Small gastropod opercula have been found at one locality each in the Desmoinesian and Virgilian of north-central Texas. Because of their general shape and concentric growth, these opercula are placed within the Neritacea. One form probably is the operculum of Trachydomia. Four other forms, two of which are morphologically quite similar but from different ages, probably belong with Naticopsis sensu lato.

We described a Late Cretaceous fish fauna from the Campanian-age Blufftown Formation in western Georgia (Case and Schwimmer, 1988), including 15 selachian taxa and 8 osteichthyans; however, at that time no chimaeras had been found in the region. A well-preserved specimen of Ischyodus bifurcatus Case, 1978, was subsequently collected from the same general locality described in the above study, but in the immediately superjacent Cusseta Formation. This is a note of the new occurrence of this fish and a summary of its known geographic and stratigraphic distribution (Appendix).

Angiosperms first appeared in the fossil record as pollen during the Valanginian–Hauterivian; they spread out of the tropics in the Aptian and Albian, and radiated in the Late Cretaceous. Despite these general patterns, details of the taxonomic, geographic, and ecological evolution of Cretaceous angiosperms are relatively poorly known because only a handful of Early and mid-Cretaceous macrofloras have been reported. This is the first detailed report of a fossil leaf flora from the Cedar Mountain Formation from the mid-Cretaceous of the Western Interior. We describe a flora that is overwhelmingly dominated by angiosperms (152 of 153 identified specimens are angiosperms) from the Albian–Cenomanian transition that is preserved in a clay- and carbonate-rich, lacustrine mudstone from the uppermost Cedar Mountain Formation of Emery County, Utah. We recognize 18 leaf morphotypes, all of which are dicotyledonous angiosperms. The majority of the Cedar Mountain morphotypes have taxonomic affinities with forms of similar age described from the Atlantic and Gulf coastal plains and other localities from the Western Interior. From this, we infer that a relatively diverse angiosperm flora grew along the margins of a small pond on the coastal plain. Palynological preparations of the fossil matrix were barren; however, previous studies of other facies within the formation showed that both conifers and ferns were important components of the regional vegetation during Cedar Mountain time. The effective absence of conifers and ferns in this macroflora and low leaf mass per area values among the angiosperms measured suggests that even at the Early–Late Cretaceous transition, angiosperms had come to dominate some sites, particularly those that were disturbed or seasonally ephemeral, where fast-growth or seasonal deciduousness would have been favored.

Since the genus Retrotapes was erected, some authors have favored or opposed its validity, or argued about the assignment of the extant species R. exalbidus and R. lenticularis to Retrotapes. Some authors synonymized Retrotapes with the Miocene genus Frigichione, and others with the extant genus Eurhomalea to which most of the species that belong to Retrotapes were previously assigned. In the present contribution, a phylogenetic analysis of the genus is performed to test these controversies. In addition, a systematic revision of the Chilean species of the genus is performed to complete the analysis of Retrotapes taxa from Patagonia and Antarctica started by previous authors. This study demonstrates that Retrotapes is a monophyletic genus, which is not closely related to Frigichione or Eurhomalea. Instead, Retrotapes is closely related to some Austral taxa from Kerguelen Island (Paleomarcia), New Zealand (Atamarcia), and Australia (Katelysia), a relationship previously unknown. Besides, the extant species R. lenticularis and R. exalbidus belong to Retrotapes and were recovered as part of a clade closely related to the type species of the genus, R. ninfasiensis (Miocene, Patagonia). Retrotapes is reported in Chile beginning in the late Eocene, where it was represented by R. difficilis n. comb., which is a taxon that resembles some Eocene species of the same genus from Antarctica. In the late Oligocene–early Miocene, it was represented by R. navidadis and later in the Pliocene by three species: the fossil R. fuenzalidae and the two extant ones.

Pleurojulid millipedes, known since the turn of the last century to be relatively abundant in the Westphalian D (Carboniferous: Pennsylvanian) Gaskohl of Nýřany, Czech Republic, are here also identified as an important component of the Pennsylvanian (Westphalian D) Mazon Creek millipede fauna preserved in ironstone nodules. Pleurojulids reach lengths approaching 10 cm, have as many as 69 body segments, medium-sized heads, and large ocellaria with upwards of 40 ocelli. Pleurojulids have previously been interpreted as having either a juliform-like or a colobognathan-like trunk-ring architecture. In order to distinguish between these two hypotheses, almost all pleurojulid specimens in museum collections were surveyed to document the deformation pattern of exoskeletal elements to aid in reconstruction of the trunk-ring architecture. The Nýřany specimens are completely flattened while the Mazon Creek specimens retain a degree of three-dimensionality. In order to assess how trunk-ring architecture controls patterns of deformation, a variety of extant millipedes were experimentally compressed. The distribution of exoskeletal elements in pleurojulid fossils was most similar to that seen in compressed extant polyzoniid millipedes. Based on the available evidence, pleurojulid trunk-ring architecture is reconstructed as semicircular in cross section, consisting of arched diplotergites, free pleurites firmly articulated to the lateral margins of the tergites and held in a near horizontal position, and free sternites. Pleurojulida are hypothesized to be basal helminthomorph, the sister group to Colobognatha, though inclusion in Helminthomorpha is equivocal. The taxonomy of previously described pleurojulid millipedes from Nýřany is revised and newly recognized specimens from Mazon Creek specimens are described. Two genera are recognized within the new order Pleurojulida: Pleurojulus and Isojulus. Two species of Pleurojulus are recognized: P. biornatus and P. levis. Pleurojulus aculeatus and P. pinguis are synonymized with P. levis. Only one species of Isojulus, I. constans, is recognized with I. setipes, I. marginatus synonymized with it along with Pleurojulus longipes and P. falcifer.

The specimen NHMUK 39514 comprises the cranial remains of a plesiosaur found on the Dorset coast during the middle of the ninetieth century. It was partially described and figured by Owen and variously attributed to Plesiosaurus rostratus (Owen) and to Plesiosaurus conybeari (Sollas). NHMUK 39514 is a partial braincase and mandible. It differs from all other Early Jurassic plesiosaurs known including the two species to which it was originally referred. The mandible presents several pliosauromorph characters but the specimen is identified as Plesiosauria indet. because it has several plesiomorphic characters in its braincase anatomy. This assignment will prevent the introduction of a possible chimera in future phylogenetical analyses and paleobiogeographic reconstructions.

Two specimens of the cornute Phyllocystis crassimarginata Thoral, 1935 from the Lower Ordovician of Southern Montagne Noire (Languedoc, France) showing abnormal numbers of marginal plates are described. the first one (UM 310) is characterized by the insertion of one extra plate between the fourth right marginal and the zygal plate Z. Comparison with a new, undescribed Tremadoc boot-shaped cornute suggests that 1) the extra plate of UM 310 is equivalent to M4, and 2) the three right marginals located between M1 and Z in “normal” specimens of Phyllocystis can be identified as M2, Mc, and M3. Plate configurations of the right thecal margin are thus identical in “normal” Phyllocystis, chauvelicystids, and cothurnocystids. This result indicates that Phyllocystis is probably more closely related to these two clades than to scotiaecystids. Consequently, the identification of the four marginals forming the left thecal margin of Phyllocystis (M′2, M′3, M′5, and M′5) is deduced from a comparison with the cothurnocystid plate pattern. the second abnormal specimen of P. crassimarginata (R64546) is characterized by the loss of M′3. It confirms that reduction in the number of marginals is a general trend in boot-shaped cornutes.

Two bivalved arthropods of the family Sunellidae Huo, 1965 are described from the Lower Cambrian Helinpu Formation of southwestern China: Sunella cf. shensiensis Huo, 1965 and Combinivalvula chengjiangensis Hou, 1987. Both taxa preserve soft anatomies, described here for the first time, including a pair of lateral eyes and a possible median eye, a trunk carrying flaplike appendages, and a simple gut with caeca. The family Sunellidae includes three genera: Sunella Huo, Combinivalvula Hou, and Jinningella Huo and Shu. In contrast to most other Cambrian arthropods with a larger bivalved carapace, especially those from the Burgess Shale–type deposits, sunellids lack a limbless abdomen protruding posteriorly beyond the carapace. This, coupled with a combination of a number of snared features (e.g., the presence of cardinal spines and distinctive anterodorsal sulcus, elongated valves, and median eye), appears to support sunellids as a clade. The distinctive anterodorsal sulcus extending from the anterodorsal corner to the anteromedian part of the carapace is regarded as an autapomorphy for this clade. Sunellids resemble Isoxys Walcott, 1890 to which they may be closely related; both possess a bivalved, elongated carapace with cardinal spines that almost entirely covers the body. However, neither cephalic appendages nor proximal portions of trunk limbs are visible in sunellids, and thus, their systematic position remains uncertain.

Pharciceras Hyatt, 1884 is the diagnostic ammonoid of the late middle Givetian Stage of the Middle Devonian Series. It occurs in the Rhenish Massif in Germany, the Montagne Noire in southern France, and in equivalent strata in the Anti-Atlas in southern Morocco. Verified North American occurrences of Pharciceras are confined to the New York succession, where the appearance of the ancestral species P. amplexum (Hall, 1886) in the Upper Tully Limestone represents an important and well-established biostratigraphic datum within the Taghanic onlap interval (see Aboussalam and Becker, 2001 for discussion). In this note we describe a second, distinctly younger, North American species, Pharciceras barnetti n. sp., from the New Albany Shale in eastcentral Kentucky that provides new evidence on the Taghanic onlap interval (Upper Tully/Geneseo Sequence of Baird and Brett, 2003) in the central Appalachian Basin. This occurrence is particularly significant because of its association with conodonts that provide a basis for refined correlations between the central Appalachian Basin and the Taghanic onlap succession in New York.

Stromatoporoids are the principal framebuilding organisms in the patch reef that is part of the reservoir of the Normandville field. The reef is 10 m thick and 1.5 km2 in area and demonstrates that stromatoporoids retained their ability to build reefal edifices into Famennian time despite the biotic crisis at the close of Frasnian time. The fauna is dominated by labechiids but includes three non-labechiid species. The most abundant species is Stylostroma sinense (Dong) but Labechia palliseri Stearn is also common. Both these species are highly variable and are described in terms of multiple phases that occur in a single skeleton. The other species described are Clathrostroma cf. C. jukkense Yavorsky, Gerronostroma sp. (a columnar species), and Stromatopora sp. The fauna belongs in Famennian/Strunian assemblage 2 as defined by Stearn et al. (1988).

Actinopterygian vertebral centra are more common in the Pennsylvanian and Early Permian of central North America than was previously known. The oldest record dates from the Early Carboniferous of England. Stratigraphic occurrence, co-occurring vertebrate fauna, histology, and external morphology contradict a previous interpretation as centra of “holosteans.” The centra are assigned here to Palaeoniscoidea indet. Besides centra in haplolepids, these are the only known actinopterygian centra from the Paleozoic. The so-called caudal centra in Pygopterus are the bases of hypurals.

Fragments of a ceratopsian dinosaur from the Maastrichtian Hell Creek Formation, Garfield County, Montana, are unlike any known ceratopsian. Diagnostic features include a low, rounded nasal boss, an especially deep rostral-premaxillary pit, and paired choanae. The snout is elongate. The new taxon, Ugrosaurus olsoni, is referred to the Ceratopsidae.

The non-marine Lower Cretaceous ostracod genus Kegelina new genus (Cypridoidea, Cyprideidae) is known from South America (Bahia state, eastern Brazil), West Africa (Gabon and ‘Congo'), and North America (Montana, Idaho and Wyoming, U.S.A.). It comprises five species: Kegelina anomala (Peck, 1941) new combination, Kegelina armata (Krömmelbein, 1962) new combination, Kegelina bisculpturata (Wicher, 1959) new combination, Kegelina depressa (Moura, 1972) new combination, and Kegelina kegeli (Wicher, 1959) new combination, all of which having formerly been described as representatives of Cypridea Bosquet, 1852. The closer relationships of Kegelina new genus among the Cyprideidae Martin, 1940 are discussed. Other potential species of Kegelina n. gen. are presumed to occur in northeastern China and Europe but remain to be examined.

Most species of the middle and late Hettangian psiloceratid genus Sunrisites are endemic to the eastern Pacific, where they are common members of ammonoid assemblages. the Taseko Lakes map area in British Columbia yields diverse and well-preserved Sunrisites faunas which are formally described here for the first time. Three new species are recognized, S. brimblecombei, S. chilcotinensis, and S. senililevis. the new species require an extension of the morphological range of the genus to include forms that become moderately involute at large shell diameters. Signs of sexual dimorphism are apparent within all three new species of Sunrisites. This work extends the stratigraphic range of Sunrisites to include the latest Hettangian Rursicostatum Zone in North America. The distribution of Sunrisites suggests that the Hispanic Corridor, which linked the western Tethyan Ocean and the eastern Pacific, may have been open during the Hettangian. Furthermore, occurrences of the genus constrain the Hettangian position of several allochthonous terranes to the northeastern Pacific.

A new genus and species of Asteroidea (Echinodermata), Embolaster graffhami, Embolasteridae, n. fam., is described from the Upper Ordovician Bromide Formation of Oklahoma. Embolaster is important in part because of the presence of two similar ossicles on each interbrachial plane in the axillary position; only a single axillary is recognized in most Paleozoic asteroids. the axillary traditionally has been considered to be a part of the marginal series, although marginals are almost always paired. the two ossicles are interpreted as axillaries and the homologues of an ancestral proximal marginal pair. the odontophore, which lies distal to the mouth angle pair of most asteroids, tentatively is the homologue of the proximal axillary.

Embolaster also is important because of the presence of an ossicular series between the ambulacrals and the putative adambulacrals. An extra ossicular series in this position is known from taxa traditionally assigned to the ophiuroids; however, other characters of Embolaster indicate asteroid affinities for this genus. the two ossicles lateral to and aligned with the ambulacrals in Embolaster are interpreted as homologous with the similarly arranged radial virgal series of somasteroids, although specific ossicular homologies are problematic.

A part of the mouth frame structure of Embolaster is exposed, although it is tiny and therefore difficult to interpret. the mouth frame arrangement is reminiscent of those of somasteroids, with small, narrow circumorals and apparent buccal podial basins directed toward the mouth opening. Many of the striking characters of Embolaster probably are plesiomorphic; apomorphies are difficult to ascertain.

The fluid flow through the complex hydrospires of the spiraculate blastoid Pentremites rusticus was analyzed using the first high-resolution three-dimensional digital image (and animation) of the hydrospires taken from a serially sectioned specimen. Measurements of the cross-sectional areas within the hydrospires, in conjunction with the Principle of Continuity, were used to infer the relative water velocity throughout the structures. Even though the calyx narrows adorally, the hydrospires expand in size, keeping pace with the increasing volume of water that entered through the hydrospire pores. Thus, the water maintained a relatively constant velocity within the hydrospire canals, 3.4 to 4.5 times the incurrent velocity. The spiracular openings are sufficiently large that no substantial increase in the exit velocity of the seawater would have been achieved unless the spiracular cover plates were used to reduce the size of the spiracular openings, which we infer was probably the case. The three-dimensional images underscore the fact that the two hydrospires that lie under each ambulacrum do not share the same spiracle and are not connected. Thus, we here redefine the term “hydrospire set” to refer to the pair of hydrospires that are connected. A number of anomalous accessory pores and canals were identified in the digital images. This initial study is based on a single specimen, and thus we were unable to determine the full range of variation present in Pentremites rusticus. Nonetheless, the digital image and the application of the Principle of Continuity offer new insights into the form and function of these remarkable respiratory structures.

Titanopterans are spectacular, giant, predatory insects mainly known from the Triassic, but they are known from a few localities in Central Asia (including European Russia) and Australia. The Nampo Group is a nonmarine sequence, located on the southwestern Korean Peninsula, the age of which has remained controversial, due to lack of proper age-constraining fossils. Here, we report a new titanopteran Magnatitan jongheoni n. gen. n. sp. from the Amisan Formation, Nampo Group. The division of the radius anterior and radius posterior beyond the distal half of the fossil wing is a characteristic of the family Paratitanidae. This is the first discovery of a titanopteran fossil outside of Central Asia and Australia, suggesting a possible circum-Tethys oceanic distribution. Given the possibly widespread distribution of titanopterans, this group might have played a critical role as giant predatory insects in Triassic terrestrial ecology. Because titanopterans have never been found beyond the Triassic-Jurassic boundary, the occurrence of a titanopteran corroborates the Triassic age of the Nampo Group.

UUID: http://zoobank.org/10177029-0044-424f-9816-e3fb057cfe85

An early form of eurypterids (Chelicerata), Archopterus anjiensis n. gen. n. sp., is described from the uppermost Ordovician Wenchang Formation of Anji County, Zhejiang Province, South China. It is the earliest record of eurypterids in China and likely the oldest representative of the Adelophthalmidae. The species, represented by a single specimen, is diagnosed by a ventrally preserved prosoma with a parabolic carapace, Hughmilleria-type prosomal appendages, a short vase-shaped metastoma, and a three-segmented type A (female) genital appendage. The specimen is preserved, together with diverse sponges, graptolites and occasional nautiloids, in a 10 m thick shale of marine deep-water setting. This finding extends the stratigraphic range of adelophthalmids from the previously recorded early Silurian into the Late Ordovician (some 10 million years older) and supports an earlier cryptic phase of eurypterid evolution in Gondwana.

UUID: http://zoobank.org/a2d090e5-1a15-40b6-8e2a-dda45b01e94d

Priacanthids are a small family of percomorph fishes comprising fewer than 20 extant species currently assigned to four genera. One of these, Pristigenys, was established by Louis Agassiz (1835) to include the Eocene species Pristigenys substriata from Monte Bolca, and is usually regarded as a subjective senior synonym of Pseudopriacanthus. Consequently, Pristigenys currently comprises five extant species plus the fossil Pristigenys substriata. The osteology of the type species of this genus, however, is poorly known, and this makes it difficult to provide an adequate comprehensive definition of the taxonomy of the whole family. Pristigenys substriata is redescribed in detail based on five well-preserved articulated skeletons. Pristigenys substriata can be easily distinguished from other priacanthids based on its unique combination of characters. Morphological analysis of the fossil specimens reveals that there is substantial evidence to justify recognition of both Pristigenys and Pseudopriacanthus as valid genera, with extant species previously assigned to Pristigenys now referred to Pseudopriacanthus. Within the Priacanthidae, Pristigenys and Pseudopriacanthus form sister taxa and this pair can be considered as the sister-group to all remaining extant priacanthid genera (Cookeolus + [Heteropriacanthus+Priacanthus]).