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1.
The morphology of eggs and sperm of echinoderms, mollusks, and brachiopods was studied and compared. The gametes of inarticulate brachiopods (two classes Lingulata and Craniata and two subphyla Linguliformea and Craniaformea) are shown to have significant morphological differences from those of articulate brachiopods (extant class Rhynchonellata, subphylum Rhynchonelliformea). Inarticulate brachiopods have similar sperm morphology to that of primitive brachiopods, bivalves and some polychaetes that have external fertilization. Sperm morphology of articulate brachiopods is similar to that of echinoderms, which are considered to be typical deuterostomate invertebrates. This similarity supports an early deviation of lophophore-bearing animals from Bilateria, before this lineage branched into Protostomia and Deuterostomia. Similar gamete morphology in Lingulata and Craniata supports the view that inarticulate brachiopods should be retained as a supraclass taxon for comparison with other Lophotrochozoa, in particular with phoronids, bryozoans, and mollusks. Based on the new data on the gamete morphology in inarticulate brachiopods, we propose the name Lingulophyles with the type genus Lingula, and for articulate brachiopods Coptothyrophyles with the type genus Coptothyris. 相似文献
2.
A. V. Pakhnevich 《Paleontological Journal》2009,43(11):1458-1468
Mass samples of the micromorphic recent (Hemithyris psittacea, Eucalathis murrayi, Macandrevia cranium, Megathyris detruncate, Argyrotheca cuneata, Argyrotheca cordata) and fossil Silurian (Microsphaeridiorhynchus sp.) brachiopods were studied. New location of Eucalathis murrayi on the Kitovyi Ridge in the Atlantic Ocean is described. Rates of growth of shells were revealed by the study of the sizes
and age of brachiopods. Reasons of dwarfism in brachiopods are discussed. Three strategies of growth of the micromorphic brachiopods
are distinguished. Appearance of micromorphic brachiopods is connected with the changes in the rates of shell growth and life
expectancy. 相似文献
3.
G. A. Afanasjeva 《Paleontological Journal》2008,42(8):792-802
Three controversial problems of brachiopod supraordinal classification are discussed: the position of brachiopods in the classification
of Metazoa, their classification at phylum and class level, and the classification of the articulate brachiopods. The position
of brachiopods in the system of Metazoa remains uncertain. There are no strong reasons for changing the traditional division
of the phylum Brachiopoda into the classes Inarticulata and Articulata. The class Articulata is divided into the subclasses
Orthata, Strophomenata, Spiriferata, and Terebratulata. 相似文献
4.
RICHARD H. MILLER FREDERICK A. SUNDBERG 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1984,17(3):185-190
Specimens of inarticulate brachiopods (family Acrotrctidae) with boreholes were found in Upper Cambrian carbonates in the southern Great Basin of the United States. Some morphologic features and preferred orientation of the borings are similar to those made by predators and previously reported in the fossil and Holocene record. Such predatory activity on brachiopods is previously unknown in Cambrian rocks. Taxa associated with these specimens are not known to have been predators and identity of the predatory organism is unknown. Cambrian brachiopods, predation, paleoecology. 相似文献
5.
Alberto Prez-Huerta Nathan D. Sheldon 《Palaeogeography, Palaeoclimatology, Palaeoecology》2006,230(3-4):264-279
As with modern organisms, the spatial and temporal distribution of fossil communities was controlled by both the physical setting in which the organisms lived and by the organisms' physiology and interactions. By studying the sedimentological and geochemical context of fossil communities, it is possible to assess the relative importance of the physical setting and the organisms' physiology. Comparison of Pennsylvanian brachiopod associations with changing sedimentological context (water depth/facies) and nutrient availability indicates that body size is a function of water depth and nutrient availability for most spire-bearing (athyridids and spiriferids) brachiopods but rarely for productid brachiopods. Spire-bearing brachiopods dominate the associations in high-nutrient settings, and productid brachiopods dominate the associations in low-nutrient settings. This difference suggests that physiological differences between brachiopod orders, such as lophophore filtering efficiency, play an important role in controlling their distribution. 相似文献
6.
The fossil record of drill holes in marine invertebrates has received a considerable amount of interest from paleontologists, primarily due to its importance for reconstructing the history of interactions between drilling predators and their prey. Such drill holes have been described in numerous studies of Paleozoic brachiopods but rarely in those focusing on brachiopods of the post-Paleozoic, a striking pattern given that in the late Mesozoic and Cainozoic drilling gastropods diversified and frequencies of drilled molluscs increased dramatically. During the past several years, however, drilled brachiopods were reported in several studies of the Mesozoic and Cainozoic, suggesting that this phenomenon may be more common than has been previously assumed. Here we report on 10 genera of brachiopods from four Cainozoic basins in Australia of which 7 shows evidence of having been drilled by predators. Of 298 specimens examined, 38 contain a single complete hole. Drilled specimens were identified in all 4 basins and in all stratigraphic units. When considered in the context of recent reports of drilled Cainozoic brachiopods, these Australian brachiopods further imply that drilling predation on these invertebrates was geographically, taxonomically and temporally widespread. 相似文献
7.
O. N. Zezina 《Paleontological Journal》2008,42(8):830-858
The vertical, latitudinal, and circumcontinental zonality of the distribution of the species, genera, and families of recent
brachiopods is considered. The distortions of the latitudinal and meridional symmetry of the biogeographic structure of the
ocean are analyzed in view of the patterns of the global circulation of the surface and intermediate waters. Thus ancient
faunas may be reconstructed based on data on the structural characteristics of the taxocene of recent brachiopods. The features
of the paedomorphic evolution of brachiopods from the different families in extreme habitats (interstitial, underwater caverns,
submarine rises, abyssal depths, hydrothermal areas, and margins of habitats) are discussed. The biogeographic structure of
bottom dwellers is shown to simplify with depth as well as with simplification of the hydrological structure of the ocean.
The important role of the bathyal oceanic zone (slopes of continents, islands, submarine mountains, ridges, and rises) in
the preservation of faunal relicts is shown. The historical change from brachiopods to bivalves that occurred from the Paleozoic
to the Mesozoic and Cenozoic is shown to have resulted not from competitive exclusion, but from complex and global changes
in the plankton composition, which were unfavorable for articulate brachiopods, which had already developed specialized feeding
habits, feeding on food that led to the production of almost no metabolic waste products; they had even partly lost their
alimentary canal. The development of shelly plankton and, especially, of diatoms hampered the post-Paleozoic revival of large
assemblages of articulate brachiopods in shallow-water habitats. The unfilled ecological niches were colonized by bivalves,
which were widely adapted to feeding on live phyto-and zooplankton. Recent articulate brachiopods, which are adapted to feeding
on the products of decay of dead plankton, form a belt of densely populated settlements of the organic biofilter outside the
photic zone on the seaward edge of shelves and on the upper parts of the slopes of continents, islands, and submarine rises
throughout the world. 相似文献
8.
The monophyletic origin of the Brachiopoda 总被引:1,自引:0,他引:1
ALBERT J. ROWELL 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1982,15(4):299-307
Although it is commonly acepted that the brachiopods descended from phoronid-like ancestors there is dispute over their origin. Traditionally they have been regarded as a monophyletic group, a clade. More recently it has been claimed that brachiopods are polyphyletic and that several of the orders arose independently from separate phoronid-like stocks. The latter point of view implies that brachiopods are not a taxon but merely a grade of organization. Traditional stratophenetic approaches do little to resolve the problem, which may be outside their domain. It is possible, even probable, that the initial radiation involved organisms that lacked mineralized shells. Cladistic analysis of both living forms and Lower Paleozoic taxa strongly supports the contention that brachiopods are monophytetic and closely related to the phoronids. It suggests, however, that the 'inarticulate' Paterinida and Kutorginida are genealogically more closely related to the Articulata than they are to the remaining Inarticulata. □ Brachiopoda, Lophophorata, cladistics, Cambrian. 相似文献
9.
G. A. Afanas’eva 《Biology Bulletin》2012,39(2):137-151
In this work we discuss the results of ontogenetic and morphobiological approaches to phylogenetic reconstructions of articulate
brachiopods on the basis of morphogenetic data. These data provide the basis for generalizations concerning phylogeny and
system of orders. The ontogenetic approach was the subject of criticism mainly because of arbitrary establishment of the homology
of brachiopods. The constraints of the morphobiological approach are associated with the phenomena of morphological evolution
without adaptive explanation so far. As an example of these phenomena, homeomorphism of brachiopods can be considered. Prospects
for morphogenetic studies of brachiopods can be connected with the study of characteristic elements of their shell structure,
such as porosity and mantle channels. 相似文献
10.
SPAFFORD C. ACKERLY 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1992,25(3):243-247
Ackerly, S. C. 1992 07 15: The origin and geometry of radial ribbing patterns in articulate brachiopods.
Geometric models for simple. radial ribbing in articulate brachiopods include (1) ribs radiating isometrically from the shell umbo. (2) divergence of thc ribs from some 'point' within the shell, and (3) reorientation of the ribs at right angles to the shell margin. Analyses of the Orthida, the ancestral taxon of articulate brachiopods, indicate that rib geometries are isometric in Early Cambrian taxa (model 1). but that by the Early Ordovician rib orientations are generally perpendicular to the shell margin (model 3). A combination of functional and morphogenetic Factors explains the ribbing geometries observed in orthide brachiopods. 相似文献
Geometric models for simple. radial ribbing in articulate brachiopods include (1) ribs radiating isometrically from the shell umbo. (2) divergence of thc ribs from some 'point' within the shell, and (3) reorientation of the ribs at right angles to the shell margin. Analyses of the Orthida, the ancestral taxon of articulate brachiopods, indicate that rib geometries are isometric in Early Cambrian taxa (model 1). but that by the Early Ordovician rib orientations are generally perpendicular to the shell margin (model 3). A combination of functional and morphogenetic Factors explains the ribbing geometries observed in orthide brachiopods. 相似文献
11.
Ya. E. Malakhovskaya 《Paleontological Journal》2008,42(5):479-490
Shell structure in members of the genus Kutorgina, Lower Cambrian brachiopods with calcareous shells and primitive articulation, is described for the first time. This type of shell structure resembles that of the Lower Cambrian mollusks and hyoliths rather than of brachiopods. 相似文献
12.
G. T. Ushatinskaya 《Paleontological Journal》2008,42(8):776-791
Brachiopods first appeared at the very beginning of the Phanerozoic together with the first skeletal organisms. Most brachiopod
taxa that arose in the first half of the Cambrian had a short temporal range and became completely extinct by the middle of
the Middle Cambrian. Rigid articulation of the valves of brachiopods was provided by various structures, which also appeared
in the Early Cambrian. This fact points to the importance of this feature for the formation of the whole group and at the
same time testifies to the high variability of rigid articulation at the early stages of brachiopod evolution. This is a typical
manifestation of archaic diversity in this animal phylum, which appeared very early in the Phanerozoic. Another important
property of the archaic diversity of the early brachiopods was the large number of centers of diversification. As for the
majority of groups, climatic zonality was the main factor determining the distribution of brachiopods at the beginning of
the Phanerozoic. The main ecological types of brachiopods also appeared in the Early Cambrian. 相似文献
13.
14.
Zhifei Zhang Jian Han Yang Wang Christian C. Emig Degan Shu 《Proceedings. Biological sciences / The Royal Society》2010,277(1679):175-181
The classic Chengjiang Lagerstätte (Lower Cambrian, Atdabanian stage: Yu''anshan Formation) Yunnan, southwestern China, has yielded, besides the exceptional and often controversial soft-bodied fossils, a fauna of primitive/early lingulid brachiopods. Diandongia pista (Rong 1974) is one of the commonest and most strongly mineralized of the phosphatic brachiopods from the Lagerstätte. The shells of this species have been found to commonly serve as a basibiont host. Epibionts comprise the coeval brachiopod Longtancunella chengjiangensis and the cone-shaped cnidarian-related Archotuba conoidalis, as well as rounded smaller-sized epizoans (lesser than 2 mm). A principle morphological analysis demonstrates that the ovoid and rounded organisms that often occur along the commissure of D. pista resemble small juvenile or immature brachiopods. Epibiont-bearing shells of D. pista with soft-tissue preservation demonstrate that the host brachiopods were overgrown while alive, and provide an argument for D. pista having a semi-infaunal life style with only the slim pedicle embedded in sediment. The epibiotic association sheds direct light on the ecology of Cambrian brachiopods in soft-substrate marine environments. The Chengjiang fossils demonstrate that the Early Cambrian brachiopods, as compared with recent lingulids, occupied different and a wider spectrum of ecological niches and tiers of space. 相似文献
15.
A. A. Madison 《Paleontological Journal》2009,43(11):1469-1476
Shell structure of the first-formed shell of the Middle Ordovician orthid-like brachiopods from the Leningrad Region is described.
The 190-μm-wide first-formed shell is composed of finely granular layer while 700-μm-wide first-formed shell is fibrous. Thus
the order Orthida in the Early Paleozoic included brachiopods with both planktotrophic and lecithotrophic larvae in the ontogeny. 相似文献
16.
MAJKEN K. SCHIMMEL MICHAŁ KOWALEWSKI BRIAN P. COFFEY 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(2):274-289
Schimmel, M., Kowalewski, M. & Coffey, BP. 2011: Traces of predation/parasitism recorded in Eocene brachiopods from the Castle Hayne Limestone, North Carolina, USA. Lethaia, Vol. 45, pp. 274–289. The Castle Hayne Limestone (Middle Eocene, North Carolina), noted for its diverse macro‐invertebrate fossils, was sampled to assess if Early Cenozoic brachiopods from eastern North America record any traces of biotic interactions. Systematic surveys of two North Carolina quarries yielded 494 brachiopods dominated by one species: Plicatoria wilmingtonensis (Lyell and Sowerby, 1845). Despite subtle variations in taphonomy, taxonomy and drilling patterns, the two sampled quarries are remarkably similar in terms of quantitative and qualitative palaeoecological and taphonomic patterns. In both quarries, brachiopods contain frequent drillholes (24.5% specimens drilled). The majority of drillholes were singular, perpendicular to shell surface and drilled from the outside. Ventral valves were drilled slightly more frequently than dorsal ones, but site‐selectivity in drilhole location was not evident. Larger brachiopods were drilled significantly more frequently than smaller ones. However, drillhole diameter did not correlate with brachiopod size. The drillholes are interpreted as records of ‘live‐live’ biotic interactions, representing either predatory attacks or parasitic infestations or a combination of those two types of interactions. A notable fraction of specimens bear multiple drillholes, which is consistent with either parasitic nature of interactions or frequent failed predatory events. The high drilling frequency reported here reinforces other reports (from other continents and other epochs of the Cenozoic), which suggest that brachiopods may be an important prey or host of drilling organisms in some settings. The number of case studies reporting high frequencies of drilling in brachiopods is still limited and thus insufficient to draw reliable generalizations regarding the causes and consequences of these occasionally intense ecological interactions. □Brachiopods, drilling parasitism, drilling predation, Eocene, North Carolina, taphonomy. 相似文献
17.
JOSEPH H. MAKURATH 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1977,10(3):235-256
Sedimentological analysis of the Keyser Limestone (Upper Silurian - Lower Devonian of the central Appalachians) indicates that its sediments were deposited in a range of marginal and shallow marine environments. Major depositional environments include: tidal flat, lagoon, barrier bar and island, and open marine shelf. Each major environment is represented by a lithofacies which is lithologically and faunally distinct. Tidal flat lithofacies are characterized by eurytopic organisms, including ostracodes, gastropods, stromatoporoids and blue-green algae. Lagoon lithofacies are dominated by bryozoans, brachiopods, ostracodes and stromatoporoids. Barrier lithofacies are characterized by rooted crinoids, encrusting bryozoans and robust brachiopods. Open shelf lithofacies contain a diverse fauna of cystoids, crinoids, bryozoans and brachiopods.
The distributions of faunal assemblages in the Keyser show no simple relationship to either water depth or distance from shore. They are, in general, related to the distributions of depositional environments.
Recurring associations of brachiopod genera were not found in the Keyser. With few exceptions, any genus may be found in any subtidal environment. Abundance of brachiopods is related to the abundance of local hard substrates (usually bryozoans). 相似文献
The distributions of faunal assemblages in the Keyser show no simple relationship to either water depth or distance from shore. They are, in general, related to the distributions of depositional environments.
Recurring associations of brachiopod genera were not found in the Keyser. With few exceptions, any genus may be found in any subtidal environment. Abundance of brachiopods is related to the abundance of local hard substrates (usually bryozoans). 相似文献
18.
JAN BERGSTRÖM 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1968,1(3):230-237
Finds of brachiopod assemblages in graptolitic shales give support to Ruedemann's theory of an epiplanktic life of certain Palaeozoic brachiopods. The possibly epiplanktic brachiopods observed in the present study belong to the families Obolidae ('Obolus') and Sowerbyellidae (Sericoidea). Other assemblages might have been benthic, and a representative of Chonetidae (Shagamella) is thought to yield an example of this kind of biocoenosis. 相似文献
19.
While it is well established that the shapes and sizes of shells are strongly phylogenetically controlled, little is known about the phylogenetic constraints on shell thickness. Yet, shell thickness is likely to be sensitive to environmental fluctuations and has the potential to illuminate environmental perturbations through deep time. Here we systematically quantify the thickness of the anterior brachiopod shell which protects the filtration chamber and is thus considered functionally homologous across higher taxa of brachiopods. Our data come from 66 genera and 10 different orders and shows well-defined upper and lower boundaries of anterior shell thickness. For Ordovician and Silurian brachiopods we find significant order-level differences and a trend of increasing shell thickness with water depth. Modern (Cenozoic) brachiopods, by comparison, fall into the lower half of observed shell thicknesses. Among Ordovician–Silurian brachiopods, older stocks commonly have thicker shells, and thick-shelled taxa contributed more prominently to the Great Ordovician Biodiversification but suffered more severely during the Late Ordovician Mass Extinction. Our data highlight a significant reduction in maximum and minimum shell thickness following the Late Ordovician mass extinction. This points towards stronger selection pressure for energy-efficient shell secretion during times of crisis. 相似文献
20.
Alexis Rojas Roger W. Portell Michał Kowalewski 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2017,50(2):296-305
Research on drilling predation, one of the most studied biological interactions in the fossil record, has been concentrated on prey with calcareous skeletons (e.g. molluscs, echinoids, rhynchonelliform brachiopods). Based on a compilation of literature sources and surveys of paleontological collections of the Florida Museum of Natural History and the National Museum of Natural History, we provide a tentative evaluation of the post‐Palaeozoic history of drilling predation on the organophosphatic brachiopods of the family Lingulidae. Despite temporal, geographical and methodological limitations of the data assembled here, the results indicate that lingulide brachiopods have been subject to drilling predation since at least the Eocene. Variation in drilling frequencies at the locality level suggests that lingulides may occasionally experience somewhat elevated predation pressures from drilling organisms. Overall, however, drilling predation on lingulide brachiopods has been infrequent in the Cenozoic and may have been absent in the Mesozoic. The Mesozoic‐to‐Cenozoic increase in drilling frequencies on lingulides is similar to the trends observed in other marine benthic invertebrates and consistent with the hypothesis that predation pressures increased through time in marine ecosystems. 相似文献