We report on well-preserved upper and lower jaws found inside the body chambers of two specimens of Didymoceras nebrascense (Meek and Hayden, 1856) from the Upper Cretaceous Pierre Shale of the USA. The finds are described and compared to existing material, and their possible functions are discussed.

Cherts and silicified dolostones of the ca. 1600 Ma Dahongyu Formation (uppermost Changcheng Group) from North China contain well-preserved microfossils. Cyanobacteria filaments and coccoids dominate the studied Dahongyu microbiota in the Jixian section. These microfossils show the characteristics of endobenthic, epibenthic, and allochthonous microfossils, which illustrated well a vertical distributional view of an intertidal microbiota. Large numbers and size of allochthonous microfossils are the distinguishing characteristics of this new microbiota. A few of these possess ornaments or odd morphology, which suggest their potential eukaryotic nature. Through regional comparisons, it is revealed that there was significant regional disparity within the Yanshan Basin of microbiotas during deposition of the Dahongyu Formation. The newly studied Dahongyu microbiota is similar to the microbiota from the underlying Changcheng Group, with only slight differences. The absence of typical eukaryotes and the emergence of unique microfossils (especially small fusiform microfossils) make the Dahongyu Formation and the subsequent strata of the Jixian Group distinct from contemporaneous eukaryote-bearing strata.

In the Dahongyu assemblage, 19 species were recognized, six species were identified informally and seven species were identified in open nomenclature. One new taxon of microfossil was described: Xiaohongyuia sinica Shi and Feng new genus new species.

The fixing organ of the Precambrian macroalga was briefly described by most researchers as a holdfast or rhizoid, suggesting a fixation structure and/or tissue differentiation. An Ediacaran macroscopic alga, Discusphyton whenghuiensis n. gen. n. sp., with a complex disc-like holdfast and an unbranching thallus, has been collected, together with abundant and diverse macrofossils (i.e., the Wenghui biota) in black shales of the upper Doushantuo Formation (~560–551 Ma) in northeastern Guizhou, South China. The Wenghui biota lived in a relatively low-energy marine environment and was preserved in situ or nearby their growth position. Morphologically, the macroalgal thallus, including the compressed lamina and cylindrical stipe, might have been suspended in the water column for photosynthesis. Its holdfast, a rare fixing form, is complex in structure and construction, consisting of a globular rhizome and a discoidal rhizoid. The large-sized discoidal rhizoid is regarded as a flat-bottomed and dome-shaped organ to attach the macroalga on the water-rich muddy seafloor. The globular rhizome, expanded by a thallus on the substrate, was originally harder and spherical nature within the dome-shaped rhizoid. It may have been an important organ as a steering knuckle to connect between the stipe and the rhizoid. The macroscopic metaphyte D. whenghuiensis n. gen. n. sp. shows the appearance of complex holdfast in morphology and bio-functions. However, not enough is known, in the absence of more information, to decipher the phylogenetic affinity of D. whenghuiensis n. gen. n. sp. and the origin of a discoidal rhizoid.

The scolecodont genera Nereidavus Grinnell, 1877, and Protarabellites Stauffer, 1933, have been used for several different fossil polychaete taxa over the years. Nereidavus is here considered a nomen dubium, as the holotype of the type species is lost and the original information is insufficient for identification. Protarabellites is reevaluated and constitutes, besides Ramphoprion, a second genus in the family Ramphoprionidae. The “paratype” of N. varians (named Ramphoprion sp. in this paper), and the holotype of P. humilis are redescribed.

Extensive collections of Pennsylvanian marine gastropods from 20 marine units in the Appalachian Basin contain 227 recognizable taxa. Twenty-two new species and subspecies are recognized including Bellerophon (Bellerophon) laticallis, B. (B.) graphicus varicallis, B. (Pharkidonotus) breyeri, Knightites (Cymatospira) montfortianus discordis, K. (Retispira) fascireticulatus, Colpites lirata, Abylea formosa, A. paradoxus, A insolitus, Spiroscala decorata, Euconospira equisita, Neilsonia invisitata, Worthenia parvula, Gosseletina nodosa, Glyptotomaria (Dictyotomaria) concinna, G. (D.) facta, G. (D.) decora, Phymatopleura preclara, Callispira grossa, Ceraunocochlis? subulata, Streptacis? ingens, and S.? complanata.

Correlation of marine stratigraphic units within the collection area are discussed. Zonation on the basis of pseudozygopleurid taxa, following that of Anderson et al. (1989), is presented as well as mention of characteristic taxa of the various series.

Supposed Upper Proterozoic strata in the southwest Taoudeni Basin, Guinea and Senegal, and from the Mauritanide fold belt, Mauritania, have yielded mostly poorly preserved small skeletal fossils of metazoan and protistan origin. Problematic, but possible echinoderm material and spicules of the heteractinid sponge Eiffelia dominate the Taoudeni Basin assemblage. The age of the material is not certain but the paleontologic data suggest an Early Cambrian age for the stratigraphically lowest faunas, and a Middle Cambrian age is possible for the stratigraphically highest collections.

The emended descriptions of the genus Amphitriscoelus and the species A. waringi Harris and Hodson are given, and a new species is proposed (A. pluriloculata). These rudist bivalves are derived from a thick Lower Cretaceous sequence of carbonate sediments interlayered with siliciclastic, volcaniclastic, and volcanic rocks in southwestern Mexico, near Huetamo, in the State of Michoacan. The species belong to a recently discovered rich fauna containing other rudists, nerineid gastropods, orbitolinid foraminifers, and calcareous algae. The fauna shows a close affinity with the Amphitriscoelus fauna of northern South America. Similar assemblages are also present in Texas, Cuba and other Mexican localities. The wide distribution of the fauna allows interpretation of paleogeographic relations among all the regions as well as interpretation of paleoecological similarities. The existence of an homogeneous large faunistic province during the Early Cretaceous is suggested.

Three fossil taxa of megapodagrionid damselflies are described and figured from the Paleogene localities in Europe on the basis of isolated wings. Eckfeldia superstes (Wappler, 2003) gen. nov. is described from the laminated mudstones of middle Eocene age from Eckfeld Maar, Germany. Furagrion jutlandicus (Henriksen, 1922) gen. nov. is recorded from the laminated claystones of lowermost Eocene age from the Ølst and Fur-Formation, Denmark, and an undetermined megapodagrionid damselfly is recognized from middle Eocene strata. Taphonomy and color preservation in the fossils are briefly considered. Characters used for phylogenetic analyses in extant and fossil Megapodagrionidae are discussed. The biogeographic and paleoecological implications of the new European fossils are briefly discussed.

Recent studies of drill-cores and outcrops have resulted in the discovery of previously unknown, taxonomically diverse, graptolite faunas in the late Middle (Mohawkian) and early Late Ordovician (Cincinnatian) strata in the Cincinnati region, the type area of the Cincinnatian Series. These faunas contain several zonal indices and other biostratigraphically important species that are used for close correlation with the standard graptolite zone succession in New York and Quebec. The new data show that the base of the Cincinnatian Series in its type area is near the middle of the Climacograptus (Diplacanthograptus) spiniferus Zone. Significantly, about a dozen Cincinnati region graptolite species are shared with apparently coeval strata in the standard Australian graptolite zone succession in Victoria, and this key faunal evidence indicates that the base of the typical Cincinnatian corresponds to a level near the middle of the Climacograptus (Climacograptus) baragwanathi Zone (Ea2) of the Eastonian Stage. This represents a considerable revision of some recently published correlations of the basal Cincinnatian in terms of the Australian graptolite zone succession.

A distinctive spiral unilaminate cyclostome bryozoan, recently discovered in the Eocene Castle Hayne Limestone Formation of eastern North Carolina, is described as Crisidmonea archimediformis new species. Colonies have a thickened spiral axis bearing systems of bifurcating branches. When worn and stripped of their branches, the resistant axes closely resemble the familiar screws of the Carboniferous to Permian fenestrate bryozoan genus Archimedes. However, the Eocene screws are shorter and become more loosely coiled with growth, corresponding to a helicospiral rather than a helical form. The paleoenvironment inhabited by C. archimediformis colonies is inferred to have been on the shallow (< 30 m depth) margin of an open marine, waveswept embayment. Autozooid distribution and the gradient of increasing apertural size from branch reverse to frontal sides in C. archimediformis resemble those of the living cyclostome Exidmonea atlantica and suggest colonial water currents that flowed upwards and inwards through the spiral colony. Polyascosoecia, a genus closely related to Crisidmonea, is shown to be an objective junior synonym of Reteporidea, and the new genus Polyascoeciella (type species Idmonea foraminosa Reuss) is introduced for species with exterior-walled gonozooids that were previously assigned to Polyascosoecia.

New discoveries of trigonioid bivalves are documented from three areas in the Antartic Peninsula: the Fossil Bluff Group of Alexander Island, the Latady Formation of the Orville Coast, and the Byers Group of Livingston Island, South Shetland Islands. Eleven taxa are described, representing six genera or subgenera. The faunas are characterized by genera including Vaugonia (Vaugonia), the first Early Jurassic trigonioid recognized on the continent; Vaugonia (V.) and V. (Orthotrigonia?) in the Late Jurassic; and Iotrigonia (Iotrigonia), Myophorella (Scaphogonia), and Pterotrigonia (Pterotrigonia), which span the Jurassic–Cretaceous boundary, reaching the Berriasian stage. The following species are new: Pterotrigonia (P.) cramei n. sp., Pterotrigonia (P.) thomsoni n. sp., Vaugonia (V.) orvillensis n. sp., and V. (Orthotrigonia?) quiltyi n. sp. The faunas show affinities with those of New Zealand and southern Africa. Trigonioids characterize the shallower marine biofacies in the Jurassic of the Antarctic and reflect the principal shallowing events in the history of the region.

In a recent article, Narbonne et al. (1991) documented that the stratigraphic range of the chondrophorine Kullingia delicata continues above the the uppermost Precambrian (Vendian) into the lowermost Cambrian (Placentian Series) of the Avalonian faunal province. The revised text published in the Journal of Paleontology includes several references to Scenella Billings, 1872, as a Cambrian chondrophorine. This classification is in error and unfortunately serves to reinforce several recent reports that conclude that Scenella is a chondrophorine rather than a helcionacean mollusk.

The Hapsidopareiontidae are microsaurian amphibians known only from the Lower Permian of the U.S. The hapsidopareiontid skull has a large temporal embayment that occupies most of the area of the cheek, in which the quadratojugal is either absent (Hapsidopareion) or present and greatly reduced (Llistrofus). the unique holotype skull of Llistrofus pricei is well preserved in soft clay. It was originally prepared and described in dorsal view only, but has now been prepared completely free of the matrix. This permitted the first description of the palate, occiput and mandible along with a redescription of the rest of the skull, resulting in substantial emendation of previously published descriptions. Comparison with the eight known complete and partial skulls of Hapsidopareion lepton demonstrates that the two genera are much more similar than had been recognized earlier. Their continued separation is advocated, however, based on size difference, a small number of osteological differences, and the difficulty of obtaining comparably detailed morphological information for Hapsidopareion, which is less well preserved than the Llistrofus specimen. the new morphological information, combined with results of recently published cladistic analyses, suggests that Hapsidopareion and Llistrofus are the only microsaurs that can at present be assigned to the Hapsidopareiontidae. the large temporal embayment of hapsidopareiontids might be thought to have significant functional implications, possibly including “escape” of jaw adductor musculature onto the skull roof. Detailed consideration of this possibility reveals morphological evidence to the contrary, however, and the functional implications of the embayment remain uncertain.

Trilobites assigned to 14 genera and 14 species are reported from basal part of the Deadwood Formation in the Black Hills of South Dakota. Six additional taxa are left in open nomenclature. One new species, Cedarina dakotaensis, is described. These trilobites are assigned to a new zone, the Cedarina dakotaensis Zone, named after the most abundant trilobite species.

Species of Cedarina and Modocia are the most abundant in the Cedarina dakotaensis Zone, accompanied by less common specimens of species of Arapahoia, Menomonia, Hardyoides, Welleraspis, Kormagnostus, and Kingstonia. Cedarina dakotaensis and Modocia centralis are the most abundant species in the nearshore sandstone lithofacies, whereas Arapahoia spatulata is the predominate taxon in the offshore limestone lithofacies.

The fauna of the Cedarina dakotaensis Zone (which lacks species of Cedaria) occupies the biostratigraphic interval of the traditional Cedaria Zone of the Marjuman Stage. Trilobites from the Cedarina dakotaensis Zone can be used to correlate the basal part of the Deadwood with coeval strata elsewhere in North America.

Species of Ivanovia (Codiaceae or Udoteaceae, Chlorophyta) have traditionally been characterized as phylloid or leaf-like. Extraordinarily well preserved specimens of I. tebagaensis in limestone from the Upper Permian of southern Tunisia indicate that the thallus was cyathiform or cup-shaped, similar to the broadly conical codiacean Calcipatera and to living Udotea cyathiformis. Ivanovia also shared with Calcipatera the same general membrane structure consisting of bilateral cortices with palisades of utricles, now filled with micrite, and a medulla of tubular coenocytes, now filled with sparry calcite mosaic. A cyathiform thallus would have had an inner and an outer cortex and those of I. tebagaensis were dimorphic. The utricular structure as usually seen in thin sections using transmitted light is much clearer when viewed on polished surfaces of hand specimens using reflected light. Commonly occurring fused membranes suggest that the thalli reproduced vegetatively by budding. The complexity and regularity of the I. tebagaensis membrane structure strongly suggest that a model which proposes that Ivanovia is simply a diagenetic stage in the fossilization of the red alga, Archeolithophyllum, is invalid.

Permian Orthotetoidea on Hydra belong to the genera Cyndalia Grant (1993a), Goniarina Cooper and Grant (1969), Derbyia Waagen (1884), Diplanus Stehli (1954), Schuchertella Girty (1904), Sicelia Merla (1934), and Tropidelasma Cooper and Grant (1969). Hydra has the most complete Permian section in the Western Tethys, 500 m thick and ranging in age from Asselian to Dorashamian. These are the youngest silicified Permian brachiopods west of China.

Conodont faunas from the upper part of the Wadleigh Limestone, Alexander terrane, southeastern Alaska, are of Frasnian to early Famennian age and include the new taxa Polygnathus aspelundi nanus n. subsp., Polygnathus decorosus dutroi n. subsp., Polygnathus elegantulus sparus n. subsp., Polygnathus gracilis n. subsp. A, Polygnathus n. sp. A, Palmatolepis subrecta youngquisti n. subsp., and Icriodus subterminus uyenoi n. subsp. Four distinct age-determined faunal assemblages are recognized. The lowest is assigned to the Lower Palmatolepis rhenana Zone (the chronozones of Ziegler and Sandberg, 1990, are treated herein as time-rock equivalent assemblage zones). The next is exposed on three small islands just south of Wadleigh Island and is correlated with part of the Lower to Upper Palmatolepis rhenana Zones. The third assemblage, on the eastern side of Wadleigh Island from close to the top of the section, is correlated with part of the Palmatolepis linguiformis Zone. Nearby and overlying this is the fourth assemblage, which is correlated with part of the Lower Palmatolepis triangularis Zone and thus appears to be within the lower Famennian. These Wadleigh Limestone conodont faunas have affinities with faunas from equivalent horizons of the cratonic regions of the Northwest Territories and Alberta in Western Canada and to other faunas globally. The more provincial conodont taxa lend weak but positive support to brachiopod faunal evidence that places the Alexander terrane close to the North American craton during the Late Devonian.

Late Triassic coniferous species of silicified woods are described from the Tronquimalal Group, Llantenes Depocenter of the Neuquén Basin, southern Mendoza Province, Argentina. The new species Agathoxylon cozzoi and Agathoxylon lamaibandianus Crisafulli and Herbst, 2011 described in this study were found in proximal volcaniclastic facies deposited in alluvial fans and proximal braided river plains of the Chihuido Formation, which is the basal unit of the Group. The species A. lamaibandianus Crisafulli and Herbst, Protojuniperoxylon ischigualastense (Bonetti, 1966) Bodnar and Artabe, 2007, and the new species Cupressinoxylon llantenesense also described in this study were collected from the upper fluvio-deltaic plain and delta-plain deposits that prograded into a large, meromictic and wedge-shaped lake of the overlying Llantenes Formation. The Tronquimalal Group yields abundant and well-known Triassic plant remains of the Southern Gondwana “Dicroidium Flora,” although it also contains typical early Jurassic taxa displaying age affinities with other Argentinean “Florian Stage” communities of Late Triassic (Norian–?Rhaetian). The lignotaxa described from both units of the Tronquimalal Group may all together represent coniferous forests of the extratropical area of the Southwestern Province of Gondwana. Deciduous conifer forests associated with herbaceous and shrub communities dominated by ferns and smaller corystosperms, and other taxa including the Linguifolium leaves within the Llantenes Depocenter environments, were developed on the western margin of the continent under seasonal temperate-warm and humid to sub-humid climate with a marine influence from the west.

Mid-Carboniferous (upper Chesterian–lower Atokan) rocks exposed north of the Snake River Plain in east-central Idaho are assigned to the Arco Hills, Bluebird Mountain and lower Snaky Canyon formations (ascending order). In the southern Lemhi Range, calcareous algae and associated microproblematica from these rocks include representatives of at least 13 genera and genus-level taxa within the Dasycladaceae, Aoujgaliaceae, Ungdarellaceae, and incertae familiae. Local appearances of Masloviporidium delicata and Donezella lutugini are early Morrowan or younger as determined independently by studies of associated foraminifers and conodonts. Beresella polyramosa and Komia abundans are locally restricted to Atokan rocks. These findings are consistent with compiled data on worldwide stratigraphic distributions of these taxa, and suggest that certain Upper Paleozoic calcareous algae may be of limited value in biostratigraphic correlation.

North American Pacific Slope deposits of Coniacian to Maastrichtian age have yielded eight biostratigraphically useful species of Anchura: A. (Helicaulax?) popenoei new species, Coniacian; A. halberdopsis new species, early Campanian; A. callosa Whiteaves, 1903, early Campanian; A. falciformis (Gabb, 1864), late early to middle Campanian; A. phaba new species, middle to late Campanian; A. ainikta new species, middle to late Campanian; A. gibbera Webster, 1983, late Campanian to early Maastrichtian; A. baptos new species, late Maastrichtian to early Danian. In addition, two other possible species are A. nanaimoensis (Whiteaves, 1879), middle to late Campanian, and Anchura? new species, late Maastrichtian. These species together with two additional Turonian species, A. (Helicaulax) tricosa Saul and Popenoe, 1993, and A. (H.) condoniana Anderson, 1902, allow the definition at least eight Late Cretaceous Anchura zones for the Pacific Slope. These zones have durations of 1.5 m.y. to 4 m.y.

Anchura (H.?) popenoei from northern California appears most closely related to A. (Helicaulax) tricosa Saul and Popenoe, 1993, of Turonian age from southern California. Anchura callosa, A. falciformis, A. nanaimoensis, and A. phaba appear to be closely related based on sculptural elements, as does A. gibbera despite having an anterior spur on the wing. However, these species appear to belong to two latitudinally differentiated faunal provinces. Species having a northern range include A. callosa, A. falciformis, and A. nanaimoensis, whereas A. phaba and A. gibbera are from more southern deposits, as are also A. halberdopsis, A. ainikta, and A. baptos.