An Upper Devonian Limestone Slide Block near Marbella (Betic Cordillera, Southern Spain) and the Palaeogeographic Relations between Malaguides and Menorca

Allochthonous Devonian limestone slide blocks are common in the Visléan to probably basal Namurian Retamares Member (lower Almogia Formation) of the Malaguides. The only slide block known from the coastal Palaeozoic between Fuengirola and Estepona is described from the Arroyo de la Cruz W of Marbella. This block is approximately 50 m in diameter and 11 m thick. Four stages of interna1 deformation prove its allochthonous nature. Deformation features and tectonic setting indicate a S to SE derivation. The block is of late Frasnian to early Famennian age. In terms of conodont zonation, it represents the Upper gigas Zone and the Middle Palmatolepis triangularis to Lower rhomboidea Zones, with the Uppermost gigas and Lower Pa. triangularis Zones missing. Pelagic mudstones predominate in rocks of the Upper gigas Zone, whereas fine-grained limestone turbidites, derived from lower slope environments or from intrabasinal rises, piredominate above the hiatus. Carbonate microfacies as well as conodont biofacies point to a deep-water deposition of all limestones. Concurrence of microfacies and biostratigraphy between the slide block and limestones pebbles from conglomerates of the Retamarerj Member prove a common source area. Microfacies and biostratigraphy of carbonate components known from Upper Devonian and post-lower- most Namurian conglomerates of Menorca show striking similarities to those of the Malaguides. Therefore, both limestone blocks and pebbles of the two realms are interpreted to have been reworked from different sectors of a single primary sedimentary basin. This interpretation points to closer palaeogeographic relations between the Malaguides and Menorca

Mississippian (Early Carboniferous) sequence stratigraphy of the Rhenish Kulm Basin, Germany

The Rhenish Kulm Basin is a deeper-water foreland basin developing in front of the Variscan Orogen in Germany. Three major facies interfinger and might overwhelm the adjacent one in time. These are (1) internal siliciclastic flysch facies, (2) central starved basin facies, and (3) calciturbidite facies. Calciturbidites are derived from the Northwest European shallow-water carbonate platform or not preserved intrabasinal sources. Besides, a deep intrabasinal swell facies is characterized by condensed successions. Diagnostic rock types within each facies enable the recognition of systems tracts of third-order depositional sequences. The interpretation of faunal developments and bioevents support these attributions. Hence, for the first time a sequence stratigraphic subdivision of the Rhenish Kulm Basin into 13 sequences is achieved, ranging from the latest Devonian to the early Namurian. The lower nine sequences are correlated with the Dinantian sequences earlier established on the Belgium shallow-water platform. Two Brigantian sequences 10 and 11 are identified and, despite the prograding Variscan Orogen, the two lower Namurian (Pendleian, Arnsbergian) sequences 12 and 13. The results demonstrate the successful application of sequence stratigraphy in a deeper-water basin, show that sea-level changes overrule the general, more gradual tectonic development of the basin, and prove the Palaeotethyan, if not global isochroneity of Mississippian sequences

Endorsing Darwin: global biogeography of the epipelagic goose barnacles Lepasspp. (Cirripedia, Lepadomorpha) proves cryptic speciation

It was Darwin that noted the large intraspecific diversity of the goose barnacle Lepas Linnaeus, 1758 and thought about distinct regional varieties. Today, biogeographic compartmentation is known from marine species, but data from globally occurring species remain scarce. We analysed inter- and intraspecific divergence within the epipelagic rafter Lepas from tropical and temperate oceans by means of two mitochondrial and one nuclear DNA marker. Besides phylogenetic relations, we resolved biogeography and controlling factors. Inhabiting the Southern Hemisphere, Lepas australis Darwin, 1851 shows separate populations from coastal Chile and from circum-Antarctic waters, most probably related to temperature differences in the current systems. The cosmopolitan Lepas anatifera Linnaeus, 1758 displays four regional subgroups (coastal Chile, Northeast Pacific/Oregon, the Southern Hemisphere Indopacific, and the Atlantic), and a global group, which might be an ancestral stem group. The differentiation reflects vicariance effects rooted in geological history: the closure of the Neogene Tethys in the Middle East and at the Panama Isthmus, the installation of the cool Benguela Current, differing Pleistocene currents and temperatures, and modern current systems. The extreme ecological generalists Lepas anserifera Linnaeus, 1767 and Lepas pectinata Spengler, 1793 are not differentiated, and might represent true global species. In conclusion, compartmentation of the oceans acts at the species level according to ecospace limits. For Lepas, the multitude of barriers favours allopatric speciation

Uppermost Famennian bryozoans from Ratingen (Velbert Anticline, Rhenish Massif/Germany) - Taxonomy, facies dependencies and palaeobiogeographic implications

Three bryozoan species are described from the uppermost part of the Velbert Formation (uppermost Famennian, Strunian) from the classical section Ratingen-Cromford (northwestern flank of Velbert Anticline, western Rhenish Massif, Germany). The described fauna includes one new genus Ratingella gen. n., one new species Crustopora fistulosa sp. n., and one species in open nomenclature, Nikiforovella sp. The hitherto known bryozoans from the Strunian of the Velbert Anticline constitute the most important bryozoan fauna from the Famennian 'Condroz Shelf', bordering on the southwestern coast of Laurussia between southwestern England and Pomerania (northern Poland). Coinciding, it is the most diverse European bryozoan fauna from that time slice. Facies differences along the northwestern flank of the Velbert Anticline between a clear-water ramp segment in the southwest and a marl ramp segment in the northeast are responsible for a completely different faunal association. Encrusting taxa diminish towards the north, while erect growing, branched taxa predominate and the general diversity increases. The studied fauna points to connections with the Asiatic part of Russia, Kazakhstan, and China and implies a general Palaeotethyan character for latest Famennian bryozoans in Eurasia

Late Moscovian (mid-Pennsylvanian) rugose corals from Wadi Araba (Egypt, Eastern Desert): Taxonomy, palaeoecology and palaeobiogeography

An important late Moscovian rugose coral association is described from the Rod El Hamal Formation of the Wadi Araba area (northern Eastern Desert, Egypt). The upper part of the formation yielded a moderately abundant but poorly diversified coral fauna composed of large dissepimented solitary rugose corals. In total, six species belong to the Bothrophyllidae and the Geyerophyllidae, including three new species: Bothrophyllum suezensis, Bothrophyllum cylindricum, and Amygdalophylloides omarai. Three undeterminable Bothrophyllidae taxa are left in open nomenclature. The corals were attached to the soft substrate by talons and rootlets, either rooted and growing upward as mud-stickers or as secondary recliners. They show frequent rejuvenations and constrictions. Encrustation and/or bioerosion are scarce. Carbonate microfacies indicate a habitat in littoral and inner neritic zones adjacent to a low terrigenous hinterland. Colonial taxa are missing and tabulate corals are rare. The corals from the Rod El Hamal Formation are the only example of a late Moscovian coral fauna on the southern margin of the Palaeotethys, that is to say along the northern margin of Gondwana. The association shows similarities with northwestern Spain (Cantabrian Mountains), the Donets and Moscow basins, and thus a general attribution to the Palaeotethys realm. (C) 2018 Elsevier Masson SAS. All rights reserved

Kasimovian (late Pennsylvanian) cornute rugose corals from Egypt: taxonomy, facies and palaeogeography of a cool-water fauna from northern Gondwana

Abstract A strongly endemic Upper Pennsylvanian (Kasimovian) rugose coral association consisting of small, mostly non-dissepimented, simple structured and poorly diversified species is studied from the lower member of the Aheimer Formation (Western side of the Gulf of Suez, Egypt). The unit is composed of grey, silty mudstone intercalated with thin, ferruginous, silty dolostone–limestone and calcareous siltstone beds. Ten taxa from four families were identified. Four species of the Antiphyllinae are new; Actinophrentis crassithecata n. sp., Lytvolasma aheimerensis n. sp., L. paraaucta n. sp. and Monophyllum galalaensis n. sp. Besides, Rotiphyllum exile de Groot, 1963 and Bothrophyllum okense Kossovaya, 2001 were identified; four taxa remain in open nomenclature (Lytvolasma cf. canadense, Zaphrentites cf. parallela, Zaphrentites sp. and Ufimia sp.). Rejuvenation, encrustation and bioerosion phenomena are rare. Attachment structures during mature stages are not evident; attachment scars in the apical parts are also rare. Growth patterns and embedding in the muddy deposits indicates that the corals lived as mudstickers in soft substrate. Recrystallization, dolomitization and ferrugination of open pore spaces inside the corals are the most common diagenetic features. The corals from the lower Aheimer Formation represent a typical cyathaxonid fauna that was adapted to high clastic input and turbid waters in a restricted, sheltered, episodically storm-swept inner ramp environment in an embayment of the southern shelf of the Palaeotethys. A time-averaged ramp model shows a regressive development from a mixed carbonate–siliciclastic open inner ramp setting during the Moscovian to the restricted inner ramp of the lower Aheimer Formation (Kasimovian) and following peritidal to fluvial environments of the Gzhelian. General and local palaeoclimatic considerations indicate cooling. Besides relations to northern Spain that root Egypt in the western Palaeotethys, connections existed via the Donets Basin (and the southern Urals) to the Cordilleran–Arctic–Uralian realm which is a cool water province during the Lower and Middle Permian. The Egyptian fauna appears to be a precursor of the anti-tropical cyathaxonid fauna of the latter time slice and also of the Lower Permian cool-water faunas of the east Cimmerian peri-Gondwana terranes

Facies and palaeoecology of the late Visean Actinopteria Black Shale Event in the Rhenish Mountains (Germany, Mississippian)

The isochronous, mid-Brigantian (latest Visean) Actinopteria Black Shale is intercalated in between upper Visean calciturbidites within the northern part of the Rhenish Mountains (Germany). It shows characteristic mass-occurrences of the eponymous bivalve Ptychopteria (Actinopteria) lepida (Goldfuss). The case study of a classical, exceptionally well-preserved outcrop in the Ludenscheid Syncline documents the facies and palaeoecology of this event horizon. Hitherto, sediments had been regarded as deep-marine anoxic deposits, resulting from pelagic rain. Now, microfacies analysis of the mostly silicified mudstones revealed a heterogeneous sedimentary facies, showing ample evidence of current-driven micro-event deposits regarded as mud turbidites. Various but simple ichnofabrics indicate mostly dysoxic conditions of the soupy sediment. Discussion of palaeobiological constraints proves the earlier assumed pseudoplanktic mode of life for Ptychopteria (Actinopteria) lepida and contradicts epibenthic colonisation by that bivalve. Mass-occurrence might be a compaction artefact, but occurrence on few distinct bedding planes in an interval several centimetres thick is related to an extraordinary complete sedimentary record that protected the paper pectens from erosion. This variant of a taphonomic epibole is termed maximum completeness epibole. In the case of the Actinopteria Shale, in sequence stratigraphic terms a transgressive systems tract, this bioevent is postulated to represent the maximum flooding surface with minimum sedimentary input and reworking