A first report of Sphenothallus Hall, 1847 in the Cambrian of Variscan Europe

Ten specimens of two phosphatic fossils have been recently discovered in lower and middle portions of Middle Cambrian Jince Formation in the Czech Republic. They are attributed to the genus Sphenothallus Hall, 1847 and described as two separate species; comparatively small conchs are described as S. kozaki sp. nov., the much larger specimens characterized by its smooth and partly flexible organo-phosphatic walls of shell are determined as ?S. kordulei sp. nov. Sphenothallus is known to range from Cambrian to Permian and accommodates numerous species. However, its Cambrian distribution is considerably restricted. Generally rare specimens have been described from Lower to Middle Cambrian of Laurentia and from the Lower Cambrian of Gondwana and peri-Gondwana. The new record of Sphenothallus from the Jince Biota represents a notable extension of their geographic range.     

Occurrence ofByronia Matthew andSphenothallus Hall in the Lower Cambrian of China

Rare phosphatic tubular fossils from the Lower-Middle Cambrian Kaili Formation of Guizhou Province, southern China were originally identified as non-calcified algae or ‘worms’ (ScoleciellusLiu). Re-examination of these fossils indicates that specimens identified as non-calcified algae areSphenothallus taijiangensis n. sp., while specimens identified asScoleciellus belong toByronia natus (Liu).Sphenothallus taijiangensis andByronia natus from Lower Cambrian strata in the Kaili Formation are the oldest known representatives of their genera. In addition,B. natus (Liu) is the only known species ofByronia with the exception ofB. annulata Matthew (Middle Cambrian, British Columbia). CambrovitusMao et al., a tubular fossil from Middle Cambrian strata in the Kaili Formation, originally was classified as a hyolithid. However, the discovery of a nearly complete specimen possessing an apical attachment disk shows thatCambrovitus, likeByronia andSphenothallus, probably was a thecate cnidarian polyp.     

Sphenothallus »Vermes« in the Early Devonian Hunsrück Slate,West Germany

Five specimens ofSphenothallus have been observed in Early Devonian slates from West Germany which have been studied bv radiographs. This genus has been assumed by several authors to be a “worm tube” or that it may belong to the Conulata. Some individuals show soft parts extending from the aperture. All preserve a bilaterally symmetrical tentacular apparatus.Sphenothallus could be related to the Annelida, but cannot be placed in that phylum since no evidence of segmentation is preserved. In specimens from other localities,Sphenothallus has been observed to have a chitinophosphatic tube, unlike the calcareous tube of living tube-dwelling annelids. What can be observed of the apertural soft parts indicates a mode of life similar to that of members of the modern-day annelid order Sabellida.     

New Alicornops (Rhinocerotidae) remains from Lower and Middle Siwaliks,Pakistan

Unpublished rhinocerotid remains from the Lower and Middle Siwaliks of Pakistan are described in this paper and recognized as two species of Alicornops. Alicornops complanatum (Heissig) is identified in the Dhok Pathan Formation of the Middle Siwaliks and Alicornops laogouense Deng in the Kamlial Formation of the Lower Siwaliks. The Dhok Pathan Formation levels with A. complanatum are roughly correlated with the late Miocene-Pliocene European mammal zones MN10-15. In turn, levels with A. laogouense of the Kamlial Formation would correlate with the middle–late Aragonian (middle Miocene) European MN5. The recognition of the Chinese species A. laogouense in the Potwar Plateau represents the first discovery of this taxon in Pakistan and increases the geographical and stratigraphic distributions of this species, and adds to the rhinocerotid association from the Siwaliks. In turn, the presence of A. complanatum in the Siwaliks of Potwar Plateau also enlarges its geographic distribution in Pakistan, as it was previously known from the Bugti Hills of Balouchistan. The absence of Alicornops from the Siwaliks in the Chinji and Nagri formations (between late MN5 and MN9 zones) might be due to an inadequate fossil record, as other rhinocerotid species are known from Kamlial to Dhok Pathan formations. However, the two recorded species of Alicornops could also reveal two independent migration waves as supported by the appearance of other taxa in different formations. A summary of fossil Cenozoic rhinocerotids from different areas of Pakistan is also presented.     

The origin of tetraradial symmetry in cnidarians

Serially arranged sets of eight septa‐like structures occur in the basal part of phosphatic tubes of Sphenothallus from the early Ordovician (early Floian) Fenxiang Formation in Hubei Province of China. They are similar in shape, location and number, to cusps in chitinous tubes of extant coronate scyphozoan polyps, which supports the widely accepted cnidarian affinity of this problematic fossil. However, unlike the recent Medusozoa, the tubes of Sphenothallus are flattened at later stages of development, showing biradial symmetry. Moreover, the septa (cusps) in Sphenothallus are obliquely arranged, which introduces a bilateral component to the tube symmetry. This makes Sphenothallus similar to the Early Cambrian Paiutitubulites, having similar septa but with even more apparent bilateral disposition. Biradial symmetry also characterizes the Early Cambrian tubular fossil Hexaconularia, showing a similarity to the conulariids. However, instead of being strictly tetraradial like conulariids, Hexaconularia shows hexaradial symmetry superimposed on the biradial one. A conulariid with a smooth test showing signs of the ‘origami’ plicated closure of the aperture found in the Fenxiang Formation supports the idea that tetraradial symmetry of conulariids resulted from geometrical constrains connected with this kind of closure. Its minute basal attachment surface makes it likely that the holdfasts characterizing Sphenothallus and advanced conulariids are secondary features. This concurs with the lack of any such holdfast in the earliest Cambrian Torellella, as well as in the possibly related Olivooides and Quadrapyrgites. Bilaterally arranged internal structures in polyps representing probably the oldest medusozoans support the suggestions based on developmental evidence that the ancestor of cnidarians also was a bilaterally symmetrical animal. This is one more example of fossil data that strictly fit the molecular phylogenetic evidence but not necessarily morphology‐based zoological interpretations.     

Lapworthellids and other skeletonised microfossils from the Cambrian Stage 3 of the northern Montagne Noire,southern France

The Montagne Noire (southern France) possesses one of the most complete Cambrian successions in the western peri-Gondwana margin and might provide a good stratigraphic reference for both regional charts and international correlations. However, to date, the lower Cambrian succession of the northern Montagne Noire has been supposed to be devoid of biostratigraphically significant fossils. The complex tectonostratigraphic framework of the area (a range divided into Axial Zone, northern and southern Montagne Noire) exacerbated problems related to regional correlations and palaeogeographic reconstructions. As a result, the chronostratigraphic context of the lower Cambrian of northern Montagne Noire is still uncertain and stratigraphic reports have broadly relied on putative lithostratigraphic correlations with the southern Montagne Noire. The purpose of this study is to characterise, for the first time, the fossil record of carbonate beds and lenses of the northern Montagne Noire occurring at the top of the siliciclastic-dominated Marcory Formation, in order to provide regional bio- and chronostratigraphic constraints on lower Cambrian strata. Moreover, this study is aimed at improving international chronostratigraphic correlation. Carbonate beds and lenses cropping out along the Orque Cliff, in the Mélagues thrust slice, were investigated. They yielded a faunal assemblage constituted of molluscs (Igorella cf. ungulata and Igorella moncereti n. sp.), hyoliths (Conotheca brevica), chancelloriids (Archiasterella cf. pentactina and Allonnia sp.) and tommotiids (Lapworthella rete). L. rete is recorded in upper Meishucunian (Cambrian Stage 3) strata of the Yangtze Platform (South China) where it is used as index fossil of the Cambrian Stage 3 Sinosachites flabelliformis–Tannuolina zhangwentangi Assemblage Zone. Therefore, the presence of this tommotiid provides evidence that the studied carbonate beds and lenses are Cambrian Age 3 (Atdabanian according to the Siberian chart). The upper part of the Marcory Formation in the Mélagues slice, dated as Cambrian Stage 3, might represent a lateral equivalent of the mixed (carbonate-siliciclastic) Pardailhan Formation defined in the southern Montagne Noire.     

Discussion of the Early Devonian rhynchonellid brachiopod genus Borealirhynchia Su, 1976

The Early Devonian brachiopod genus Borealirhynchia was established by Su, 1976. Phylum Brachiopoda (Cambrian to Devonian). In: Paleontological Atlas of North China, Inner Mongolia Volume 1. Geological Publishing House Beijing, pp. 155-227 (in Chinese). It has not been previously described in detail, nor have transverse serial sections of the internal features of Borealirhynchia delerensis, the type species, been published. In this paper Borealirhynchia, along with a few species previously assigned to it, is analysed and discussed. Detailed transverse serial sections of the internal features of B.? lata Su, 1976, are provided, based on well-preserved specimens collected from the Lower Devonian strata of Dong Ujimqin Qi, northeastern Inner Mongolia. Borealirhynchia? gigantea Su, 1976 and Latonotoechia multicosta Su, 1976 are considered to be synonyms of B.? lata Su with the same external and internal characters present in all three species. Some Lower Devonian strata, in which Borealirhynchia was found and reported, from Dong Ujimqin Qi, northeastern Inner Mongolia, are fully described.     

Palaeobiogeographical provenance, taphonomy, and mode of life of Aturia cubaensis (Cephalopoda, Nautiloidea) from Cainozoic deposits of Chile

The presence of Aturia cubaensis (Lea) is reported from several Cainozoic localities along the central and southern Chilean coast. The shells are very well preserved and the ultrastructure of the shell, especially of the siphuncular tube, of A. cubaensis is described and the function of the siphuncular tube discussed. A. cubaensis shows an interesting distributional pattern in Chile, becoming more frequent towards higher latitudes. It occurs in the Navidad, Ranquil, and Lacui formations of central and southern Chile and the Cameronian Stage of Tierra del Fuego, spanning a time of Eocene-Oligocene to latest Miocene, possibly even earliest Pliocene. Tierra del Fuego is the southernmost record of this species. The preservation of Aturia in all these localities is exceptionally good, no incrustation and microboring is observed in the shells. Post-mortem shell breakage is present, but usually the phramocone is not destroyed. These records contradict either the subtropical to tropical nature of the genus Aturia or existing climatic reconstructions for the southeastern Pacific during the middle to late Cainozoic. A number of southern South American names for nautiloids are synonymized with A. cubaensis: Nautilus maldonadi Philippi, Nautilus caroliameghinoi Ihering, Aturia (Sphenaturia) brueggeni Ihering, Aturia (Sphenaturia) felschi Ihering. Nautilus araucanus Philippi and Nautilus magellanicus Philippi are nomina nuda but presumably also synonyms of A. cubaensis.     

A revision of chamaeleonids from the Lower Miocene of the Czech Republic with description of a new species of Chamaeleo (Squamata, Chamaeleonidae)

A revision of Chamaeleo caroliquarti Moody and Ro?ek is presented. The comparisons of the holotypic left dentary with those of specimens subsequently assigned to C. caroliquarti and of the Recent species of Chamaeleo, Furcifer and Calumma is carried out. It is shown that the type dentaries of C. caroliquarti include two different morphotypes with the absence of unique features. Within the Recent chameleons, the exact determination of the individual species merely on the basis of the dentaries is impossible. The holotypic dentary of C. caroliquarti is basically identical with that of C. calyptratus. However, the same morphology of the dentary as present in C. caroliquarti is also present in other species of different genera such as Calumma globifer and Furcifer pardalis. The paratypic dentaries of C. caroliquarti have a different morphology to the holotype and are indistinguishable from that in the Recent C. chamaeleon. On the other hand, a new species of the genus Chamaeleo, C. andrusovi, is described on the basis of isolated cranial elements, which possess clear autapomorphic features. This material comes from the Lower Miocene (Ottnangian) zone MN 4 in the Dolnice locality of the Czech Republic, and it differs from Recent and fossil chameleons in the following combination of characters: (1) its typically developed strongly pustular ornamentation and its distribution on the external surfaces of the skull roofing bones; (2) the frontoparietal suture is digitiform with a well-developed, anteriorly directed mesial spine, and (3) the parietal bone narrows posteriorly at its midlength, it is not bowed dorsally and it does not contribute posteriorly to a dorsal sagittal crest. This new material expands our knowledge of the cranial anatomy of Lower Miocene chameleons.     

First report of Gogia (Eocrinoidea, Echinodermata) from the Early-Middle Cambrian of Sonora (Mexico), with biostratigraphical and palaeoecological comments

The blastozoan echinoderm genus Gogia is reported for the first time in the Early and the Middle Cambrian of Mexico. Reports in different members of the section of San José de Gracia (Sonora State, northwestern Mexico) extend the palaeogeographical range of the genus to the South Laurentia, and the stratigraphic range of Gogia granulosa to the whole first half of middle Middle Cambrian. Isolated plates occur in rocks deposited in detrital inner platform and complete specimens, in carbonate outer platform, confirming their ability to live in diverse environments. Their presence in these different environments through the Early-Middle Cambrian on Laurentia agrees with the onshore-offshore expansion of echinoderms during Cambrian.     

Discovery of the Jehol Biota from the Celaomiao region and discussion of the Lower Cretaceous of the Bayingebi Basin,northwestern China

Some typical components of the Jehol Biota, including conchostracans Eosestheria sp., the mayfly Ephemeropsis trisetalis Eichwald, 1864, the aquatic beetle Coptoclava longipoda Ping, 1928, and a fragmentary dragonfly, are reported for the first time from the Bayingebi Formation in the Celaomiao region, western Inner Mongolia, China. This discovery indicates that the middle Upper Member of Bayingebi Formation can be correlated with the upper Yixian and the lower Jiufotang formations in western Liaoning Province. Combining it with the radio-isotopic dating result, we further believed that the Upper Member of Bayingebi Formation could be roughly correlated with the Yixian, Jiufotang, and Shahai formations, and the overlying Suhongtu Formation with the Fuxin Formation in western Liaoning Province.In the major Bayingebi Basin, palaeontological and radio-isotopic dating evidence shows that the Bayingebi Formation has a long depositional history of over 30 Ma: its Upper Member bearing the Jehol Biota and the early Fuxin Biota is probably coeval to the Yixian, Jiufotang and Shahai formations and has a Barremian–early Albian age; its Lower Member may be Berriasian–Hauterivian in age and could be correlated with the upper Tuchengzi, Zhangjiakou, and Dabeigou formations in northern Hebei Province. This suggests that the Bayingebi Formation should be promoted to the stratigraphic rank of group and subdivided into several secondary units (formations). Unlike the previous result, the Yingen Formation is considered across the Lower Cretaceous–Upper Cretaceous boundary and being late Albian–early Turonian in age.     

Dental microwear texture analysis of hominins recovered by the Olduvai Landscape Paleoanthropology Project, 1995-2007

Dental microwear analysis has proven to be a valuable tool for the reconstruction of aspects of diet in early hominins. That said, sample sizes for some groups are small, decreasing our confidence that results are representative of a given taxon and making it difficult to assess within-species variation. Here we present microwear texture data for several new specimens of Homo habilis and Paranthropus boisei from Olduvai Gorge, bringing sample sizes for these species in line with those published for most other early hominins. These data are added to those published to date, and microwear textures of the enlarged sample of H. habilis (n = 10) and P. boisei (n = 9) are compared with one another and with those of other early hominins. New results confirm that P. boisei does not have microwear patterns expected of a hard-object specialist. Further, the separate texture complexity analyses of early Homo species suggest that Homo erectus ate a broader range of foods, at least in terms of hardness, than did H. habilis, P. boisei, or the “gracile” australopiths studied. Finally, differences in scale of maximum complexity and perhaps textural fill volume between H. habilis and H. erectus are noted, suggesting further possible differences between these species in diet.     

Morphology of Luolishania longicruris (Lower Cambrian,Chengjiang Lagerstätte,SW China) and the phylogenetic relationships within lobopodians

New material of the lobopodian Luolishania longicruris has been recovered from the Lower Cambrian Chengjiang Lagerstätte, southwest China. The specimens throw new light on several morphological features of the species, including the paired antenniform outgrowths, eyes, head shield, setae and other cuticular projections, as well as the differentiated sclerites, appendages, claws, and lobopod interspaces. L. longicruris shows well developed tagmosis: a distinct head and a trunk divided into two sections. The new data allow a revised comparison with other lobopodians. Miraluolishania haikouensis Liu et al., 2004 is considered to be a junior synonym of L. longicruris Hou and Chen, 1989. Evidence from gut filling and specialized morphological characters indicates that L. longicruris may have had a filter feeding lifestyle. A new cladistic analysis suggests that fossil lobopodians are paraphyletic or even polyphyletic and L. longicruris may be an important representative of the stem lineage leading to arthropods.     

The identity of Tetracyclus constrictus (Bacillariophyceae) and a description of Tetracyclusbradburyii, a new miocene species

The siliceous valves from species of Tetracyclus (Bacillariophyceae) have variable but characteristic shapes. In this paper, species characterised by having valves with a central constriction are discussed. This distinctive shape occurs during only a period of its lifecycle. Tetracyclus constrictus and Tetracyclus celatom have been applied to fossil specimens occurring in deposits from the west coast of the USA and the east coast of Russia. Do these names apply to two closely related species or are they one and the same taxon? Two further species, Tetracyclus javanicus and Tetracyclus peragalli, have been involved in the identity of T. constrictus–T. celatom. T. constrictus M. Peragallo is the correct name and author for specimens of the extinct Miocene, circum-Pacific (or northern) fossil species with valves panduriform with rounded poles; T. javanicus refers to a species found living on Java only; fossil specimens usually referred to T. javanicus (Java) belong to a new taxon, Tetracyclus bradburyii (USA); T. peragalli is an extinct Miocene fossil, with a northern hemisphere distribution; small (≤10 μm) circular/elliptical fossil specimens, found alongside other specimens, are difficult (if not impossible) to determine to species level.     

Crypto-helical body plan in partially disarticulated gogiids from the Cambrian of South China

All living echinoderms have a pentaradial symmetry that is unique within the Bilateria. However, the Cambrian origin of echinoderm radial/pentaradiate symmetry is a long-standing problem. During the Cambrian (542–488 Ma), gogiids were the most common stalked echinoderm characterized by an “irregularly” plated body. Based on recently discovered material from the Balang Formation (Cambrian Series 2), eastern Guizhou, China, three unusual, partially disarticulated specimens of Guizhoueocrinus have clear evidence for a helical body plan. This helical plating is only evident in partially disarticulated specimens, thus a crypto-helical body construction is present. Crypto-helical construction in a gogiid raises the possibility of a phylogenetic connection among helicoplacoids, gogiids, and Helicocystis. The crypto-helical body construction may be an important evolutionary innovation among pre-radiate echinoderms.     

New data on crinoid assemblages from the oldest sedimentary rocks of the Polish Outer Carpathians (Jurassic-Cretaceous)

Crinoids (Crinoidea) preserved in the so-called Cieszyn Beds (Tithonian-Hauterivian; southern Poland) are relatively numerous, especially in some levels, but not highly diversified. They are absent in the Lower Cieszyn Shale (Tithonian) and the Upper Cieszyn Shale (Valanginian-Hauterivian). The Lower Cieszyn Limestone (Tithonian) yielded crinoid remains classified as Isocrinus cf. amblyscalaris (Thurmann) and Isocrinida indet. In the Upper Cieszyn Limestone (Berriasian) crinoids are much more numerous and diversified. The following taxa are recorded: Isocrinus? annulatus (Roemer), Balanocrinus subteres (Münster), B. cf. smithi Hess and Gale, and Hemicrinus sp. The presence of specimens resembling Isocrinus amblyscalaris (Thurmann) in the Tithonian strata is surprising since the last occurrence of this taxon was reported from the Kimmeridgian. The Lower Cieszyn Limestone crinoidal assemblage is dominated by isocrinids (Isocrinida). This probably reflects the much shallower sedimentary environment of these sediments compared to that of the Upper Cieszyn Limestone, where excepting isocrinids, hemicrinids (Hemicrinidae, Cyrtocrinida) typical for deep marine environments were found. It is consistent with the analytical results from the foraminiferal assemblages, among which the benthic forms known from shelfal and paralic epicontinental environments first dominated, and then were supplanted by deep-sea taxa at the turn of the Jurassic and Cretaceous.     

Microscopic evidence of serpulid affinities of the problematic fossil tube ‘Serpula’ etalensis from the Lower Jurassic of Germany

Tube structure, ultrastructure and mineralogy support serpulid affinities of the problematic worm fossil ‘Serpula’etalensis from the Lower Jurassic of Germany. The original tube mineralogy of ‘Serpula’etalensis is purely aragonitic and is preserved in Upper Pliensbachian specimens from eastern Germany. ‘Serpula’etalensis represent the earliest record of aragonitic mineralogy for serpulids. The tube is formed of irregularly oriented prismatic crystals that are 3–6 µm in length and 0.5–1.0 µm in diameter. Calcitic specimens of ‘Serpula’etalensis from Upper Sinemurian of southwestern Germany were recrystallized during the diagenesis and lack the original tube ultrastructure.     

Evolution of C isotopes in the Cambrian of China: implications for Cambrian subdivision and trilobite mass extinctions

Carbon and oxygen isotopes were studied in fossiliferous Cambrian carbonates in northwestern Hunan Province (South China) and in northern Anhui and southern Shandong provinces (North China). Two major C isotope excursions related to biological events occur in the Wangcun section (Yongshun County, northwestern Hunan), which consists of a slope carbonate sequence (510 m thick) containing abundant trilobites. The first C isotope excursion (δ¹³C value shifts from -2.3‰ to 2‰) occurs near the boundary between the Qingxudong and Aoxi formations, close to the traditional Lower-Middle Cambrian boundary. The second excursion (δ¹³C value shifts from 0‰ to 3‰) occurs in the interval between the Linguagnostus reconditus Zone and the Glyptagnostus reticulatus Zone. The base of the G. reticulatus Zone define the base of the Paibi Stage and Furongian Series. Similar C isotope excursions also occur in shallow - water carbonate sections in North China. In Jiagou section near Huainan (Anhui Province), recently considered an important interval for defining the lower-middle Cambrian boundary because of dramatic changes in the trilobite fauna (extinction of redlichiids and appearances of ptychopariids), a negative C isotope excursion (δ¹³C value shifts from +1.21‰ to -1.93‰) occurs at the top of the lower member of the Mantou Formation. In the Gushan section (Changqing County, Shandong Province), a C isotope excursion (δ¹³C value shifts from -0.04‰ to 2.23‰) occurs at the base of the Changshan Formation and is coincident with the base of the Chuangia Zone. This excursion can be correlated with the excursion in the lower part of Glyptagnostus reticulatus Zone in the Wangcun section. The above two distinct C isotope excursions, which occur both in slope carbonates in South China and in shallow - water carbonates in North China, have also been recognized in Cambrian sections on other continents, and they coincide with global mass extinctions of trilobites. The two excursions evidently reflect global changes of Cambrian sea level, and they have utility for Cambrian subdivisions and for both regional and global stratigraphic correlation. In addition, a negative carbon excursion below the base of the Ptychagnostus atavus Zone in the Wangcun section supports previous suggestions that the FAD of P. atavus can be considered as a global correlatable horizon within the middle Cambrian.     

Occurrence of the Lower Cambrian anemone-style trace fossils in the Zabuk Formation (Mardin–Derik,SE Turkey)

The Zabuk Formation of the Derik Group exposed over much of south-eastern Turkey presents a succession composed of shallow marine and fluvial siliciclastic sedimentary rocks. The Lower Cambrian assemblages containing abundant anemone-style trace fossils are known from most major palaeocontinents such as Laurentia, Baltica, and Gondwana. These have possible affinities with semi-infaunal dwelling anemones on siliciclastic mid-latitude shelves of West Gondwana in early Fortunian deposits. Among them is Bergaueria, characterized by plug-shaped burrows as exemplified by Bergaueria perata, that is, a characteristic trace fossil of the Cambrian globally.