Ordovician material from the Platteville Formation (Sandbian) of southern Wisconsin and Big Hill Formation (Katian) of northern Michigan is described that provides novel information about the phylogenetic affinity, taxonomic diversity, and stratigraphic range of the nonbiomineralized taxa Buthograptus, Callithamnopsis, and Chaetocladus. Two new species of Buthograptus, a previously monotypic genus, are erected on the basis of the Platteville Formation material, Buthograptus gundersoni n. sp. and B. meyeri n. sp., and new occurrences of B. laxus are recorded from several localities and two distinct stratigraphic levels within this unit. On the basis of scanning electron microscopic investigation of the material and the fact that each of the three Buthograptus species has a close counterpart in the frond morphology of an extant species of Caulerpa, Buthograptus is interpreted as a member of the green algal order Bryopsidales. New specimens from the Platteville Formation assigned to Callithamnopsis reveal new morphological details for the type species, C. fruticosa (Hall, 1865), aspects of which indicate that the genus belongs to the family Triploporellaceae rather than Seletonellaceae within the green algal order Dasycladales, and Chaetocladus material from the Big Hill Formation includes specimens that are formally assigned to Chaetocladus dubius (Spencer, 1884), a species of dasycladalean alga known previously only from the mid-Silurian of Ontario.

Based on multivariate morphometric analysis, Halysites catenularius is identified from the Rumba Formation (Telychian) and Jaagarahu Formation (Sheinwoodian) of Estonia; H. priscus is confirmed as a junior synonym. Halysites catenularius, H. junior, and H. senior are shown to be closely related; H. catenularius is morphologically intermediate. Cyclomorphism in H. catenularius, recorded by fluctuations of corallite tabularial area, indicates an average annual growth rate of 6.0 mm, which is typical for halysitids. Tubules in H. catenularius, generated from small intramural openings between adjacent corallites, were involved in two types of interstitial increase. The intramural openings, three types of lateral increase, temporary agglutinated patches of corallites, and axial increase documented in H. catenularius resemble features in some species of Catenipora. These similarities are consistent with the interpretation that Halysites evolved from Catenipora. Evaluation of the possibility that both genera are polyphyletic will require further detailed analysis of additional species.

Lower to probably Middle Devonian bryozoans from western Argentina are reported. Five genera of trepostomes: Leptotrypa, Leptotrypella, Eridotrypella, Cyphotrypa, Boardmanella, and the cryptostome ?Pseudonematopora are described and figured. The paleobiogeographical significance of these bryozoans was analyzed in the context of Southern Gondwana during the Devonian. The group was considered as nearly absent from southwestern marine basins. In contrast with highly endemic groups, supporting the recognition of the Malvinokaffric Realm in this region, bryozoans reported are nearly cosmopolitan. The presence of those genera typical of warm-temperate, carbonate settings from low paleolatitudes, such as the Laurentian-European Eridotrypella, Leptotrypa, and Leptotrypella, or the Eurasians Boardmanella and ?Pseudonematopora, implies that these taxa were euritopic with remarkable capabilities for dispersion to reach high-latitude siliciclastic environments of the Southwestern Gondwanan basins.

The Glen Rose and Walnut formations of southcentral and northcentral Texas comprise shallow-water carbonates deposited during the late Aptian to middle Albian on a carbonate platform. The formations are famous for their rich fossil faunas. Although bryozoans are absent in late Aptian sediments, they are frequently found encrusting bivalve shells from the early to middle Albian parts of these formations. Here, we describe the cyclostome bryozoan fauna, which includes six species; Stomatopora sp., Oncousoecia khirar n. sp., Reptomultisparsa mclemoreae n. sp., Hyporosopora keera n. sp., Mesonopora bernardwalteri n. sp., and ?Unicavea sp. Most cyclostomes are found encrusting rudist shells from Unit 2 of the Lower Member of the Glen Rose Formation and units 3 and 6 of the Upper Member of the Glen Rose Formation.

Gymnolaemate bryozoans are common encrusters on bivalve shells from the early to middle Albian parts of the Glen Rose and Walnut formations of southcentral and northcentral Texas. Here, we report for the first time the presence of seven gymnolaemate bryozoans, all of which represent new species. They include the bioimmured ctenostome Simplicidium jontoddi n. sp., and the cheilostomes Rhammatopora glenrosa n. sp., Iyarispora ikaanakiteeh n. gen. n. sp., Iyarispora chiass n. gen. n. sp., Charixa bispinata n. sp., Charixa sexspinata n. sp., and Charixa emanuelae n. sp. The Glen Rose bryozoans slightly antedate the commencement of an explosive bryozoan radiation and the first appearance of neocheilostomes in the late Albian. Although the diversity of cheilostomes in the Glen Rose and Walnut formations is similar to that of cyclostomes, cheilostomes are more abundant and produced larger colonies. These formations therefore yield the oldest known bryozoan assemblage dominated in terms of biomass by cheilostomes. The genus concept of Charixa is discussed and amended.

In midcontinent North America, the Fox Hills Formation (Upper Cretaceous, upper Maastrichtian) preserves the last marine faunas in the central Western Interior Seaway (WIS). Neritoptyx hogansoni new species, a small littoral snail, exhibited allometric change from smooth to corded ornament and rounded to shouldered shape during growth. Specimens preserve a zig-zag pigment pattern that changes to an axial pattern during growth. Neritoptyx hogansoni new species was preyed on by decapod crustaceans, and spent shells were occupied by pagurid crabs. Dead mollusk shells, particularly those of Crassostrea subtrigonalis (Evans and Shumard, 1857), provided a hard substrate to which they adhered on the Fox Hills tidal flats. This new neritimorph gastropod establishes a paleogeographic and chronostratigraphic proxy for intertidal conditions on the Dakota Isthmus during the lateMaastrichtian. Presence of a neritid extends the marine tropical/temperate boundary in the WIS northward to ∼44° late Maastrichtian paleolatitude. Late Maastrichtian closure of the isthmus subsequently altered marine heat transfer by interrupting northward flow of tropical currents from the Gulf Coast by as much as 1 to 1.5 million years before the Cretaceous ended.

Hippuritids, particularly those with multiple-folds, are one of the most characteristic components in uppermost Cretaceous rudist-bearing strata of the Caribbean Province. The hippuritid rudist fauna of the Chiapas Central Depression includes the following taxa: Vaccinites vermunti Mac Gillavry, 1937 and Barrettia cf. B. ruseae Chubb, 1967 from the early Campanian Suchiapa Formation; B. monilifera Woodward, 1862, B. gigas Chubb, 1955, and Parastroma trechmanni Chubb, 1967 from the mid Campanian Suchiapa Formation; and Praebarrettia sparcilirata (Whitfield, 1897) from the early Maastrichtian Ocozocoautla Formation. These six species are described herein in detail. New observations on the outer shell layer structure of the right valve and the pore-canal system of the left valve led to amending the diagnoses of the g|enera Barrettia Woodward, 1862, Parastroma Douvillé, 1926, and Praebarrettia Trechmann, 1924. Also, the revision of Chiapas' and other American species of multiple-fold hippuritids led to proposed changes in their generic adscription.

Zygochlamys Ihering, 1907 is revised and three new genera of tribe Chlamydini are named: the monospecific early Miocene genera Pixiechlamys new genus (type species: Pecten quemadensis Ihering, 1897) and Chokekenia n. gen. (type species: Zygochlamys nicolasi Morra, 1985), and the late Miocene–early Pliocene Moirechlamys n. gen., containing Pecten actinodes Sowerby, 1846 (type species) and Chlamys auroraeFeruglio, 1954. Zygochlamys is restricted to include Z. geminata (Sowerby, 1846) (type species), Z. jorgensisIhering, 1907, and Z. sebastianiMorra, 1985. The present analysis increases the biostratigraphic usefulness of the group and improves taxonomic knowledge of the Neogene molluscan assemblages defined previously for Patagonia. Zygochlamys geminata is confined to the latest Oligocene–early Miocene interval of the Austral Basin of Patagonia (Argentina) and to the early Miocene of Chile, Z. jorgensis is restricted to the early to middle Miocene of the Golfo San Jorge and northern Austral Basins, and Moirechlamys n. gen., the most widespread genus, occurs in the late Miocene–early Pliocene of the Austral, Golfo San Jorge, Valdés, and Colorado basins. All these genera are endemic to southern South America; Zygochlamys is not related to other circumpolar genera such as AustrochlamysJonkers, 2003 or PsychrochlamysJonkers, 2003, rejecting its dispersal in the Antarctic Circumpolar Current, as has been proposed previously.

A nepticulid leaf-mine ichnofossil, Stigmellites janggi Sohn and Nam, n. ichnosp., is described on the basis of a fossil leaf of Fagus from the early Miocene Geumgwangdong Formation in Pohang Basin. This mine trace is characterized by a linear-blotch type with a clear centric frass trail composed of closely and randomly dispersed pellets filling the mine width in the early stage. We found traces of a possible egg case and an exit slit from the leaf. These features are most consistent with those produced by members of Nepticulidae. Our record demonstrates for the first time the trophic association of Nepticulidae with Fagus in the Miocene and suggests the persistence of a long-term association between the insect family and the plant genus from the Miocene to the present. Other Nepticulidae leaf mines in the Miocene and leaf-mine fossils from the Geumgwangdong Formation are briefly reviewed.

We describe a partial dyrosaurid skeleton recently prepared out of a limestone block discovered in the 1930s from Danian strata along the Atlantic coast of Senegal. The specimen, from a single individual, comprises nicely preserved elements of the appendicular and axial skeleton from the abdominal and sacral region, which enables us to refine our knowledge on some postcranial characteristics of the Dyrosauridae. Although Dyrosauridae are abundant in early Eocene deposits of North Africa, the present discovery in the Danian of Senegal fills a patchier record early after the K/Pg boundary and provides an important comparative data point with the few other Danian dyrosaurid records such as Atlantosuchus from nearby Morocco or Guarinisuchus and Hyposaurus from Brazil and the USA, respectively.

We revisit the holotype of Calcardea junneiGingerich, 1987 from the latest Paleocene (Clarkforkian) of the Willwood Formation (Wyoming, USA). The species is based on a partial skeleton and was originally assigned to the Ardeidae (herons). As we show, this classification cannot be upheld and CalcardeaGingerich, 1987 more closely resembles the taxon VastanavisMayr et al., 2007 (Vastanavidae), a parrot-like bird from the early Eocene of India. Even though C. junnei is a large bird, its long wings and short tarsometatarsus argue against a predominantly terrestrial way of living, and the morphology of the tarsometatarsus and pedal phalanges instead suggest strong grasping feet. We conclude that an assignment of Calcardea to the landbird clade (Telluraves) is better supported than its classification into the waterbird clade (Aequornithes), which includes Ardeidae and other ‘ciconiiform’ and ‘pelecaniform’ taxa. Calcardea junnei is one of the oldest known representatives of Telluraves and its morphology shows plesiomorphic features, which contributed to its previous misidentification as a heron. Calcardea exhibits a distinctive osteology and affords a glimpse of a previously unknown late Paleocene avian morphotype.

New fossil material of Auliscomys formosusReig 1978 allows restudy of the oldest known South American representative of the subfamily Sigmodontinae. Description of Auliscomys formosus was based on a fragmentary dentary exhumed from the Monte Hermoso Formation of central Argentina. Previous studies allocated A. formosus to the early Pliocene. A reevaluation of dental and cranial morphology, including for the first time the upper dentition, and the inclusion of A. formosus in a phylogenetic analysis of the tribe Phyllotini indicate that A. formosus represents a new genus, Kraglievichimys. Kraglievichimys shares a mosaic of characters with the living Auliscomys Osgood, 1915 and LoxodontomysOsgood, 1947. The taxonomic reassignment of A. formosus and the possibility that the Monte Hermoso Formation may be younger than early Pliocene in age provide a new understanding of cricetid diversification in South America. Estimates of sigmodontine ancestry by molecular approaches are biased toward older ages, whereas this new interpretation of the history of K. formosus suggests that the South American history of sigmodontines spans less than 4 million years.

Living Caprini are dominant bovids in the pan-Tibetan area that are strongly adapted to dry steppe and high-mountain meadow habitats. Some taxa with Holarctic distributions, e.g., Ovis Linnaeus, 1758, were thought to originate on the Tibetan Plateau and subsequently dispersed elsewhere, which was depicted as an ‘out of Tibet’ story. However, except for some information on a stem caprine assemblage from the Qaidam Basin, the early evolution of Caprini around the Tibetan Plateau is poorly known. Here, we report new material of Olonbulukia tsaidamensis Bohlin, 1937, which was a member of this stem caprine assemblage, from the Wuzhong region, northern China, confirming the similarity of the Wuzhong Fauna and ‘Qaidam Fauna.’ Based on a biometric study of horncores from the ‘Qaidam’ and Wuzhong faunas, we recognize six taxa from this stem caprine assemblage: O. tsaidamensis, O. sp., Qurliqnoria cheni Bohlin, 1937, Tossunnoria pseudibex Bohlin, 1937, ?Protoryx cf. P. enanus Köhler, 1987, and cf. Pachytragus sp. Among these taxa, Q. cheni and T. pseudibex are probably related to some extant Tibetan endemic species, e.g., the Tibetan antelope, Pantholops hodgsonii (Abel, 1826), and the Himalayan tahr, Hemitragus jemlahicus (Smith, 1826). Others might be ancestral to the Turolian caprine assemblages and even possibly gave rise to the extant Caprina. This work reveals an early radiation of stem caprines along the northern side of the rising Tibetan Plateau and indicates a mixed pattern of pan-Tibetan stem caprine evolution prior to their dispersal out of the Tibetan Plateau.