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1.
Two new genera, Repkinella and Aristotreta, and five new species from the class Lingulata (Brachiopoda) are described from the Upper Cambrian olistolith limestone enclosed in the Upper Ordovician olistostrome from the Agyrek mountains (northeastern Kazakhstan). The family Curticiidae Walcott et Schuchert is referred to the order Lingulida, not order Acrotretida, where it was previously placed. 相似文献
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A new genus and species of a Middle Cambrian stem group brachiopod, Acanthotretella spinosa n. gen. and n. sp., is described from the Burgess Shale Formation. Most of the 42 specimens studied came from the Greater Phyllopod bed (Walcott Quarry) and were collected from five bed assemblages, each representing a single obrution event. Specimens are probably preserved within their original habitat. In contrast to all brachiopods known from the Burgess Shale, the shells of the new stem group brachiopod are often deformed and do not show signs of brittle breakage, which suggests that the valves were originally either entirely organic in composition or, more likely, had just a minor mineral component. Acanthotretella spinosa differs from all the other described Cambrian brachiopods in that it is covered by long, slender and possibly partly mineralized spines that are posteriorly inclined at an oblique angle away from the anterior margin. The spines penetrate the shell and are mainly comparable with the thorn‐like organic objects that have been inferred from early siphonotretoid brachiopods. The pedicle was slender and was composed of a central coelomic region and emerged from an apical foramen at the end of an internal pedicle tube. The finding of a pedicle attached to the macrobenthic algae Dictyophycus and other epibenthos implies that A. spinosa did not have an infaunal mode of life. The visceral region and interior characters are poorly preserved. 相似文献
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Christian B. Skovsted 《Pal?ontologische Zeitschrift》2003,77(2):429-443
Mobergellans are disc-shaped problematic fossils of phosphatic composition bearing prominent muscle attachment structures
on the presumed internal surface. They are found exclusively in sediments of Early Cambrian age, mainly from Laurentia, Baltica
and Siberia. Type material ofDiscinella brastadi Poulsen, 1932 from North-East Greenland is re-studied and synonomised withDiscinella micans (Billings, 1871). Specimens from Siberia described asD. brastadi are re-assigned toMobergella hexactina n. sp., and specimens from Siberia described asMobergella radiolata
Bengtson, 1968 are re-assigned toM. sibirica n. sp.Aktugaia triangula
Mis-Sarzhevsky, 1976 from Kazakhstan is redescribed, and its relationship to other mobergellans is discussed.
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A new conodont species, Antognathus vjatsheslavi sp. nov., is described from the Famennian shallow-water carbonate deposits of the Bolshoi (Greater) Karatau Range in southern Kazakhstan. 相似文献
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《Palaeoworld》2016,25(3):333-355
The Yangtze platform of South China offers evidence within its Ediacaran–Cambrian geological record of the Cambrian explosion and diversification events in metazoan history. To understand the explosive radiation of animals and the environments in which it took place, the basal Cambrian fauna succession of the Aijiahe section in the Three Gorges area, western Hubei Province, has been studied, revealing the earliest brachiopod fauna (Tsunyidiscus trilobite Zone) in this region, which was dominated numerically by acrotretoids. This is accompanied by abundant skeletal fossils including minute well-preserved phosphatized archaeocyath cups and an assortment of abundant sponge spicules, chancelloriids, mollusks, hyoliths, and bradoriids, retrieved by acid-etching limestone interbeds in the black shale-dominated Shuijingtuo Formation (Series 2). The brachiopods comprise two species of acrotretoids, two types of botsfordiids (Botsfordiidae gen. et sp. indet. A and B), and four species of linguloids. Of the latter, Spinobolus popovi n. gen. n. sp. is strikingly distinctive and typified by spine-like ornamentation seen for the first time in the lower Cambrian; the remaining three linguloid genera, Palaeobolus, Eoobolus, and Lingulellotreta, have a trans-paleocontinental distribution. The Three Gorges Shuijingtuo brachiopod assemblage differs from that of the upper Atdabanian Stage (Cambrian Stage 3) in Siberia and South China, but shows great similarities with those discovered in the Tsanglangpuan (equivalent to Botoman or Stage 4) Stage of eastern Yunnan Province, Siberia, and South Australia, suggesting a much more prolonged sedimentary hiatus in basalmost Shuijingtuo Formation of the Three Gorges area than previously expected. The presence of such unconformities provides a caveat to stable isotope-based correlations that involve a number of discussions of global ocean geochemical changes across the time interval that witnessed Cambrian explosion of metazoans. 相似文献
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JIN YUGAN WANG HUAYU 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1992,25(1):35-49
Jin Yugan & Wang Huayu 1992 01 15: Revision of the Lower Cambrian brachiopod Heliomedusa Sun & Hou, 1987. Lethaia , voi. 25. pp. 35–49. Oslo. ISSN 0024–1164.
Fossils referred to Heliomedusa , from the Chiungchussu Formation of Early Cambrian age in Yunnan. are extraordinarily preserved. They were previously considered to represent jellyfish. and have been suspected more recently of being an obolellid brachiopod. A study of the morphology of this genus indicates that it is related closely lo the non-pediculate craniopsids. which occurred from Early Ordovician to Carboniferous time. The soft parts of this brachiopod. such as setae and nerves, which usually are not preserved in fossils also are described. Brachiopoda, Inarticulata, Craniapsidue, anatomy, setae, nervous system, mantle canals, Early Cambrian . 相似文献
Fossils referred to Heliomedusa , from the Chiungchussu Formation of Early Cambrian age in Yunnan. are extraordinarily preserved. They were previously considered to represent jellyfish. and have been suspected more recently of being an obolellid brachiopod. A study of the morphology of this genus indicates that it is related closely lo the non-pediculate craniopsids. which occurred from Early Ordovician to Carboniferous time. The soft parts of this brachiopod. such as setae and nerves, which usually are not preserved in fossils also are described. Brachiopoda, Inarticulata, Craniapsidue, anatomy, setae, nervous system, mantle canals, Early Cambrian . 相似文献
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R. Kh. Kadyrbekov 《Entomological Review》2016,96(4):445-451
Two new species of the genera Uroleucon Mordvilko, 1914 and Pleotrichophorus Börner, 1930 are described from Kazakhstan. Uroleucon dzhungaricum sp. n. feeding on Senecio nemorensis L. (Asteraceae) in the Dzhungar Ala Tau is closely related to U. minor (Börner, 1940). Both these species differ from the closely related U. solidaginis (Fabricius, 1794) in a smaller length ratio between the processus terminalis and the 3rd antennal segment (0.8–1.0 versus 1.0–1.5). The new species differs from U. minor (Born.) in a greater number of the secondary rhinaria on the 3rd antennal segment of the apterous viviparous females (21–37 versus 15–21), in a fewer number of hairs on the cauda (10–16 and 15–23), and in the host plant. Pleotrichophorus ugamicus Kadyrbekov, sp. n. feeding on Artemisia santolinifolia Turcz. is described from the Sairam-Ugam Natural Park (Southern Kazakhstan). The new species is similar to P. glandulosus (Kaltenbach, 1846) and P. achilleae Holman, 1965. Pleotrichophorus ugamicus sp. n. differs from these species in the length ratio of the processus terminalis to the base of the 6th antennal segment (4.1–5.0 versus 5.0–9.0 and 5.1–6.2), in that of the ultimate rostral segment to the 2nd segment of the hind tarsus (0.68–0.76 versus 0.80–0.97 and 0.80–0.90), and in the host plant. This species differs from P. glandulosus in the ratio of the length of dorsal hairs on tergites I–V to the basal diameter of the 3rd antennal segment (1.0–1.2 and 1.4–1.7). In addition, the new species differs from P. achilleae in the length ratio of the 3rd antennal segment to the 6th segment (0.56–0.66 versus 0.70–0.87) and to the processus terminalis (0.67-0.82 versus 1.39–1.80), as well as in the shape of the dorsal hairs. A key to the Palaearctic species of the genus Pleotrichophorus is presented. 相似文献
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A Ceriodaphnia has been found inWaterbodies of the plains and foothills of Uzbekistan and southern Kazakhstan that strongly resembles C. reticulata (Jurine, 1820). The female of this new species, C. turkestanica, differs from C. reticulata because it lacks a fenestra (nucal organ) in the cervical notch of the adult, has a rostral pore encircled by a ridge of cuticle rather than opening on the flat surface of a polygon anterior to the antennules, and has fewer and finer spines punctuating the row of fine spinules along the inner margin of the posterior carapace. The locule of the ephippium lacks the regular, small, rounded protuberances seen in the locule of C. reticulata. The male of C. turkestanica also exhibits the lack of a cervical fenestra, an encircled rostral pore, and variable, fine spines along the posterior carapace inner margin. In addition, it has a much shorter terminal seta on the antennule, and increasing lengths of the spinose setae on endites 1–3 of trunk limb I rather than the second being the longest as in C. reticulata. Because of similarities between these species, we suggest that C. turkestanica either is derived from C. reticulata or that the two share a common ancestor. 相似文献
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The white-flowered Tulipa kolbintsevii (Liliaceae), section Biflores, occurs in SE Kazakhstan, Dzjungarian Ala-Tau, Taskora valley. So far only T. aff. altaica and T. brachystemon (sect. Kolpakowskianae) both with yellow flowers, flushed greenish–violet or red on the outside, were known to be present there. It differs in that it is not only the easternmost species of the section Biflores, and has different placement of hairs on the tepals, but also has the lowest genome size of the species in this section with 2C?=?48?pg. The other 14 species have 51.5–59.4?pg. Flow cytometry supported morphological differences. This method is useful for identification of dormant bulbs or sterile plants and is therefore important for monitoring of the trade in bulbous species. 相似文献
14.
J. B. Waterhouse 《Pal?ontologische Zeitschrift》1982,56(1-2):39-52
Five new genera and species are described from brown silty mudstone near Huai Bun Nak, north-east Thailand. New taxa areProrugaria thailandica n. gen., n. sp. (Family Rugosochonetidae);Tuberculatella tubertella n.gen., n.sp. (Family Overtoniidae);Minispina alata n.gen., n.sp. (Family Marginiferidae);Aspinosella sinauris n.gen., n.sp. (Family Retariidae) andMucrospiriferinella undulosa n.gen., n.sp. (Family Xestotrematidae). The age is considered to be younger Carboniferous. 相似文献
15.
Helicoplacoid echinoderms occur in Lower Cambrian shales and mudstones along the northern coast of Laurentia, now western North America. The group originally contained four genera and nine species, diagnosed by differing ambulacra, plate length-to-width ratios, and plate ornament. Ambulacra are identical in all specimens except for the single example of Waucobella nelsoni, and the remaining morphologic differences are caused by ontogeny. The characters used to diagnose seven of the original nine species are therefore invalid, reducing the group to three genera and three species. These are: Helicoplacus gilberti Durham and Caster, 1963, Waucobella nelsoni Durham, 1967, and Polyplacus kilmeri Durham, 1967, which has a test composed of ambulacra, and likely represents a developmental oddity. 相似文献
16.
Maria Aleksandra Bitner 《ZooKeys》2015,(537):33-50
Twenty species belonging to 16 genera, i.e. Neoancistrocrania, Novocrania, Basiliola, Basiliolella, Ebiscothyris, Stenosarina, Kanakythyris, Xenobrochus, Terebratulina, Eucalathis, Fallax, Frenulina, Septicollarina, Campages, Annuloplatidia, and Thecidellina have been identified in the material collected during the Terrasses and Exbodi cruises in the New Caledonian region, SW Pacific. The species Basiliolella
grayi (Woodward, 1855) and Fallax
neocaledonensis Laurin, 1997 are the most common in the studied collection, while Eucalathis
murrayi (Davidson, 1878) is reported for the first time from the New Caledonian region. 相似文献
17.
Kathleen Burt-Utley 《Brittonia》1982,34(2):189-198
Begonia buseyi, B. croatii, B. dressleri andB. morii from Panama andB. louis-williamsii from Guatemala are described as new, illustrated and discussed. 相似文献
18.
《Palaeoworld》2015,24(4):438-444
A variety of echinoderm ossicles have been discovered in the middle to upper Cambrian rocks of the North China Craton. Material was collected from two localities: Shuangqiao (SQ) section (Paibian) in Hebei Province and Linyi (LY) (Guzhangian?–Paibian?) in Shandong Province. Six types of ossicles can be recognized, including rounded thecal plates, and columnals with a narrow lumen and ridged articulating facets. The combination of characters suggests an unknown stalked echinoderm, probably an eocrinoid, with relatively advanced columnal morphology. 相似文献
19.
A new subfamily, Pseudobrieniinae, including the new genus Pseudobrienia and the new species Pseudobrienia rasnitsyni, Kararhynchus jurassicus, and K. gratshevi, are described from the Middle-Late Jurassic of Karatau. K. occiduus Zherikhin et Gratshev, 1993 is redescribed. 相似文献
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HOWARD R. FELDMAN 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1980,13(1):27-46
Depositional environments of the Onondaga Limestone from central to southeastern New York are found to be normal, subtidal marine, due to the absence of characteristic supratidal or intertidal sedimentary features and the presence of a typical, diverse, marine level-bottom community framework. Post-mortem transport has not been extensive, as evidenced by low articulation ratios, lack of abraded valves, and complete ontogenetic gradations within species, which precludes large scale winnowing. Sedimentation rates appear to have been greatest in eastern New York where the Onondaga Limestone reaches a thickness almost three times that of the strata in central New York. Shaly beds in the central area represent periods of cessation of carbonate deposition rather than an influx of clastic material. Deposition terminated with the onset of deeper water characterized by a westerly advance of terrigenous sedimentation (the Marceilus Shale of the Hamilton Group). Nine brachiopod communities can be recognized in the Onondaga Limestone. There is a strong correlation between sediment-substrate and community type, reflecting the sedimentologic control of brachiopod community distribution. Sandy facies, cherty limestones and coral biostromes and bioherms are associated with inner-neritic deposition in Edgecliff time; argillaceous lime muds and lime sands are characteristic of mid-neritic deposition in Nedrow to Moorehouse time; and highly argillaceous lime muds are associated with outer-nerittc deposition in Seneca time. 相似文献
