The late Miocene (11.5–5.5 million years ago) was a period of faunal change for small mammal communities. The evolution of several climatic parameters has greatly impacted faunas from Europe, and the surviving species also had to deal with the competitive pressure of new migrant species into Europe. In this context, mammal groups having high sensitivity to climatic parameters, such as temperature and humidity, show peculiar patterns of evolution. This is the case for the Erinaceidae (hedgehogs and gymnures) and the extinct family Dimylidae, well recorded in the fauna from the late Miocene of Slovakia. At least six Erinaceidae and two Dimylidae were present in Slovakia during that time, as shown by material extracted from the localities of Borský Svätý Jur, Krásno, Pezinok, Šalgovce, Studienka, and Triblavina. Both families were extremely abundant during the early part of the late Miocene, the Vallesian (11.5–9.0 million years ago), supporting the idea that central Europe played an important role in the preservation of high paleodiversity of insectivore species. However, the abundance of the Erinaceidae and Dimylidae strongly declined afterward, eventually leading to the extinction of the Dimylidae soon after the Vallesian. On a smaller scale, the material described from the late Miocene of Slovakia brings a lot of new information about the morphology, variability, and phylogeny of the identified species, namely ‘Schizogalerix’ voesendorfensis, Schizogalerix cf. S. moedlingensis, Lantanotherium sanmigueli, Atelerix cf. A. depereti, Atelerix aff. A. depereti, cf. Postpalerinaceus sp. indet., Erinaceinae gen. indet. sp. indet., Plesiodimylus chantrei, and Metacordylodon aff. M. schlosseri.

The families Erinaceidae and Dimylidae are represented in the late Miocene localities of Slovakia (Borský Svätý Jur, Krásno, Pezinok, Šalgovce, Studienka, and Triblavina) by at least six hedgehog species—‘Schizogalerix’ voesendorfensis (Rabeder, 1973); Schizogalerix cf. S. moedlingensis (Rabeder, 1973); Lantanotherium sanmigueli Villalta and Crusafont, 1944; Atelerix cf. A. depereti Mein and Ginsburg, 2002; Atelerix aff. A. depereti, cf. Postpalerinaceus sp. indet., and Erinaceinae gen. indet. sp. indet.—and two dimylid species—Plesiodimylus chantrei Gaillard, 1897; and Metacordylodon aff. M. schlosseri (Andreae, 1904). Material of L. sanmigueli from the western Carpathians was investigated, revealing broad variability in all samples. Additionally, the deciduous premolars of Lantanotherium Filhol, 1888 are described here for the first time. Erinaceid species are frequent in the Vallesian but their abundance strongly declined afterward. As an exception, Schizogalerix Engesser, 1980 re-entered the Danube and Vienna basins during MN11, likely from eastern Europe. Members of Erinaceinae display low diversity during the late Miocene of central Europe, which tends to support a pan-European diversity phenomenon. The humidity-dependent Dimylidae spp. were abundant during the late Vallesian. Rare finds of Plesiodimylus Gaillard, 1897 confirm the survival of this family into the early MN11 in the Pannonian region.

An unusual worm, previously interpreted as the earliest leech, is described from 437 year old marine strata of Wisconsin. Lacking preserved internal organs, it is ∼16 cm long, 8.2 mm wide, with 250 annulations and a circular structure at one end, which the authors interpret as the broken end of a molt. It is therefore referred to the Cycloneuralia, a group of worms that shed their skin.

An unusual worm, previously interpreted as the earliest leech, is described from the early Silurian (Llandovery, Telychian) Brandon Bridge Formation Lagerstätte (Waukesha Biota) of Wisconsin (∼437 Ma). Lacking preserved internal organs, it is up to ∼16 cm long, 8.2 mm wide, with ∼250 annulations and a circular structure at one end, interpreted here as the broken end of a molt. It is therefore referred to Cycloneuralia incertae sedis.

The new coral species Streptelasma rutkae and a cephalopod belonging to the genus Gorbyoceras occur in nearshore shallow-marine sandstone of the Whirlpool Formation in Hamilton, southern Ontario. They are the first macrofossils contributing to a modern understanding of the geologic age and correlation of this formation. Streptelasma rutkae most closely resembles a species that occurs widely in the Edgewood Biogeographic Province of the east-central United States, in rocks dating to the latest part of the Ordovician Period. Gorbyoceras is present in Late Ordovician rocks in the Cincinnati Arch region. Thus, the occurrences of Streptelasma rutkae and Gorbyoceras support other fossil and chemical data suggesting that the age of the Whirlpool Formation is latest Ordovician, rather than earliest Silurian as traditionally thought. They also indicate paleogeographic connections between the area where the Whirlpool Formation was deposited in Ontario and the Edgewood Biogeographic Province and Cincinnati Arch region in the east-central United States.

Solitary rugose corals assigned to Streptelasma rutkae n. sp. and an annulated orthoconic cephalopod identified as Gorbyoceras sp. occur in nearshore shallow-marine sandstone of the Whirlpool Formation in Hamilton, southern Ontario. They are the first macrofossils contributing to a modern understanding of the age and correlation of this stratigraphic unit. Streptelasma rutkae most closely resembles S. subregulare (Savage, 1913), which occurs widely in the Edgewood Province of the east-central United States, in strata considered latest Ordovician (Hirnantian). Gorbyoceras ranges into the latest Katian (latest Richmondian) in the Cincinnati Arch region. Thus, the occurrences of S. rutkae and Gorbyoceras sp. support other biostratigraphic and chemostratigraphic data suggesting that the Whirlpool Formation is latest Ordovician, rather than earliest Silurian as traditionally thought. They also indicate paleogeographic connections between the area of Whirlpool deposition in Ontario and the Edgewood Province and Cincinnati Arch region in the east-central United States

All genera based on fossil type species belonging to the family Mactridae are alphabetically listed in this work. The oldest records of the Mactridae come from Cretaceous deposits of North America. However, this group of bivalves has been worldwide recorded from the Paleogene and Neogene. An emended diagnosis for each genus is herein provided. In addition to that, type species, type localities, and occurrences are included. For each genus, a remarks section includes the most recent published taxonomic opinions. Nevertheless, in some cases, new taxonomic decisions based on morphological analysis of types have been taken. Genera based on extant type species are excluded from this work. Forty-five genera are listed herein and type material has been reproduced wherever possible. Ionesimactra nom. nov. is proposed as a replacement name for Caspimactra Ionesi (non Caspimactra Ali-Zade and Kabakova). This work constitutes the basis for future revisions related to fossil taxa of the family Mactridae from different regions.

The Late Cretaceous gastropods from Turkey have been insufficiently studied. We herein present a taxonomic study of the subgenus Trochactaeon (Trochactaeon) from the upper part of the Karababa Formation (Karababa-C member) at the Saytepe section in southeastern Turkey. The Upper Cretaceous fossil-bearing Karababa Formation, cropping out in southeastern Turkey, yields a remarkable assemblage of acteonellid gastropods and rudist bivalves. The subgenus Trochactaeon, a very successful and widespread taxon within the heterobranch gastropod family Acteonellidae, dominated acteonellid assemblages throughout the Late Cretaceous. This is the first record of Trochactaeon (Trochactaeon) giganteus subglobosus from Turkey. It is from a single lower Campanian bed in the upper part of the Karababa Formation of the Gölbaşı region (south of Adıyaman), corresponding to the northwestern part of the Arabian Platform. This record complements information on the temporal and spatial distribution of Trochactaeon at the southern margin of the Tethyan Ocean during the last part of the Cretaceous Period. This discovery increases the documented diversity of the paleofauna from the Upper Cretaceous succession in southeastern Turkey and provides new insights into the paleoenvironment of the carbonate ramp of the northern Arabian plate, and the paleobiogeography of Campanian gastropods in general.

Acteonellids were one of the most significant groups of marine macro-invertebrates in the Late Cretaceous biota of the Tethyan Realm. They were common faunal elements associated with Cretaceous carbonate platform communities most notable for their abundance of rudist frameworks and thrived in coeval lagoons. The Upper Cretaceous fossil-bearing Karababa Formation, cropping out in southeastern Turkey, yields a remarkable assemblage of acteonellid gastropods and rudists. Cretaceous gastropods from sedimentary successions in Turkey barely have been studied over the past 80 years. The subgenus Trochactaeon, a very successful and widespread taxon of heterobranch gastropods within the family Acteonellidae, dominated acteonellid assemblages throughout the Late Cretaceous. In the present work, we present the first record of Trochactaeon (Trochactaeon) giganteus subglobosus from Turkey. It is from a single lower Campanian bed in the upper part of the Karababa Formation of the Gölbaşı region (south of Adıyaman), corresponding to the northwestern part of the Arabian Platform. This record complements information on the temporal and spatial distribution of Trochactaeon at the southern margin of the Tethyan Ocean during the last part of the Cretaceous Period. This discovery increases the documented diversity of the paleofauna from the Upper Cretaceous succession in southeastern Turkey and provides new insights into the paleoenvironment of the carbonate ramp of the northern Arabian plate, and the paleobiogeography of Campanian gastropods in general.

A newly discovered trilobite fauna from the Cambrian Honey Creek Formation marks a distinct interval that follows an extinction event. Dominated by the genus Monocheilus in association with Ptychaspis, it resembles faunas from Alberta, Canada, and the Upper Mississippi Valley region of the United States. Ptychaspis bullasa Lochman and Hu, 1959 is a species that has been reported widely in North America. However, restudy of various museum collections shows that the various occurrences record a set of more narrowly distributed species. The pattern of distribution is similar to groups of modern “pseudocryptic species” identified by a combination of genetic and anatomical data.

The Cambrian (Jiangshanian, Sunwaptan) Honey Creek Formation in the Wichita Mountains region of Oklahoma yielded a new fauna dominated by Monocheilus Resser, 1937 (senior synonym of Stigmacephalus Resser, 1937) in association with Ptychaspis Hall, 1863. It occupies the same stratigraphic position as similar faunas in the Upper Mississippi Valley and Alberta, lying a little above an interval characterized by species of Taenicephalus Ulrich and Resser in Walcott, 1924 and Orygmaspis Resser, 1937. Revision of Ptychaspis bullasa Lochman and Hu, 1959 from type material from Idaho and sclerites attributed to the species from Texas reveals a plexus of pseudocryptic species that share tuberculate sculpture on the cranidium. New species are Monocheilus reginae, Monocheilus richardi, Ptychaspis occulta, and Ptychaspis matuszaki.

The suborder Phacopina, characterized by schizochroal eyes, is among the most common groups of trilobites in Devonian strata. The marine sediments of the Famennian in western Junggar, Xinjiang, contain abundant low-disparity phacopids, which have previously been designated to Omegops accipitrinus mobilis, Phacops circumspectans tuberculosus, and Omegops cornelius on the basis of small numbers of poorly preserved specimens. In this study, these phacopids were identified as two new species of Omegops, O. honggulelengensis n. sp. and O. xiangi n. sp., on the basis of nearly 200 well-preserved specimens. The intraspecific variations of eye lenses of these specimens were quantitatively analyzed. On the basis of differences in the total number, number of dorsoventral files, and arrangement of the eye lenses, the absence of lenses in the middle part of the visual surface, and asymmetry of the number and/or arrangement of lenses in the two eyes, it was concluded that the reasons for intraspecific variation in eye lenses of Late Devonian Omegops from western Junggar were different from previously described factors but were likely genetic or embryological malfunctions or abnormalities caused by pathological conditions. Diversity of lenses in the schizochroal eyes shows that the number and arrangement of eye lenses was not stable in Phacopina. Therefore, many specimens are needed for quantitative study to determine the true characteristics of the number or arrangement of eye lenses when these features are used in the systematic taxonomy of Phacopina.

Crinoids, the group known today as the sea lilies, were a major constituent of ocean environments from the late Carboniferous (323–299 million years ago). However, crinoid fossil-forming potential is poor, and they typically fell apart quickly after death. This limits our ability to study much about their life histories, including how they would have grown. Through the discovery of an area of exceptional fossil preservation in the Barnsdall Formation of Oklahoma, we have a rare chance to learn about the growth of one of these species of crinoids, Erisocrinus typus. Here we perform a growth analysis of a well-preserved series of fossils and discuss the patterns that it showed from its juvenile stage to adulthood.

Crinoids were major constituents of late Carboniferous (Pennsylvanian) marine ecosystems, but their rapid disarticulation rates after death result in few well-preserved specimens, limiting the study of their growth. This is amplified for cladids, who had among the highest disarticulation rates of all Paleozoic crinoids due to the relatively loose suturing of the calyx plates. However, Erisocrinus typus Meek and Worthen, 1865 has been found in unusually large numbers, most preserved as cups but some as nearly complete crowns, in the Barnsdall Formation in Oklahoma. The Barnsdall Formation, a Koncentrat Lagerstätte, is composed predominantly of fine- to medium-grained sandstone, overlain by mudstone and shale; severe compaction of the fossils in the mudstone and shale layer in this formation allowed for exceptional preservation of the plates. Herein, we summarize a growth study based on 10 crowns of E. typus, showcasing a well-defined growth series of this species from the Barnsdall Formation, including fossils from juvenile stages of development, which are rarely preserved. We used high-resolution photographs imported into ImageJ and recorded measurements of the cup and arms for all nondistorted or disarticulated plates. Results show that the plates of the cup grew anisometrically with both positive and negative allometry. The primibrachial plates of E. typus grew with positive allometry. The brachial plates started as uniserial (i.e., cuneiform) as juveniles but shifted to be biserial. Erisocrinus typus broadly shares similar growth trajectories with other cladids. These growth patterns provide insight into feeding strategies and can aid in understanding crinoid evolutionary paleoecological trends.

In southern Guizhou, South China, there are well-exposed shallow-water deposits of the Jiusi and Shangsi formations, which consist of platform limestones mixed with shales and sandstones. Conodonts, ancient tooth-like fossils, were found in the limestones and were dominated by two groups: the Cavusgnathus aff. Cav. unicornis and Clydagnathus windsorensis in the upper Jiusi Formation and the Cavusgnathus unicornis in the lowest Shangsi Formation. Vogelgnathus campbelli with small lateral denticles was found for the first time in Eastern Paleotethys. The Cavusgnathus unicornis is used as a marker for the regional Shangsian stage and correlated to other conodont zones marked by similar species in North America and Europe of middle Visean.

The typical Mississippian shallow-water deposits of the Jiusi and Shangsi formations are well exposed in the Yashui section in southern Guizhou, South China. The strata are composed mainly of platform limestones intercalated with shales and sandstones. Conodonts obtained from the limestones are dominated by two assemblages of cavusgnathids: the Cavusgnathus aff. Cav. unicornis and Clydagnathus windsorensis assemblage from the upper Jiusi Formation and the Cavusgnathus unicornis assemblage from the lowest Shangsi Formation. Vogelgnathus campbelli (Rexroad, 1957) is reported for the first time in Eastern Paleotethys and is characterized by small lateral denticles. The evolutionary first occurrence of Cavusgnathus unicornis Youngquist and Miller, 1949 is recognized as a marker for the regional Shangsian stage. This biostratigraphic datum is interpreted to be correlative with other shallow-water conodont zones marked by Cavusgnathus unicornis s.l. and similar species from North America and Europe.

Toyotamaphimeia is an extinct crocodylian lineage whose name is derived from a mythological Japanese princess. Here, we re-examine the type specimens of a long-forgotten species: Tomistoma taiwanicus from the Pleistocene of Tainan (Taiwan) and revise its taxonomic status to Toyotamaphimeia taiwanicus n. comb., leading to the first recognized species of Toyotamaphimeia outside Japan. Our phylogenetic analyses also support this taxonomic assignment and, more interestingly, further suggest an East Asian lineage. In addition, Toyotamaphimeia taiwanicus n. comb. represents a tropical species, resolving a long-standing puzzle of why Toyotamaphimeia only inhabited a much higher latitudinal area (Japan). Given the large body size of Toyotamaphimeia taiwanicus n. comb. (∼7 m) and the fact that it is geologically older than Toyotamaphimeia machikanensis from Japan, we propose a novel evolutionary scenario: the genus Toyotamaphimeia originated in Taiwan and evolved to a large body size with gigantothermic physiology, which resulted in migration out of Taiwan and dispersal farther north to Japan. Our taxonomic identification shows the presence of an extinct endemic crocodylian species from the Pleistocene of Taiwan with large-scale paleogeographic implications. This study, with our recent progress in vertebrate paleontology in Taiwan, should provoke more in-depth paleontological research on the Pleistocene extinction.

Shorebirds and allies form the avian order Charadriiformes and have a poor early Cenozoic fossil record. We report charadriiform and charadriiform-like birds from the early Eocene London Clay of Walton-on-the-Naze (Essex, UK). A partial skeleton of a small modern-type charadriiform is described as a new species, Charadriisimilis essexensis n. gen. n. sp., and most closely resembles species of the Charadrii, the group including plovers, stilts, oystercatchers, and other “wader-like” shorebirds. With an age of about 53 million years, this is one of the geologically oldest charadriiform species known to date. The new material also includes fossils of the charadriiform-like taxon Scandiavis, which was before known only from the early Eocene Fur Formation in Denmark. Scandiavis is the best-represented archaic charadriiform bird, and together with the more “modern-type” Charadriisimilis, it informs the evolutionary history of charadriiform birds.

We report charadriiform and charadriiform-like birds from the early Eocene London Clay of Walton-on-the-Naze (Essex, UK). A partial skeleton of a small modern-type charadriiform is described as a new species, Charadriisimilis essexensis n. gen. n. sp., and most closely resembles taxa of the Charadrii (plovers, stilts, oystercatchers, and other “wader-like” shorebirds). Affinities to this clade were also supported by phylogenetic analyses, which placed the fossil as the sister taxon of either the Burhinidae or all crown group Charadrii. In addition, we identify specimens of the charadriiform-like taxon Scandiavis, which was before known only from the early Eocene Fur Formation in Denmark. Associated limb elements of two individuals are classified as Scandiavis cf. mikkelseni Bertelli et al., 2013, and remains of two further individuals are tentatively assigned to Scandiavis. The presence of a processus supracondylaris dorsalis on the previously unknown humerus corroborates charadriiform affinities of Scandiavis, whereas a plesiomorphic hypotarsus morphology indicates a position outside crown group Charadriiformes. Charadriisimilis essexensis is one of the earliest modern-type charadriiforms, and the holotype of the species is the most substantial early Paleogene fossil record of a charadriiform bird. Together with Scandiavis, as the best-represented taxon to be considered as a stem group charadriiform, it provides the basis for an improved understanding of the evolutionary history of charadriiform birds.