The coral fauna of the Upper Mississippian (Chesterian) Pitkin Formation was described by Easton (1943) and, more recently, by Webb (1987), who defined two coral faunules. The lower faunule occurs throughout the Pitkin outcrop belt from northeastern Oklahoma to north-central Arkansas. The upper faunule has been recognized only in north-central Arkansas where a higher part of the Pitkin is preserved. Equivalent strata have apparently been removed to the west by the pre-Pennsylvanian regional unconformity that differentially truncates Chesterian strata across the Ozark uplift. Thus the upper faunule is less well known than the lower faunule. The purpose of this note is to describe a new tabulate coral from the upper faunule in Searcy County, Arkansas.

The recent 2014–2017 controlled excavations carried out in quarries of Sverdlovsk and Tyumen regions, Ural and Western Siberia, are contributing to the knowledge of the middle to late Eocene marine fauna from the Turgay Strait, mainly composed of invertebrates and cartilaginous and bony fishes. Here we present a preliminary report of the bony fishes collected during the campaigns carried out in two Eocene Trans-Urals localities. The sediments of these localities were deposited in a large epicontinental marine basin during the middle to late Eocene, when the Turgay Strait connected the Arctic waters to the North and the Peritethys to the South. Most of the bony fish material examined can be assigned to codfishes (Gadiformes) according to morphological comparison with living and fossil taxa. In particular, nearly complete three-dimensionally preserved lower jaws are confidently assigned to the Merlucciidae, whereas isolated vertebrae and bones are referred to as Gadiformes incertae sedis. This report documents the easternmost occurrence of this group of fishes in the northern hemisphere during the early phases of their radiation, revealing their presence into the Turgay Strait before its closure.

Reports of Mississippian polyplacophorans from North America are rare. To date only three species, Gryphochiton parvus (Stevens, 1858) and G. elevatus (Kues, 1978), from the Salem Limestone in Indiana, and Elachychiton juxtaterminus Hoare and Mapes, 1985, from the Imo Formation in Arkansas, have been recognized (Smith and Hoare, 1987). Lobarochiton anomalus (Rowley, 1908), from the Louisiana Limestone in Missouri, is now believed to be Devonian in age. European reports of Lower Carboniferous polyplacophorans are much more common, at least 29 species (Hoare and Smith, 1987). The location of any specimen in the Mississippian of North America becomes significant in filling out the geologic history of this taxonomic group.

A new species of planorbid gastropod, Vorticifex taylori, is described from the Late Miocene (Clarendonian) Truckee Formation at its type area in Churchill County, Nevada. Comparison with younger and older species assigned to Vorticifex indicates a high degree of morphologic variation within the genus as contrasted with relatively conservative intraspecific variation, which may reflect ecologic similarities at discrete times during the development of the Great Basin subprovince of the Basin and Range physiographic province.

Preservation of relict color patterns on fossil nautiloid cephalopods is a relatively rare phenomenon. Reports of this phenomenon as summarized by Kobluck and Mapes (1989, table 2) for the Paleozoic indicate that perhaps as many as 32 genera with coiled, orthoconic, and cyrtoconic conchs have been described with relict color patterns. However, reports of Mesozoic occurrences are limited to only Ophionautilus? in the Jurassic (Shimanski, 1962) and Eutrephoceras in the Cretaceous (Shimanski, 1962; Landman, 1982). Cenozoic reports are limited to Aturia in the Tertiary (Foerste, 1930; Shimanski, 1962; Teichert, 1964) and modern Nautilus (see Saunders and Landman, 1987, for an extensive treatment). The reports on both Mesozoic occurrences are limited to description of external conch morphology, detailed appearance of the color patterns, and the relationship of the remnant color pattern to the conch morphology. Indeed, the specimen discussed herein was originally illustrated by Landman (1982, fig. 8), with a caption indicating the presence of possible color banding. Analysis of this Cretaceous specimen allows comparison to Nautilus and provides a suggestion as to the evolution of certain mature color patterns in coiled cephalopods from the late Mesozoic to Recent.

The genus Bicarinella Rode et al., 2003 was erected for a new hipponicharionid bradoriid species described from the early Cambrian of East Antarctica, characterized by a subtriangular carapace with prominent anterior and posterior lobes developed as two distinctive, sharp ridges (bi = two, carina = ridges). Unfortunately, the name Bicarinella is preoccupied by two different gastropod genera: Bicarinella Waterhouse 1966, a Permian gastropod from New Zealand and Australia, and Bicarinella Akopyan 1976, a gastropod from Late Cretaceous strata of Armenia, Serbia, Romania, Tajikistan, and Egypt (Mennessier, 1994; Banjac, 1998; Pana, 1998). Mennessier (1994) transferred Bicarinella Akopyan, 1976 from its original status as an independent taxon to a subgenus of Pseudomesalia Douvillé 1916, but subsequent workers have continued to consider Bicarinella a valid genus (Pena, 1998; Banjac, 1998). Due to the preoccupation, the bradoriid genus is herein renamed in accordance with the requirement of the International Code of Zoological Nomenclature (1999, article 60). It is also noted here that the one of the two distinct gastropod genera should be renamed. The name Bicarinellata (bi = two, carina = ridges) is proposed as a replacement name for Bicarinella Rode et al., 2003. This name retains the original prefixes to preserve taxonomic stability as much as possible. The type species of Bicarinellata is B. evansi by original designation (Rode et al., 2003).

A new species of Hypolophites (Chondrichthyes, Myliobatiformes) is described from an assemblage of isolated pavement teeth recovered from the Lower Clayton Limestone Unit of the Midway Group (Paleocene) near Malvern, Arkansas. These teeth were collected from several localized lag deposits containing an abundance of chondrichthyan and osteichthyan teeth, invertebrate remains, and trace fossils indicative of a marginal-shallow marine depositional environment. To date, only four additional species of Hypolophites have been reported from Paleocene deposits that occur along the west coast of central-northern Africa and in central New Jersey, USA. The identification of Hypolophites beckeri n. sp. in southwestern Arkansas extends the distribution of this biostratigraphically significant genus ~1,750 km westward into the Mississippi Embayment and Gulf Coastal Plain of the USA. The distribution of Hypolophites species during the Paleocene attests to the uniformity of shallow marine shelves between western Africa and the Atlantic and Gulf Coastal Plains of the USA, as well as myliobatiform diversification following the K/Pg mass extinction event.

UUID: http://zoobank.org/3a1580d1-a2f4-49b6-8170-69a778c49181

The morphology of Argyrotheca lorioli Smirnova, 1972, from the Lower Cretaceous (Berriasian) of Crimea, Ukraine, was reinvestigated using SEM, found to be impunctate, and reassigned as the type species of a new genus Apodosia, new family Apodosiidae, order ?Rhynchonellida. Another micromorphic brachiopod, Spiriferina? oolitica (Moore, 1855) from the Middle Jurassic (Bajocian) Inferior Oolite of Somerset, England, is also reassigned to the new genus.

Reexamination of previously described conulariids has shown that the morphology of steeply pyramidal, generally four-sided conulariid exoskeletons is more complex than was realized by earlier generations of conulariid specialists (e.g., Van Iten, 1992a, 1992b; Jerre, 1994; Van Iten et al., 1996). Much of this complexity is expressed as variation in the anatomy of the corners and midlines (Van Iten, 1992a). In nearly all conulariids, the corners are sulcate, and in some genera (e.g., Archaeoconularia Bouček, 1939 and Pseudoconularia Bouček, 1939) the longitudinal center line, or midline, of the faces also is sulcate or is marked by a straight or zigzagged ridge. In the oldest known conulariid, Baccaconularia Hughes, Gunderson, and Weedon, 2000 (Cambrian: Furongian Series), the midlines are marked by a series of elongate invaginations. Corners and/or midlines of many other conulariids exhibit subtle or pronounced internal thickening (e.g., Van Iten, 1992a; Jerre, 1994). Most such conulariids exhibit one or two sets of longitudinal ridges, or carinae, with a single carina at each corner and/or a single carina or a pair of carinae at each midline. The height of the carinae varies considerably between species, ranging from less than one-fiftieth to over one-half the distance to the center of the exoskeletal cavity. Both corner and midline carinae may be continuous or (less frequently) seriated. Also, the abaxial edge of single midline carinae may have a single crest or (rarely) it may be weakly or strongly bifurcate.

Knowledge on Early Jurassic marine fossil invertebrates from Argentina is very uneven. Particularly, faunas from Chubut Province received less attention and were thought to be poorer than those from the Neuquén Basin. Nevertheless, an updated revision of bivalves shows that some groups, such as the Protobranchia, were relatively more diverse in Chubut than in Neuquén during late Pliensbachian–early Toarcian times. Only four species are known from the southern areas of the Neuquén Basin, while seven species (three of them new) are here described from Chubut, belonging to the families Nuculidae, Nuculanidae, Polidevciidae, and Malletiidae. The new species are: Palaeonucula feruglioi n. sp., Ryderia tehuelchana n. sp., and Phaenodesmia? piatnitzkyi n. sp. The material is well preserved and allows a detailed analysis of their hinge regions and other internal characters. The presence in Chubut of Palaeoneilo? patagonidica (Leanza) is confirmed, which, along with Praesaccella ovum (Sowerby), are the only two species in common with the Neuquén Basin. The new species Ryderia tehuelchana, belonging to a genus that had a wide global distribution between Rhaetian and Toarcian times, but which was known from South America only for upper Triassic deposits, is of special paleobiogeographic interest. These bivalves are restricted to normal marine environments, and due to their detritivorous feeding habits they only live in organic-rich bottoms as very active shallow burrowers.

UUID: http://zoobank.org/41225cf2-b7de-4ff0-ad20-ce0d738799a9

A new Permian bactritoid cephalopod, Aktastioceras nishikawai n. sp., was discovered from the Uyamano Formation of the Taishaku Limestone Group at Miharanoro, Hiroshima Prefecture (Figure 1). The Uyamano Formation represents the Lower Permian portion of the Central Facies, which was defined by Hase et al. (1974) in a large reef complex deposited during the period of Early Carboniferous to Late Permian age. Lithofacies of the formation mainly consist of limestone, including the reef core facies with minor amounts of a limestone conglomerate. The specimens of Aktastioceras occur in light-gray massive limestone of the lowest Uyamano Formation, belonging to the Pseudoschwagerina Zone (Akagi, 1958), which indicates Asselian age. This is the first record of a Permian bactritoid from Japan.

Two species of solitary rugose corals occur in Late Ordovician strata of the St. Lawrence Lowland. Grewingkia canadensis (Billings, 1862) appears in the upper part of the Nicolet River Formation (upper St. Hilaire Member) and is far more common in the overlying Pontgravé River Formation. A single specimen of Streptelasma divaricans (Nicholson, 1875) is known from the Pontgravé River. Their presence confirms that this area is situated within the Richmond Province and that the upper Nicolet River, as well as the Pontgravé River, is Richmondian in age. Solitary Rugosa were introduced to this biogeographic province during an early Richmondian transgression, marked in the upper Nicolet River Formation by a coarser clastic interval. That event permits correlation between the St. Lawrence Lowland in the eastern part of the Richmond Province and the North American type Upper Ordovician (Cincinnatian Series) of the Cincinnati Arch region in the western part of the province.

A comparative morphologic, paleoecologic, and biostratinomic analysis of solitary corals indicates that normal, low-energy conditions were interrupted occasionally by high-energy events (probably storms) during deposition of the upper Nicolet River and Pontgravé River Formations. Water depth increased northwestward in the St. Lawrence Lowland area. Deposition of these siliciclastic prodelta to delta front sediments was generally continuous and the sedimentation rate was usually high because of rapid basin subsidence and comparatively close proximity to the Taconic Mountains. In the western part of the Richmond Province, farther from the source area, carbonate as well as clastic sediments accumulated, periods of nondeposition were more frequent, and the sedimentation rate was relatively low. Corals disappeared from the St. Lawrence Lowland area during the Richmondian, when delta top facies of the Bécancour River Formation succeeded the Pontgravé River Formation due to a glacio-eustatic regression and progradation of the Queenston Delta.

Detailed morphological study of well-preserved specimens of Bukryaster hayi (Bukry) Prins and Sissingh by means of light and scanning electron microscopes reveals that the arms of the star-shaped nannofossil are pierced by pronounced perforations, reminiscent of those of the Tertiary genus Pemma Klumpp. Those and other features differentiate the taxon from Rucinolithus hayii Stover (1966) and help delimit the stratigraphic range of this important Campanian nannofossil.

The decapods Linuparus grimmeri Stenzel, Protocallianassa mortoni (Pilsbry) and Necrocarcinus (Cenomanocarcinus) vanstraeleni (Stenzel)? are described from the middle Turonian Semilla Sandstone Member, Mancos Shale, of north-central New Mexico. The main specimen of P. mortoni is unusually complete, consisting of a complete left first cheliped, parts of other pereiopods, and most of the abdomen. Both L. grimmeri and P. mortoni are reported for the first time from the southern Western Interior. The stratigraphic range of L. grimmeri is extended upward from the upper Cenomanian, and the range of P. mortoni downward from the Campanian.

Cheilocerataceae are unique among Pennsylvanian and Permian ammonoids in having maintained the primitive sutural condition in which the ventral lobe remained entire or, in rare cases, incipiently bifid. The mature ventral lobe of all contemporary ammonoids is either prominently bifid or weakly trifid. Identity of these younger cheilocerataceans is confirmed by an additional distinctive feature, the phyletic migration of the siphuncle from a ventral position to lie close to the dorsum within the dorsal septal flexure.

Transformation of the ancestors, the Mississippian cheiloceratacean family Prionoceratidae, to produce the root-stock of post-Mississippian Cheilocerataceae was by progenesis (paedomorphosis and neoteny). This involved linear size reduction by a factor of ten, and retention to maturity of the rounded (formerly juvenile) character of the lateral lobe.

Two families are represented in the Pennsylvanian, both probably derived from a common prionoceratid ancestor. The monotypic Maximitidae (Atokan-Missourian) are distinguished by ontogenetic migration of the siphuncle from a central to ventral-marginal position, with concurrent development of incipient bifurcation of the ventral lobe in some forms. The more diverse and longer ranging Pseudohaloritidae are represented in the Pennsylvanian (Missourian and younger) by Neoaganides, an unornamented form with simple sutures that persisted to the extinction of the superfamily in the highest Permian Changhsingian Stage. During the Permian, the Pseudohaloritidae underwent explosive diversification, displayed especially by the Wordian endemics of South China. This involved bizarre combinations of shell features that are duplicated by some Mesozoic ammonoids but are rare or unique for the Paleozoic. Included are coarse ribs and nodes, and mature modifications comprising divergent coiling, one or two subterminal constrictions, and one or two pairs of spectacular lappets. In addition both the lobes and saddles may be irregularly but extremely denticulate to give “ceratitic” and “ammonitic” sutures, and the siphuncle is generally close to the dorsum. No fully plausible explanation has yet been provided for these late evolutionary developments.

All previously described taxa in the Maximitidae and Pseudohaloritidae are reviewed. New taxa include a species of Maximites that is dimorphic, three new forms of Neoaganides from the Permian of Texas and Iran, plus the first representatives of Pseudohalorites and Shouchangoceras from North America. A new genus (Sosioceras) is established for Brancoceras pygmaeum Gemmellaro. It differs from Neoaganides in having a doubly constricted aperture at maturity and well developed runzelschicht. This monotypic genus is dimorphic also, and strong dimorphism may be characteristic of Permian Pseudohaloritidae.

Sutures provide the basis for subdivision of the Pseudohaloritidae into subfamilies. The Shouchangoceratinae are “goniatitic,” the Pseudohaloritinae are “ceratitic,” and the Lanceoloboceratinae are “ammonitic.” The inadequately known Yinoceratinae, referred previously to the Thalassoceratidae, are shown to be closely related to their geographic and stratigraphic associates, the Lanceoloboceratinae. It is doubtful whether separation of the two subfamilies can be maintained. Although features such as sculpture and degree of development of serration of the suture are highly variable at the species level, gross changes in these features and in the form of the mature aperture are nonetheless the best taxobases for genera and species since the number of lobes remained constant at eight.

We used 57 morphometric characters to discriminate 17 extant and fossil Cupuladria species and analyzed their phylogenetic relationships in relation to extant Discoporella species. Data were gathered from 496 extant and fossil Cupuladria specimens ranging in age from early Miocene to Recent and distributed from the Caribbean to tropical eastern Pacific. A first series of discriminant analyses distinguished three morphological groups: Cupuladria with vicarious avicularia, Cupuladria without vicarious avicularia, and Discoporella. Further discriminant analyses identified 17 species of Cupuladria. Cladistic analyses of these three groups yielded four equally parsimonious trees. All of the consensus trees exhibited the same topology, dividing the 25 tropical American cupuladriids into four distinct monophyletic clades, including Discoporella, and are consistent with previous molecular phylogenies except that there are no molecular data for the CV2 clade. Diversification of species was higher in the CV1 and CV2 clades than CNV clade, and involved mostly Caribbean species. Cupuladria with vicarious clade 1 (CV1) includes: C. monotrema, C. pacificiensis, C. exfragminis, C. cheethami, C. biporosa, and four new species: C. pervagata, C. floridensis, C. colonensis and C. dominicana. Cupuladria with vicarious clade 2 (CV2) includes: C. multesima, C. incognita, and three new species C. collyrida, C. veracruxiensis and C. planissima. Cupuladria clade without vicarious (CNV) includes: C. surinamensis, C. panamensis, and one new species C. gigas. The stratigraphic occurrence of species is consistent with cladogram topology within clades. However hypothesized cladistic relations among clades are the reverse of their stratigraphic occurrence with younger clade CNV appearing as the hypothetical ancestor of the two older clades CV1 and CV2. More extensive collections of early to middle Miocene specimens of Cupuladria and Discoporella will be required to resolve this apparent paradox.

The Mississippian rugose corals from Alabama housed in several museums in that state are revised on the basis of current knowledge of this subclass. Fifteen species belonging to 10 genera have been identified; three species are new, including Zaphrentites lacefieldi, Palastraea cullmanense, and Siphonophyllia alabamaense. Four coral assemblages characterize four stratigraphic subdivisions of the Mississippian in Alabama: Osagean, Meramecian, lower Chesterian, and upper Chesterian. Corals are abundant in some units but diversity is quite low in all assemblages. The level of endemism is very high, except for the lower Chesterian assemblage, which contains some western Paleotethyan forms. Two possible coral evolutionary lineages have been identified.

The thorax of Hypodicranotus has ten segments and a spine on the eighth. The ages of Erratencrinurus s.l. spicatus and Erratencrinurus (Erratencrinurus?) vigilans in the Lake St. John district do not confirm their temporal roles leading to subgenera of Erratencrinurus, as has been recently suggested. Phylogenetic analyses of large data sets of species previously referred to Encrinuroides and Physemataspis yield a minimal length cladogram containing 18 species. Encrinuroides is restricted to four species, two of which have biogeographic affinities with Iapetus. These results lead to three clades, named the Walencrinuroides n. gen. clade, Frencrinuroides n. gen. clade, and finally the Physemataspis clade, with an enlarged concept of the genus with the erection of Physemataspis (Prophysemataspis) n. subgen. These last three clades are restricted to North America and Scotland, with alternating predominance of one region. Walencrinuroides s.l. gelaisi n. gen. n. sp. is described. New morphological data on Erratencrinurus s.l. spicatus confirm its close relationship with the clades discussed above. Data are insufficient for phylogenetic analysis of selected cheirurine species here surveyed. Eye position, glabellar segmentation, and pygidial shape differentiate the genera Ceraurus and Gabriceraurus; emended diagnoses of these genera are presented. Ceraurus globulobatus and C. matranseris are distinct, but morphologically close to one another. The status of Gabriceraurus dentatus can be stabilized on its extant types.

The shoo fly Complex of Late Devonian and older Paleozoic age is a regionally extensive rock assemblage in the northern Sierra Nevada of northern California. It consists chiefly of a coherent unit of phyllite, quartzose sandstone, and chert, and a melange unit (Hannah and Moores, 1986). Several limestone lenses in the Taylorsville area comprise the Montgomery Limestone (Diller, 1892, 1908; McMath, 1958; Figure 1). The Montgomery was long considered to be Silurian, largely on the basis of corals, brachiopods, and cephalopods (Diller, 1892, 1908; McMath, 1958; Berry and Boucot, 1970; Merriam, 1972). However, recent analyses of the biota indicate an Ashgill (middle Maysvillian–Gamachian) age (Boucot and Potter, 1977; Harris, personal commun. cited in Hannah and Moores, 1986, p. 790; Potter et al., 1990b; present study).