Three gogiid eocrinoids, numbering in the thousands of specimens, are well known from the lower Cambrian (Stage 4) Balang Formation (Guizhoueocrinus yui) and basal middle Cambrian (Stage 5) Kaili Formation (Kaili Biota) (Sinoeocrinus lui and Globoeocrinus globulus) that resided on the Yangtze-South China Plate (modern Guizhou Province, China). In each species a complete ontogenetic sequence, using thecal height (TH) as a scale, juvenile stage (early, middle, and late substages), mature stage (early, middle, and late substages), and a gerontic stage can be identified. Sutural pores appeared in an orderly sequence; below the ambulacrals, above the stalk and generally over the theca, in that order. In younger species their emplacement and growth was commonly precocious relative to G. yui. Also, their shape ranges from circular to oval to triangular in a single growth sequence, after the establishment of the 2-1-2 pattern; brachioles were added in series of five and were also precocious in time of occurrence in younger species. Thecae in younger species tend to retain juvenile aspects relative to G. yui. All of these species lived in outer shelf settings in fine-grained, organic-rich siliciclastics.

Little is known about the habit and spatial distribution of Early Permian tropical vegetation, a sharp contrast with the Pennsylvanian from which many in-situ “T⁰” assemblages are known. Even less is known about the potential interaction of plants and vertebrates. Here we report the discovery of a small stand of 34 probable Supaia White plants from the Abo Formation of New Mexico. The plants were growing on a mudflat, subject to periodic flooding and exposure. The same mudflat hosts trackways of vertebrates that appear to have walked around or between the Supaia plants. The stems are preserved as molds, and vary from 20 mm to 70 mm in diameter, averaging 42.4 mm, indicating heights of approximately 2.5–4 m. The plants, which may be described as small trees given their estimated height, are as close as 110 mm to their nearest neighbor and average nearly 300 mm apart. A series of lines or filled fissures, which we interpret as roots, radiates from the base of each stem. Leaves of Supaia thinfeldioides White are the only foliage found in association with these stems, on bedding planes above and at the base of the lowest expression of the stem molds. Associated vertebrate trackways either congregate around some of the stems or wend their way between the stems and include those of a single large temnospondyl amphibian (Limnopus Marsh) and many of small predatory parareptiles (Dromopus Marsh). This study demonstrates that S. thinfeldiodes were small-statured, weedy, opportunistic plants. It also shows that contemporaneous vertebrates prowled such environments, presumably either for food, shelter, or both given detectable pace and path.

Two new kirkocystid mitrate stylophorans (Echinodermata, Homalozoa) and a new possible solute (Echinodermata, Homalozoa) are described from the Early Ordovician of the western United States. The mitrates are among the earliest members of their clade to appear near the beginning of the Ordovician Radiation. Anatifopsis ninemilensis new species comes from the Ninemile Shale in central Nevada and the McKelligon Canyon Formation in west Texas. Anatifopsis fillmorensis new species comes from the middle Fillmore Formation in western Utah and a Ninemile Shale equivalent limestone bed in southern Nevada. The possible solute Drepanocystis dubius new genus new species from the lower Wah Wah Limestone in western Utah, shows unusual morphology with an elongate theca and a long arm shaped like a sickle.

The thickness ratios of shell whorls ( = whorl breadth/shell diameter) in the ammonoids Damesites sugata (Forbes, 1845), Hypophylloceras subramosum (Shimizu, 1934), and Gaudryceras tenuiliratum Yabe, 1903 from Late Cretaceous outer shelf deposits in the Kotanbetsu area of northwestern Hokkaido, Japan, were examined in order to determine their mode of migration. The thickness ratios of D. sugata differ significantly with depth on the outer shelf environment but show no significant difference laterally at a similar depth. These results suggest that D. sugata did not frequently migrate to different depths on the outer shelf environment but tended to live and migrate laterally at a similar depth on the outer shelf. The thickness ratios of H. subramosum and G. tenuiliratum show no significant difference between different depths on the outer shelf environment or for lateral direction at a similar depth. This suggests that H. subramosum and G. tenuiliratum frequently migrated at different depths on the outer shelf environment and laterally at a similar depth. There is no difference in hatchling diameters in all the examined species at different depths on the outer shelf environment, suggesting that the thickness ratios became manifest after the post-hatchling stage due to limited migration, which would have been in a nektobenthic habitat. The various modes of migration in the study area are reconstructed in this study, suggesting diversified paleoecology of Late Cretaceous ammonoids.

Callianassids are among the most commonly found decapod crustacean fossils but their generic assignment is often difficult. Numerous cheliped remains have been found in the upper Miocene deposits of southwest Spain allowing description of a new species of a ghost shrimp, Podocallichirus laepaensis. The assignment of the new form to the respective genus is based mainly on the morphology of the major cheliped merus and provides useful implications for paleontological studies. Podocallichirus laepaensis is the first fossil record of the genus known to date. Several specimens preserved in association with and within Ophiomorpha traces are interpreted as in situ preservation. Thus, the new ghost shrimp is identified as the producer of trace fossils.

The fossil isopod crustacean genus Archaeoniscus has been known to occur in England, France and Germany during the Upper Jurassic, and in Mexico and Egypt during the Lower Cretaceous. The morphology of this genus is unique in having dorsoventrally compressed body, the cephalon set deeply into the first pereionite, pleon as wide as pereion, and a broad semicircular pleotelson. These features have resulted in placing the classification of the genus in the monotypic family Archaeoniscidae. However, due to the lack of detailed morphological data, suprafamilial classification of this genus has remained unclear, as well as its ecology and lifestyle. Here we report Archaeoniscus coreaensis n. sp. from the Jinju Formation, Gyeongsang Basin, Korea. The occurrence of Archaeoniscus in the East Asia implies that the genus may have had a worldwide distribution. The Gyeongsang Basin was a Cretaceous backarc basin, which consists of exclusively non-marine sedimentary sequences. The occurrence of this genus, therefore, indicates that Archaeoniscus successfully adapted to a freshwater ecosystem as well. Detailed anatomy including antennulae, antennae, pereiopods, and uropods was observed from well-preserved multiple specimens, which allows better understanding of the morphology of Archaeoniscus. The axial structure in the posterior part of the body, which was previously interpreted as a unique brood pouch characterizing the family, turned out to be a remnant of the hindgut. Females of all isopods and most of the members of the superorder Peracarida have a thoracic ventral brood pouch, modified from the thoracic coxal endites. Based on the morphology of the largely unmodified ambulatory pereiopods of A. coreaensis, the possibility of Archaeoniscus being ectoparasitic is discounted. Instead, the flattened body and the form of limbs of A. coreaensis would have been suitable for a benthic lifestyle.

The first fly fossil discovered from the Upper Jurassic Talbragar Fish Bed in Australia is described and illustrated. Based on a single, well preserved wing, Calosargus (Calosargus) talbragarensis new species is assigned to the extinct brachyceran family Archisargidae. Wing morphology suggests a relationship between this extinct family and Stratiomyidae. The Archisargidae have so far only been found in China, Kazakhstan and Mongolia. Calosargus Mostovski, 1997 currently comprises seven species from the Callovian (late Middle Jurassic) of China and three species from the Oxfordian (early Upper Jurassic) of Kazakhstan. This oldest brachyceran fossil from Australia and first record of the Archisargidae in the southern hemisphere presents evidence that higher flies were present in this region in the Jurassic, when this group is thought to have commenced its diversification.

A number of immature and mature exoskeletons allow the first detailed description of the ontogeny of the early Cambrian redlichiid trilobite Metaredlichia cylindrica, from black shale of the Shuijingtuo Formation in Hubei Province, South China. The material includes numerous complete protaspides, within which two stages can be differentiated according to the appearance of a shallow furrow that separates the protopygidial area from the protocranidium. Also, identification of the subsequent ontogenetic stages, including meraspides and holaspides, depends on isolated cranidia that display prominent morphological changes such as the contraction of frontal glabellar lobe, appearance of the fourth pair of glabellar furrows, and modification of the facial suture from proparian to opisthoparian. Incorporating the whole ontogenetic sequence allows us not only to trace the developmental trends of various structures with growth, but also to assign the protaspides to their adults correctly, particularly with the help of meraspid specimens.

Larval and juvenile growth stages of myoconchid bivalves (family Kalenteridae) are illustrated and described for the first time. Excellently preserved shells of Myoconcha crassa J. Sowerby, 1824 from the middle Bathonian (Middle Jurassic) clay/silt deposits of southern Poland reveal that the prodissoconch in this taxon is large (exceeding 350 µm in length) and characterized by a prominent, collar-like structure arising from the demarcation to the dissoconch. Similar prodissoconch morphology has not been described previously in any other bivalve genus. The large size and absence of a prodissoconch II strongly suggest a non-planktotrophic development of the larvae, indicating either simple lecithotrophy or long-term brooding and parental care for the larvae in this species. Consequently, the new discovery constitutes the earliest well-documented record of non-planktotrophic development in the Bivalvia. The shell of Myoconcha crassa is composed of an outer cross-lamellar layer and an inner complex cross-lamellar layer. This composition suggests that the Kalenteridae may be included in the Carditida rather than the Palaeoheterodonta or Anomalodesmata. The genus Pseudomyoconcha Rossi Ronchetti and Allasinaz, 1966 is rejected herein and considered as a junior synonym of Myoconcha J. Sowerby, 1824.

The Araripe Basin is the most extensive interior basin in northeastern Brazil, comprising areas of Ceará, Piauí and Pernambuco states. The Santana Formation, attributed to the Aptian–?lower Albian age of the basin, is subdivided into two members, Crato and Romualdo, which bear an abundant fossil record of plant fragments, arthropods and vertebrates, especially 3D-preserved fishes. The present study focuses on the taxonomy, ontogeny and paleoecology of two ostracode species from the Romualdo Member and the top section of the Crato Member (Ipubi layers), Harbinia salitrensis (Krömmelbein and Weber, 1971) emend. and H. alta new species. The ontogenetic series for both species are illustrated, except for the A-8 instar; H. salitrensis is also redescribed. The present work is also the first to produce quantitative information about the paleoecology of the Santana Formation based on ostracode populations. The results obtained from analyses of the population age-structure of both species, in addition to dominance (Simpson) and diversity index (Shannon) values, corroborated previous data on the studied sequence. According to these results, the strata were deposited in a limnic, low-to-moderate energy environment with salinity levels varying from oligohaline to mesohaline. The new data indicate the possibility of these environments also being hypersaline.

The middle and late Permian to Triassic sequence of carbonate rocks in the Takachiho area, central Kyushu, Japan, originated as a Panthalassan seamount and formed parts of far-traveled accreted terranes. This succession is divided into the Permian Guadalupian Iwato and Lopingian Mitai formations, and the Triassic Kamura Formation. The Iwato Formation is further into three zones, the Neoschwagerina, Yabeina higoensis, and Neoendothyra permica zones in ascending order; the Mitai Formation includes the Nanlingella suzukii Zone. Biotic turnovers are recorded twice in the Iwato and Mitai formations. The first and more remarkable biotic event is the total disappearance of fusulines at the top of the Yabeina higoensis Zone. The Neoendothyra permica Zone is characterized by black fine-grained micritic limestones having only sparse non-fusuline foraminifers. The second biotic event is the first appearance of Wuchiapingian fusulines by which the Nanlingella suzukii Zone is defined. The Capitanian–Wuchiapingian boundary is drawn between the Neoendothyra permica and Nanlingella suzukii zones. Above this boundary both the numbers of individual foraminifers and diversity of species gradually increase. The turnovers recorded in the Takachiho area were the result of late Capitanian–Wuchiapingian environmental changes which were sufficient to cause the disappearance of large, multi-chambered fusulines and allow the new appearance of an ‘ultimate’ Paleozoic foraminiferal assemblage. Ten species of foraminifers, including Yabeina higoensis and Yabeina Columbiana, are described.

A new turtle, Puentemys mushaisaensis, from the middle to late Paleocene Cerrejón Formation of Colombia, is described on the basis of a partial skull and many partial to nearly complete carapaces and plastrons representing multiple ontogenetic stages. Whereas P. mushaisaensis is unique in aspects of its shell morphology, it shares many diagnostic characteristics of bothremydid pleurodirans, including a long exoccipital-quadrate contact, a very low and rounded almost circular carapace, and a thinner internal bone cortex than that of the external cortex in both the carapace and plastron. With a maximum carapacial length of 151 cm, P. mushaisaensis is the largest known bothremydid turtle and represents the first occurrence of bothremydids in the Paleogene of South American tropics. Results from a cladistic analysis of bothremydids indicate that P. mushaisaensis shares a close relationship with Foxemys mechinorum from the Late Cretaceous of Europe, indicating a wide-spread geographical distribution for bothremydines during the Late Cretaceous–Paleocene.

The Early Cretaceous non-marine ostracod genera Hourcqia Krömmelbein and Pattersoncypris Bate are reinstated. A previously published referral of Hourcqia to Cypridea Bosquet is rejected due to the absence of an anteroventral rostrum in the holotype of the type species Hourcqia africana Krömmelbein. The genus Hourcqia is characterized by an “inverse” valve ratio (right valve larger than left) and the lack of an anteroventral rostrum, and the diagnosis of the genus is broadened to accommodate ornamented forms, resulting in the acceptance of five species: Hourcqia africana, H. confluens (Krömmelbein and Weber), H. kouilouensis (Grosdidier), H. bateke (Grosdidier) and H. sylvesterbradleyi (Bate). The previously published synonymy of Pattersoncypris with the genus Harbinia Tsao is also rejected. The diagnosis of Pattersoncypris is refined, meaning that three species are recognized: Pattersoncypris micropapillosa Bate, P. salitrensis (Krömmelbein and Weber), and P. sinuata (Krömmelbein and Weber). The new genus Kroemmelbeincypris is erected for two species initially assigned to Hourcqia, and subsequently to Pattersoncypris and Harbinia by different authors: Kroemmelbeincypris symmetrica (Krömmelbein and Weber) and K. angulata (Krömmelbein and Weber). The genus Hourcqia is diagnostic of latest Barremian non-marine settings, whilst Pattersoncypris and Kroemmelbeincypris characterize Aptian saline lacustrine environments. The geographic ranges of all three genera are restricted to northeastern and eastern Brazil and northern and western Africa, though a species of Pattersoncypris (P. dakotaensis Tibert and Colin) is also present in the United States.