Phylogenetic relationships within the neogastropod family Nassariidae are poorly understood as are relationships between the Nassariidae and other fossil and extant buccinid taxa. The poor resolution of nassariid and buccinoidean relationships is due to: 1) the complex distribution among these gastropods of characters commonly used in classification; 2) a number of Mesozoic and Paleogene genera whose relationships to extant buccinoidean lineages are poorly constrained; and 3) a lack of previous efforts to address these problems on a rigorous, phylogenetic basis.

The results of a phylogenetic analysis of nassariid genera did not decisively support the monophyly of the family. The buccinid subfamily Photinae was an extant sister group to the Nassariinae in a phylogenetic analysis of extant taxa and on many cladograms from an analysis combining fossil and extant taxa. In addition, Buccitriton (representing the Paleogene Tritiaria group) was a sister taxon to the Nassariinae in all analyses in which it was included, regardless of the identity of the extant nassariine sister group. This suggests that the photines, which likely arose from a Tritiaria ancestor, are the closest living relatives to the Nassariinae. Many Paleogene fossil “buccinoid” taxa appear to be more distantly related to the Nassariinae and possibly to the rest of the nassariids as well. Stratigraphic range data combined with the results of this study suggest that the Nassariinae diversified rapidly in the early Miocene and achieved a cosmopolitan distribution early in their history. A largely Indo-Pacific subclade was consistently deeply-nested within the Nassariinae, suggesting that nassariines invaded the Indo-Pacific region most recently. The timing of this invasion is difficult to estimate but had occurred by the end of the Miocene. Further analyses using molecular sequence data, relative stratigraphic position, or focusing in more detail on the Paleogene taxa are required to resolve the identity of the sister group to the Nassariinae with greater confidence.

Newly discovered fossils from Eocene rocks of the Quimper Sandstone, Washington, USA, constitute the first reported occurrence of the albuneid genus Lophomastix Benedict, 1904, in the fossil record. Lophomastix and the closely related genus Blepharipoda Randall, 1839, are thought to be basal taxa within the decapod family Albuneidae Stimpson, 1858, based upon possession of primitive trichobranch gill structures. The occurrence of Lophomastix antiqua new species in Eocene deposits indicates that the genus is at least as old as the more derived genus, Albunea Weber, 1795, as would be expected for the basal taxon within the family. Based upon examination of type material, Blepharipoda brucei Rathbun, 1926, is herein removed from that genus and placed within the Paguroidea as Pagurus brucei (Rathbun, 1926) new combination.

The attachment of a small edrioasteroid to the nonperiproctal surface of a small specimen of the pleurocystitid rhombiferan Amecystis has implications for the life posture of pleurocystitids and indicates that Amecystis was epifaunal. Articulation of the preserved portions of both thecae indicates that the edrioasteroid and Amecystis were alive at or very near the time of burial and that the edrioasteroid used the Amecystis theca as an attachment surface. Other examples of edricasteroids attaching to live organisms are known suggesting that an edrioasteroid attached to a live rhombiferan is not highly unusual. The position of the edrioasteroid on the rhombiferan suggests that Amecystis was oriented with the anal side down in life and that this pleurocystitid was fully epifaunal.

The poorly known type species of Lingulella, Lingula davisii M'Coy, 1851b, is redefined from new material collected from the type locality and horizon (Upper Cambrian, North Wales). Lingulella is similar to Obolus and to Ungula in its musculature mantle canals, and pseudointerareas, but has a thinner shell and irregular pits over its internal surface, concentrated in the visceral areas. A dissolution method that can facilitate the study of lingulate brachiopods preserved in clastic lithologies is described, and its wider adoption is recommended in order to reveal diagnostic morphological characters.

Twenty-three species of trilobites are recognized in the lower Mississippian Caballero and Lake Valley Formations of southern New Mexico. Species exhibit a segregation into shelf and off-shelf faunas, and can be subdivided into three distinct stratigraphic faunas. Species found in the Caballero Formation are similar to those found in the Chouteau Formation of Missouri. A second fauna, comprising species found in the Alamogordo, Nunn, and Tierra Blanca Members of the Lake Valley Formation, is correlated with the Fern Glen and Burlington Formations of Missouri. The third fauna found in the Arcente and Dona Ana Members of the Lake Valley Formation is correlated with the Warsaw and Salem Formations of the United States midcontinent region.

Named species from the Kinderhookian Caballero Formation include: Dixiphopyge armata (Vogdes, 1891), Comptonaspis swallowi (Shumard, 1855), Brachymetopus indianwellsensis new species, Ameropiltonia perplexa new species, Griffithidella caballeroensis new species, and Kollarcephalus granatai new genus and new species. Named species from the Lake Valley Formation include: Pudoproetus fernglenensis (Weller, 1909), Breviphillipsia semiteretis Hessler, 1963, Griffithidella doris (Hall 1860), Phillibole planucauda (Brezinski, 1998), Piltonia carlakertisae new species, Australosutura llanoensis Brezinski, 1998, Thigriffides triangulatus new species, Thigriffides? alamogordoensis new species, Namuropyge newmexicoensis new species, Nunnaspis stitti new genus and new species, Hesslerides arcentensis new genus and new species, as well as an unnamed species of Proetides Hessler, 1962, Namuropyge Brezinski, 1988, and Thigriffides Hessler, 1965.

The Mississippian blastoid Pentremites Say, 1820, has three different types of summit structures. Type 1 summits are characterized by long slender plates and are present in upper Meramecian and lower-upper Chesterian beds occurring from Iowa to Alabama. Type 2 summits consist of a massive pyramidal summit composed of large toothlike plates. They occur in lower and middle Chesterian deposits located from Illinois to Kentucky. Type 3 summit structures differ greatly from Types 1 and 2, generally consisting of six to seven rectangular plates arched over each side of individual spiracles. They have been found only in middle Chesterian sediments of Kentucky. In all three types of summit structures, the plates covering the anal spiracle are the most numerous and have a specialized arrangement of plates. Some anal spiracles are covered by alternating small spikelike plates, while others display a distinct anal sac or moundlike structure consisting of many small polygonal plates. Type 2 summits have many similarities with Type 1, and may have been derived from it. Type 3 summits, however, are radically different in type of plates and in their arrangement; their origin is not known. Type 3 summits are very common in the middle Chesterian.

Development of the ventral muscle field has been studied in 12 genera of clitambonitidine brachiopods: Eremotoechia, Clitambonites, Vellamo, Pahlenella, Lacunarites, Oslogonites, Gonambonites, Estlandia, Anchigonites, Kullervo, Antigonambonites, and Raunites. The last two have a pseudospondylium instead of spondylium, which links them to polytoechiids. The spondylium of the studied genera is not derived from convergent dental plates, but develops from the free plate in the early phase of morphogenesis. The early growth stages of spondylium triplex and simplex are identical. The hypothetical ancestor of clitambonitidines with spondylium was presumably a protorthid-like brachiopod probably of the mid-Cambrian age. On the contrary, polytoechiids, as well as Antigonambonites and Raunites, may have been derived from a late Cambrian billingsellid with dental plates. The polyphyly of clitambonitidines follows from development of their ventral muscle field.

Small coprolite-bearing borings occur in the stem of the filicalean tree fern Itopsidema vancleaveii Daugherty from the Chinle Formation of Late Triassic Age (Carnian Stage) in Petrified Forest National Park, Arizona. These borings are restricted to parenchyma within the leaf petioles and among the adventitious roots of the root mantle. Although they are not lined by wound tissue, some of the borings in the leaf petioles contain small discontinuous masses of wound-tissue at a few places along some of the walls, indicating that the plant was alive when it was attacked. Coprolites within the borings generally are small (mostly about 40–50 μm in diameter and 85–100 μm in length) and oval in longitudinal section and round to weakly hexagonal in transverse section; they consist of very small particles of unidentifiable plant matter. Although the weakly hexagonal coprolites are similar to those produced by termites but they are an order of magnitude smaller. Furthermore, the borings are much smaller than those produced by known extant termites. It is likely that oribatid mites produced the coprolite-bearing borings and coprolites. This occurrence is significant because it bridges the Late Permian to Early Jurassic gap in the geologic record of endophagous mites and also contributes new data on arthropod activity during the Late Triassic in southwestern North America.

New portunoid fossils from southern Argentina and from the west coast of North America permit the reevaluation of the generic and family relationships within the Portunoidea Rafinesque, 1815. It has previously been suggested that the Portunidae and the Geryonidae Colosi, 1923, are closely related families (Manning and Holthuis, 1989). The new fossils suggest that the Geryonidae may in fact be derived from a portunid progenitor, Proterocarcinus Feldmann, Casadío, Chirino-Gálvez, and Aguirre Urreta, 1995, through a process of peramorphosis in which juveniles of the geryonid species Chaceon peruvianus (d'Orbigny, 1842) resemble adults of Proterocarcinus latus (Glaessner, 1933). Examination of several genera within the portunid subfamily Polybiinae Ortmann, 1893, including Imaizumila Karasawa, 1993; Megokkos new genus; Minohellenus Karasawa, 1990; Pororaria Glaessner, 1980; Portunites Bell, 1858; and Proterocarcinus, suggests that the subfamily had an amphitropical distribution early in its history. New taxa reported here include Megokkos new genus and Portunites nodosus new species. New combinations include Chaceon peruvianus (d'Orbigny, 1842), Imaizumila araucana (Philippi, 1887), Megokkos alaskensis (Rathbun, 1926), Megokkos hexagonalis (Nagao, 1932), Megokkos macrospinus (Schweitzer, Feldmann, Tucker, and Berglund, 2000), Minohellenus triangulum (Rathbun, 1926), and Proterocarcinus latus (Glaessner, 1933).

The Mississippian ammonoid genus Dzhaprakoceras Popov, 1965, well known in the eastern hemisphere, is reported from the Delle Member of the Deseret Limestone at Flux and Lakeside Mountains, Tooele County, Utah. This is the first report of the genus in western North America. The ammonoids, D. gordoni n. sp. and D. djaprakense (Librovitch, 1927) occur with mehli—Lower texanus Zone conodonts indicating a middle Osagean (earliest Viséan) age.

An examination of Devonian through Pennsylvanian postibullinid edrioasteroids indicates the presence of two clades in the monophyletic subfamily Postibullinae, new subfamily. Postibulla is characterized by the presence of a posterior oral protuberance and a cover plate pattern with three primary plates and includes Postibulla legrandensis, P. lukei, P. keslingi, P. neglecta, and P. alabamaensis new species. Parapostibulla new genus is characterized by double biserial cover plates, the lack of the posterior oral protuberance, and an unusual hydro-gonopore, and includes Parapostibulla hybolopus (Fraunfelter and Utgaard, 1970), P. murphyi new species and Parapostibulla species A. Additional poorly-preserved edrioasteroids are illustrated from the Missourian and Virgilian of Kansas and Iowa that are the youngest known from North America.

Despite its atypical thecal plate pattern, Lagynocystis pyramidalis (Jaekel, 1918) (Middle Ordovician, Northern Gondwanaland) is composed of normally positioned marginal plates on the left side of the theca, whereas those on the right side are shortened or missing in comparison with marginal plates of other ankyroids. The only somatic on the lower thecal surface is the CS plate. The abnormally long distal aulacophore, reduced theca, and internal ctenoid organ are interpreted as adaptations to deep water, dysaerobic environmental conditions. Ctenoid organ morphology is re-evaluated and is interpreted to have both feeding and respiratory functions. Loss of plates relative to a presumed ancestor similar to Barrandeocarpus has resulted in torsion that places somatic platelets, originally on the superior face, onto the inferior face and in contact with both CS and M′3 plates.

Paleocene spatangoids are unknown from the Antilles, apart from evidence from trace fossils. The peak of spatangoid diversity was the Eocene. Jamaican Oligo-Miocene spatangoids have a relatively low diversity compared with that of the Antillean region. Plio-Pleistocene spatangoids are poorly known from the Antilles (four genera), in contrast to the Oligo-Miocene (16 genera) and Holocene (17 genera). The depauperate Paleocene and Plio-Pleistocene spatangoid faunas are probably in part artifacts of incomplete sampling, facies-related absences, outcrop area effects and the relative brevity of these stratigraphic intervals.

To the large echinoid fauna of the Swanswick Formation (Middle-Upper Eocene) of Jamaica is added the schizasterid Aguayoaster schickleri new species. This is the first record of this genus outside Cuba; it is distinctly more elongate than all other known specimens of this genus. The schizasterid Caribbaster loveni (Cotteau, 1875) is recorded from the Swanswick Formation for the first time, the youngest occurrence of this genus in Jamaica. The coeval Claremont Formation has not previously yielded spatangoid echinoids; the brissid Eupatagus cf. antillarum (Cotteau) from a new locality is the first spatangoid known from a lagoonal unit of the White Limestone Group.

An investigation of the morphology and astogenetic pattern of isolated specimens of two species of Paraclimacograptus permits an assessment of the phylogenetic relationships of this genus. Forty-two specimens previously assigned to Paraclimacograptus innotatus ssp. isolated from turbiditic limestone from the Southern Urals of Russia (Cystograptus vesiculous Zone) and limestone concretions from the Canadian Arctic (Coronograptus cyphus Zone) were examined using the method of infrared video microscopy. Paraclimacograptus has a Pattern H astogeny and is therefore a member of the family Normalograptidae. At least three species can be distinguished using biometric criteria, P. innotatus, P. exquisitus, and P. obesus. Rhabdosomal characteristics of Paraclimacograptus indicate that it is phylogenetically related to early species of the genus Neodiplograptus. The point of divergence of the proximal thecae is defined by the interfingering of fuselli of markedly different widths. This suggests that fuselli were not necessarily secreted at a constant rate. In addition, this pattern of fusellar interfingering is here regarded as more consistent with a pterobranch mode of secretion than with a model of growth under an enveloping extrathecal mantle.

The Hanford Brook Formation, one of the classic Cambrian units of Avalonian North America, contains at least eight species of endemic trilobites, including Berabichia milleri Westrop n. sp., that are assigned to seven genera. The vertical succession of faunas is far more complex than has been recognized previously, with each member containing a lithofacies-specific assemblage. These are, in ascending order: a bradoriid-linguloid Association without trilobites in the nearshore St. Martin's Member, a Protolenus Association in dysaerobic siltstones and sandstones of the Somerset Street Member, and a Kingaspidoides-Berabichia Association in hummocky cross-stratified sandstones of the Long Island Member that overlie a parasequence boundary at Hanford Brook. Due to the breakdown of biogeographic barriers in the late Early Cambrian, two new species-based zones, the Protolenus elegans and Kingaspidoides cf. obliquoculatus zones, share trilobite genera with the Tissafinian Stage of Morocco. This generic similarity has been the basis for correlation of this upper Lower Cambrian interval on the Avalon continent with the West Gondwanan lowest Middle Cambrian. However, the clear facies control on the occurrence of genera in the Hanford Brook Formation and the presence of an abrupt faunal break and unconformity at the base of the Tissafinian in Morocco makes this correlation questionable. The Hanford Brook Formation may represent a late Early Cambrian interval unknown in Gondwana. Sequence-stratigraphic criteria even raise the possibility that the Protolenus Association is the biofacies equivalent of Callavia broeggeri Zone faunas of the Brigus Formation of Newfoundland, Nova Scotia and Massachusetts.

The cyrtospiriferid brachiopod genus Tenticospirifer Tien, 1938, is revised based on restudy of the type species from the Frasnian (Late Devonian) of the Russian Platform. As revised the genus includes cyrtospiriferid species with pyramidal ventral valves, catacline ventral interareas, a narrow delthyrium, few sinal plications, and lack a median dorsal septum and pseudodeltidium. All species retained in the genus are of Givetian and Frasnian age. All Famennian age species described from South China and North America are rejected from the genus. It appears that Tenticospirifer evolved during the early Givetian in western Europe and remained endemic to that region during the remainder of the Givetian. Successive migrations of Tenticospirifer from eastern Laurussia to North America, then to South China and possibly Australia, coincided with middle and late Frasnian eustatic sea level rises, respectively. The North American species Spirifera cyrtinaformis Hall and Whitfield, 1872, and related species identified as Tenticospirifer by North American workers, are reassigned to Conispirifer Lyashenko, 1985. Its immigration to and widespread dispersal in carbonate platforms of western Laurussia, northern Gondwana and tropical island arcs (?) coincided with a major late Frasnian eustatic sea level rise. The new family Conispiriferidae is proposed with Conispirifer Lyashenko, 1985, selected as the type genus. The new family also includes the new genus Pyramidaspirifer with Platyrachella alta Fenton and Fenton, 1924, proposed as the type species. The affinity of the new family remains uncertain pending restudy of key genera currently included in the Superfamily Cyrtospiriferoidea. Available data from the Devonian brachiopod literature indicate that species of Pyramidaspirifer are restricted to late Frasnian deposits of central and western North America.

A new late Osagean (Lower Mississippian) crinoid fauna is described from the Muldraugh Member of the Borden Formation of central Kentucky. The Muldraugh Member records a mixed carbonate-siliciclastic tempestite-dominated ramp environment. This is the first report of late Osagean crinoids from this depositional setting on the eastern side of the Eastern Interior Basin of the midcontinental United States. The Muldraugh crinoid fauna contains 66 species and is dominated by advanced cladids. This fauna has similarities to other late Osagean faunas but is distinctive both in species abundance and rank order abundance of species. Eight new species are described from this fauna, including Camptocrinus nudus, Paradichocrinus ramus, Poteriocrinites horowitzi, Parascytalocrinus pentagonus, Abrotocrinus debrae, Abrotocrinus springeri, Worthenocrinus hardinensis, and Mespilocrinus myllos.

Sand dollars in the Monophorasteridae Lahille, 1896, form an important part of the South American Cenozoic echinoid fauna. Re-examination of type and other material adds significantly to our knowledge of the morphology and taxonomy of the family, and shows that besides Monophoraster darwini (Desor, 1847), M. duboisi (Cotteau, 1884), Amplaster coloniensis Martínez, 1984, and A. alatus Rossi de Garcia and Levy, 1989, there is a new species, A. ellipticus. We also show that Karlaster Marchesini Santos, 1958, is not a monophorasterid as once thought. A phylogenetic analysis of 24 characters assessed from all species of Monophoraster Lambert and Thiéry, 1921, and Amplaster Martínez, 1984, along with genera of the Mellitidae Stefanini, 1912, produced a single most parsimonious tree. The analysis demonstrates monophyly of mellitids and monophorasterids, and that Iheringiella Berg, 1898, should be excluded from the latter. Although both Monophoraster Lambert and Thiéry, 1921, and Amplaster Martínez, 1984, retain many features of an ancestor in common with the Mellitidae Stefanini, 1912, they also exhibit bizarre morphologies quite different from those of mellitids. The study has also resulted in a clearer picture of the biogeography and biostratigraphy of the Monophorasteridae, and their great significance in the evolution of lunulate sand dollars in the Americas.

The multielement conodont genus, Anticostiodus new genus, is described based on discrete elements from the Lower Silurian (early Aeronian) Gun River Formation of Anticosti Island, Quebec. The apparatus includes pectiniform Pa, Pb, Pc and Pd elements and ramiform M, Sa, Sb and Sc elements. Two new species are included under the new genus, Anticostiodus fahraeusi (type species) and Anticostiodus boltoni. Both species occur near the base of Distomodus staurognathoides Zone and in an open subtidal environment.

The lower part of the Shinarish Formation of Djebel Sinjar, northwest Iraq, yields an ammonite assemblage of Upper Campanian age dominated by heteromorph taxa: Nostoceras (Nostoceras) ellipticum new species, N. (N.)(?) budanyi Foldyna and Vašiček, 1977, N. (N.) cf. hyatti Stephenson, 1941, Exiteloceras(?) etequense Lewy, 1969, Didymoceras sp., unassigned nostoceratid fragments, Solenoceras reesidei Stephenson, 1941, and Lewyites oronensis (Lewy, 1969), together with the normally coiled Hauericeras (Gardeniceras) sp. Several of the species present also occur in the lower part of the Mishash Formation in Israel, in the Gulf Coast region of the United States, and as rarities in the U.S. Western Interior. All occurrences are compatible with an Upper Campanian attribution.