The Ediacara Biota is a suite of globally distributed, exceptionally-preserved, soft-bodied organisms appearing in the fossil record from 575 million years ago to the base of the Cambrian. Nilpena Ediacara National Park (NENP) in the Flinders Ranges of South Australia preserves one of the most morphologically and taxonomically diverse assemblages of this period. Tribrachidium heraldicum is one of the more abundant taxa at this site (> 200 specimens) and is described as a circular organism, ∼3–50 mm in diameter, showing triradial symmetry. Here we describe a new species from NENP within the Tribrachidium genus: Tribrachidium gehlingi new species. This new species has three main arm-like structures that are slightly curved and do not reach the outer margin. There are three secondary arm-like structures that are approximately half of the length of the main arms and it is, overall, lower in relief. The process of burial and deformation are unlikely to be the cause of these morphological differences because both species co-occur within the same bedding horizon.

Tribrachidium heraldicum Glaessner in Glaessner and Daily, 1959 is a triradial Ediacaran organism found in abundance within the Ediacara Member of the Flinders Ranges, South Australia. Here we report and describe a new species within the genus Tribrachidium Glaessner in Glaessner and Daily, 1959: Tribrachidium gehlingi new species from Nilpena Ediacara National Park (NENP), South Australia. Tribrachidium gehlingi n. sp. has low relief and three slightly curved, main arm-like structures that leave a conspicuous gap between the end of the arm-like structures and rim. In place of the ‘bulla’ found on T. herladicum, there are three secondary arm-like structures approximately half of the length of the main arm-like structures. Key morphological differences between the two species are statistically significantly different. Additionally, the species occur together within the same fossiliferous event horizons, indicating that the observed morphological differences are unlikely a result of taphonomy.

A major glaciation can have fundamental effects on the diversity and global distribution of marine invertebrate organisms. This study documents brachiopods from a shelly benthic marine fauna in northwestern Canada during the first major glaciation of the Phanerozoic Era, in the latest Ordovician Period. The study area in the Mackenzie Mountains was located in the northern-hemisphere tropics during the Late Ordovician. The presence of a unique glaciation-age brachiopod fauna in both the southern-hemisphere tropics of ancient North America (in today's southeastern USA) and the Mackenzie Mountains indicates the far reach of the latest Ordovician glaciation centered in the southern Polar region.

Silicified brachiopods from Hirnantian strata in three sections of the lower Whittaker Formation, Mackenzie Mountains, northwestern Canada, yielded a moderately diverse, Edgewood-type Hirnantian fauna, consisting of 13 species: Biparetis paucirugosus, Brevilamnulella laevis, Dalmanella edgewoodensis, Drabovia noixella, Eospirigerina putilla, Epitomyonia paucitropida, Epitomyonia sekwiensis, Glyptorthis papillosa new species, Gnamptorhynchos orbiculoidea, Katastrophomena mackenzii new species, K. parvicardinis, Parastrophina cf. P. minor, and Skenidioides sp. Compared to the typical Edgewood fauna of the American Midcontinent, Brevilamnulella laevis has a notably smaller shell than B. thebesensis, and is interpreted as a deeper-water form. The strong faunal affinity of the Mackenzie Mountains fauna to the Edgewood-type Hirnantian fauna is indicated by the occurrence of Biparetis, Brevilamnulella, Eospirigerina, and Gnamptorhynchos. In addition to the Edgewood type area within Laurentia, Biparetis, Eospirigerina, and Gnamptorhynchos are characteristic taxa that also occur in the Ellis Bay Formation (Hirnantian) of Anticosti Island. Multivariate and network analyses strongly support the differentiation between an Edgewood-type Hirnantian fauna in Laurentia and peri-Laurentia and the typical Hirnantia fauna of the Kosov Province in Gondwana, peri-Gondwana, South China, Kazakhstan terranes, Avalonia, and Baltica.

Tubeworms form an important part of the modern marine fauna. They were also common in the geological past. We discovered a new genus and species of tubeworms from the latest Ordovician of Estonia. These tubeworms grew on the lithified sea floor during the time of the end-Ordovician mass extinction. Our discovery helps better understand and reconstruct the marine life during this extraordinary time interval.

A new cornulitid genus and species, Porkuniconchus fragilis new genus and species, is here described from the Ärina Formation (Hirnantian, Porkuni Regional Stage) of northern Estonia. This new taxon differs from most cornulitids by having a fusiform ornamentation pattern that is somewhat similar to that of Kolihaia. All studied specimens are attached to a carbonate hardground. The hardground fauna is by abundance and encrustation area dominated by cornulitids. Other encrusters are represented only by a single sheet-like cystoporate bryozoan. The cornulitid specimens represent different growth stages, which suggest that the hardground was continuously colonized by cornulitid larvae. The high encrustation density indicates that the studied hardground may have represented a high-productivity site in the Hirnantian of the Baltic Basin.

Paleontological data from the late Paleozoic strata of western Yunnan, southwestern China, have played significant roles in understanding the history of the Cimmerian continental blocks and the Paleotethys Ocean. In this paper, we describe and illustrate brachiopod fossils from the early to middle Permian strata of western Yunnan, China. These brachiopods were collected from three beds of the Shanmutang section, and composed of three assemblages, which in ascending order include the Elivina-Etherilosia Assemblage from the top of the Kongshuhe Formation, the Spiriferella-Spiriferellina Assemblage from the base of the Dadongchang Formation, and the Waagenites-Costiferina Assemblage from the lower part of the Dadongchang Formation. The first assemblage is considered to be most likely late Sakmarian to early Artinskian, the second assemblage probably late Artinskian, and the third assemblage late Roadian to early Wordian in age. It is noticed that there is a transition from cool-water brachiopod faunas with Gondwanan affinities to mixed warm-temperate (transitional) faunas with Cathaysian elements during the Artinskian and through the Guadalupian. We consider that this phenomenon probably resulted from the Gondwana deglaciation and the northward drift of the peri-Gondwanan blocks (including the Tengchong Block) during the Cisuralian and Guadalupian.

The early to middle Permian brachiopods from the Tengchong Block in western Yunnan, southwestern China, play important roles in biostratigraphic correlation and paleogeographic inferences of tectonic units on eastern peri-Gondwana. However, detailed taxonomic studies of these brachiopods have been limited. In this paper, we provide the systematic description of three Permian brachiopod assemblages from the Shanmutang section in the northern Tengchong Block, which in ascending order include the Elivina-Etherilosia Assemblage from the top of the Kongshuhe Formation, and the Spiriferella-Spiriferellina Assemblage and the Waagenites-Costiferina Assemblage from the base and lower part, respectively, of the overlying Dadongchang Formation. Based on the biostratigraphic assessment of the brachiopod taxa as well as the age constraints from the associated fusulinid assemblages, the age of the Elivina-Etherilosia Assemblage is considered to be most likely late Sakmarian to early Artinskian, the Spiriferella-Spiriferellina Assemblage probably late Artinskian, and the Waagenites-Costiferina Assemblage late Roadian to early Wordian. A transition from cool-water faunas with Gondwanan affinities to mixed warm-temperate (transitional) faunas with Cathaysian elements is evident for the Artinskian and through the Guadalupian. The climatic transition inferred from the faunal evidence is interpreted to have resulted from the combined effect of Gondwana deglaciation and the northward drift of the peri-Gondwanan blocks (including the Tengchong Block) during the Cisuralian and Guadalupian.

Natural history museums house numerous previously undescribed species and unknown information hidden in their collections. We describe lower Carboniferous slit-bearing gastropods (Pleurotomariida and Goniasmatidae) from previously unreported gastropod collections made by Jane Longstaff (Jane Donald), one of the pioneering paleontologists of Paleozoic gastropods in the late nineteenth and early twentieth centuries. The gastropods were collected from an old quarry near Dalry, Ayrshire, Scotland. The collection consists largely of microgastropods, many of which are unusually well preserved including delicate ornament and larval shells. The collection yields ten species, three of them representing new species. The new data on earliest whorls and other shell features such as the selenizone (the shell region formed by the closure of the shell slit) improved the classification. The new findings confirm that the genus Neilsonia belongs to Pleurotomariida and is distinct from the morphologically convergent Peruvispira (Goniasmatidae). The similarities between Biarmeaspira and Baylea support previous opinions that they are closely related. Furthermore, the collection yields the oldest record of Biarmeaspira, which was previously known only from the Permian. The angulated selenizone (as in Biarmeaspira) evidently evolved several times in Pleurotomariida and the repeated appearance of this character in different groups needs further studies using phylogenetic methods.

Natural history museums house numerous previously undescribed species and unknown information hidden in their collections. We describe lower Carboniferous slit-bearing gastropods (order Pleurotomariida, subclass Vetigastropoda; and family Goniasmatidae, subclass Caenogastropoda) from previously unreported gastropod collections made by Jane Longstaff (Jane Donald), one of the pioneering paleontologists of Paleozoic gastropods in the late nineteenth and early twentieth centuries. The gastropods were collected from the Lower Limestone Formation (Visean, Brigantian) near Dalry, Ayrshire, Scotland. The collection consists largely of microgastropods, many of which are unusually well-preserved including delicate ornament and protoconchs (larval shells). Three new pleurotomariidan species are described—Biarmeaspira heidelbergerae new species, Neilsonia seussae new species, Tapinotomaria longstaffae new species—in addition to seven species belonging to Borestus Thomas, 1940, Stegocoelia (Stegocoelia) Donald, 1889, Stegocoelia (Hypergonia) Donald, 1892, Donaldospira Batten, 1966, and Platyzona Knight, 1945. The caenogastropod-type protoconch is documented for the first time in Hypergonia, which is therefore placed in Goniasmatidae. The new data confirm that Neilsonia Thomas, 1940 (type genus of Neilsoniinae) belongs to Pleurotomariida and is distinct from the morphologically convergent Peruvispira Chronic, 1949 (Goniasmatidae). The selenizone morphology is identical in Biarmeaspira Mazaev, 2006 and Baylea de Koninck, 1883 during their early ontogeny, and Biarmeaspira develops an angulation on the selenizone (the diagnostic feature) in late ontogeny. This corroborates earlier suggestions that Biarmeaspira evolved from Baylea. Biarmeaspira heidelbergerae n. sp. is the first Carboniferous record of Biarmeaspira, which was previously only known from the Permian. The angulated selenizone evidently evolved several times in Pleurotomariida and the repeated appearance of this character in different groups (e.g., Phymatopleuridae, Eotomariidae, Pleurotomariidae) needs further studies using phylogenetic methods.

Ammonoids are an extinct group of cephalopods that lived from the Devonian until the end of the Cretaceous periods. In the Jurassic and Cretaceous periods, there were four suborders, Ancyloceratina, Perisphinctina, Lytoceratina, and Phylloceratina. Ancyloceratina formed a conch with detached whorls (open coiling) or non-planispiral coiling. The origin of Ancyloceratina remains unclear. In this study, we analyzed conch morphology in detail using specimens collected from southern India, Madagascar, and Japan. As a result, we found a common trend in conch morphology in early ontogeny of Ancyloceratina and Perisphinctina. We think that the similarity of conch morphology suggests a closer relationship between them, relative to Lytoceratina or Phylloceratina. Our findings are meaningful to consider the phylogenetic relationship and evolution of Jurassic–Cretaceous ammonoids.

We analyzed the ontogenetic trajectories of conch morphology and septal spacing between successive chambers in Cretaceous ammonoids (suborders Perisphinctina and Ancyloceratina) collected from southern India, Madagascar, and Japan. All examined species, except for the family Collignoniceratidae, exhibited similar characteristics during early ontogeny. The common ontogenetic trajectories of septal spacing show a cycle comprising an increase and a subsequent decrease in septal spacing during early ontogeny. The conch diameters at the end of the cycle were estimated to be 1–4 mm. The conch shape (aperture height and whorl expansion rate) covariably changed at this conch diameter. Such covariable changes are commonly recognized in the suborders Perisphinctina and Ancyloceratina. The similarity in the ontogenetic trajectories of conch morphology implies a closer phylogenetic relationship between these suborders compared to Lytoceratina or Phylloceratina.

Captorhinidae is a diverse group of small to medium-sized reptiles known from the Pennsylvanian and Permian. Some of its species evolved jaws with multiple rows of teeth that suggest a diet of high-fiber plant material. The authors describe in detail the known material of an early captorhinid with multiple tooth rows from the lower Permian (Cisuralian) of Oklahoma and north-central Texas. Because it differs from other known captorhinid species, it is placed in its own new genus, Sumidadectes.

‘Captorhinikos’ chozaensis Olson, 1954 is a captorhinid eureptile with multiple tooth rows from the lower Permian (Cisuralian: Kungurian) Clear Fork Group of north-central Texas and the Hennessey Formation of Oklahoma. It has five maxillary and four dentary tooth rows. We re-examined the available specimens referred to ‘Captorhinikos’ chozaensis to elucidate aspects of its skeletal structure and assess its phylogenetic relationships. Our parsimony analysis confirmed previous suggestions that this taxon is not referable to the same taxon as Captorhinikos valensis Olson, 1954 (type species of the genus) and ‘Captorhinikos’ parvus Olson, 1970 and thus is placed in its own new genus, Sumidadectes. It also recovered Sumidadectes chozaensis n. comb. as the earliest-diverging moradisaurine captorhinid.

The family Talpidae (moles) is a family of insectivores displaying a wide range of locomotor habits and consisting of semi-aquatic, terrestrial, and fossorial species. Although the modern diversity of Talpidae is relatively low, the paleodiversity of Talpidae during the Late Miocene (from about 11.5 to about 5.5 million years ago) was extremely high, especially in Central Europe. This is confirmed by the identification of eleven talpid species in several localities from Slovakia, including a new species of desman, Archaeodesmana dissona new species. Whereas the terrestrial moles are commonly found in all localities, the fossorial talpids are almost restricted to the earliest part of the Late Miocene, the Vallesian (from about 11.5 to about 9.0 million years ago). On the other hand, the desmans progressively became dominant in the beginning of the Turolian (from about 9.0 to about 5.5 million years). The high diversity of Talpidae in Central Europe is explained by the high resources and heterogeneous environments of the region, somehow reducing the pressure of competition for morphologically and ecologically similar species. The evolution of the talpid fauna reflects the environmental changes that occurred in Slovakia between the Vallesian and the Turolian. Additionnally, new information has been obtained on the morphology and phylogeny of the identified species, which are: Desmanella rietscheli, Desmanella dubia, Archaeodesmana vinea, Archaeodesmana dissona n. sp., Gerhardstorchia biradicata, Gerhardstorchia sp., Proscapanus minor, Proscapanus austriacus, Talpa cf. T. minuta, Urotrichini gen. and sp. indet., and Desmanodon cf. D. fluegeli.

Central Europe is an area of high diversity for the Talpidae (Eulipotyphla, Mammalia) during the Late Miocene. The assemblages from Slovakia (Borský Svätý Jur, Krásno, Pezinok, Šalgovce, Studienka, Triblavina) are no exception with their abundant material representing eleven species. The uropsiline Desmanella is represented by D. rietscheli and D. dubia. Desmanini fossils are attributed to Archaeodesmana vinea, Archaeodesmana dissona new species, Gerhardstorchia biradicata, and Gerhardstorchia sp. The scalopines Proscapanus minor and P. austriacus are well recorded in the Vallesian localities and support the emergence of P. austriacus before the MN9/10 transition. Talpini and Urotrichini are especially rare and only represented by Talpa cf. T. minuta and Urotrichini gen. sp. indet. Finally, we identified the youngest occurrence of Desmanodon in Europe, D. cf. D. fluegeli, at the MN9 locality of Borský Svätý Jur. The high diversity in the Late Miocene Central European is partly explained by the co-occurrence of the competing Scalopini and Talpini during the Vallesian, indicating high resource environments. The decline of these tribes, followed by the success of the desmans during the Turolian, appears as a consequence of regional environmental changes.