Research on fossil decapod crustaceans has accelerated since the publication of the Treatise on Invertebrate Paleontology dealing with the group. Increase in the number of paleontologists studying the Decapoda, exploration of previously poorly known areas, and major advances in neontological research has made it possible to transform fossil decapods from the category of interesting and beautiful fossils to that of useful subjects for research in paleoecology and paleobiogeography. Classification of fossil decapods has become more refined as new taxa have been recognized in the fossil record and as neontological approaches to classification, including larval anatomy, comparative spermatology, morphology of novel structures, and molecular analysis, are considered in conjunction with fossil evidence. This combination of approaches can now be used to develop testable hypotheses regarding phylogeny of the group. Detailed observational data on living and fossil biotic associations has been coupled with experimental studies to enhance our understanding of organic interactions as well as to understand the biasing factors of taphonomy that affect the fossil record of organisms with organic exoskeletons. Broad studies of distribution of decapods in time and space are now possible, owing to the increase in number of fossil sites studied and taxa described. We can define patterns of biogeographic distribution that can be tested against patterns derived from the study of more commonly preserved organisms, such as the mollusks. As this research continues, it is anticipated that studies of paleobiogeography and paleoecology will increasingly rely on data from the fossil record of the decapod Crustacea.

A brachiopod fauna from the upper part of the Nakazato Formation, southern Kitakami Mountains, northeast Japan, is nearly similar to the fauna from the top of the Yikewusu Formation (upper Eifelian) in the Zhusilenghaierhan region, western Inner Mongolia. The Nakazato fauna is systematically described and consists of 10 species and four indeterminate species assigned to 14 genera. Two new species are designated Maoristrophia subquadrata and Malurostrophia sugiyamai. Brachiopods from the upper part of the Nakazato Formation suggest that the age of the fauna is likely Eifelian.

A brachiopod fauna of 16 species belonging to 11 genera and three genera and species indeterminate from the middle and upper parts of the Juripu Formation in the Yarlung-Zangbo (Indus-Tsangbo) Suture zone (=Yarlung-Zangbo River zone), southern Tibet, is described and figured for the first time. A new species, Taeniothaerus zhongbaensis, is described. The fauna is comparable with that in the Kalabagh Member of the Wargal Formation of the Salt Range, Pakistan, and is considered to be most likely Capitanian (late Guadalupian/Middle Permian) to Wuchiapingian (early Lopingian/early Late Permian) in age, as indicated by the majority of the brachiopod species and by being constrained by an underlying fusulinacean fauna (Parafusulina Zone) and an overlying ammonite fauna (Cyclolobus fauna).

Myophorellid bivalves (Trigonioida, Myophorellacea) with conspicuously tuberculate shells are abundant in Lower Cretaceous rocks of the Neuquén Basin represented by the Gondwanian genus Steinmanella Crickmay, 1930. Publications concerning Neuquén trigonioids deal only with taxonomy, and until now the sedimentary environments of the Steinmanella bearing facies have not been interpreted. The present study analyzes morphology, taxonomy, stratigraphy, and paleobiology of Steinmanella species collected from five sections of the Lower Member of the Agrio Formation, including the type locality. Two species are differentiated: Steinmanella pehuenmapuensis (Leanza, 1998) from the lower part of the member (Pseudofavrella angulatiformis Zone) and Steinmanella transitoria (Steinmann, 1881) from the middle and upper part of the member (Holcoptychites neuquensis, Hoplitocrioceras gentilii, and Weavericeras vacaensis Zones).

Specimens of both species have been recorded in intermediate to high-energy shoreface and low-energy offshore deposits. The inferred paleoecologic model is that Steinmanella lived semi-infaunally and burrowed on sandy substrates in the shoreface and on muddy substrates in the offshore. Colonization of low-energy subenvironments in the offshore probably occurred during increased sea-floor oxygenation and reduced net sedimentation or brief omission periods.

We used 24 fossil and Recent species to construct character states of both composite and exemplar taxa for phylogenetic analyses of Neogene genera and subgenera of the Corbulidae from tropical America. All characters were conchologic and two matrices, which differed in the manner that commarginal-rib characters were coded, were analyzed using branch and bound searches and maximum parsimony. Character polarity was determined using Corbula sensu strictu as an outgroup. These analyses produced a limited number of robust and well-resolved cladograms that require only one ghost lineage. Such stable results indicate a high level of congruency among characters, and demonstrate that conchologic data sets can yield highly resolved cladograms.

Tropical American corbulids are not monophyletic, and include two major clades. Crown groups within these clades are endemic, and all genera endemic to tropical America first appear in the Miocene. In fact, generic diversity and body size peak in the upper Miocene of the Caribbean/western Atlantic. Range restrictions and extinctions of large-bodied genera from both corbulid clades contribute to a post-Miocene decline in body size in this region. The eastern Pacific does not experience a similar decline in diversity and body size. Diversity and morphologic trends in Caribbean corbulids coincide with regional environmental changes, in particular decreases in seasonality and productivity. Except for the extinction of Bothrocorbula, however, corbulid extinctions apparently predate faunal turnover reported for other molluscs.

Associated with these extinctions, we found evidence of geographic range restriction, but not range shifts, in corbulid genera, indicating that the geologic development of environmental refugia contributed more to survival than eurytopy. Large-bodied genera of the southern Caribbean Gatunian Province (Tenuicorbula, Panamicorbula, and Hexacorbula) became restricted to the eastern Pacific. Range restriction to this high productivity refugium (i.e., paciphilic genera), rather than origination of new taxa, produced several corbulid genera now endemic to the region. Large-bodied genera from the Caloosahatchian Province of the southeastern U.S. (Bothrocorbula and Bicorbula), however, underwent global extinction. These subtropical and warm temperate taxa are presumably more eurytopic than their tropical counterparts, but do not exhibit range shifts in response to Neogene environmental change.

A new genus, Anomalosaepia, and four new species, A. alleni, A. mariettani, A. vernei, and A. andreanae (Sepiida: Belosaepidae) from the Castle Hayne Limestone of southeastern North Carolina are described. Belosaepia jeletzkyi from the Cook Mountain Formation of Louisiana is assigned to Anomalosaepia. All new and referred species differ from Belosaepia in having strongly laterally curved ventral plates, guard-like sheaths without external rugosities, and spine tips with a slit-like aperture.

Diagnoses based upon preservable carapace features are provided for the brachyuran families Carpiliidae, Palaeoxanthopsidae new family, Pseudoziidae, and Zanthopsidae, newly raised to family status. In order to make family and generic level assignments, characters of the dorsal carapace can be used successfully as proxies for soft-part morphology that is not commonly or never preserved in fossils. The identification of carpiliids and pseudoziids in the fossil record yields critical information about the time of divergence of these groups, no later than Eocene, and the relationships between those two families, the Eriphiidae, and the extinct Zanthopsidae. Because the timing of divergence of at least two xanthoid families is now known more accurately, more constrained phylogenetic studies can result. The Eocene to Recent Carpiliidae is restricted to one extant genus and five fossil genera. The Eocene to Recent Pseudoziidae contains the fossil genera Archaeozius new genus, Priabonocarcinus, and Santeezanthus as well as several extant genera; one extant genus, Euryozius, also has a fossil record. The Paleocene-Miocene Zanthopsidae embraces five extinct genera including Neoxanthopsis new genus. The new family Palaeoxanthopsidae includes four extinct genera, including Paraverrucoides new genus and Remia new genus and occurs in Maastrichtian-Eocene rocks. New combinations include Archaeozius occidentalis, Harpactoxanthopsis bittneri, Harpactoxanthopsis souverbei, Neozanthopsis bruckmanni, N. carolinensis, N. rathbunae, N. sonthofensis, N. tridentata, Ocalina straeleni, Palaeocarpilius mississippiensis, Palaeocarpilius valrovinensis, Paraverrucoides alabamensis, and Remia africana.

Chen and Yao (1993) described diverse echinoderm communities from Ordovician through Upper Carboniferous rocks in western Yunnan, China—the first monographic treatment of Chinese echinoderms in almost 70 years. This paper is the first in a series of studies re-describing echinoderm taxa from these biogeographically important Paleozoic assemblages. Pentremites globosus Chen and Yao, 1993 is designated as the type species of Sinorbitremites, a new genus of orbitremitid blastoids. Pentremites ovatus Chen and Yao, 1993 is placed in synonymy with Sinorbitremites globosus (Chen and Yao, 1993). Cryptoschisma conicum has been reassigned to Breimeriblastus, a hyperoblastid blastoid.

Two new Neogene South American croakers of the genus Plagioscion (Perciformes, Sciaenidae) from marine sediments, Plagioscion marinus and Plagioscion urumacoensis, are described. These are otoliths from the lower Miocene Castillo, Cantaure and upper Miocene Urumaco Formations of the Neogene Venezuelan basin, respectively. An additional undetermined fossil species of Plagioscion was also collected from the upper Miocene to lower Pliocene Cubagua Formation. Using the function total fish length = 13.7187 + 50.8399 ∗ Ln otolith size, the total length of P. marinus n. sp. is inferred to be from 6.05 to 38.1 cm, and for the specimens of P. urumacoensis n. sp. it is 63.3 cm. The length distribution of the fossil species overlaps the length distribution of the living freshwater species.

A new genus and species of hipposiderid bat is described from an early to middle Miocene cave deposit (AL90 Site, estimated to be between 15 and 20 million years old) at Riversleigh, northwestern Queensland, Australia. Archerops annectens new genus and species is interpreted to be most closely related to species of the Asian genera Coelops and Paracoelops and southeastern Africa's Cloeotis percivali, none of which has a fossil record. The new Australian fossil bat: 1) shares a number of apomorphies with species of Coelops, Paracoelops, and Cloeotis; 2) lacks striking autapomorphies characterizing each of the three extant genera; 3) exhibits few autapomorphies its own; and 4) forms a structural intermediate between plesiomorphic Tertiary hipposiderids (e.g., Brachipposideros species) and the aberrant Coelops, Paracoelops, and Cloeotis species.

Noncalcified thalli, consisting of a narrow main axis with numerous branched hairlike laterals in whorls and a subapical array of undivided clavate laterals, from the Silurian (Llandovery) Brandon Bridge Formation of southeastern Wisconsin, constitute the basis for a new genus and species of dasycladalean alga, Heterocladus waukeshaensis. A relationship within the family Triploporellaceae is indicated by the whorled arrangement of the laterals and the absence of gametophores on mature specimens. A compilation of occurrence data suggests that noncalcified dasyclads, as a whole, were more abundant and diverse during the Ordovician and Silurian than at any other time in their history. The heterocladous thallus architecture of this alga adds to a wide range of morphological variation documented among Ordovician and Silurian dasyclads, the sum of which indicates that Dasycladales underwent a significant evolutionary radiation during the early Paleozoic.

The aquatic palynomorph genus Cobricosphaeridium Harland and Sarjeant, 1970 was described from Holocene deposits of Australia. Restudy of the type material shows that these palynomorphs may represent the eggs of crustaceans, and that earlier attributions to the division Dinoflagellata are unsustainable. The genus Aquadulcum Harland and Sarjeant, 1970, also first described as a dinoflagellate from the Holocene of Australia, is treated as a synonym of Cobricosphaeridium, and the following new combinations are proposed: C. awendae, C. myalupense, C. pikeae, C. serpens, C. yanchepense, C.? ovatum, and C.? vermiculatum. Previous records of the genus are restricted to the Holocene and indicate a freshwater affinity.

Cobricosphaeridium has now been found in Holocene subsurface brackish deposits of Laguna Hinojales in eastern Argentina. This is the first record of this genus from South America and unequivocally extends its ecological range into a brackish environment. Several species are represented, including Cobricosphaeridium hinojalensis new species; and their potential as paleoenvironmental indicators is evaluated.

Amber is a superb medium for the fossilization of delicate organisms. Besides light microscopy techniques for the study of insects in amber, scanning electron microscopy (SEM) in backscattered electron mode (SEM-BSE), low temperature SEM (LTSEM) and also confocal laser scanning microscopy (CLSM) were used to examine microcenosis and particulate plant remains (microdebris). We applied these techniques to such inclusions in amber Álava, northern Spain (Allaian: Early Cretaceous). Confocal microscopy provides a 3D image of partial microcenosis showing bifurcate fungal hyphae. The huge potential of SEM-BSE yields high resolution images, in which the relationship between protozoa and fungal hyphae may be observed and the characterization of further ultrastructural details in flagellates. According to the SEM-BSE images, food and pulsatile vacuoles appear better preserved than mitochondria and lipids in amber-embedded protozoa. A process of protozoan mineralization has led to the deposition of S and Fe in peripheral areas, and the Fe is also present in the core of surrounding fungal hyphae. Application of LTSEM for the study of protozoan inclusions produces images of their exteriors showing many vacuoles. Plant tissues under SEM-BSE show mummified cell walls, while the cytoplasm exhibits a bright appearance and is very rich in Fe and S. SEM in secondary electron mode (SEM-SE) also reveals a microbiota trapped in gas bubbles.

In spite of a long geological record from the Paleozoic Era to the present, most paleontological documentation of multivalved chitons (Mollusca: Polyplacophora) is based on individual, loose plates. Indeed, the tendency of the chitinous girdle in which the eight calcareous plates are articulated to disintegrate usually does not allow their post-mortem association to be observed (e.g., Smith, 1960; Squires and Goedert, 1995; Dell'Angelo et al., 1998).

In recent years, the authors, along with colleagues, have documented the lower Virgilian ammonoid faunas of the Midcontinent and north-central Texas (Boardman et al., 1989, 1994a, 1994b; Work and Boardman, 1995, 1996). Generic diversity for this interval is the highest in any Upper Pennsylvanian succession: at least 18 genera (representing 15 families) have been recovered from the Colony Creek Shale in north-central Texas alone (Boardman et al., 1989). An additional, previously unrecognized ammonoid from the correlative Little Pawnee Shale in southeastern Kansas is described herein as Mapesites chautauquaensis new genus and species. It is a highly original taxon with no obvious close relatives.

Graptolites are the most important biostratigraphic tool in the study of the Silurian of the Argentine Precordillera. Since, however, the graptolites are concentrated primarily in the Lower Llandovery and Ludlow of the region, the ages of parts of some stratigraphic units are poorly known. The recovery of a small Upper Llandovery graptolite assemblage in the lower one-third of the La Chilca Formation of the Talacasto area helps in resolving this problem, and that assemblage is the focus of this study. Brachiopods, trilobites, bivalves, and ostracodes are present in the same stratigraphic intervals, but are less common and less studied and, thus, of less biostratigraphic value.