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1.
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A skeleton of a ghost pipefish (Solenostomidae) from the Pshekha Subformation of the Khadum Formation (Lower Oligocene) in the Republic of Adygea was discovered. This is the first fossil record of Solenostomidae in Russia; moreover, it is the only ghost pipefish found in the Oligocene. To date, only two fossil solenostomid genera and species from the Eocene of Monte Bolca (Italy) have been recorded. The only Recent genus of this family, Solenostomus Lacepède, 1903, contains four species. The new specimen is incompletely preserved; it lacks a fragment of the body and some fins, precluding the establishment of genus and species of this form. However, the unique geographical position and age of the new fossil expand our knowledge of the evolution and geographical range of the family Solenostomidae.  相似文献   

3.
A new specimen of the family Satyridae from Céreste is described. The specimen is an isolated right forewing. It is classified as a satyr because of the swelling at the base of some veins and of the presence of a postdiscal eye-spot. The color patterns as well as the dimensions of the wing characterize the fossil as a member of the speciesLethe? corbieri (Nel et al. 1993).Together with other fossil butterflies this specimen demonstrates the importance of the satyres in the Oligocène of Southern France. Among modern butterflies only the families of the Satyridae and the Hesperiidae are highly specialized on grasses as host plants for their caterpillars. Besides some satyrs true skippers are also known from the Oligocène of Southern France. The frequency of fossils of these two families probably indicates a Lower Oligocene spreading of grasses in Europe.  相似文献   

4.
Krings M  Taylor TN  Dotzler N 《Mycologia》2011,103(3):455-457
Evidence of fossil Peronosporomycetes has been slow to accumulate. In this review various fossils historically assigmed to the Peronosporomycets are dicussed briefly and an explanation is provided as to why the fossil record of this grouop has remained inconsistent. In recent year there has been several new reports of fossil peronosporomycetes based on structurally preserved oogonium-antheridium complexes from Derovonian and Carboniferous rocks that demonstrate the existence of these organisms as fossils and refute the long-standing assumption that they are too delicate to be preserved. Among these are serral tyoes characterized by oogonial surface members of the group. To date at last three groups of fossil vascular plants (i.e. lycophytes, ferns and seed ferns) are known to host peronosporomycetes aas endophytes; however only one form has been identified as a parasite.  相似文献   

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《Geobios》1986,19(5):647-652
A second fossil lamprey is described from the Lower Carboniferous (Namurian) locality of Bear Gulch (Montana, U.S.A.), which had already yielded the type specimen of Hardistiella montanensis, the oldest and, probably, the most primitive of all known lampreys. This new specimen, which may possibly belong to the latter species, is badly preserved, but clearly shows the impressions of four to six branchial pouches which are relatively small and closely set, like those of the other Carboniferous lamprey Mayomyzon pieckoensis. They differ thus from extant lampreys, in which the branchial apparatus extends relatively far behing the eyeballs. This concentration of the branchial apparatus in early lampreys is regarded here as a primitive condition, which is also met with in many anaspids, as evidenced from their closely-set external branchial openings. The presence of an impression which recalls the loop of the trabecles in larval extant lampreys suggests that this specimen was a larval individual.  相似文献   

7.

Background

The best European locality for complete Eocene mammal skeletons is Grube Messel, near Darmstadt, Germany. Although the site was surrounded by a para-tropical rain forest in the Eocene, primates are remarkably rare there, and only eight fragmentary specimens were known until now. Messel has now yielded a full primate skeleton. The specimen has an unusual history: it was privately collected and sold in two parts, with only the lesser part previously known. The second part, which has just come to light, shows the skeleton to be the most complete primate known in the fossil record.

Methodology/Principal Findings

We describe the morphology and investigate the paleobiology of the skeleton. The specimen is described as Darwinius masillae n.gen. n.sp. belonging to the Cercamoniinae. Because the skeleton is lightly crushed and bones cannot be handled individually, imaging studies are of particular importance. Skull radiography shows a host of teeth developing within the juvenile face. Investigation of growth and proportion suggest that the individual was a weaned and independent-feeding female that died in her first year of life, and might have attained a body weight of 650–900 g had she lived to adulthood. She was an agile, nail-bearing, generalized arboreal quadruped living above the floor of the Messel rain forest.

Conclusions/Significance

Darwinius masillae represents the most complete fossil primate ever found, including both skeleton, soft body outline and contents of the digestive tract. Study of all these features allows a fairly complete reconstruction of life history, locomotion, and diet. Any future study of Eocene-Oligocene primates should benefit from information preserved in the Darwinius holotype. Of particular importance to phylogenetic studies, the absence of a toilet claw and a toothcomb demonstrates that Darwinius masillae is not simply a fossil lemur, but part of a larger group of primates, Adapoidea, representative of the early haplorhine diversification.  相似文献   

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Abstract: A specimen of Curculionidae (Curculioninae) is described as Arariperhinus monnei gen. et sp. nov. The specimen is preserved on a laminated limestone sample of the Crato Formation (Santana Group), Lower Cretaceous (Aptian–Albian), and was collected from a quarry near Nova Olinda, Chapada do Araripe, State of Ceará, Brazil. The genus is placed in the subfamily Curculioninae because of its strongly convex body and relatively slender rostrum, but mainly by its rounded eyes and lack of a prosternal sulcus and tibial spurs. The very prominent eyes in lateral view, a cylindrical rostrum and a straight posterior margin of ventrite II are strong indications that this fossil belongs to the tribe Anthonomini. However, the claws, which would resolve the exact placement of this fossil, are poorly preserved. Arariperhinus monnei gen. et sp. nov. is distinguishable by the combination of several characters and the first record of the family Curculionidae in the Santana Group; it is the oldest record of a member of the subfamily Curculioninae.  相似文献   

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《Geobios》1988,21(4):409-433
Cattybrook Claypit, on the northwest margin ofthe Bristol-Somerset Coalfield, yields an upper Westphalian A (Middle Carboniferous) fossil flora. Most of the fossils are of small plant fragments, transported mainly by winds into floodbasin muds. They represent a variety of plant-types, including pteridosperms, ferns, cordaites, sphenophytes and lycophytes. Of particular interest are finely preserved examples of Lonchopteris, and Corynepteris, which are generally scarce in British floras of this age. Also found at Cattybrook are plant fragments in a crevasse-channel sandstone. These are preserved nearer their original position of growth, and are thus more complete than those found in the floodbasin deposits. They include almost complete fronds of Karinopteris attached to a thick lianatype stem, and large pieces of a Sphenophyllum plant. This is now the best documented late Westphalian A flora in Britain.  相似文献   

13.
A fossil trimerous flower from the Turonian (ca. 90 MYBP, Upper Cretaceous) of New Jersey is described as a new genus in the familyLauraceae. The fossil flower is charcoalified and preserved in exceptional detail. This fossil specimen is particularly remarkable in that several pollen grains have been preserved; pollen grains ofLauraceae generally have very thin exine and are rarely preserved in the fossil record. Although the specimen is incomplete and lacks anthers, there are sufficient structural details preserved to permit an assignment to theLauraceae, as well as comparisons with the tribePerseeae. This new genus provides an important addition to our knowledge of systematic and structural diversity in CretaceousLauraceae.  相似文献   

14.
The higher rank systematics of coleoid cephalopods are primarily based on the total number of arms. Completely preserved arm crows are, therefore, the most important character complex by which fossil representatives can be assigned to higher taxa. Whereas belemnoids—similar to modern Decabrachia—are well-known to have ten hooklet-bearing arms, recent studies have shown that Middle-Late Jurassic and Late Cretaceous gladius-bearing coleoids belong to the Vamyropoda, owing to having only eight hooklet-free arms. The arm number of Early Jurassic gladius-bearing coleoids was unclear for a long time. This paper, however, reports the first unequivocally complete arm crown from the Early Jurassic (Toarcian). It consists of eight strongly phosphatised arms of equal shape. Affinity with decabrachiate coleoids is therefore unlikely. The mantle sack of the specimen, which was identified as Loligosepia aalensis (Schübler in Zieten, 1832), has, furthermore, an unusual arrangement of numerous angular pieces. The irregular scattering of the mantle fragments was most probably caused by a scavenger. Finally, hooklets in the food residues in the posterior mantle indicate that Loligosepia preyed upon belemnites.  相似文献   

15.
Middle Jurassic fossil plants from the Grisethorpe Bed at Cayton Bay and Grisethorpe Bay, Yorkshire, UK, are preserved in a soft claystone, and plant mesofossils recovered by sieving reveal excellent details of external structure. Studies of these mesofossils complement previous work on macrofossils from the Grisethorpe Bed and allow the plant fossils in this classic flora to be studied in a similar way to those preserved in Cretaceous mesofloras. Bennettitales, a key group in discussions of how angiosperms may be related to other seed plants, are especially well represented among mesofossils from the Grisethorpe Bed. Abundant bennettitalean leaves, scale leaves, and fragments of pollen and ovulate organs provide new information on these extinct plants. In particular, a specimen of Williamsoniella coronata (presumed aborted) shows only weak differentiation between interseminal scales and ovules and provides further evidence of homology between these structures.  相似文献   

16.
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   

17.
The early history of Panorpidae (Mecoptera) is poorly known due to sparse fossil records. Up to date, only nine fossil species have been described, all from the Paleogene, except the Early Cretaceous Solusipanorpa gibbidorsa Lin, 1980. However, we suggest S. gibbidorsa is too incompletely preserved to permit even family classification. A new genus with two new species, Jurassipanorpa impunctata gen. et sp. n. and Jurassipanorpa sticta sp. n., are described based on four well-preserved specimens from the late Middle Jurassic Jiulongshan Formation of Daohugou, Inner Mongolia, China. These two new species are the earliest fossil records of Panorpidae. The new genus is erected based on a combination of forewing characters: both R1 and Rs1 with two branches, 1A reaching posterior margin of wing distad of the forking of Rs from R1, and no crossveins or only one crossvein between veins of 1A and 2A. In all four specimens, long and robust setae ranging from 0.09 to 0.38 mm in length and pointing anteriorly, are present on anal veins of forewings. The function of these setae is enigmatic.  相似文献   

18.
Hornworts (Anthocerotophyta) are a main lineage of land plants but they are exceedingly rare as fossils. The only fossil hornwort described from amber has been interpreted as the best preserved fossil of this group. Reinvestigation of this fossil revealed that this Miocene amber inclusion represents a poorly preserved flower that shows some features of the Caesalpinioideae subfamily of the Fabaceae.  相似文献   

19.

Background and Aims

Ericales are a major group of extant asterid angiosperms that are well represented in the Late Cretaceous fossil record, mainly by flowers, fruits and seeds. Exceptionally well preserved fossil flowers, here described as Glandulocalyx upatoiensis gen. & sp. nov., from the Santonian of Georgia, USA, yield new detailed evidence of floral structure in one of these early members of Ericales and provide a secure basis for comparison with extant taxa.

Methods

The floral structure of several fossil specimens was studied by scanning electron microscopy (SEM), light microscopy of microtome thin sections and synchrotron-radiation X-ray tomographic microscopy (SRXTM). For direct comparisons with flowers of extant Ericales, selected floral features of Actinidiaceae and Clethraceae were studied with SEM.

Key Results

Flowers of G. upatoiensis have five sepals with quincuncial aestivation, five free petals with quincuncial aestivation, 20–28 stamens arranged in a single series, extrorse anther orientation in the bud, ventral anther attachment and a tricarpellate, syncarpous ovary with three free styles and numerous small ovules on axile, protruding-diffuse and pendant placentae. The calyx is characterized by a conspicuous indumentum of large, densely arranged, multicellular and possibly glandular trichomes.

Conclusions

Comparison with extant taxa provides clear evidence for a relationship with core Ericales comprised of the extant families Actinidiaceae, Roridulaceae, Sarraceniaceae, Clethraceae, Cyrillaceae and Ericaceae. Within this group, the most marked similarities are with extant Actinidiaceae and, to a lesser degree, with Clethraceae. More detailed analyses of the relationships of Glandulocalyx and other Ericales from the Late Cretaceous will require an improved understanding of the morphological features that diagnose particular extant groups defined on the basis of molecular data.  相似文献   

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