Tropidoleptus is a brachiopod genus with a very peculiar morphology that existed throughout the Devonian as a cosmopolitan taxon. Although there have been reports of the presence of this genus in the Paraná Basin since the nineteenth century, its actual occurrence has been the subject of much debate. The objective of this paper was to clarify this situation. For this purpose, dozens of specimens from Monjolo dos Padres and Juscimeira outcrops (São Domingos Formation, possibly Givetian) in the Brazilian state of Mato Grosso were analyzed. The samples studied here exhibit the typical characteristics of Tropidoleptus, confirming that this genus also occurred in the Paraná Basin. It is possible that Tropidoleptus entered the Paraná Basin during the Eifelian/Givetian from the Amazonas and/or Parnaíba basins (Brazil), during a period of warm-water transgression. When Tropidoleptus is found in situ, it can serve as an indicator of a shallower water environment (shoreface to shallower portions of transitional offshore). In the Paraná Basin, its presence can indicate rocks no older than the Eifelian–Givetian transition.

The siphonophrentidae is a family of Devonian rugose corals that are known mostly from eastern North America, a part of the Eastern Americas biogeographical Realm (EAR) during the Devonian. Breviphrentis Stumm, 1949, has been considered a siphonophrentid by most previous authors and, in a recent monograph (Oliver, 1993), I described three EAR species as Breviphrentis and referred others to the genus.

Trilobites from the upper Guzhangian of the southern Argentine Precordillera, preliminarily described by Carlos Rusconi in the 1950s, are revised herein. The specimens studied were collected from an allochthonous limestone block of La Cruz Olistoliths at 200 m northwest of Estancia San Isidro locality (San Isidro area, Mendoza). Taxa comprise Kormagnostus seclusus (Walcott, 1884), Cedaria prolifica Walcott, 1924, C. puelchana Rusconi, 1954, Tricrepicephalus texanus (Shumard, 1861), Meteoraspis metra (Walcott, 1890), Coosia conicephala (Rusconi, 1954) new combination, Coosella texana? Resser, 1942, Nasocephalus cf. N. nasutus Wilson, 1954, and Olenoides proa (Rusconi, 1954) new combination. The North American genera Meteoraspis Resser, 1935 and Nasocephalus Wilson, 1954 are reported confidently from South America for the first time. This assemblage is representative of the Cedaria prolifica Zone, which correlates with the lower Crepicephalus Zone of the traditional North American genus-based zonation. Most of the genera and species identified were previously described exclusively from Canada, the United States, and northwestern Mexico, a fact that provides new support to an allochthonous Laurentian origin of the Argentine Precordillera.

The Mississippian was a time of widespread diversification of pelmatozoan echinoderms in the United States. The crinoids and blastoids were diverse and abundant in a variety of geologic settings. Most of the Osagean occurrences of blastoids are associated with platform carbonates such as the Burlington Limestone. These blastoids lived in association with a crinoid community dominated by camerate crinoids. Blastoids also lived in coeval Osagean deltaic environments such as the Borden Delta but were less diverse and abundant.

Among Permian smaller foraminifers, the genus Dagmarita is one of the most studied due to its worldwide distribution. The detailed study of the Zal (NW Iran) and Abadeh (Central Iran) stratigraphic sections led to redescription of the genus Dagmarita and its taxonomic composition. In Dagmarita, a peculiar generic morphological character, represented by a secondary valvular projection, has been detected for the first time among globivalvulinid foraminifers. The phylogeny of Dagmarita, and in particular its ancestor Sengoerina, is discussed and the new species, D. ghorbanii n. sp. and D. zalensis n. sp., are introduced. Analogies and differences among all the species belonging to Dagmarita are highlighted and morphological features of the new taxa are shown in 3D reconstructions, useful for understanding differently oriented sections of the specimens in thin section.

UUID: http://zoobank.org/3d8eb14c-7757-4cbd-877c-4bacd2d156da

Bryozoans are abundant and diverse in the upper part of the Chainman Shale (Mississippian; Osagean, Meramecian-Chesterian) and in the upper Chesterian part of the overlying Ely Limestone (Mississippian-Pennsylvanian) in the Confusion Range of western Utah. The bryozoan assemblage includes 15 genera and 18 species; 12 species are new and 6 are in open nomenclature. The new species are the trepostomes Callocladia jensensis, Stenopora confusionensis, Stenoporella mineriensis, Tabulipora atacta, T. ricta, T. sarcinula, T. stragula, the cryptostomes Ascopora macellata, Rhabdomeson artum, Streblotrypa angulatum, Strebloplax pertusa, and the cystoporate Cystodictya astrepta. Species in open nomenclature are the trepostome Anisotrypa sp., the cryptostomes Saffordotaxis sp., Archimedes sp., Fenestella sp., Penniretepora sp. A, and Polypora sp. Callocladia and Strebloplax are known only from Chesterian strata in North America; Strebloplax is known only from the conterminous United States. The stratigraphic range of Stenoporella, also known only from the United States, is extended into rocks of supposed Pennsylvanian age. Stenoporella mineriensis, the only species in this bryozoan assemblage known to occur outside Utah, is also found in the Ely Limestone (Pennsylvanian) of Nevada.

Tabulipora is the dominant genus in the Chesterian rocks of this region; T. sarcinula and T. ricta are the most abundant taxa. The shallowing of the marine environment and the establishment of carbonate deposition during late Chainman time permitted widespread development and dispersal of the bryozoan faunas in western Utah.

Webster (1991) is to be congratulated for clarifying the validity of the various contributions made to the literature of fossil echinoderms by V. J. Gupta. However, in correcting the paleogeographic database, an error has crept in which itself needs amending.

Two life positions of fossil naticid opercula are recognized in Pliocene deposits of Hokkaido, northern Japan. In one position, the operculum seals the aperture. In the other position, the operculum is pressed against the shell base adjacent to the aperture. The death position of the head-foot mass can be reconstructed from the two opercular positions, which coincide, respectively, to naticids that died with the head-foot mass retracted into the shell, and those that died with it entirely extended from the shell.

The apparatus of Vogelgnathus simplicatus (Rhodes, Austin, and Druce, 1969) is reconstructed from discrete elements from a sample of limited diversity from the Limerick Province (Ireland). The apparatus is typical of the order Ozarkodinida and the P1 element was previously placed within Gnathodus. Here we assign it to Vogelgnathus by applying a multielemental concept rather than using P1 element morphology. The holotype and paratypes are re-illustrated and the species distribution revised based on published data. Vogelgnathus simplicatus ranges from the late Tournaisian to the early Viséan (Mississippian, Carboniferous), with common occurrences relating to the growth of Waulsortian bank complexes in a high-stand sea-level along the southern and western margins of the Laurussian landmass (Belgium, the British Isles, the Republic of Ireland, and USA). Vogelgnathus simplicatus appears to represent the rootstock from which deep-water and shallow-water Viséan species of Vogelgnathus evolved in the Mississippian.

An assemblage of 34 chiton valves collected from rocks of the “Imperial” Formation sensu lato at Super Creek near Palm Springs, California, is described here. The sedimentary rocks exposed at Super Creek were deposited in the proto-Gulf of California during the Late Miocene. This chiton assemblage represents the first reported Miocene chitons from western North America. The chiton valves are classified as Callistochiton cf. C. elenensis, Chaetopleura cf. C. lanuginosa mixta, Calloplax roederi n. sp., Chiton solaris n. sp., Callistoplacidae sp. indet., and Chaetopleuridae sp. indet. Thick valves dominate the assemblage. The chiton fossils reflect the overall faunal pattern from the “Imperial” Formation s.l. of a strong similarity to taxa in the modern Gulf of California, with a Caribbean component as well. This assemblage fills a gap in the chiton fossil record and preserves details of the adaptive radiation of the Polyplacophora that occurred at the time in concert with the onset of an upwelling regime.

UUID: http://zoobank.org/9947bfc9-84a3-4358-bac7-e660b936b067

Rousseau h. flower (1913-1988) collected and published widely in paleontology during a career that spanned more than 50 years. Although Rousseau did significant paleontological work while employed elsewhere, the major part of his career was spent at the New Mexico Bureau of Mines and Mineral Resources (NMBM&MR), a career that included a decade of work after his formal retirement (Wolberg, 1988). During his life, Rousseau built a very large fossil collection based upon his own field work., materials other scientists referred to him for study, material sent to him by serious amateurs, and collections Rousseau borrowed from other institutions and was unable to return before his death. The NMBM&MR is attempting to find and return all borrowed material. Similarly, we intend to transfer much described fossil material to major repositories with appropriate facilities for their maintenance in order to make the fossils available to as many interested students as possible. The guidelines for the transfer of this material were set by Rousseau before his death.

A diverse Permian crinoid fauna is reported from the Taiyuan Formation, Dajian Member (Asselian) at Anyang, northeastern Henan Province of the North China Craton. The specimens are well preserved, including articulated crowns and cups. The fauna contains representatives of each of the major Paleozoic crinoid clades: Cladida (including the Flexibilia), Disparida, and Camerata. Identified genera suggest a greater affinity with North American faunas than with Tethyan faunas. Four new species, Neoprotencrinus anyangensis, Ulocrinus qiaoi, Artichthyocrinus limani, and Synbathocrinus chenae, are proposed herein.

UUID: http://zoobank.org/D08DDDCD-485C-45CC-A014-C1CB58C26588

Early Devonian (Pragian-Emsian) rocks in the Xainza region of central Xizang (Tibet) yield a shallow-marine, carbonate-platform fauna of corals, brachiopods, dacryoconarids, nautiloids and conodonts, among which Tibetatrypa n. gen. is locally a prominent constituent. The fauna broadly resembles that of western Europe, the Altai-Sayan region, the Urals and western Qinlin province of China, but differs from the South China faunas. Tibetatrypa, related to the Silurian genus Nalivkinia, is the youngest and largest member of the subfamily Clintonellinae, and is the first Devonian brachiopod described from Tibet.

Ichthyerpeton bradleyae (Huxley in Wright and Huxley, 1866) is one of the seven tetrapods originally described by Huxley from the Jarrow Assemblage (Pennsylvanian, Langsettian Regional Substage equated with the Bashkirian International Stage) in south-eastern Ireland. The holotype, one of only two specimens considered to represent the taxon, consists of the postcranial skeleton, which has been highly compressed and has undergone extensive replacement of bone by carbonaceous material. The holotype is studied using microcomputed tomography, which reveals that the vertebral column has at least 25 diplospondylous vertebrae with cylindrical centra. Neural arches and a haemal arch are described for the first time. Neural arches in the caudal region are paired and neural spines only contact one another dorsally. The hemal arch is fused and wraps around the ventral margin of the centrum. A stout femur and tibia are described. The morphology of the femur is unique for early tetrapods, with fibular and tibial condyles of similar length and lacking an adductor crest. The morphology of the femur, and its length relative to the tibia, suggests that the holotype of I. bradleyae preserves an immature individual. The tibia is a flat bone characteristic of stem tetrapods. Phalanges from the right and left pes are present. Because the phalanges are disarticulated, a phalangeal count cannot be determined. Despite the new anatomical information, the systematic position of I. bradleyae is still difficult to establish; however, it does not belong within the colosteids, temnospondyls, or embolomeres, to which it has previously been assigned.

An enigmatic microproblematicum, Tuxekanella Riding and Soja (1993), has been identified in the shallow water carbonate succession of the Late Silurian Skala formation (Podolia, Ukraine). the newly found specimens suggest most probably the algal nature of this enigmatic microfossil. Tuxekanella is known only from two extremely distant regions at the moment: the Alexander terrane in Alaska and Podolia. the possibility of their paleobiogeographical link is discussed in the context of paleotectonic models, assuming the peri-Gondwanan origin of the Alexander Terrane.

The geologic record of the shallow-marine gastropod genus Pseudoperissolax Clark, 1918 is documented in detail for the first time in a region of the northeast Pacific extending from southwestern Washington to northern Baja California, Mexico. This genus, which has been erroneously equated with the nomen dubium Perrisolax Gabb, 1861, comprises a very small group of species whose supra-generic ranking has been inconsistent. Pseudoperissolax is placed here in family Muricidae Rafinesque, 1815 and subfamily Muricinae Rafinesque, 1815 based on the presence of varices, a club-shaped last whorl with noded carinae, and a long siphonal canal. The genus is represented in the northeast Pacific by the late Paleocene Pseudoperissolax tricarnatus (Weaver, 1905) and the late Paleocene to late Eocene Pseudoperissolax blakei (Conrad, 1855).

Pseudoperissolax was a warm-water gastropod that most likely originated during the Late Cretaceous (Maastrichtian) in Madagascar and also questionably spread during this time to southern New Zealand. Its certain geologic range is early Paleocene to earliest Oligocene, with occurrences in western Kamchatka, southern Japan, southwestern Washington, southwestern Oregon, southern California, northern Baja California, Mexico, southern Alabama, and Nuevo León, northeastern Mexico. Whether Pseudoperissolax migrated into the northeast Pacific from Kamchatka or from Alabama and Mexico cannot be determined with certainty. The decline and eventual extinction of the genus coincided with the global-cooling event at the end of the Eocene.