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The style of embryonic development in the lingulids has changed through time; that of Recent lingulids is not primitive for the group. The shell of Devonian lingulids consists of two valves already at the embryonic stage, whereas in Recent lingulids the protegulum originates as a single plate, subsequently folded in two. The protegulum of the Devonian lingulids is a cup-shaped, subcircular plate, usually with a characteristic radial sculpture suggesting the presence of marginal setae, similar to those occurrilg in early juvenile stages of Recent discinids. Devonian protegula are 81 to 100 µm in width and thus are three times smaller than protegula of the Recent Lingula utd Glottidia, and twice as small as those of the Late Cretaceous Lingula sp. The embryonic development of lingulids underwent important modification during last 370 Ma.
A new record of the phosphate microbrachiopod genus Acrotretella Ireland, 1961 from the Lower Ordovician of the Baltic syneclise, in north-east Poland is the oldest known species of the genus. Acrotretella goldapiensis sp. n. co-occurs with conodonts in shallow-water facies of Late Llanvirn age. The new data from Poland extend the statigraphical range of the genus from the Llanvirn to the middle Silurian (Ludlow); during the later Ordovician and Early Silurian Acrotretella apparently migrated westwards to sequentially occupy shallow-water facies on the palaeocontinents of Baltoscandia (Poland and Sweden), Avalonia (England), Laurentia (North America) and Australasia (Australia) with relatively little morphological change.
An abundant early Silurian brachiopod assemblage of 14 species, with strong affinities to the early Rhuddanian faunas of Britain and Baltoscandia, was recovered from the Akkerme Peninsula, on the western side of Lake Balkhash, southern Central Kazakstan. The occurrence of Stricklandia lens mullochensis, which is ttre earliest member of the Stricklandia-Costistricklandia lineage, dates this brachiopod assemblage as early Rhuddanian, within a stratigraphic interval from the Akidograptus acuminatus to the lower part of the Monagraptus cyphus graptolite biozones. This is the first well documented record of early Rhuddanian brachiopods in Kazakhstan. The assemblage also includes Meifodia tulkulensis sp. nov. and Eospirifer cinghizicus with well preserved spiralia. The co-occurrence of Stricklandia lens mullochensis and Eospirifer cinghizicus has not been recorded previously and is regarded here as the most signiffcant difference between the early Rhuddanan brachiopod faunas of the Baltic (East-European) Plate and Britain; in contrast Eospirifer first appears in the two latter areas in the late Llandovery.
Brachiopod faunas from the Devonian stromatoporoid-coral series (Kowala Formation) of the southern Holy Cross Mts comprise at least 60 species, atrypids and ambocoeliid spiriferids being the most common. Largely monospecific bottom-level pioneer assemblages colonized intershoal and open shelf environments of the Late Givetian Sitkówka bank complex to the Frasnian Dyminy reef complex, and some lagoonal habitats of the older Givetian Stringocephalus bank. The associations dwelling organic buildups were more diverse and specialized. Faunal dynamics of the brachiopods were controlled primarily by eustatic cycles and the evolution of the carbonate shelf. Generally this was a four-step succession from the stringocephalid to the ambocoeliid, atrypid (or cyrtospiriferid), and rhynchonellid faunas. Twenty two species are reviewed,Praewaagenoconcha(?) sobolevi sp. n., Desquamatia globosa aequiconvexa subsp. n., and D. g. sitkowkensis ssp. n. are proposed. Two poorly-known species of Gürich (1896), Tenticospirifer lagoviensis and Ilmenia(?) elatior, are redescribed.
A new atrypid Waiotrypa sulcicarina gen. et sp. n. from the late Frasnian of the Holy Cross Mountains is proposed. The new genus is close to Iowatrypa Copper, 1973 from which it differs mainly in having a keeled pedicle valve and sulcate brachial valve. Waiotrypa is one of the latest atrypids prior to extinction of the order at the end of the Frasnian.
The paper presents the detailed quantitative study of predatory scars in the shells of an inarticulate brachiopod: the lingulid Glottidia palmeri Dall, 1870. The scars include four morphological types: u-shaped, pocket, crack, and miscellaneous scars. They concentrate and open up toward the anterior shell edge. They commonly consist of a pair of scars on the opposite valves. The analysis of 820 specimens live-collected from two intertidal localities in the northern Gulf of California indicates that (1) 23.4% specimens bear repair scars; (2) the scars vary in size from 1.5 to 24 mm² (mean = 2.5 mm²) and all scar types have similar size-frequency distributions; (3) the spatial distribution of scars on the shell is non-random; (4) the anterior-posterior distribution of scars is strongly multimodal and suggests seasonal predation in the late fall and winter months; and (5) the frequency of scarred specimens increases with brachiopod size and differs between the two sampled localities, but does not vary among brachiopod patches from the same locality. The repair scars record unsuccessful attacks by epifaunal intertidal predators with a scissors-type weapon (birds or crabs). The high frequency of attacks, seasonal winter predation, and previous ecological research suggest that scars were made by wintering shorebirds (willets or/and curlews). However, crabs cannot be entirely excluded as a possible predator. Because repair scars represent unsuccessful predation, many of the quantitative interpretations are ambiguous. Nevertheless, the study suggests the existence of strong seasonal interactions between inarticulate brachiopods and their predators. Because shorebirds, crabs, and lingulids may have co-existed in intertidal ecosystems since the late Mesozoic, predatory scars in lingulid shells may have potentially a 100 million year long fossil record.
A new species of the poorly known lingulate brachiopod Schizobolus is described from the Famennian (Upper Devonian) of Poland. S. polonicus sp. n. has a triangular pedicle notch and a small listrium, indicating that it belongs to the Trematidae within the superfamily Discinoidea. S. polonicus retains some linguloid features, such as a linguloid-like 'pedicle groove' and a V-shaped imprint of the pedicle nerve. The disturbance band, which occurs in the apical part of the larval shell, probably delimits two stages of growth, namely pre-larval (embryonic?) and larval, or, early-larval and late-larval. S. polonicus is the youngest member of the genus, and of the family Trematidae. Five incompletely preserved discinids from the Famennian of Łagów are described as Trematidae gen. et sp. indet.
A sample taken from a detrital limestone lens, presumed to be allochthonous, within the dark coloured argillaceous limestone of the Early Carboniferous Muhua Formation at the Muhua section, Guizhou, South China, yielded numerous, mostly silicified fossils. Ostracodes, which are the most numerous in the sample, were studied by Olempska (1999). Brachiopods and conodonts are described and illustrated in this paper, but other associated fossils are also noted. Among brachiopods the most common are productides, orthotetidines, spiriferides, and orthides. The productoid gen. et sp. indet. 2, Lambdarina sp., and rhynchonelloid gen. et sp. indet. most probably represent new taxa, but are described in open nomenclature because of inadequate material. Conodonts are indicative of late Tournaisian age. The fossil assemblage is represented by phosphatic and silicified remnants, the latter being originally calcitic. The pattern of silicification resulted generally in preservation of skeletal morphology in great details.
A shell of the Famennian spiriferoid brachiopod Cyrtiorina sp., from the Dębnik anticline in southern Poland, displays a severe damage, probably the result of a bite by a jawed or clawed predator. The injury comprises several indentations on the pedicle valve and partial disarticulation of the shell exposing large areas of soft tissue in living animal. The brachiopod successfully repaired the damage, demonstrating its ability to recover from sublethal injuries. It is suggested that the attacker may have been repelled of the brachiopod’s soft tissues, as has been observed in some Recent articulates.
Five types of brachiopod-bivalve assemblages occur in Terebratula Beds and in the lower part of the Karchowice Beds (Middle Triassic, Muschelkalk) from the Strzelce Opolskie Quarry (Upper Silesia). These are: (1) Brachiopod coquina Assemblage dominated by the terebratulid brachiopod Coenothyris vulgaris; (2) Crumpled/Wavy Limestone Assemblage including bivalves and brachiopods; (3) Bivalve Coquina Assemblage dominated by pseudocorbulid bivalves; (4) Hardground Assemblage dominated by the brachiopod Tetractinella trigonella; and (5) Crinoid Limestone Assemblage dominated by crinoid columnals and the brachiopod Punctospirella fragilis. The distribution of the assemblages correlates with the eustatically-controlled lithological variation in the carbonate- dominated sequence of the Upper Silesian Muschelkalk. The brachiopod coquinas are parautochtonous remnants of terebratulid banks which thrived during the high bioproductivity but low oxygen conditions. Those conditions were caused by the biogenic influx generated from the terrains flooded during the Middle Triassic transgression. During the regressive phase, that resulted in the gradual decrease in bioproductivity and parallel increase in oxygen levels, the terebratulid banks were replaced by pseudocorbulid banks. With the further regression - and thus, the further increase in oxygen level - pseudocorbulid banks were replaced by the assemblages indicative of well-oxygenated oligotrophic environments (Hardground and Crinoid Limestone Assemblages). The observed changes in the faunal composition reflect mainly differences in metabolism and feeding strategy among dominant taxa.
Givetian and Frasnian stromatoporoid-coral limestone of the Kowala Formation in the southern Holy Cross Mts is subdivided stratigraphically, and correlated with strata elsewhere on the basis of identified sea-level cyclicity, with support from conodonts and other selected benthic fossils. After the Eifelian hypersaline sabkha phase, an extensive two-step regional colonization of the Kielce Region carbonate platform took place during the Eifelian/Givetian passage interval and the Middle Givetian. At least four deepening pulses resulted in intermittent drowning of the vast carbonate platform and sequential replacement of the undifferentiated Stringocephalus biostromal bank by the Sitkówka bank complex and, subsequently, by the Dyminy reef complex. The reef developed in the central Dyminy belt as result of the early Frasnian accelerated sea-level rise after some period of biotic stagnation near the Givetian-Frasnian boundary. Final demise of the reef resulted from combined eustatic and tectonic movements during the late Frasnian major crisis interval.
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