An exceptionally well-preserved specimen of Leptochiton sp. attached to a brachiopod valve is described from the early Eocene beds of the La Meseta Formation, Seymour Island. It records the first fossil Polyplacophora from Antarctica. The small specimen has eight imbricating valves, rounded lateral margins, ribs of fine granules, and growth marks in all valves. It strongly resembles extant Antarctic and South American species of Leptochiton Gray. The record of articulate valves in fossil Polyplacophora is rare and requires exceptional preservational conditions. Leptochiton sp. is associated with well preserved bryozoans, brachiopods, asterozoan echinoids, and serpulids, among other organisms that inhabited hard substrates in normal marine conditions, and probably lived attached to the side walls of an incised valley eroded in Cretaceous sediments. The well-preserved fossils were probably removed from their attachment site during storm events and, after a short transportation, rapidly buried within the early Eocene valley-fill deposits. The fossil-bearing beds are included in the Telm 2 or Acantilados Allomember of the La Meseta Formation.

The lower strata of the Umachiri Formation from the Altiplano of southeast Peru have yielded a brachiopod-dominated assemblage, containing representatives of the brachiopod superfamilies Polytoechioidea, Orthoidea, and Porambonitoidea, as well as subsidiary trilobite and echinoderm remains. Two new polytoechioid genera and species, Enriquetoechia umachiriensis new genus new species and Altiplanotoechia hodgini n. gen. n. sp. Colmenar in Colmenar and Hodgin, 2020, and one new species, Pomatotrema laubacheri n. sp., are described. The presence of Pomatotrema in the Peruvian Altiplano represents the occurrence at highest paleolatitude of this genus, normally restricted to low-latitude successions from Laurentia and South China. Other polytoechioids belonging to Tritoechia (Tritoechia) and Tritoechia (Parvitritoechia) also occur. Identified species of orthoids from the genera Paralenorthis, Mollesella, and Panderina? occur in the Peruvian Cordillera Oriental and in the Argentinian Famatina Range. The only porambonitoid represented is closely related to Rugostrophia latireticulata Neuman, 1976 from New World Island, interpreted as peri-Laurentian. These brachiopod occurrences indicate a strong biogeographic affinity of the Peruvian Altiplano with the Famatina and western Puna regions, suggesting that the brachiopod faunas of the Peruvian Altiplano, Famatina, and western Puna belonged to a well-differentiated biogeographical subprovince during the Early–Middle Ordovician on the margin of southwestern Gondwana. Links with peri-Laurentian and other low-latitude terranes could be explained by island hopping and/or continuous island arcs, which might facilitate brachiopod larvae dispersal from the Peruvian Altiplano to those terranes across the Iapetus Ocean. Brachiopods from the lower part of the Umachiri Formation indicate a Floian–?Dapingian age, becoming the oldest Ordovician fossils of the Peruvian Altiplano.

UUID: http://zoobank.org/9670a000-260d-4d75-9261-110854c7afb8

Givetian species of Chinese brachiopods previously assigned to the genus Spinatrypa or Spinatrypina reveal an internal structure characteristic of other species referred to the Eifelian genus Kerpina and the cosmopolitan Frasnian genus lowatrypa. Serial sections clarify the nature of the Middle Devonian Chinese species, which are described here as a new genus, Invertina (type species, Atrypa aspera var. sinensis Kayser, 1883). The internal structure of the Late Devonian type species of Iowatrypa, Atrypa owenensis Webster, 1921, is illustrated for the first time for comparison. These three genera, as well as three other genera, are referred to a new Devonian (Emsian-Frasnian) subfamily, the Invertininae, allocated to the family Atrypidae.

Trilobites of this suborder from Europe and North America have not been studied in detail, in contrast to the attention given to relationships within the orders Agnostida and Ptychopariina. The basis of the Corynexochina is the type species of Corynexochus from the middle Cambrian of Sweden. The type material redescribed here is only the cranidium, and is inadequate for diagnosis of the genus. A species attributed to this genus occurring in the Cambrian of southern France is represented by entire dorsal exoskeletons and is urgently in need of redescription. Similar material is recorded in northern Spain. Both complete exoskeletons and growth stages of Corynexochina have been described from Cambrian strata in Russia, Australia, Morocco and China, showing the wide geographical range and varied morphology of the Suborder. The type species of two genera from boulders of middle Cambrian age found in Quebec, Canada, are redescribed from exceptionally well preserved, though small, specimens. They appear to represent a distinct group related to some of the Zacanthoididae. Families of Corynexochina are inadequately discriminated one from another, so that a family name can only be used with question. Until this is remedied, diagnosis of a new group is not possible.

Members of the Lyttoniidae Waagen, 1883 (Lyttonioidea Waagen, 1883, Brachiopoda) are characterized by numerous peculiarities, including their disproportionately inequivalve, rudimentary articulatory apparatus and asymmetrically developed muscle scars. The ventral valve of lyttonioids usually possesses a posterior flap and complementary septal apparatus and the dorsal valve has corresponding lobes and slits to fit around the ventral septa (Noetling, 1905; Fredericks, 1926; Wanner, 1935; Williams, 1953; Grant, 1976; Williams et al., 2000). Externally, the Lyttoniidae have been previously described as being smooth or having some growth banding, lines, or disturbances only (Cooper and Grant, 1974; Williams et al., 2000). Spines were previously reported by Sarytcheva (1964), but subsequently not confirmed by Cooper and Grant (1974, p. 387) and Williams et al. (2000). Radial ornamentation has never been reported prior to this study. In 2002, two specimens with Linoproductus-like costellae and Old-hamina-like septal apparatus were found by one of the authors (CLR) from the Middle Permian Xiala Formation at the Xinji Section in the Xainza area (89–91°E, 30–31°N) in northern Tibet (Fig. 1.1, 1.2) during 1:250,000 mapping. We consider that the present specimens represent another distinct phylogenetic branch within the Lyttoniidae, although only two specimens were found. Further collecting is currently impossible because of the inaccessibility of the remote area in northern Tibet. In this paper we aim to propose a new subfamily of Lyttoniidae based on the specimens found from northern Tibet.

Based on multivariate morphometric analysis, Halysites catenularius is identified from the Rumba Formation (Telychian) and Jaagarahu Formation (Sheinwoodian) of Estonia; H. priscus is confirmed as a junior synonym. Halysites catenularius, H. junior, and H. senior are shown to be closely related; H. catenularius is morphologically intermediate. Cyclomorphism in H. catenularius, recorded by fluctuations of corallite tabularial area, indicates an average annual growth rate of 6.0 mm, which is typical for halysitids. Tubules in H. catenularius, generated from small intramural openings between adjacent corallites, were involved in two types of interstitial increase. The intramural openings, three types of lateral increase, temporary agglutinated patches of corallites, and axial increase documented in H. catenularius resemble features in some species of Catenipora. These similarities are consistent with the interpretation that Halysites evolved from Catenipora. Evaluation of the possibility that both genera are polyphyletic will require further detailed analysis of additional species.

Endothyroid foraminifers are common in most marine Pennsylvanian units in the Appalachian Basin. The genera Planoendothyra Reitlinger, 1959, and Endothyranella Galloway and Harlton, 1930, are the dominant taxa. Scarce Endothyra Phillips, 1846, are restricted below the Desmoinesian. The greatest change in stratigraphic distribution of taxa occurs at the Atokan-Desmoinesian boundary.

Sixteen taxa are recognized. Five new species are proposed, including Planoendothyra orbiculata, P.? associata, Endothyranella kentuckyensis, E. inflata, and E. intermissa. Most taxa are assigned previously described American species using a cf. designation. Description and thin section illustration provide a basis for nomenclatural acceptance of these taxa.

Platymerella from the lower Red Mountain Formation in Georgia and Tennessee, the Bowling Green Dolomite of west-central Illinois, and the Elwood Dolomite of northeastern Illinois represents a paleosubtropical, cool-water occurrence of virgianid brachiopods in Laurentia during the early Silurian (middle–late Rhuddanian). These occurrences were located in the southern Appalachian foreland basin and the distal end of the Sebree Trough, likely subjected to frequent cool-water current and upwelling from Gondwana. Compared with broadly coeval species of Virgiana from lower paleotropical to equatorial latitudes, Platymerella has significantly smaller, dorsoventrally flattened shells, with subequal ventral and dorsal umbones and beaks that extend only slightly above the hinge line. Relative to its shell size, however, Platymerella has more prominent thickening of the shell wall, median septum, spondylium, and hinge plates than Virgiana, resembling more closely the extravagant shell thickening of Tcherskidium and Proconchidium from the Late Ordovician (late Katian) equatorial regions. The thickening of hinge plates resulted in the formation of a pseudocruralium, which separates Platymerella from Virgiana. In latest Ordovician–earliest Silurian virgianids, there was a general morphological gradient toward a smaller shell, reduction in the ventral-valve convexity, and reduction in the size and height of the ventral umbo from paleoequatorial to southern subtropical regions, with Platymerella representing the most southerly forms.

Several specimens of biogenic structures somewhat resembling plug-shaped ichnofossils have been collected in two muddy deposits, Sicilian (Early Pleistocene) in age (Bossio et al., 1987), outcropping near Lecce, southern Apulia, Italy. One sequence is exposed in an unused quarry located at the eastern side of the Cutrofiano–Supersano road, 31 km post; the other one is in an active quarry, southwest of Lecce, near the village of San Pietro in Lama (Figure 1). The diagnostic features of the traces differ from those of the five ichnogenera recognized by Pemberton et al. (1988) for plug-shaped ichnofossils. The minor ichnogenera related to plug-shaped trace fossils, as indicated by those authors, are also different from the present structure. A new ichnogenus is proposed to cover this form.

In 1892 the Swedish paleontologist Johan Christian Moberg described and illustrated what he interpreted as a fossil insect (Hemiptera) from beds of early Ordovician age in the southernmost limestone quarry at Killeröd, Smedstorp Parish in Skåne [Scania], southern Sweden. In a later paper in the same year (Moberg, 1892b), he also made a further passing reference to the presence of the same fossil when describing the accompanying graptolite fauna from Killeröd. One of his main reasons for recording this find was his conclusion (Moberg, 1892a, p. 122) that “it is evidently of great interest with full certainty to be able to prove the presence of airbreathing (terrestrial) animals as far back in time as that during which the oldest strata of the lower Silurian [i.e., Ordovician] were formed” [translation from Swedish].

The calcareous heteractinid sponge Wewokella solida Girty, 1911, is reported from Colorado for the first time. Triactine-based skeletons are well preserved and dermal and gastral layers are composed of smaller spicules than those in the main wall of the many specimens. A fragment of an unnamed demosponge, possibly related to Heliospongia Girty, 1908, and fragments of root tufts occur with Wewokella in the Middle Pennsylvanian Minturn Formation near McCoy, in Eagle County, Colorado.

Morphometric analysis demonstrates that Strepsidura ficus (Gabb) of Harris (1895), from the lower middle Eocene Reklaw and Queen City Formations of Texas, is specifically distinct from Whitneya ficus Gabb (1864) of the Californian Eocene. Accordingly, the new name Strepsidura harrisi is proposed for the Texas species. Strepsidura s.s. is represented in North America by S. ficus (Gabb), S. harrisi n. sp., and an unnamed species closely related to S. harrisi in the upper Paleocene Sequin Formation of Texas. Strepsidura s.s. apparently originated in the Old World Tethyan Realm during the Paleocene and subsequently spread to North America.

In the 1950s, Carlos Rusconi reported the biostratigraphically important Furongian trilobites Elvinia Walcott and Irvingella Ulrich and Resser from an exotic limestone block (La Cruz Olistolith) of the San Isidro area, Precordillera of Mendoza, western Argentina. Although several local species were erected by Rusconi at that time, most of them were later listed as junior synonyms of E. roemeri (Shumard) or I. major Ulrich and Resser, and this was followed in subsequent studies. A systematic revision of all the available specimens of Elvinia and Irvingella from the Rusconi collection at the Museo de Ciencias Naturales y Antropológicas J.C. Moyano (Mendoza) is provided herein. The occurrence of E. roemeri is supported by the present study, while the associated Irvingella species include I. jorusconii Rusconi, I. platycephala Rusconi, and Irvingella sp. The latter represent “advanced” forms in terms of morphological development in the Irvingella lineage, and these, together with E. roemeri, are typical of the uppermost part of the Elvinia Zone (uppermost Steptoean). Irvingella jorusconii, I. platycephala, and Irvingella sp. appear to be endemic to the Argentinian Precordillera, but are related to species from central Texas and northwest Canada.

The homalonotid trilobite Burmeisteria Salter, 1865 is revised from material from the Lower Devonian of central western Argentina (the Talacasto Formation in the Precordillera Basin). In contrast to other closely related Devonian marine basins from South America (mainly Bolivia, Brazil and Uruguay), the only species recognized in Argentina include Burmeisteria herschelii (Murchison, 1839) and B. notica (Clarke, 1913). New observations on the structure of the carapace indicate that structures sometimes interpreted as granules with taxonomic meaning are, in fact, taphonomic characters that represent the fillings of pore canals exposed by decortication. The antero-ventral process of the rostral plate may be a locking device during enrollment, which allowed long-term defensive behavior with a minimum of muscular energy. Burmeisteria is an upper Silurian to Middle Devonian endemic representative of southwestern Gondwanan (Malvinokaffric) basins. In the Argentine Precordillera Basin, this genus is virtually restricted to a sandy, Pragian, stratigraphic interval capped by a marker bed first reported by Keidel in 1921.

Several specimens of the gigantic new species, Wewokella costata, have been recovered from the Upper Missisippian Hartselle Sandstone of Marshall County, east of Huntsville, in northeastern Alabama. The large sponges have flutted columnar growths and basic skeletons of triactines that are grossly encrusted or overgrown by calcium carbonate to produce massive fused skeletons. These are the oldest and largest specimens of Wewokella yet certainly identified. Wewokella costata has a skeleton with reduced numbers of triactines, but with extensive calcareous cement. The species could be in the lineage leading to the Inozoida Rigby and Senowbari-Daryan, 1996, which have spicule-free skeletons of sphaeroidal aragonite.

The genus Abertella Durham, 1953 initially was described to include one of several problematic species of Miocene sand dollars originally placed in Scutella Lamarck, 1816. Durham (1953) named Scutella aberti Conrad, 1842 as the type of Abertella, and later (1955) tried to resolve issues concerning familial relationships of North American scutellines by placing the genus in a monogeneric family, the Abertellidae. Durham (1953, p. 351) separated Abertella from other members in his assemblage of taxa related to Scutella because the former has: 1) an immediately submarginal periproct between the second pair of post-basicoronal plates; 2) moderately closed petaloids about three-quarters the length of the corresponding aboral ambulacrum (although he states this ratio as being two-thirds in the description itself); 3) widely disjunct oral interambulacra; 4) ambulacral basicoronals that are larger than interambulacral basicoronals (misstated, and corrected to say just the reverse in Durham [1955]); and 5) a well-developed notch in the posterior margin of the test. Abertella aberti (Conrad, 1842) is known from the coastal Miocene of the eastern United States, notably Maryland, North Carolina, and Florida (Durham, 1953; Cooke, 1959; McKinney, 1985).

A small faunule of silicified hexactinellid sponges and root tufts has been recovered from the upper Guadalupian Reef Trail Member of the Bell Canyon Formation, from the Patterson Hills, in the southwestern part of the Guadalupe Mountains National Park in western Texas. Some demosponges from the type section of the Reef Trail Member, near the mouth of McKittrick Canyon on the front of the Guadalupe Mountains in the park, have also been documented. Included in the faunule from the Patterson Hills localities are the new amphidiscosid hexactinellid pelicasponge Trailospongia reischi n. gen. and sp., the questionable pelicaspongiid Hexirregularia nana n. gen. and sp., and the dictyospongiid hexactinellids Microstaura doliolum Finks, 1960, and Microstaurella minima n. gen. and sp., and Microstaurella parva n. gen. and sp. They are associated with specimens of the lyssacinosid brachiosponges Toomeyospongiella gigantia Rigby and Bell, 2005, Toomeyospongia modica n. sp., and Toomeyospongia minuta n. gen. and sp., and fragments of three different types of root tufts, termed Tufts 1, 3, and 4. Two specimens of the new cylindrical demosponge Mckittrickella pratti n. gen. and sp. are associated with Tuft 2 in the collection from the type section of the Reef Trail Member, and a third specimen was collected from the member in the Patterson Hills. These sponges from Localities 1-7 are the youngest Permian sponges known from the region, and possibly from North America.

Argenthina emilyae is a new genus and species of extinct muricid gastropods from the early Middle Miocene of southern Argentina. Most of its shell features are consistent with those of the Acanthina-clade of Thais-like ocenebrines, including a broad, rounded body whorl, a large aperture lacking ornamentation, and a short, open siphonal canal, although other characters are consistent with the Ocinebrina-like ocenebrines, such as the differentiation of axials into varices and intervaricals and complex spiral sculpture. This combination of traits is unique in the Ocenebrinae. It is not yet clear whether this new taxon represents an episode of morphological experimentation by a stem group of Thais-like ocenebrines resulting in convergence on the Ocinebrina-like shell form or an evolutionarily intermediate step between Thais-like and Ocinebrina-like ocenebrines. Intermediates are expected from previously published phylogenetic hypotheses for the Ocenebrinae that suggest Ocinebrina-like ocenebrines have evolved multiple times from Thais-like ocenebrines. Until now, however, such intermediates have not been reported from the fossil record.

Rousseauspira teicherti, a new genus and species of an unusual, untwisted, horn-shaped gastropod operculum from shallow-subtidal limestones of the Upper Ordovician of Alaska and the Middle Ordovician of California, is described and compared to two other Ordovician opercula, Ceratopea Ulrich, 1911, and Teiichispira Yochelson and Jones, 1968. The shell to which the operculum belonged is not yet known.

A partial cranium and axial skeleton of an individual Symbos cavifrons were excavated in 1983 from the Mesa Verde Loess on Grass Mesa, Montezuma County, Colorado. Parts of at least 24 bones were recovered, including the first complete set of cervical vertebrae known for Symbos cavifrons. This individual, radiocarbon dated at 15,970 ± 155 yr B.P. (SI-6137), contributes to the definition of the southwestern edge of the range of the species and provides new information about the nature of the vertebral column. Pathologic constriction of the transverse canals is evident in the third and seventh cervical vertebrae. The pattern of bone distribution suggests that carnivores consumed part of this animal. The radiocarbon date also establishes the last major episode of loess deposition in the Four Corners region of the southwestern United States.