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Retained colour pattern on the shells of Plectodonta sp. from the earliest Devonian of Podolia (Ukraine) is the first finding for strophomenide brachiopods and the oldest among articulate brachiopods. The colour pattern in Plectodonta sp. is composed of small, round, brownish spots scattered rather irregularly on the ventral valve only. This may suggest that the described pattern probably performed a protective function through disruptive camouflage against visual systems of potential predators. The occurrence of the colour pattern in Plectodonta sp. exclusively on the ventral valve strongly suggests that these brachiopods lived with the patterned (and convex) ventral valve upwards and the patternless concave dorsal valve facing to the underlying substrate. It thus contradicts a general assumption that concavo−convex brachiopods lived with their convex valves resting on the sediment.
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Shell morphology and structure in Lingulipora Girty

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The Devonian Lingulipora Girty is the only genus among the Recent and fossil Lingulidae with a punctate shell; its shell structure, however, has been very poorly known. Micro-ornamentation and internal structure of the shell as well as the structure of its endopuncta are here studied on specimens isolated chemically from various horizons of the Upper Devonian. The material includes specimens with strong radial ornamentation in the form of sharp ridges as well as specimens with strong concentric ornamentation. The internal structure of both the valves was examined. The endopuncta are in the form of simple cylindrical canals 4 to 15 µm in diameter, distally covered by canopy 1.5 to 2.6 µm thick. Canopy is perforated by one opening, usually 1 to 2 µm in diameter but sporadically wider. The hypothetical function of caeca in Lingulipora is discussed in comparison to those in living and fossil Brachiopoda.
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A double-spired brachiopod Biernatella polonica gen. et sp.n. is described for the first time from the Upper Devonian of Southern Poland. A new family Biernatellidae has been established for it within the Dayioidea.
The results of investigations on Stringocephalus burtini from the Limestone of Dziewki, Givetian, vicinity of Siewierz, with some remarks on the palaeoecology of the species are given.
The described assemblage of brachiopods from the Givetian of Jurkowice-Budy (= Stringocephalus burtini Beds), Holy Cross Mountains comprises 6 species including one newly erected Crurithyris jurkowicensis n.sp. Some observations on the ontogeny and morphology of Ilmenia hians, Rensselandia gibbosa and Stringocephalus burtini based on numerous young specimens are made. The paleoecology of the whole assemblage is discussed and the periodic disappearance of the benthonic fauna is judged to be due mainly to the oscillatory changes in the sea salinity.
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.
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Devonian athyridoid brachiopods with double spiralia

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A double-spired athyridoid, morphologically transitional between Early Devonian Helenathyris and Late Devonian Biernatella has been identified in the Givetian of the Holy Cross Mts., Poland. It appears that in the course of evolution between these brachiopods dental plates and cardinal plate atrophied. The biernatellids may have developed a diplospiralium independently of Triassic diplospirellids. They originated either from the Siluro-Devonian lineage represented by Coelospira, Anoplotheca, Bifida and Kayseria or, more likely, they can be derived from their pre-Devonian common ancestors. Biernatellids were probably well adapted to environments with a poor supply of food. Eobiernatella rackii gen. et sp. n., Biernatella ovalis sp. n., and B. lentiformis sp. n. are proposed.
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.
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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.
In the classic section across the Silurian–Devonian boundary at Dnistrove (Podolia, Ukraine) the brachiopod fauna has never been studied in detail. This paper presents results of research on brachiopods from this important locality and time interval. Bed−by−bed collecting has enabled the detailed distribution of brachiopod taxa through the boundary beds to be revealed. Generally, the reference section at Dnistrove yields rather scarce but often well preserved brachiopods. Dayia bohemica and Dnestrina gutta can be regarded as characteristic species for the uppermost Silurian. A relatively high−diversity but low−abundance brachiopod fauna occurs in the lowest 1.8 m of the earliest Devonian. Only three forms have been found to cross the Silurian–Devonian boundary: the strophomenide Plectodonta (Plectodonta) mariae pantherae subsp. nov., the atrypide Gracianella (Sublepida) paulula sp. nov., and the spiriferide Howellella (Howellella) latisinuata. A relatively narrow brachiopod−rich interval at 5.5 m above the Silurian–Devonian boundary yields 16 brachiopod species which probably indicate a setting near the lower limit of the photic zone equivalent to the Benthic Assemblage 3–4 boundary. Two new species and one new subspecies are described: Skenidioides tatyanae, Plectodonta (Plectodonta) mariae pantherae, and Gracianella (Sublepida) paulula.
The brachiopod faunas from deposits recording the Early–Middle Frasnian transition of Poland are poorly known. The present report describes these faunas that were recovered from Wietrznia and Kostomłoty (Holy Cross Mountains) and Dębnik (Silesian−Cracow Upland) regions positioned on the southern Polish carbonate shelf. The brachiopod distribution was analysed relative to a significant δ¹³C excursion, referred recently to as Palmatolepis punctata Event. The sporadic occurrence of brachiopods at Dębnik makes it difficult to analyse the biotic response to this geochemical anomaly. However, higher brachiopod frequency in the topmost part of the section coincides with a gradual decrease of δ¹³C down to the Frasnian background values. At two studied sections at Wietrznia the greatest taxonomic diversity and abundance of brachiopods (Flabellulirostrum–Coeloterorhynchus assemblage) are confined to the Palmatolepis transitans Zone. In the following Pa. punctata Zone brachiopods are rare (Biernatella lentiformis assemblage) or absent, which suggests a serious deterioration of the environmental conditions linked probably with periods of benthic anoxia−dysoxia and oligotrophic conditions in the basin. In two Kostomłoty sections brachiopods faunas of this age are members of the mostly monospecific rhynchonellid−dominated Phlogoiderhynchus polonicus assemblage which inhabited deeper−water environments characteristic of intrashelf oxygen−depleted basins of ŁysogóryKostomłoty region. In some horizons large shells of P. polonicus were frequently colonised by discinoid Romerella? sp. Among 28 species described in this report new forms include: Flabellulirostrum kielcensis sp. nov., F. rackii sp. nov., and Thomasaria ventosa sp. nov.
Four specimens of Coeloterorhynchus schucherti (Stainbrook, 1945) from the Frasnian of southern Poland retain their color pattern of the shell preserved in form of several radial stripes.
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.
The new trench Z−17 situated in the Dębnik anticline (Cracow Region, southern Poland) exposed strata representing the Frasnian–Famennian boundary interval. The latest Frasnian crisis interval is characterized by the fauna of Ryocarhynchus tumidus interval consisting of the nominal species, Barroisella campbelli, Biernatella polonica, and representives of Lingulipora, Athyris, ?Retichonetes, Longispina, Cyrtospirifer and Warrenella. The first brachiopods that appears immediately above the F–F boundary in the survival interval include the unidentified rhipidomellid, Praewaagenoconcha cf. speciosa, and Pampoecilorhynchus geniculatus sp. nov. The fauna in the succeeding layer is dominated by P. geniculatus and Cyrtospirifer minor. The earliest Famennian repopulation assemblage consists of representatives of Barroisella, ?Rhyssochonetes, Praewaagenoconcha, Nigerinoplica, Schizophoria, unidentified rhipidomellid, Pampoecilorhynchus geniculatus sp. nov., Chapinella striata sp. nov., Crinisarina angelicoides, and Cyrtospirifer minor. Low diversity and low frequency brachiopod assemblages consisting of stunted specimens characterize the succeeding brachiopod intervals spanning the remainder of the Palmatolepis triangularis Zone. Basinal dysoxia prevailed in the region for the duration of Pa. triangularis Zone. Resumption of aerobic bottom−water conditions is marked by the appearance of brachiopods of the Dmitria gibbosa interval (Pa. crepida Zone). Resumption of favorable environmental conditions during the recovery interval is marked by an increase in brachiopod diversity recording the beginning of a strong post−extinction rediversification of the fauna.
The findings of preserved soft body parts including pedicle in the linguloid brachiopods are extremely rare in the fossil record of which the early Cambrian Chengjiang (southern China) and Burgess Shale (British Columbia) faunas are the most important. However, these characteristic Cambrian soft−bodied faunas largely disappeared from the fossil re− cord well before the end of the Cambrian. Here we describe the first record of the pedicle in a linguloid brachiopod from the post−Cambrian strata, preserved with remarkable fidel− ity. Contrary to the Chengjiang and Burgess Shale−type fau− nas which are commonly preserved as essentially two−di− mensional aluminosilicate or degraded organic carbon films or pyritized compressed fossils, the specimens now recov− ered from the Ordovician of China show a three−dimen− sional, pyritized pedicle with preserved external morphol− ogy, in detail. The presence of streamlined shell shape and burrowing shell sculpture in our specimens supports an as− sumption for infaunal mode of life of the genus. Since all linguloid brachiopods of the early Cambrian are inter− preted as epifaunal or semi−infaunal, it seems that the here described Ordovician linguloid is the oldest representative of fully infaunal brachiopods. Apparently, the long vermi− form and flexible linguloid pedicle has appeared as a func− tionally optimized construction.
Latest Famennian (UD−VI, “Strunian”) brachiopod fauna from Kowala (Kielce Region, Holy Cross Mountains, Poland) consists of eighteen species within 6 orders, eleven of them reported in open nomenclature. Characteristic taxa include: Schellwienella pauli, Aulacella interlineata, Sphenospira julii, Novaplatirostrum sauerlandense, Hadyrhyncha sp., Cleiothyridina struniensis. New morphological details of Schellwienella pauli, Sphenospira julii, and Aulacella interlineata are provided. The described latest Famennian brachiopod fauna is distinctly richer than that from underlying upper Famennian deposits (11 species within 4 orders). Majority of species from Kowala seem to have been adapted to deep water settings and/or poor nutrient availability. The stratigraphic separation between Planovatirostrum in the UD−III to UD−V and Novaplatirostrum in the UD−VI observed in Sauerland and in Thuringia is valid also in the Holy Cross Mountains. This is the first comprehensive report of a relatively diversified latest Famennian brachiopod fauna from surface outcrops of Poland.
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.
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