polycentropodidae (Polylongevus eskovi gen. et sp. nov.) from the Upper Jurassic–Lower Cretaceous of the Kempendyai locality in Yakutia are described. A short review and comparison of fossil members in these families are provided. New Gryllones insects, Shurabia tanga sp. nov., Sauk batkenicus gen. et sp. nov. from the Sauk Tan’ga locality (Lower Jurassic of Kyrgyzstan), Say kirgizicus gen. et sp. nov. from the Shurab III locality (Reculida: Geinitziidae; Lower or Middle Jurassic of Kyrgyzstan) Griphopteron iya sp. nov. (Eoblattida: Blattogryllidae) from Iya locality (Middle Jurassic of Russia) are described.  相似文献   

20.
Early ontogenetic shells of 25 species of brackish water and freshwater molluscs from the Ottnangian (Lower Miocene) Oncophora Beds (Lower Bavaria, South Germany) and Kirchberg Formation (Upper Bavaria, South Germany) are described for the first time. Taxonomic implications are discussed. The investigated bivalves (Cardiidae and Dreissenidae) were characterised by an indirect development with inclusion of a planktonic veliger stage. Among the gastropods only three species of the genus CtyrokiaSchlickum, 1965 were characterised by veliger larvae, all the other gastropod species were direct developers, which hatched as crawling young. The species Agapilia schlickumi nov. sp. (Neritidae), Nematurella pseudozilchi nov. sp. and Nematurella strauchi nov. sp. (Hydrobiidae) are introduced. Our study revealed the co-occurrence of 10 molluscan species in the Oncophora Basin of Lower Bavaria and the Kirchberg Basin of Upper Bavaria and thus indicates similar oligohaline to mesohaline coastal swamp milieus for both depositional environments. The presence of planktonic larval development in gastropods indicates a connection to the open sea.  相似文献   

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