New specimens of Gabelia pedunculus Rigby and Murphy, 1983, and of the new species Gabelia giganta and Gabelia fascicula are described from the Siluro-Devonian(?) Roberts Mountains Formation from Loomis Creek Canyon in the Snake Mountains, northeastern Elko County, Nevada. Stalk fragments of G. pedunculus are similar to the holotype from the northern Roberts Mountains, Eureka County, Nevada. Gabelia giganta n. sp. is a large species with skeletal elements in the stalk twice the size of elements in G. pedunculus. Gabelia fascicula n. sp. is based on thick-walled, cup-like upper parts where a gastral layer of coarse, diagonally oriented spicules contrasts to a dermal layer of regular vertical and horizontal bundles of hexactine-based spicules of at least two orders around parietal gaps. The specimens are all part of a probably transported seafloor assemblage.

The uppermost Lower Silurian and Upper Silurian Gascons and West Point Formations of the southern Gaspé Peninsula were deposited under a broad range of environmental conditions from deep offshore-shelf to reef facies. Halysitid and auloporid tabulate corals occur in a number of facies and show a high degree of endemism.

Two species of Halysitidae and three species of Auloporida are found in these formations. Both halysitids have been previously described from this region. The auloporids include the new species Syringopora minuta and another species that may represent the first known Silurian occurrence of the fletcheriellid genus Pseudofletcheria. A neotype for the halysitid Cystihalysites amplitubulatus (Lambe) is proposed.

Rugose and tabulate corals from the Lower Permian (Wolfcampian, Leonardian) Bird Spring Group in the Lee Canyon section of the Spring Mountains, Clark County, Nevada, are referred to eight genera and ten species. New taxa are Fomichevella nevadensis n. sp., F. waltersi n. sp., Mccloudius parvus n. sp., and Paraheritschioides richi n. sp. The fauna is most similar to the shelf fauna in eastern Nevada, but there are significant similarities to corals from the Antler Highland embayments of central Nevada and southern Idaho and to faunas of the same age in northern California and northern British Columbia. The paleogeography is interpreted as shallow water near the east side of the mouth of a south-opening coastal sea, bordered on the east by the continent and on the west by the Antler Highland. Corals migrated south along the western shores of the Antler Highland and mixed with the shelf fauna, perhaps with some corals crossing from Tethys to the coast. The modern eastern Pacific tropical coral faunas, which have several hermatypic coral genera and species derived from the western Pacific in the Pleistocene, may occupy a somewhat similar geography near the mouth of the modern Gulf of California.

Cocks and Rong (1989) subdivided the species of the Ordovician brachiopod genus Bimuria into two groups, those with a simple, or not undercut, cardinal process and those with an undercut cardinal process. They placed the second group in a new genus, Cooperea, and grouped Cooperea with Craspedelia in the new subfamily Craspedeliinae of the family Sowerbyellidae. However, the cardinal process of Bimuria ranges from not undercut to undercut within at least two species. Cooperea is therefore placed in synonymy with Bimuria, and Craspedelia is returned to the Bimuriidae.

Cocks and Rong (1989) inferred that, with rare exceptions, the cardinal process of the Plectambonitacea evolved from simple to trifid to undercut. The evidence from Bimuria indicates, however, that the undercut process developed more than once and, in Bimuria, directly from the simple type.

As an adjunct to the above discussion three new species are described: Bimuria gilbertella, Craspedelia intonsa, and Craspedelia sp. 1. Craspedelia is a rarely reported genus documented here for the first time in western North America (northern California). Additional evidence is introduced that the ratio Lmusbv/Lebv decreased from middle to late Ordovician species of Bimuria.

Chama iudicai n. sp. is described from the Pleistocene of San Antonio Oeste, Rio Negro Province, Argentina. It is characterized by its large size, thick shell, and crenulated inner margin. Externally it has weak comarginal lamellae. It is indicative of a clear, stenohaline, warm-water environment. This is the first record for the family Chamidae in the Argentine Quaternary.

Large collections of Glyptopleura costata (McCoy, 1844) from the Maxville Limestone in central Ohio contain four instars and adults. The juveniles provide a basis for understanding the orderly development of the complex ornamentation of costae characteristic of Glyptopleura. Dimorphism is prominent with heteromorphs and adult tecnomorphs readily identifiable, primarily in adults. Progressive development of the ornamentation in juveniles, significant variation in adult ornamentation, and dimorphism has led to a proliferation of proposed taxa.

On the western side of the Tjörnes Peninsula in northern Iceland exposures of fossiliferous marine sediments, basalts, and glacial tills record the climatic history of this region of the North Atlantic Ocean. Seventy-five marine ostracode species were recovered from the Pliocene Tjörnes sediments and Quaternary sediments known as the Breidavik beds. The ostracode assemblages contain many warm-water genera that do not inhabit Iceland today and indicate early to middle Pliocene (4.5–3.0 Ma) winter and summer bottom-water temperatures that averaged 5–6°C and 14–16°C, respectively (maximum 20°C in summer, rarely below 3°C in winter except during a brief cooling 3.5–3.2 Ma). An intensified North Atlantic Drift and a diminished or absent East Greenland Current account for warm-water oceanographic conditions at 66°N. Late Pliocene marine climates were cooler with winter and summer averages of about 9°C and 8°C. Early Pleistocene ostracode assemblages dated at 1.7–1.3 Ma contain extant arctic–subarctic species that indicate winter and summer temperatures of about − 1.5°C and 4–5°C. New species Bensonocythere eirikssoni, Robertsonites williamsi, Hemicythere rekaensis, Thaerocythere mayburyae, Thaerocythere whatleyi, Leptocythere tjornesensis, Tetracytherura bardarsoni, and Cytheromorpha einarssoni are described.

The discovery of beautifully preserved specimens of a macruran decapod provides the basis for redescription of Hoploparia antarctica Wilckens, a hitherto poorly known species from the Campanian–Maastrichtian of the Austral basin of Southern Patagonia. Analyses of the associated molluscan fauna, trace fossils, and sedimentary structures indicate that the material is mostly preserved in calcareous sandstones and coquinas deposited in shallow, well-oxygenated environments. These new findings of H. antarctica in Maastrichtian deposits of the Lefipán Formation of Chubut expand the geographic distribution of the species and add a new element for the comparison of the Lefipán fauna with that of the austral Wedellian Province.

In the South Nahanni River area of the District of Mackenzie, the Middle Ordovician Sunblood Formation comprises mainly limestones and dolostones of intertidal and shallow-subtidal origin, as indicated by the presence of desiccation polygons, fenestral fabric, and oncolites. Faunas of well-preserved, silicified trilobites from a low-diversity, nearshore, Bathyurus-dominated biofacies are compositionally distinct from faunas in correlative strata around North America that represent different shelf to upperslope biofacies. A temporal biostratigraphy applicable to nearshore biofacies through much of the Whiterockian Series consists of five zones, in ascending order: Bathyurus mackenziensis, B. sunbloodensis, B. margareti, B. nevadensis, and B. granulosus. Twenty-six species are assigned to 18 genera, of which Ludvigsenella is new. Three new species of Bathyurus are B. mackenziensis, B. sunbloodensis, and B. margareti.

Phylogenetic parsimony analysis forms a basis for classification of the Siegenian–Eifelian “Malvinella group,” a monophyletic taxon within the “Metacryphaeus group” of the family Calmoniidae. Fifty-one exoskeletal characters for Metacryphaeus Reed and 12 taxa of the “Malvinella group” yield a shortest length cladogram with a consistency index of 0.51. A classification based on retrieving the structure of this cladogram recognizes six genera: Malvinella Wolfart, Vogesina Wolfart, Palpebrops n. gen. (type P. donegalensis n. sp.), the sister taxa Parabouleia Eldredge and Bouleia Kozlowski, and Plesiomalvinella n. gen. [type P. pujravii (Wolfart)]. Palpebrops is more closely related to Vogesina than to Malvinella; Amazonian species are nested within this group as sister taxa to Andean or Amazon/Andean clades. Bolivian Belén Formation Malvinella buddeae n. sp. is an allopatric species distinct from Icla Formation M. haugi (Kozlowski). “Metacryphaeus” of recent revisions is a paraphyletic grade group including primitive species of the “Malvinella group.” Metacryphaeus australis (Clarke), M. tuberculatus (Kozlowski), and M. caffer (Salter) are endemic to the Paraná Basin, Andean Bolivia–Parnaíba Basin, and South Africa, respectively.

Abundant, well-preserved specimens of a new peltocystidan mitrate carpoid, Jaekelocarpus oklahomensis n. gen. and sp., have been discovered in the Pennsylvanian (Morrowan Series) Gene Autry Shale Member, Golf Course Formation, in southern Oklahoma. The new carpoid postdates the youngest previously known carpoids (Middle Devonian) by about 65 million years. It is characterized by a small (to 4 mm in length) globose theca composed of six plates: two large adaulacophorals, two large marginals, and two relatively small plates that frame the main thecal orifice. One of the plates at the orifice bears a single stout spine. The theca and plates that comprise the theca display a high degree of bilateral symmetry. In contrast, the styloid has an asymmetrical array of spines and blades.

We hypothesize that most mitrates, including this one, were adapted to an infaunal life mode. The streamlined, generally symmetrical body shape is an adaptation to moving on or through the substrate. Spines and blades on the lower surface of the styloid and proximal aulacophore are inferred to be adaptations for gripping the substrate as the animal pulled itself backwards (aulacophore first). The main thecal orifice opposite the aulacophore was the site of both mouth and anus. Evidence for a sluggish, epifaunal life mode in the cornute carpoids includes the typically flattened, asymmetrical body, the presence of downward projecting spines and knobs on the marginal thecal plates of many species, and the specialized thecal pores and slits that faced away from the substrate.

Uppermost Cambrian and lowest Ordovician slope deposits in Highgate Gorge, northwestern Vermont, yield a succession of conodont faunas (and a few associated trilobite species) similar to that observed in coeval North American carbonate-platform sequences. Decimeter-scale sampling of a 15-m-interval in two sections comprising thin-bedded limestone–shale rhythmites alternating with thick-bedded debris flow conglomerates yielded 60 trilobite specimens and more than 5,000 conodont elements from 48 productive horizons. The new biostratigraphic control does not support earlier claims that the lowest occurrence of Cordylodus proavus in the Gorge Formation and presumably in other slope sequences is significantly older than the base of the C. proavus Zone in platform deposits; rather, it demonstrates the isochronous persistence of this boundary across the North American (Laurentian) shelf margin into Iapetan slope deposits. The common occurrence of the deep, cool-water conodont Eoconodontus alisonae and the agnostoid trilobite Lotagnostus hedini in the Eoconodontus Zone at Highgate Gorge makes it possible to extend the correlation even farther from the Laurentian platform into uppermost Cambrian strata in Kazakhstan and China. This new information greatly strengthens arguments in favor of using this zonal boundary for defining the international boundary between the Cambrian and Ordovician Systems.

In earlier studies of Highgate Gorge strata, composite treatment of biostratigraphic data from similar but non-correlative intervals (Zones 2 and 3) in two sections created an illusion of significant stratigraphic overlap of C. proavus with older faunas and direct association of some trilobite species for which overlap has never been established. Composite treatment of data from Zones 2 and 3 under designations such as “main zone’ or “upper zone’ should be discontinued and species that have been reported as occurring together in the “main zone’ should not be assumed (on the basis of that association alone) to have come from the same stratigraphic level.

The Bridgeboro Limestone, a rhodolith- and coral-bearing limestone in southwestern Georgia, has been assigned to the Vicksburgian Stage (Lower Oligocene) of the Gulf Coast based on the occurrence of the bivalves Chlamys (Anatipopecten) anatipes (Morton) and C. (Lyropecten) duncanensis Mansfield. This assignment is further substantiated by the recent recognition of the distinctive bryozoan Tubucellaria vicksburgica Canu and Bassler. The Bridgeboro also contains the larger foraminifera Lepidocyclina (Lepidocyclina) mantelli (Morton), L. (Nephrolepidina) yurnagunensis Cushman, and L. (Eulepidina) undosa Cushman, an assemblage indicative of the Lepidocylina (s.s.) subzone of the Eulepidina Zone of Early Oligocene age. These foraminifera are also characteristic of the Duncan Church beds of the Florida panhandle, and an assemblage of isolepidine and eulepidine Lepidocyclina also occurs in the Glendon Limestone of Alabama. On the basis of larger foraminifera, macroin vertebrates, and physical stratigraphic relationships, we propose that the Bridgeboro, Duncan Church, and Glendon are biostratigraphically and lithostratigraphically correlative. The Glendon Limestone has been previously assigned to nannoplankton zone NP22, and also occurs within the Cassigerinella chipolensis–Pseudohastigerina micra planktonic foraminiferal zone, both of Early Oligocene age. Based on correlation with the Glendon, the age of the Bridgeboro is thus Early Oligocene (Rupelian), middle Vicksburgian.

Calcareous algae are frequent constituents in the shallow-marine limestone intercalations of late Aptian–Maastrichtian strata of the Eastern Desert of Egypt, the Sinai, and southern Jordan. A total of 18 species of green algae (among them 16 dasycladaceans with Praturlonella hammudai n. comb. and Praturlonella jordanica n. sp., two udoteaceans) and eight species of red algae (among them two gymnocodiaceans, three solenoporaceans, and one squamariacean) are described and compared with algae from several Tethyan occurrences. The stratigraphic distribution is calibrated by 10 assemblage-zones based on the associated foraminiferids and compared with 10 ammonite assemblage-zones.

The algal contents vary within the different strata: their total contents and diversities increase from the late Aptian–Albian carbonates to the Cenomanian and decrease to the Turonian–Coniacian; no algae were proved in the Santonian–Campanian. The Maastrichtian occurrences are limited to one outcrop.

Direct physical evidence for predation upon decapod crustaceans is extremely limited in the fossil record. Although it is well recognized that decapods serve as a food resource for a wide variety of vertebrate and invertebrate predators and that the remains of decapods, in the forms of molts and corpses, are readily scavenged, direct evidence for these activities is limited (Tshudy et al., 1989). Bishop (1975) summarized evidences for predation in the fossil record and, although he frequently referred to decapods as predators, cited only one example (Bishop, 1972) of the group as prey. Thus, the discovery of three specimens of freshwater decapods, referable to the crayfish family Cambaridae, that clearly exhibit the effects of predation is significant.