Ultrastructure and affinity of Lower Carboniferous megaspores from the Moscow Basin, Russia

Ten megaspore species isolated from Moscow Basin lignites of Lower Carboniferous (Viséan) age have been studied by scanning and transmission electron microscopy (SEM and TEM). These species belong to seven megaspore genera: Lagenicula, Sublagenicula, Crassilagenicula, Setosisporites, Zonalesporites, Caudatosporites, and Cystosporites. Megaspores of the genus Caudatosporites have only been described previously from the Duckmantian (Westphalian B); a new species is duly erected. The ultrastructure of megaspore walls from the genera Crassilagenicula and Zonalesporites has not been previously described. This study also places them in context with other contemporaneous megaspores. The study shows that during the Viséan, in the Moscow Basin, megaspores expressed a similar wall ultrastructure despite large differences in external appearance. The genus Crassilagenicula may represent a group of megaspores from plants that had evolved from those bearing gulate megaspores here typified by Lagenicula acuminata, Setosisporites brevispinosus, and Sublagenicula hirsutoida. Zonalesporites brasserti also appears to show affinities to this group, and may be representative of a plant species in a transitional state between the Lagenicula bearing lycopsids and those more isoetalean in nature.     

A new microsporangiate organ from the Lower Carboniferous of the Novgorod Region,Russia

A new species of the genus Telangiopsis, T. nonnae O. Orlova et Zavialova, was described on the basis of a microsporangiate organ from the Lower Carboniferous deposits of the Novgorod Region. The morphology of branching fertile axes, synangia, and sporangia was thoroughly studied. The three-dimensional system of fertile axes branches monopodially; ultimate axes bear numerous connivent bunches of synangia, which consist of three to six basally fused elongated ovate sporangia. The morphology and ultrastructure of prepollen grains were studied, which were extracted from the rock matrix surrounding the sporangia. The two-layered exine includes a well-developed endexine and an alveolate ectexine, with one-three rows of large thin-walled alveolae. The new species was compared with other Early Carboniferous microsporangiate organs.     

Enigmatic Fossils from the Lower Carboniferous Shrimp Bed,Granton, Scotland

The Lower Carboniferous (Visean) Granton Lagerstätte (Edinburgh, Scotland) is principally known for the discovery of the conodont animal, but has also yielded numerous crustaceans and other faunas. Here we report on small branching colonies, reaching 10 mm in length. They are small, erect, arborescent, and irregularly branched with predominant monopodial and dichotomous growth. They bud in a single plane. In one specimen the wall microstructure is well preserved and it is composed of evenly spaced, linear fibers, running parallel to the axis of the stems, and connected by transverse bars. We discuss possible biological affinities of these organisms; we consider algal, poriferan, hydrozoan and bryozoan affinities. The general pattern of branching, presence of fan-like structures (interpreted here as possible gonophores) and microstructure suggests affinity to Hydrozoa, affinity to non-calcifying algae is less likely. Assuming hydrozoan nature; the microstructure might suggest affinities with the extant family Solanderiidae Marshall, 1892 that possess an internal chitinous skeleton. The EDS analysis shows that fossils discussed here are preserved as phosphates. The skeletons were probably not mineralized, the presence of phosphorus suggests that the colonies were originally composed of chitin. We describe these organisms as Caledonicratis caridum gen. et sp. nov. (Solanderiidae?, Capitata?). Colonies of C. caridum gen et. sp. nov. sometimes encrust the exuviae of crustaceans, which very probably lived in fresh to brackish water thus indicating a likely habitat of Caledonicratis.     

Arachnids from the Carboniferous of Russia and Ukraine,and the Permian of Kazakhstan

New finds of Late Palaeozoic arachnids, based on three well-preserved carapaces from the Carboniferous of Russia and Ukraine and one complete, albeit poorly preserved, specimen from the Permian of Kazakhstan, are described. The spider genus Arthrolycosa is reported from the Late Carboniferous (Late Pennsylvanian: Kasimovian–Gzhelian) of Chunya in the Tunguska Basin of Siberia; it is the first find of a spider outside the Carboniferous tropics. Another fossil assigned to the same genus comes from the Late Carboniferous (Early Pennsylvanian: Bashkirian) of Kamensk–Shakhtinsky in the Donets Basin of Russia; it is probably the oldest fossil spider known. A thelyphonid (whip scorpion) carapace is described from the Late Carboniferous (Late Pennsylvanian: Kasimovian) of the adjacent Lugansk Province of the Donets Basin of Ukraine.     

Early Carboniferous plants of the Arkhangelsk Region,Russia

Eight species of fossil plants are described for the first time from the Lower Carboniferous of the Arkhangelsk Region. One of these species, Adiantites lisitzynii O. Orlova et Jurina, is new. The taxonomic composition of the assemblage of 20 species indicates a woody vegetation of the Euramerian aspect. The rich assemblage recovered for the first time from terrigenous deposits of the Arkhangelsk Region dates them to the Visean (Early Carboniferous).     

Taphonomy of Lower Carboniferous crinoids from the Hook Head Formation, Ireland

Ausich, W.I. & Sevastopulo, G.D. 1994 10 15: Taphonomy of Lower Carboniferous crinoids from the Hook Head Formation, Ireland.
Lower Carboniferous strata at Hook Head, County Wexford, Ireland, record tempestite deposition on a mixed carbonate and siliciclastic shelf-ramp. Crinoidal remains occur in all facies, which allows for a comparative taphonomic analysis of crinoid preservation. Preservation of crinoid crowns was controlled by a balance between mean storm intensity and frequency. The best preservation occurs at moderate depths. Taphonomic resistance among Hook Head crinoids is interpreted as follows (from most to least resistant to disarticulation): monobathrid camerates -cladids - diplobathrid camerates — flexibles (with Platycrinites and Dichocrinus disarticulation more like cladids). Crinoidea, taphonomy, preservation, Lower Carboniferous, Ireland .     

The First Stem Tetrapod from the Lower Carboniferous of Gondwana

The first stem tetrapod from Gondwana, Ossinodus pueri gen. et sp. nov, is described from fragmentary material that includes a skull table and many important parts from the postcranial skeleton. It was recovered together with a typically non-marine to marginal (near) marine fish fauna from the Lower Carboniferous (mid Viséan) Ducabrook Formation, Queensland, Australia. Phylogenetic analysis hypothesises that Ossinodus belonged to a clade that includes Whatcheeria and Pederpes , positioned on the stem of the crown tetrapods, one step crownward of Tulerpeton . Hind limb morphology suggests that small specimens of Ossinodus were primarily aquatic but that larger ones were less so.     

A Probable Moss from the Lower Carboniferous of the Forest of Dean, Gloucestershire

A single sterile specimen of a moss-like plant is describedfrom the Drybrook Sandstone (Lower Carboniferous) of the Forestof Dean, Gloucestershire. Comparison is made with fossil andliving mosses and as a result it is referred to the Bryalesand named Muscites plumatus sp. nov. The records of other palaeozoicmosses are considered but many are so doubtful that the presentspecimen is believed to be the oldest moss known.     

A bryozoan buildup from the Lower Carboniferous of North Wales

A carbonate buildup dominated by trepostome Bryozoa is described from Dinantian (Asbian) strata near Llandudno in North Wales. A three-phase ecological succession is recognised within the buildup: (i) a basal diverse community with fenestrate, ramose, encrusting trepostome and cystoporate bryozoans in a mud rich wackestone; (ii) a bulk facies, dominated by encrusting and foliaceous, trepostome bryozoans in a fine packstone, and (iii) a thin capping phase, dominated by unilaminar, encrusting trepostome bryozoans in a slightly coarser lithology, including skeletal debris derived from the mound top and possible flanking beds. The buildup probably had topographic relief and developed in a shallow marine environment. The internal tripartite zonation reflects the growth of the structure into a shallower, higher energy regime, with the capping beds being deposited just below wave base. The buildup developed to the north of St. George's Land, on a carbonate shelf edge bordering the deeper basinal facies of the Irish Sea Basin. Dinantian, Asbian, buildup, trepostome Bryozoa, Foraminifera, corals, calcareous algae, Carboniferous, North Wales .     

Kulm trilobites (Lower Carboniferous) from S-China

Some trilobite remains are described from the Lower Carboniferous/Mississippian (Tournaisian/Viséan boundary) of S-China, representing two species:Liobole (Liobole) devuysti n. sp. andLiobole (Sulcubole) xiangzhouensis n. sp.Liobole is a typical member of the central European Kulm Facies and index fossil for the Erdbachian. For the first time, twoLiobole species are recorded from outside of Europe. They demonstrate that a passage existed between Europe and East Asia across the Palaeotethys through which Kulm trilobites have occupied new geographical regions.      

An enigmatic chordate from the Lower Carboniferous Granton 'shrimp-bed' of the Edinburgh district, Scotland

A new soft-bodied chordate, Conopiscius clarki gen. et sp. nov., with V-shaped scales covering the trunk, and a pair of cone-shaped structures in the head, is described from the Lower Carboniferous of Granton, Edinburgh. It occurs in the 'shrimp-bed' which, although dominated by eumalacostracan crustaceans, has also yielded exceptionally preserved examples of other taxa including the soft parts of conodonts. The new animal may represent a jawless craniate with affinities to Jamoytius. The parallels between this and other faunas yielding similar chordates (e.g. Jamoytius ) may be taphonomic rather than environmental.     

The first dinosaur egg from the Lower Cretaceous of Western Siberia,Russia

The Lower Cretaceous Ilek Formation in Western Siberia (Russia) has yielded various vertebrate fossils, including skeletal remains of dinosaurs. Here we report on a fragmentary theropod egg from the vertebrate locality Shestakovo 3 of the Ilek Formation in Kemerovo Province. We assign the specimen to the oogenus Prismatoolithus (oofamily Prismatoolithidae) as Prismatoolithus ilekensis oosp. nov., on the basis of the following unique combination of characters: ovoid-shaped egg; thin eggshell 300–330 μm thick; angustiprismatic morphotype; eggshell with three different layers; gradual transition between mammillary layer and prismatic layer; abrupt contact between prismatic layer and external layer; mammillary layer to prismatic layer to external layer thickness ratio is 1:3:0.6; prismatic layer with ill-defined squamatic texture; angusticanaliculate pore system; and smooth outer surface. Like other Early Creataceous Prismatoolithus, the egg of Prismatoolithus ilekensis oosp. nov. was laid by a small bodied theropod dinosaur (troodontid or primitive bird) and this taxonomic attribution is supported by results of our phylogenetic analysis. Prismatoolithus ilekensis oosp. nov. is the first Early Cretaceous ootaxon from Russia.

urn:lsid:zoobank.org:act:734EAD40-86C3-488B-A61E-B5FF7378BC0E     

Sublethal injuries in non-marine microconchid tubeworms from the Lower Carboniferous of West Virginia,USA

More than 10,000 non-marine microconchid tubeworms (order Tentaculita) from the Lower Carboniferous (Mauch Chunk Group) of West Virginian, USA, have been inspected with respect to the occurrence of specimens having repaired injuries. The inspection showed that only nine specimens bear distinct regenerations of their tubes which constitute only 0.08% of the total specimens. This value, although much lower than that obtained from other encrusting tentaculitoid tubeworms, is very similar to that calculated before for the thousands of Early Devonian planktonic tentaculitids. This clearly indicates that sample size (specimen number) is critical for obtaining the reliable data about the proportion of regenerated vs. unaffected specimens. The sublethal injuries present in these few individuals probably resulted from failed predation, most probably by grazing fishes. However, the repaired injuries only indicate that some individuals survived but do not provide any information about the predation intensity on the group in the given paleoenvironment. Microconchids encrusted a given substrate in large quantities, so grazing fishes may have easily removed the majority of individuals, leaving no trace of predation activity in the Early Carboniferous, non-marine paleoenvironments of what is now West Virginia.     

Radiizonates arcuatus, a distinctive new miospore species from the Lower Carboniferous of Western Gondwana

A new species of trilete zonate miospores, Radiizonates arcuatus, is established for Lower Carboniferous Western Gondwanan forms hitherto ascribed misguidedly to Radiizonates genuinus (Jushko) Loboziak and Alpern (1978), a Russian Lower Carboniferous species. The latter binomen is, moreover, not a valid combination and is more correctly designated as Vallatisporites genuinus (Jushko) Byvsheva, 1980. R. arcuatus is, from records to date, confined to westerly parts of Gondwana (Brazil, North Africa and Middle East), in which it is characteristic of Early Carboniferous strata, albeit with some slightly older and slightly younger occurrences.