Yuknessia Walcott, 1919 recently was transferred from the green algae to the Phylum Hemichordata on the basis of new details observed for the type species, Y. simplex, from the Burgess Shale Formation (Cambrian Stage 5) of British Columbia. This has prompted reexamination of material attributed to Yuknessia from various Cambrian localities in South China. Findings preclude both a Yuknessia and a hemichordate affinity for all of the Chinese study material, and most of this material is formally transferred to Fuxianospira Chen and Zhou, 1997, a taxon common in the Chengjiang biota. Comparable material from the Cambrian Marjum, Wheeler, and Burgess Shale formations of North America is also assigned to Fuxianospira, and this reassignment expands both the paleogeographic and stratigraphic range of this taxon. All aspects of the study specimens, including details obtained from scanning electron microscopy, are consistent with an algal affinity, as proposed in the original descriptions of the Chinese material.

The Lower Devonian (Lochkovian) hexactinellid sponge Talacastospongia minima new genus new species is reported from the lower beds of the Talacasto Formation in the Argentine Precordillera. It represents the first Devonian sponge from South America and the best record in the paleobiogeographic context of the Malvinokaffric Realm, otherwise virtually devoid of spiculate sponges. This discovery provides some tentative insights on the age and oldest record of the Family Pileolitidae. The paleogeographical context for this new finding shows a high latitude setting with a notable scarcity of hexactinellid sponges recorded to date in Devonian Malvinokaffric basins, and the absence of calcareous spiculate sponges (heteractinids) and hypercalcified sponges (stromatoporoids, sphinctozoans).

The early Cambrian (Terreneuvian, Stage 2) tommotiid Kulparina rostrata Conway Morris and Bengtson in Bengtson et al., 1990 is revised. The pyramidal sclerites of K. rostrata are shown to be bilaterally symmetrical and homologues of the symmetrical S1 sclerites of Paterimitra pyramidalis Laurie, 1986. The scleritome of K. rostrata is also shown to include flattened asymmetrical sclerites that were originally described under the name Eccentrotheca guano Bengtson in Bengtson et al., 1990 and which correspond to the L-sclerites of Paterimitra. A modified tubular scleritome and a sessile filter-feeding mode of life is envisaged for Kulparina rostrata.

Exceptionally preserved specimens of the Cambrian stem-group brachiopod Mickwitzia occidens Walcott, 1908 are described in detail from the Indian Springs Lagerstätte in Nevada, USA. Shell structure and preserved mantle setae from these specimens reveal a variable diagenetic (taphonomic) history and provide insight into the phylogenetic position of mickwitziids. Morphologic and morphometric comparison to M. monilifera (Linnarsson, 1869) from Sweden and M. muralensis Walcott, 1913 from British Columbia, Canada reveals clear species-level distinctions. Scanning electron microscopic analysis allows revision of the generic diagnosis. The Mickwitzia shell is characterized by the presence of inwardly pointing phosphatic cones and tangential setae-bearing tubes. The inwardly pointing cone structures are not consistent with setal bearing structures as previously thought, but rather represent endopunctae-like structures. Acrotretid-like shell structures and shell-penetrating setae in M. occidens strengthen the previously proposed close relationship between stem-group brachiopods and tommotiids, a group of small shelly fossils.

The bryozoan fauna from the South American Cenozoic is poorly known. The study of new material collected in the Monte León Formation (early Miocene), gave us the opportunity to describe four new species: Valdemunitella canui n. sp., Foveolaria praecursor n. sp., Neothoa reptans n. sp., and Calyptotheca santacruzana n. sp. Two of them (V. canui and C. santacruzana) were first recorded by F. Canu and interpreted as recent species from the Australian bryozoan fauna, but are herein described as new species. The stratigraphic range of Otionella parvula (Canu, 1904) is extended to the early Miocene. The present study emphasizes the close relationships between the South American Neogene bryozoan faunas and those of other Gondwanan sub-continents such as New Zealand and Australia.

This paper describes a new genus Liaous, with L. shaiwensis He and Chen n. gen. n. sp. as the type species, from the Xinyuan Formation of Anisian age in Ziyun, southern Guizhou, China. The phylogenetic tree revealed by the parsimony analysis shows that Liaous is closely allied to both Mentzelia Quenstedt, 1871 and Paramentzelia Xu, 1978 of the subfamily Mentzeliinae. A new classification scheme for the Spiriferinoidea is also proposed based on a phylogenetic tree of the superfamily indicated by parsimony analysis. The Spiriferinoidea includes three families and nine subfamilies. Three new subfamilies—Madoinae He and Chen, new subfam., Qinghaispiriferininae He and Chen, new subfam., and Triadispirinae He and Chen, new subfam. are proposed. Liaous shaiwensis He and Chen n. gen. n. sp. is found in the Posidonia wengensis-Liaous shaiwensis (P-L) paleocommunity, which is dominated by r-strategists (i.e., organisms defined by a fauna with a high dominance and small body sizes) and has a low diversity and high dominance. The P-L paleocommunity therefore has little similarity to its coeval communities from the Anisian Stage of South China and instead it appears more similar to the Lower Triassic shelly faunas in community structures. This paleocommunity is interpreted to have inhabited a relatively deep, low-energy, dysaerobic offshore basin/slope setting with the influence of episodic storms.

Modern computer-aided techniques foster the availability and quality of 3D visualization and reconstruction of extinct and extant species. Moreover, animated sequences of locomotion and other movements find their way into motion pictures and documentary films, but also gain attraction in science. While movement analysis is well advanced in vertebrates, particularly in mammals and birds, analyses in arthropods, with their much higher variability regarding general anatomy and size, are still in their infancies and restricted to a few laboratory species. These restrictions and deficient understanding of terrestrial arthropod locomotion in general impedes sensible reconstruction of movements in those species that are not directly observable (e.g., extinct and cryptic species). Since shortcomings like over-simplified approaches to simulate arthropod locomotion became obvious recently, in this review we provide insight into physical, morphological, physiological, behavioral, and ecological constraints, which are essential for sensible reconstructions of terrestrial arthropod locomotion. Such concerted consideration along with sensible evaluations of stability and efficiency requirements can pave the way to realistic assessment of leg coordination and body dynamics.

The Middle Ordovician (Darriwilian) Winneshiek Lagerstätte of northeast Iowa is preserved in a meteorite crater. Besides conodonts, the fossils are dominated by arthropods, particularly eurypterids and phyllocarids. Here we describe the bivalved forms, which include at least seven different taxa. The small phyllocarid Ceratiocaris winneshiekensis, new species, is the most abundant; it is the oldest representative of the Ceratiocarididae. A single incomplete abdomen and telson bearing furcal rami is reminiscent of notostracan branchiopods but its affinities are unknown. Decoracaris hildebrandi, new genus and species, is a rare form with a shield that extends anteriorly into a swollen horn and reaches lengths of 9 cm: it may represent a thylacocephalan crustacean but this cannot be confirmed without soft parts. Iosuperstes collisionis, new genus and species, is represented by suboval valves 10–25 mm long: its affinities are unknown. A probable leperditicopid, which ranges in length from 8 to 18 mm, is commonly preserved in a ‘butterflied’ configuration. It does not preserve the scars and sinuses characteristic of three-dimensionally preserved leperditicopids from elsewhere. Finally the fauna includes at least three ostracods, including a palaeocope with a granular surface and relief similar to Lomatopisthia, and a smooth ?podocope. The Winneshiek fauna differs from those of other Ordovician Lagerstätten from restricted settings such as Airport Cove and William Lake in Manitoba (Katian) where, apart from ostracods, bivalved arthropods are absent, and Silurian examples such as Brandon Bridge (Telychian), which lacks eurypterids, and the Williamsville Member of the Bertie Formation (Pridoli) where conodont assemblages are absent.

Phyllocarids of the Waukesha Biota were systematically and taphonomically evaluated. Three Ceratiocaris species are present in the biota: C. macroura Collette and Rudkin, 2010; C. papilio Salter in Murchison, 1859; and C. pusilla Matthew, 1889. Specimens range in completeness from nearly complete, including the cephalic to caudal regions, to isolated telsons and furcae. Evidence of Salter's position is present in only three specimens. Relatively complete specimens are interpreted to represent corpses, rather than molts; whereas specimens including only the pleon and caudal region, or caudal region, and specimens with evidence of Salter's position likely represent exuviae. Specimens are preserved essentially as compression fossils exhibiting two types of preserved cuticle: brown inner cuticle, which tends to be impressed over the topography of bedding planes on which specimens are preserved, and blue-gray phosphatized cuticle exhibiting sub-millimeter scale relief. Cuticle phosphatization likely occurred during early diagenesis. The presence of characteristic near-shore species and C. pusilla, only known from turbidite facies, interpreted to possibly represent a marine trough, suggests that the Waukesha phyllocarid assemblage might represent a transported assemblage, rather than a biota, or that C. pusilla from the Jones Creek Formation was transported basinward in sediment gravity flows.

The distribution of all recognized biotic elements was mapped on five extensive surfaces of the Middle Triassic Guanling Formation exposed in quarries near Luoping, Yunnan Province, China. A 0.5 m² grid was overlain on the surfaces, and all recognizable fossils were located by placing them in one of nine quadrants within the grid. A total of 240 m² were mapped, and each specimen observed was recorded as one of 15 categories, subsequently grouped as pelagic, benthic, and other (bone, trace fossils, algae). The pelagic component, fish, thylacocephalans, and mysidaceans, dominated all layers. The benthic component was sparse on all surfaces; epifaunal, vagrant organisms were the dominant forms, suggesting that the substrate was unsuitable for infaunal and sessile epifaunal organisms. Shrimp and bivalves dominated the benthic organisms. Two of the surfaces were overwhelmingly dominated by mysidaceans, and one was dominated by thylacocephalans, suggesting that their remains documented periodic mass kills of swarming, pelagic organisms. Scanning electron microscope analysis of the bedding surfaces revealed nothing remarkable about the sediment, suggesting that the cause of death of the organisms was likely due to an event within the water column, possibly an algae bloom, not recorded in the sediment record.

The first mastotermitid termite from Africa is described and figured from wing fragments recovered from the early Miocene (22–21 Ma) deposits of the Mush Valley, Amhara Region, central Ethiopia. Mastotermes aethiopicus new species is the second fossil termite recorded from Africa and expands the known paleo-distribution of the genus from tropical North America and Europe into northeastern Africa during the Miocene. Mastotermes aethiopicus is distinguished from the living M. darwiniensis Froggatt and other Neogene species of the genus, and comments are provided regarding the occurrence of this genus in the tropical fauna of Miocene Ethiopia.

The fossil record of Australasian Formicidae is extremely sparse. It currently comprises two ants in the subfamilies Ponerinae and Dolichoderinae from Plio/Pleistocene strata in Victoria, Australia, 14 as-yet undescribed ants from Cape York amber, and one ant in the subfamily Amblyoponinae from the early Miocene Foulden Maar in southern New Zealand. Here, we report on a diverse myrmecofauna preserved as compression fossils from Foulden Maar and describe Amblyoponinae gen. et sp. indet., Rhytidoponera waipiata n. sp., Rhytidoponera gibsoni n. sp., Myrmecorhynchus novaeseelandiae n. sp., and Austroponera schneideri n. sp. Further isolated wings are designated as Formicidae sp. A, B, and C, the former resembling a member of subfamily Dolichoderinae. Fossils of Austroponera and Myrmecorhynchus are reported for the first time, whereas Rhytidoponera waipiata n. sp. and R. gibsoni n. sp. are the first Southern Hemisphere fossil records of this genus.

The fossil taxa from Foulden Maar establish the subfamilies Ectatomminae, Formicinae, Ponerinae and, possibly, Dolichoderinae in the Australasian region in the early Miocene and provide evidence that the few native ants in the extant New Zealand fauna are the surviving remnant of taxonomically different, possibly more diverse, warm-temperate to subtropical myrmecofauna.

Fossil Scydmaeninae beetles are exceptionally poorly known and those described usually lack important details to reliably analyze their phylogenetic relationships with extant taxa. Baltostigus n. gen. is the first extinct ant-like stone beetle taxon unambiguously assigned to the tribe Mastigini. It includes B. antennatus n. sp. (the type species of Baltostigus) and B. horribilis n. sp., from the lower to middle Eocene amber of Poland and Lithuania, respectively. Results of a phylogenetic analysis comprising morphological characters of all extant and extinct genera of the supertribe Mastigitae strongly support the placement of Baltostigus as a sister group to all remaining Mastigini. The new genus shows character states not known in any extant Mastigini: fully developed hind wings, prominent humeral calli, deep elytral punctures partly arranged in longitudinal rows and symmetrical aedeagal parameres. These features suggest that Mastigini might have evolved from forms morphologically similar to small-bodied extant Clidicini of the ‘Leptochromus lineage.’

A new crinoid association reported from the Kope Formation (Katian, Ordovician) of northern Kentucky and southwestern Ohio changes the model for facies distribution of crinoids along an Ordovician onshoreoffshore depth gradient. Glyptocrinus nodosus n. sp., Plicodendrocrinus casei (Meek, 1871), Cincinnaticrinus varibrachialis (Warn and Strimple, 1977), and Ectenocrinus simplex (Hall, 1847) are reported from a suspensionfeeding assemblage with 26 taxa. This assemblage developed above an argillaceous packstone with most of the fossils preserved in shale. The fauna was comprised principally of secondary epifaunally tiered suspension feeders, deposit feeders, and predators. This is the first reported occurrence of Glyptocrinus Hall, 1847 and Plicodendrocrinus Brower, 1995 from the Kope Formation (lower Cincinnatian), and Glyptocrinus is represented by a new species, G. nodosus. Also, this is the first report of pinnulate camerate crinoids from the deep-water facies of the Kope Formation. Thus, deep-water Cincinnatian crinoid assemblages were comprised of disparids, cladids, and camerates; and the assemblage was characterized by a variety of filtration fan types for acquisition of resources.

The Cretaceous Period (145–66 Ma) consisted of several oceanic anoxic events (120–80 Ma), stimulated by global greenhouse effects. The Oceanic Anoxic Event 2 (OAE2) occurred worldwide from the late Cenomanian to the early-middle Turonian, causing a significant faunal turnover, mostly in marine biota, pushing some species to the brink of extinction. Some organisms also underwent morphological changes, including reduction in size. This anoxic event drove other changes—e.g., in habitats or strategy of life. We show that stalkless crinoids (comatulids) from the Turonian of Poland adapted to unfavorable environmental conditions by reducing their body size. Furthermore, at the moment when environmental factors became favorable again, these crinoids regained their regular (pre-event) size. This phenomenon likely illustrates the so-called dwarfing mode of the Lilliput effect.

A tooth recovered from the middle Miocene Choptank Formation (Chesapeake Group) of Maryland is identified as a new cynarctin borophagine (Canidae: Borophaginae: Cynarctina), here called Cynarctus wangi n. sp. The tooth, identified as a right upper second molar, represents the first carnivoran material reported from the Choptank Formation and part of a limited record of borophagine canids from eastern North America. As ?Cynarctus marylandica (Berry, 1938), another cynarctin borophagine from the older Calvert Formation, is known only from lower dentition, its generic affinities are uncertain. However, features of this new material are compared to features of ?C. marylandica through occlusal relationships, allowing for referral to a distinct species. Even so, the Choptank Formation material still offers two possible scenarios regarding its identification. In one, its geographic and stratigraphic provenance could imply that it belongs to ?C. marylandica. If this were correct, then the generic placement of ?C. marylandica would be correct and the taxon would be more derived than some other Cynarctus species in regard to hypocarnivory, and less derived than others. The second possibility, and the one believed to be most probable, is that a distinct cynarctin borophagine is present in the Chesapeake Group in strata younger than the type specimen of ?C. marylandica. This new borophagine canid expands the sparse fossil record of this group in northeastern North America and furthers our knowledge of the fossil record of terrestrial taxa in this region.