Restudy of upper Pliocene (ca. 2.4-1.8 Ma) and possible lower Pleistocene dinoflagellates from the Royal Society borehole at Ludham, eastern England has revealed the presence of more than 29 dinoflagellate species, substantially revising earlier records of this important locality. Assemblages reflect climates that fluctuated within a warm- or mild-temperate to cool range, as shown by the discovery that specimens earlier assigned to the warm-water Tectatodinium pellitum all belong to a cool-water element comprising Bitectatodinium tepikiense, Filisphaera filifera, F. microornata, and Habibacysta tectata. This element appears to have been widely mistaken for Tectatodinium pellitum in coeval deposits of the North Sea basin and beyond. The following are among several species reported for the first time from coeval deposits of the North Sea basin: Filisphaera filifera, F. microornata, Operculodinium? eirikianum, O. giganteum, Spiniferites ludhamensis n. sp., S. rubinus, and Trinovantedinium glorianum. The dinoflagellate Spiniferites ludhamensis n. sp. and acritarch Nannobarbophora walldalei n. sp. are formally described.

A Lower Silurian (Llandovery) shelly fauna is described; the first from the Iberian Peninsula. It is dated as late Llandovery (early Telychian) by Stricklandia aff. laevis and is overlain by a late Telychian conodont fauna. The fauna is from the volcaniclastic El Castro Formation, Viodo Limestone Member, north of Viodo, Asturias, northern Spain. There are seven common and five rarer brachiopods, including the new taxa Asturorthis sarreoensis new genus and species, Mendacella cantabrica new species, Katastrophomena truyolsi new species, Viodostrophia alcaldei new genus and species, Stegerhynchus juliverti new species, and Fenestrirostra? viodoensis new species.

The fixosessile, perireefal to reefal Devonian epibiont Davidsonia cemented itself by its entire ventral valve to the underside of alveolitid tabulate corals, or to stromatoporoid sponges. It occupied a cryptic niche in perireefal biostromal thickets to reef complexes in the Old World faunal realm (Europe, western North America), and Uralian–Central Asian faunal province. A new species, D. septata, is here reported in abundance for the first time from Middle Devonian (Givetian) rocks of Yunnan, thus extending its range to South China. The usual absence of the brachial valve is suggested to be due to postmortem taphonomy as a result of its unique, cemented mode of life on the undersides of corals or sponges. A new genus of coarsely ribbed, partly libero-, partly fixosessile davidsoniid, Rugodavidsonia, type Davidsonia woodwardiana (DeKoninck), mimicking unrelated Late Paleozoic orthotetids, is also described, demonstrating that ribs evolved secondarily in a family dominated from its inception by smooth shells. Its paleogeographic distribution ranged from Europe through western North America (and possibly China), commonly accompanying Davidsonia in similar assemblages, but with a slightly different mode of life. Reexamination of available material, using thin sections, peels and SEM, confirms that the impunctate shell structure, dorsally directed spiralia, nature of the hinge mechanism, the deltidial plates, absence of a chilidium, “atrypoid” musculature and vascular markings, show features in Davidsonia and Rugodavidsonia that are all typical of the Order Atrypida. Thus, Davidsonia demonstrates that ventral valve cementation evolved independently more than once in articulate brachiopods such as strophomenids, productids, atrypids, and thecideid spiriferids. A revised classification of the Davidsonioidea and Palaferelloidea is proposed. Relationships between various genera are outlined in a new family tree for these groups. The various families discussed, including the Symmatrypidae, are united under a new suborder, the Davidsoniidina, a primarily carbonate platform and perireefal dwelling group, which first evolved during the Ludlovian (Late Silurian) in the Uralian–Central Asian tropical shelf region, diversified over a period of ~47 Ma, and then died out during the late Givetian, 10 Ma prior to the Frasnian–Famenian mass extinction events.

Hispanosinuites peeli new genus and species from the Lower Oretan shales (Middle Ordovician) of central Spain is described and placed in the new subfamily Hispanosinuitinae of the family Sinuitidae. This new subfamily is considered to represent a highly specialized phylogenetic lineage, which probably separated from the morphological range of the genus Sinuites during the Early Ordovician. The outer shell surface of Hispanosinuites peeli is entirely covered by secondary shell layers, which are interpreted as perinductura, inductura and coinductura. The similarity of these shell deposits in Hispanosinuites peeli and species of Euphemites suggests that these layers were secreted by mantle flaps having the same form in both genera. Hispanosinuites peeli is interpreted as a mobile mollusc with an internal shell adapted to an infaunal mode of life. Discovery of this unusual mollusc reopens the question of the phylogenetic relations of the families Sinuitidae and Euphemitidae, which are often assigned to different molluscan classes.

The discovery of a specimen of Nautilus praepompilius Shimansky, 1957, from the Chegan Formation of Kazakhstan confirms that this species is assignable to Nautilus, and that this extant genus extends back to the late Eocene. It is morphologically closest to Nautilus pompilius Linnaeus. The nepionic constriction shows that the hatching size was ca. 23 mm dia, close to that for Nautilus pompilius (ca. 26 mm dia).

Cyphaspis wessmani new species is a morphologically aberrant taxon from the Ludlow Henryhouse Formation of south-central Oklahoma. Its long, scoop-shaped cephalic border is without close comparison in the family Aulacopleuridae, but its possession of eleven thoracic segments with an axial spine on the sixth, an inflated glabella with tiny L1 and dorsal tuberculate sculpture, a prominently expressed bilobate eye socle, and a micropygous pygidium all support assignment to Cyphaspis. The genus is common in Silurian rocks from most parts of the world, but C. wessmani is the first published record from southern Laurentia.

Four species of carabocrinids from the Ordovician of northern Iowa and southern Minnesota are described, namely Carabocrinus radiatus E. Billings, C. vancortlandti E. Billings, C. magnificus Sardeson from the Middle Ordovician Dunleith Formation and C. slocomi Foerste from the Upper Ordovician Maquoketa Formation. Carabocrinus radiatus and C. vancortlandti are also known from the Middle Ordovician of Ontario and Quebec. In addition, C. magnificus and C. vancortlandti are recorded from the Decorah of the Twin Cities area and the Curdsville Limestone of Kentucky, respectively. Biogeographically, the Middle Ordovician carabocrinids from Iowa and Minnesota are most similar to those from rocks of similar age in the northern Appalachians.

Development of the cup and its component plates in C. slocomi is almost entirely isometric so that the its shape is largely constant regardless of size. This species exhibits ridge canals on the shoulders of the radial plates in the cup. The ridge canals probably served for respiration. As expected, the number of ridge canals and their length increase with positive allometry compared to the size and volume of the cup. Growth of the ridge canals restricts the width of the radial facets.

The extant irregular echinoids Echinoneus cyclostomus Leske and Brissus unicolor (Leske) are reported from the middle Pleistocene of Barbados. The moderately robust E. cyclostomus is well-preserved, while B. unicolor, which had a thin test in life, occurs as an internal mold. The holectypoid E. cyclostomus sensu lato occurs in fossiliferous deposits of Upper Oligocene to Pleistocene age in the Antillean region, showing remarkably little overall variation in test shape during this period. Similarly, gross morphological features of Recent B. unicolor are not dissimilar to those seen in some Caribbean species from the Paleogene, such as B. sp. cf. B. unicolor from the Middle Eocene of Jamaica. Superior fossil specimens will be required to determine if certain fossil species within these genera are valid. This analysis supports the observation that many taxa of the modern Antillean, shallow-water echinoid fauna have essentially persisted within the region since at least the Oligocene.

New data on the proximal structure of several glossograptid species, including Paraglossograptus holmi, indicate that symmetry between sicula and the first theca is ubiquitous and primitive for the group. This isograptid symmetry is shared with species of Isograptus and Oncograptus, among others, as is a dicalycal second theca, and the initial downward growth of the first several thecal pairs. Consideration of these and other features of the rhabdosome structure leads us to reassess the phylogenetic relations among Glossograptus, Pseudisograptus, Isograptus, and their relatives. The Glossograptidae is a holophyletic clade comprising the common ancestor of Isograptus caduceus and I. victoriae and all its descendants, including the monopleural glossograptines. Incipient monopleural development is exhibited by the otherwise Isograptus-like Bergstroemograptus crawfordi. Derived glossograptids, such as Glossograptus and Kalpinograptus, share a fully monopleural rhabdosome with a prominent proximal bulge formed by the overlap of the early thecae. Contrary to some claims, none possesses a manubrium or manubrium-like structure. The manubrium and the arienigraptid suture are restricted to Arienigraptus hastatus and its descendants. These features unite the Arienigraptidae. The Arienigraptidae, based on their possession of isograptid symmetry and lack of any derived characters shared uniquely with the glossograptids, appear to be a sister group of the Glossograptidae rather than a stem group. These two families appear most closely allied to certain reclined, two-stiped species, such as Isograptus? dilemma, that retain tetragraptid proximal symmetry.

Tremadocian onlap is recorded by the Tribes Hill Formation. The formation is a lower Lower Ordovician (upper conodont Fauna B Interval(?)-Rossodus manitouensis Zone) depositional sequence that unconformably overlies the Upper Cambrian Little Falls Formation.

Depositional environments and stratigraphy indicate that the Tribes Hill was deposited on a wave-, not tide-, dominated shelf and that a uniform, “layer-cake” stratigraphy is present. The deepening-shoaling sequence of the Tribes Hill includes the: 1) Sprakers Member (new; peritidal carbonate and overlying tempestite limestone and shale); 2) Van Wie Member (new; subtidal shale and limestone); 3) Wolf Hollow Member (revised; massive carbonates with thrombolitic cap); and 4) Canyon Road Member (new; glauconitic limestone and overlying evaporitic dolostone). The shoaling half-cycle of the Tribes Hill is older than a shoaling event in western Newfoundland, and suggests epeirogenic factors in earliest Ordovician sea-level change in east Laurentia. Conodont and trilobite biofacies track lithofacies, and Rossodus manitouensis Zone conodonts and Bellefontia Biofacies trilobites appear in the distal, middle Tribes Hill Formation.

Twenty-four conodont species are illustrated. Ansella? protoserrata new species, Iapetognathus sprakersi new species, Leukorhinion ambonodes new genus and species, and Laurentoscandodus new genus are described.

The Giant Rat Kangaroos (Ekaltadeta, Propleopus) were placed in a new subfamily the Propleopinae by Archer and Flannery (1985). The discovery of new Ekaltadeta material from Riversleigh, northwestern Queensland has stimulated a review of propleopine phylogeny. Cladistic analysis of five propleopine taxa suggests possible paraphyly for Ekaltadeta and polyphyly for Propleopus. A new species of Miocene propleopine, Ekaltadeta jamiemulvaneyi n. sp., from system C local faunas at Riversleigh, is described.

Five taxa of amynodontid rhinoceroses have been named from Kazakhstan. We consider only two of these valid, and recognize three amynodontid taxa from Paleogene deposits in Kazakhstan: Cadurcodon ardynensis (=Cadurcodon zaisanensis; =Amynodon tuskabakensis) from the upper Eocene (Ergilian)-lower Oligocene (Shandgolian) of the Zaysan basin, Zaisanamynodon borisovi, from the Ergilian of the Zaysan basin and Cadurcodon kazakademius, from Shandgolian strata in the vicinity of the Chelkar-Teniz lake basin. Gigantamynodon akespensis, from the upper Oligocene north of the Aral Sea is a rhinocerotid, not an amynodontid. Close similarity of the amynodontids of Kazakhstan to those of Mongolia and China supports direct correlation of Ergilian and Shandgolian strata across Asia.

Small bioherms in the uppermost Tansill Formation and Capitan Limestone in the northern Guadalupe Mountains, New Mexico, have been informally interpreted as sponge reefs by past workers. Samples collected during the present cycle of field work in 1993 and 1994 suggest that some of these isolated carbonate mounds have a different origin. Guadalupe Mountains complexes have been recognized for many years as outstanding models for interpretation of reefs, reef facies, and reef faunas (for example, King, 1948; Newell et al., 1953; Achauer, 1969; Yurewicz, 1976, 1977; Babcock, 1977; Kirkland et al. 1993).