The Middle Cambrian eocrinoid genera Lyracystis Sprinkle and Collins, 2006, from western Laurentia and Balangicystis Parsley and Zhao, 2006, from South China, described in the same year, have turned out to be closely related genera assigned to the Family Lyracystidae. Both have erect, lyre-shaped, arm-like, brachiolebearing, feeding appendages, here termed exothecal ambulacra, that are not homologous to crinoid arms. They also have a long, multiplated stalk to elevate the theca and feeding appendages well above the sea floor, making them among the highest tiered echinoderm suspension feeders known from the Middle Cambrian. The long stalk was either inserted a short distance into the muddy sediment, or attached to rare skeletal fragments lying on the sea floor. Both genera seem well adapted to quiet-water or slow-current conditions in deeper water (150-200 m) on the outer shelf or upper slope of their respective continents.

A dorsal valve of an Upper Cambrian lingulate brachiopod exhibits a repair scar on the anterior lateral edge of its larval shell. This species is characterized by an abrupt change in ornamentation from larval to postlarval growth. Shell material secreted in the injured area after the damage occurred exhibits ornamentation that is characteristic of postlarval growth, although equivalent growth exhibits characteristics of the larval stage. A break in the edge of the shell is visible, and the growth lines of the larval and postlarval shell were distorted until the broken area was filled in. Damage to the surface of the shell is interpreted to have been caused by the same event. Modern lingulate brachiopod larvae are planktotrophic and are interpreted to have been so throughout their long geologic history. Therefore, an environmental cause of shell damage seems unlikely and the injuries are interpreted to have been caused by an unknown durophagous predator. This specimen offers evidence that lingulate brachiopod larvae were able to survive shell breakage and repair their shells.

Recent cladistic analyses have all suggested a diapsid origin of ichthyosaurs. However, an intermediate evolutionary stage of the lower temporal region of ichthyosaurian skull between basal diapsids and derived ichthyosaurs has been absent from the fossil record. Here we describe the cranial skeleton of a new mixosaurid ichthyosaur specimen with a well-preserved lower temporal region from the Anisian Guanling Formation of eastern Yunnan. It is characterized by the most primitive lower temporal region within known ichthyosaurs. The primitive characters of the lower temporal region include both external and internal separation between the jugal and the quadratojugal, an anterior process of the quadratojugal, an apparent posteroventral process of the jugal, and a large lower temporal opening surrounded by the jugal, the postorbital, the squamosal, and the quadratojugal. The lower temporal region of this specimen provides the most direct evidence to the diapsid origin of ichthyosaurs. It also suggests that the disappearance of the lower temporal fenestra is caused initially by the reduction of the lower temporal arcade rather than the enlargement of the surrounding bones.

Two new specimens of a trigonotarbid arachnid are described from Upper Pennsylvanian (Virgilian) rocks of Kansas, U.S.A., from a horizon which elsewhere has yielded scorpion and mite remains. They are the first representatives of the arachnid order Trigonotarbida to be found in Kansas. The specimens are referred to the genus Anthracomartus but are not identified to species pending revision of the American anthracomartids.

Ediacaran trace fossils are becoming an increasingly less common component of the total Precambrian fossil record as structures previously interpreted as trace fossils are reinterpreted as body fossils by utilizing qualitative criteria. Two morphotypes, Form E and Form F of Glaessner (1969), interpreted as trace fossils from the Ediacara Member of the Rawnsley Quartzite in South Australia are shown here to be body fossils of a single, previously unidentified tubular constructional morphology formally described herein as Somatohelix sinuosus n. gen. n. sp. S. sinuosus is 2-7 mm wide and 3-14 cm long and is preserved as sinusoidal casts and molds on the base of beds. Well-preserved examples of this fossil preserve distinct body fossil traits such as folding, current alignment, and potential attachment to holdfasts. Nearly 200 specimens of this fossil have been documented from reconstructed bedding surfaces within the Ediacara Member. When viewed in isolated hand sample, many of these specimens resemble ichnofossils. However, the ability to view large quantities of reassembled and successive bedding surfaces within specific outcrops of the Ediacara Member provides a new perspective, revealing that isolated specimens of rectilinear grooves on bed bases are not trace fossils but are poorly preserved specimens of S. sinuosus. Variation in the quality and style of preservation of S. sinuosus on a single surface and the few distinct characteristics preserved within this relatively indistinct fossil also provides the necessary data required to define a taphonomic gradient for this fossil. Armed with this information, structures which have been problematic in the past can now be confidently identified as S. sinuosus based on morphological criteria. This suggests that the original organism that produced this fossil was a widespread and abundant component of the Ediacaran ecosystem.

Tubular specimens belonging to Hyolithellus from silty dolostones of the basal Aftenstjernesø Formation of North Greenland may represent the first occurrence of this widespread Cambrian fossil in life position. A high proportion of preserved specimens are oriented normal to bedding with the tapering end of the tube down. Occasional undulations in the growth of the tubes indicate that the animal actively adjusted its growth to achieve a vertical orientation in relation to the sediment surface. Increasing thickness of the tube wall towards the tapering end shifted the center of mass downwards and resulted in greater stability in the sediment. The tube remained open at both ends throughout ontogeny; it was most likely secreted by an annelid-grade animal which pumped water into the sediment through the tube. Hyolithellus and similar tubular fossils from the Lower Cambrian probably represent stem group annelids.

A costal and a peripheral bone from the Early Cretaceous (Valanginian, ca. 135 Ma) Rosablanca Formation, Zapatoca town, Colombia are described. These specimens represent the earliest record of podocnemidoid turtles. Evolutionary and paleogeographical implications are also discussed.

The Mediterranean area is the locus of a variety of deep-sea chemosynthetic environments that have been exploited by bivalves of the family Solemyidae during Cenozoic to present time. Large solemyids represented by the Solemya doderleini group were widely distributed in Neogene deep-sea reducing habitats, including cold vent hydrocarbon sites. Based upon the diagnostic structure of the ligament, Solemya doderleini (Mayer), 1861 and S. subquadrata (Foresti), 1879 are moved to the genus Acharax Dall, 1908. After the Messinian Salinity Crisis Acharax doderleini re-colonized deep-sea sulphide environments up to the Pliocene at least. At present, Acharax occurs in similar settings in the adjacent eastern Atlantic Ocean. Thus far, large solemyids are not documented from the present deep Mediterranean Sea in spite of a vast number of seep and reducing habitats with chemosynthetic biota, especially concentrated in its Eastern basin. Promisingly, however, a single live juvenile specimen of Solemyidae has been recently found at bathyal depth associated with a pockmark in the Nile Deep Sea Fan.

The family Remingtonocetidae is a basal family of Eocene cetaceans only known from near shore marine environments of India and Pakistan. We describe a new skull for Remingtonocetus harudiensis which elucidates the anatomy and functional morphology of the head and provides new details on cranial cavity and nasopharyngeal region. We suggest that Remingtonocetus was an ambush predator that hunted from a perch on the ocean floor, and that hearing was its most important sense. We speculate that the greatly elongated rostrum is an adaptation for water retention because these are some of the earliest whales living in seawater.

New shell microstructure data for the Triassic pectinid Pleuronectites reinforce shell morphological data suggesting that its family Pectinidae was derived from the superfamily Aviculopectinoidea and not from the Pernopectinidae-Entolioidesidae-Entoliidae clade. This would make the superfamily Pectinoidea, as defined by recent authors, polyphyletic. This would also imply that alivincular-alate ligaments evolved independently in the Pernopectinidae-Entolioidesidae-Entolidae and Pectinidae clades.

New finds of Hyolitha in the Devonian of Bolivia consist of the hyolithid Bolithes crasquinae new genus and species, which is the first well-preserved hyolithid from strata of this age in the region. In addition, specimens of the orthothecids Bolitheca steinmanni (Knod, 1908) and Neobactrotheca pharetra Marek and Isaacson, 1992 serve to increase knowledge concerning the range of morphologic variability within those taxa. Incompletely preserved hyoliths include Hyolithes sp. indet.? which would be the first definitive representative of that genus from South America. Two polyclaviculate hyolithid opercula, and an unusually large hyolithid conch are left in open nomenclature. The large conch is noteworthy because of signs of failed predation, making this only the second hyolithid on record on which the effects of predation can be recognized, and the first from the Devonian of South America. Hyolithes dorbignyi Kozlowski, 1923 is transferred to ‘Hyolithes’ owing to poor preservation.

Laocoetis piserai n. sp. (Hexactinellida, Porifera) from the mid-Cretaceous (i.e., Albian–Cenomanian) of James Ross Island is the first record of a fossil sponge from Antarctica. This new occurrence of a formerly widespread genus was restricted to relatively deep waters on the margins of an active volcanic arc. Its occurrence in Antarctica is further evidence that the genus Laocoetis underwent a dramatic reduction in its geographic range through the Cenozoic. The only living species of the genus at the present day is Laocoetis perion from Madagascar.

The taxonomy and phylogenetic position of the hadrosaurid dinosaur Barsboldia sicinskii is revised. This species is rediagnosed based on the unique combination of iliac central plate with depth/length ratio less than 0.8 and sacral vertebrae with distally ‘clubbed’ neural spines at least four times higher than their centra. A maximum parsimony analysis of 47 hadrosauroid (39 hadrosaurid) species does not support the purported lambeosaurine affinities of B. sicinskii, but recovers this form as a basal saurolophine hadrosaurid based on unambiguous synapomorphies of the ilium. This result increases the diversity of saurolophine taxa in Asia, a continent with a hadrosaurid fossil record so far dominated by lambeosaurines. Finally, several vertebral and iliac characters previously regarded as diagnostic of Lambeosaurinae are discussed and shown to be uninformative from a taxonomic or phylogenetic standpoint.

The Tenebrionoidea is among the most diverse group of beetles, but its fossil record is rare. A definitive oldest tenebrionoid beetle, Wuhua jurassica new genus new species, is described from the Middle Jurassic of Daohugou, China. It is tentatively placed as Family incertae sedis, and distinguished from others of Tenebrionoidea by the unusual combination of following characters: body convex; head strongly deflexed, not received into prothorax; antennae filiform; pygidium absent; tarsi simple and tarsal claws pectinate. This discovery extends the time of origin of Tenebrionoidea to the Middle Jurassic. Furthermore, the record of Mesozoic tenebrionoid beetles are summarized and discussed.

Melittosphex burmensis (Melittosphecidae) is an important apoid fossil from middle Cretaceous (~100 Ma) amber from Myanmar (Burma). Melittosphex exhibits a combination of wasp and bee features making it an important transitional form linking bees with crabronid wasps. The presence of branched hairs suggests that it was a pollen-collector and many aspects of the morphology suggest that it is more closely related to bees than to any fossil or extant group of wasps. Here we report additional morphological information on Melittosphex burmensis. This specimen remains the earliest body-fossil evidence that pollen-collecting Apoidea (bees) were present approximately 20 million years after the origin of the eudicots (~120 Ma), the major angiosperm lineage with extensive reliance on bee pollination.

The Cretaceous Huitrín Formation in west-central Argentina records the final connection of the Neuquén Basin to the Pacific Ocean. This formation is comprised of a variety of continental to marginal-marine sediments deposited behind an Andean volcanic arc under warm, arid paleoclimatic conditions. Here we focus on a bivalve fauna from carbonate ramp deposits within the Barremian La Tosca Member of the Huitrín Formation. This fauna is very abundant and widely distributed within the basin but, surprisingly, it has not yet been studied in detail. In addition, paleoenvironmental affinities remain unresolved, with the fauna variously interpreted as having freshwater, brackish, and marine affinities. We studied the fauna's taxonomy and paleoecology based on more than 500 specimens collected at ten fossil localities in combination with new field observations. The bivalve assemblage was recorded from middle to outer carbonate ramp deposits and is composed of five taxa of marine affinity: Phelopteria huitriniana n. sp., Isognomon cf. I. nanus (Behrendsen), Placunopsis? pichi n. sp., Anthonya jarai n. sp., and Argenticyprina mulensis n. gen. n. sp.; the first three may be regarded as eurytopic and/or opportunistic. Reduced diversity, low evenness, overall small size (length <4 cm), thin shells, eurytopic or opportunistic life strategies, and high endemism point to a restricted marine setting for the La Tosca Member. The most important limiting factors likely were low primary productivity and fluctuating salinity and temperature, as conditions inferred for the unit include high evaporation rates combined with low continental runoff and reduced rainfall. Thick evaporite deposits below and above La Tosca Member and thin intercalated gypsum beds support a restricted, hypersaline setting.

The early astogeny of specimens representing the bryozoan genera Dekayia, Parvohallopora, Heterotrypa, and Homotrypella follows the same pattern documented in other Ordovician trepostomes. After larval settlement and metamorphosis, typically three primary, periancestrular, autozooids bud distally from the founder zooid, the ancestrula, with secondary zooids budding from the primaries, tertiary zooids from the secondaries, and so on. Progressive lateral displacement of buds, through backbudding, eventually produces a subcircular ancestrular disk. Significant intergeneric differences in this basic pattern do not appear to exist. Intrageneric variability in budding pattern occurs during colony development. That variability might have resulted from any or all of the following sources: within-genus plasticity, the development of multiple ancestrulae, or environmental variation. The basic pattern of three primary buds developed from individual ancestrulae has been recognized in other trepostomes, some cyclostomes, and two suborders of cryptostomes. Cladistically, the trait must be considered polyphyletic until more is known about the number of primary buds in the remaining bryozoan suborders. Ancestrular dimensions are statistically similar across genera except between the smaller Dekayia and larger Parvohallopora, but ancestrular sizes in all four Dillsboro genera are consistent with the inference that they possessed a polyembryonic lecithotrophic larval type.

The majority of Changhsingian orthotetid brachiopod species from the Southern Alps were described by the end of the nineteenth century, but were then neglected by subsequent authors who proposed further new species, giving rise to great taxonomical confusion. An examination of type-specimens and newly collected material permits the consideration of Orthothetina ladina (Stache, 1878) and Ombonia tirolensis (Stache, 1878), type-species of Ombonia, as the only valid species and describe Teserina nerii as a new genus and species. The former two species are mostly located within a short stratigraphic interval, which is a few centimetres thick, limited by the trigger and peak of the end-Permian mass extinction. Teserina nerii n. gen. n. sp. occurs 2–3 m above the extinction peak and represents one of the last Permian rhynchonelliform brachiopod holdovers in the Southern Alps.

The evolutionary history of the major boring-bivalve superfamily Pholadoidea remains unclear. Opertochasma somaensis n. sp., preserved in situ in fossilized wood from upper Kimmeridgian to lower Tithonian strata within the Upper Jurassic shallow marine Nakanosawa Formation, northeast Japan, is described. This new species represents one of the oldest body fossils of pholadoidean boring-bivalves and the first fossil record from the Jurassic in the circum-Pacific regions. The authochthonous occurrence in fossilized wood, the presence of microscopic file-like sculpture on the anterior shell slope, the short clavate burrow, and other shell features demonstrate that O. somaensis n. sp. was a filter-feeding, obligate wood-borer with anterior-boring locomotion, and also that the complex shell morphology unique to Pholadoidea was established by the Late Jurassic. The documentation of the new species and taxonomic review on the Jurassic species previously described, show that the superfamily Pholadoidea was widely distributed along the Northern Hemisphere middle latitudes in the latest Jurassic. The Pholadoidea likely evolved by exploiting woody substrata which had become abundant during the Late Jurassic with floral diversification in the middle latitudes. It is notable that the xylophagous mode of life, referable to modern Teredinidae and Xylophagaidae, was most probably established in the Jurassic and provided an important background for the establishment of chemosynthesis-based, sunken wood-associated communities.

The fossil record of the family Falconidae is poor and fragmentary. Extinct representatives from South America include the late early Miocene (Santacrucian) Thegornis musculosus and Thegornis debilis. Both species were originally described as Falconidae and afterwards moved to Accipitridae Circinae or Buteoninae. The analysis of a very well preserved and complete specimen of T. musculosus with similar stratigraphic and geographic provenances of the type material (lower levels of Santa Cruz Formation, coast of Patagonia, Argentina) corroborates the validity of the genus and its falconid affinities. The skull and postcranial morphology exhibit strong resemblances with the open-savannah inhabiting Herpetotheres and the forest-dwelling Micrastur (Herpetotherinae) but differ substantially from Falconinae (Falconini plus Caracarini). Detailed comparisons with a broad arrange of falconiform taxa in a cladistic framework, confirm its phylogenetic placement within the Herpetotherinae and sister to H. cachinnans. The ecotonal margins produced by the vanishing of humid forests that developed during changes in Patagonian plant communities throughout early Neogene times are hypothesized as a plausible scenario to understand the evolution of this basal clade of falcons.