Famennian Brachiopod Research Articles

Upper Devonian brachiopods from the core of the Kurgan-Uspenskaya-1 key borehole (south-western outlying areas of Western Siberia)

Research subject. Brachiopods from the core of the Kurgan-Uspenskaya-1 parametric borehole. The borehole was drilled in the south of Western Siberia 80 km southeast of the Kurgan town. Brachiopods were collected at a depth of 1,525.4 m in the IV tectonic block (core interval 1,450–1,794 m) in the greenish-gray marls of the Famennian stage of the Upper Devonian.Materials and methods. The paleontological material is presented in the form of complete undamaged shells and individual valves of small- and medium-sized brachiopods. The safety of brachiopods makes it possible to determine their species and genera, sometimes in open nomenclature. The article provides a brief description of the available material.Results. 11 species of brachiopods of the subtype Rhynchonelliformea belonging to six orders and nine genera were identified. The following ten species were described: Orbinaria fallax (Pand.), Semiproductus amplus Bubl., Schuchertella sp., Dalejina? sp., Camarotoechia panderi (Sem.et Moell.), C. volucera Nal., Athyris tobolica Nal., Cleiothyridina tenuilineata (Row.), Cl. ex gr. pectinata (Sem. et Moell.), Retzia? sp. The presented information allows conclusions about the age of the sediments enclosing the brachiopods under study and expands the existing knowledge of both the composition of the Upper Famennian brachiopods of the basement of the south of Western Siberia and their geographical and stratigraphic distribution.Conclusion. An analysis of the stratigraphic distribution of the described brachiopods taking into account data on foraminifera allowed us to determine the age of the host rocks as the very top of the Famennian stage. The composition of the brachiopods allows these rocks to be correlated with coeval deposits of the East European Platform, Timan, the Urals, Kuzbass, the Gorny Altai, Kazakhstan and North America.

Biological Diversity, Crisis and Recovery in the Phong Son Formation (D<sub>3</sub>-C<sub>1</sub> <i>Ps</i>), Thua Thien-Hue Province, North-Central Vietnam

The present of Upper Devonian and Lower Carboniferous sediments and fossils in Hue City, Van Xa area, Huong Thuy District; Thanh Tan, Hien An villages, Dong Lam Quarry, Phong Dien District, Thua Thien-Hue Province has been noted in recent years depend on explosion of limestone underlying the Quaternary cover for cement technology and building. The Phong Son Formation has been established with two members: the underlying Van Xa Member composed of mainly limestone, 280 m thick, containing abundant Famennian brachiopods, crinoids, gastropods; the overlying Hien An Member composed of limestone intercalated with black shale, 210 m thick, containing abundant brachiopods, crinoids, bryozoans, stromatoporoids, corals, trilobites, foraminiferans, gastropods of Latest Famennian-Tournaisian age. Over 1000 macrofossil examples were collected from both the Van Xa Member and Hien An one for analyzing biological diversity, crisis and recovery of all macrofossil group of stratigraphical level of the Phong Son Formation (D₃-C₁ <i>ps</i>). In the Famennian stage, the diversity is related to representatives of phyla Brachiopoda, Cnidaria, Mollusca; belonging to the <i>Cyrtospirifer</i>-<i>Yunnanella</i> Assemblage. In the Tournaisian stage, the recovery and diversity is related to reprensentatives of phyla Porifera, Cnidaria, Arthropoda, Brachiopoda, Bryozoa, Mollusca, and Echinodermata; belonging to the <i>Leptagonia-Phillipsia </i>Assemblage. The crisis at the DCB of the Phong Son Fm is well displayed in phyla Brachiopoda, Cnidaria and Porifera.

Patterns of cornulitid encrustation on the Late Devonian brachiopod shells from Russia

Upper Devonian brachiopods from the Central Devonian Field, Russia have been investigated with respect to encrustation patterns of cornulitids. These Palaeozoic encrusters were very characteristic component of shelly substrates during the Devonian and may serve as valuable objects for palaeoecological studies, especially those concerning the encrusters-host relationships. On the basis of rich material, it has been shown that cornulitid abundance significantly increased in the lower Famennian. Their disparity also increased from one morphotype (robust) present in the upper Frasnian to two distinct morphotypes (robust and slender, presumably representing two different species) in the lower Famennian. The analysis of the spatial occurrence of cornulitids on two dominant lower Famennian brachiopod species (Cyrtospirifer zadonicus and Ripidiorhynchus huotinus) showed, that these encrusters preferred the marginal parts of the shells. This, together with a dominant directional growth of cornulitids toward the commissure, indicates that cornulitids benefited from food brought by feeding currents produced by the brachiopod’s lophophore. The unequivocal evidence for syn vivo association of the cornulitids and their brachiopod hosts is the presence of distinct shell malformations caused by cornulitid growth affecting the host’s shell-secreting epithelium, preserved on some lower Famennian specimens. Interestingly, these malformations were caused by a slender cornulitid morphotype only. Thus, it is evident that during food gathering from the inhalant currents, this cornulitid species exerted a distinct, negative effect on the brachiopod – a deviation of its shell growth. In this case, we may consider this particular cornulitid species as ectoparasite rather than commensal with respect to its host.

Upper and uppermost Famennian (Devonian) brachiopods from north-western France (Avesnois) and southern Belgium

1. Introduction As noted by several authors (e.g. Gosselet, 1857; Cooper, 1954; Conil et al., 1986; Simakov, 1990; Mottequin et al., 2014), radiations were recorded among several brachiopod orders during the uppermost Famennian (Upper Devonian). Numerous productide, spiriferide, spiriferinide and rhynchonellide genera first appeared during this interval and are characterized by morphological features heralding the Mississippian brachiopod faunas. Brice et al. (2013) recently stressed that the brachiopod data related to the uppermost Famennian of the Avesnois (north-western France) (Fig. 1), which is the historical type area of the Strunian (Streel et al., 2006), strongly need to be updated in order to detail the consequences of the Hangenberg Crisis (Kaiser et al., 2011, 2015). In this area, the last comprehensive study on uppermost Famennian brachiopods dates back to Dehée (1929). His study, based on Gosselet, Delépine, Carpentier and Dehée’s material, is poorly stratigraphically constrained and some elements of the fauna described by Dehée (1929), such as the atrypides, were not obtained from the uppermost Famennian (Copper, 1986). The brachiopods were subsequently and partly revised by Vandercammen (1956), Legrand-Blain (1991), Brice (1997), Nicollin (2004, 2008) and Brice et al. (2013). The situation is more critical in southern Belgium where the mixed carbonate-siliciclastic Strunian facies are relatively similar to those occurring in the Avesnois. In Belgium, the vast

Encrustation patterns on post-extinction early Famennian (Late Devonian) brachiopods from Russia

A study of patterns of episkeletobiont encrustation on the shells of two early Famennian brachiopods, Cyrtospirifer zadonicus and Ripidiorhynchus huotinus from Russia, revealed assemblages comprising seven skeletonised encruster taxa. The assemblages are dominated by spirorbiform microconchids, followed by cornulitids. Features such as shell malformations, frequent encruster growth towards the commissure of the shells, and encruster distribution in the areas adjacent to zones of possible water intake by the brachiopods indicate that these may have been colonised syn vivo. The lack of differences in encruster abundance between the two valves in C. zadonicus indicates that this species may have lived with both valves inclined at a high angle to the substrate. The significantly higher abundance of episkeletobionts on the brachial valves of R. huotinus may indicate that shells of this species were oriented with the brachial valve at a lower angle to the substrate, providing sheltered sites for coelobiotic larvae. Compared with pre-Famennian brachiopod-hosted encruster communities, this early Famennian community is impoverished in species richness and is dominated by microconchids. It is proposed that the epibionts witnessed a regression-related Frasnian–Famennian extinction event. During the recovery interval, opportunistic microconchids may have been among the first encrusters to colonise the pioneering brachiopods.

Middle and Late Devonian brachiopod assemblages, sea level change and paleogeography of Hunan, China

Givetian through middle Famennian brachiopods of Hunan are used to define five biozones, comprising, in ascending order, the Stringocephalus Abundance Zone, the Ambocoeliid-Leiorhynchid Assemblage Zone, the Cyrtospiriferid Assemblage Zone, the Yunnanellina-Sinospirifer Assemblage Zone, and the Yunnanella-Hunanospirifer Assemblage Zone. They correspond approximately to the Po. hemiansatus Zone to Po. varcus Zone, S. hermanni Zone to Pa. punctata Zone, Pa. hassi Zone to Pa. linguiformis Zone, Pa. triangularis Zone to Upper Pa. crepida Zone, and Uppermost Pa. crepida Zone to Pa. marginifera Zone, respectively. Intensified rifting activity in South China during the Devonian began in the middle of the Lower Po. varcus Zone (a level marked by the first appearance of Po. rhenanus), which is consistent with the Lower-Middle Givetian substage boundary suggested by the International Subcommission on Devonian Stratigraphy (SDS). This assumed that rifting activity in the Lower Po. varcus Zone was signified by the deposition of the Baqi Formation in Guangxi and was marked largely by the extensive deposition of the Qiziqiao Formation in central Hunan, which probably led to an opposite pattern of relative sea level change-rising in deeper water trough areas and lowering in carbonate platform areas. The previously recognized S. hermanni Zone sea level rise in platform margin areas of Guangxi can be identified not only in the trough areas but also in platform areas, which probably indicates an overall marine transgression at this time, rather than tectonically induced sea level change. Similarly, this level coincides with the Middle-Upper Givetian substage boundary suggested by the SDS. Although the sea level rise may have occurred in the deeper water trough areas of South China towards the end of the Givetian, platformal areas experienced uplifting at various degrees, especially in the central and northern regions of Hunan where Early Frasnian deposits were apparently absent in many places. Similarly, the end-Frasnian regression led to exposure of many places and absence of early Famennian deposits, which probably accounts for the restricted distribution of the Yunnanellina brachiopod fauna.

Latest Famennian Brachiopods from Kowala, Holy Cross Mountains, Poland

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 Fa...

Famennian brachiopod and gastropod occurrences on top of Devonian seamounts, Elbingerode and Iberg Reefs, Harz Mts., Germany

Famennian brachiopods and gastropods occur locally on top of the Elbingerode and Iberg Reefs (Harz Mts.). The Elbingerode occurrence is found in a small depression of the former reef surface and belongs to thePalmatolepis triangularis conodont-zone. It is a brachiopod-gastropod packstone, which also contains limited numbers of crinoids, solitary corals, and trilobites. The Iberg occurrence is a crinoid grainstone, which contains few brachiopods and solitary corals. The grainstone is found in two neptunian dikes cutting the reef, and belongs to thePalmatolepis marginifera conodont-zone. Five brachiopod and five gastropod taxa are described, with the new speciesHolopea ruchholzi. Stable isotopes (δ13C, δ18O) of cement and matrix of Famennian limestones suggest no relation to a methane seep, as described for the different, late Visean brachiopod limestone on top of the Iberg Reef.

Biostratigraphical value of some Strunian (Devonian, uppermost Famennian) Productidina, Rhynchonellida, Spiriferida, Spiriferinida brachiopods

The space of Devonian time considered in this paper corresponds to the uppermost part of the Famennian or the latest Famennian as a fourfold subdivision of the stage, usually called by many authors Strunian in neritic facies and Wocklumeria Stufe or Wocklumian in pelagic facies. Here, we examine the biostratigraphical value of certain brachiopod genera and species as bio-markers of the uppermost Famennian throughout the world (Europe, the former USSR, Middle East, Asia, North America, North Africa, and Australia). We have focused our study for species which stratigraphical range has been firmly established in correlation with the conodont biozones (Upper expansa, Early, Middle and Late praesulcata), the ammonoid biozones (do VI = “ Wocklumeria Stufe”), or the foraminifera biozones ( kobeitusana Zone). Other data for which the stratigraphical range is not based on standard biozonation are provided in the annex. The brachiopod bio-markers discussed in this paper belong to 14 Productidina genera ( Acanthatia, Araksalosia, Ericiata, Hamlingella, Mesoplica, Nigerinoplica, Orbinaria, Ovatia, Rugauris, Semiproductus, Sentosia, Spinocarinifera, Steinhagella, Whidbornella), 7 Rhynchonellida genera ( Araratella, Centrorhynchus, Hadyrhyncha, Megalopterorhynchus, Novaplatirostrum, Rozmanaria, Tchanakhtchirostrum), 13 Spiriferida genera ( Brachythyris, Cyrtospirifer, Dichospirifer, Eochoristites, Imbrexia, Parallelora, Prospira, Rigauxia, Sphenospira, Tenisia, Toryniferella, Tylothyris, Voiseyella) and one Spiriferinida genus ( Syringothyris). Other orders have not been studied in this paper. The main features of the uppermost Famennian brachiopod taxa represented in this paper are commented. All these taxa are listed as completely as possible throughout the world (with complements in the annex). A quick summary of the geographic distribution of the more represented taxa is given in conclusion.

Late Devonian (Frasnian) brachiopods from the Wadleigh Limestone, Southeastern Alaska

A brachiopod fauna from the upper part of the Wadleigh Limestone, Alexander terrane, southeastern Alaska, is of late Frasnian age and includes the new taxa Gypidula cornuta alaskensis n. subsp., Gypidula upatensis n. sp., Gypidula perryi n. sp., Gypiduloides craigensis n. gen. and sp., Parapugnax schmidti n. sp., Westbroekina chaconenesis n. gen. and sp., Emanuella altus n. sp., Emanuella neumani n. sp., Adolfispirifer sanjuanensis n. sp., Theodossia albertoensis n. sp., Cyrtospirifer paridaensis n. sp., and Tenticospirifer wadleighensis n. sp. A few other taxa are cosmopolitan or conspecific with species known from elsewhere in western North America. The fauna overall may have North American affinities but includes an unusual number of previously undescribed forms. This lends support to the view, based on the affinities of Frasnian conodonts from this same locality (Savage, 1992) and Famennian brachiopods described from nearby (Savage et al., 1978), that these Alexander terrane faunas were not in general communication with Late Devonian North American cratonic faunas to the east.

The Famennian brachiopod Zilimia polonica (Gürich) and its palaeoenvironmental significance

The rhynchonellid brachiopod Zilimia polonica (Gürich, 1896) is described, based on new topotypic material. The neotype of the species comes from the lower Famennian Upper crepida zone. The crinoidal marls containing Z. polonica and an associated brachiopod assemblage are regarded as cohesive debris flow material, redeposited from shallow-water into an adjacent intrashelf basin. The distribution of Z. polonica suggests that it populated open-marine, moderately shallow environments within the swell and basin topography developed along the margins of the East European and the eastern cratons.