Scorpionid Resting Trace from The Lower Permian of Southern New Mexico,USA

We describe an arthropod body impression associated with arthropod trackways of the ichnogenus Stiaria from the Lower Permian (upper Wolfcampian) Robledo Mountains Formation (Hueco Group) in the Prehistoric Trackways National Monument of southern New Mexico. The probable producer of these traces was a scorpion, and we name the likely scorpionid resting trace Alacranichnus braddyi, new ichnogenus and ichnospecies. There are no prior reports of scorpionid body impressions from terrestrial settings in the fossil record.     

Trace fossils of the arthropod Camptophyllia from the Westphalian (Carboniferous) rocks of Lancashire, UK and their palaeoenvironmental context

Two arthropod trace fossils are described and analysed from the Carboniferous Lower Westphalian (C. communis and basal A. modiolaris chronozones) coal-bearing strata of Lancashire. The biserial trackway Diplichnites triassicus consists of five overlapping en echelon sets of 7–9 tracks preserved as epichnia and hypichnia in lacustrine siltstones. The trackway suggests subaqueous in-phase walking by a multi-segmented producer with a body length of 35–40 mm, width 17–22 mm, and 7–9 appendages. Curved, clustered, or laterally repeated, hypichnial lobes with transverse striations on the base of ripple cross-laminated sandstone are identified as Rusophycus versans. This trace fossil is interpreted as shallow resting or furrowing burrows of a homopodous arthropod, 30–60 mm long, 15–30 mm wide, and probably the same kind of arthropod as produced D. triassicus.A review of contemporary arthropod body fossils from Lagerstätten in Lancashire favours the onisciform, or Arthropleura like arthropod Camptophyllia as a potential producer of both of these trace fossils in a lacustrine palaeoenvironment.This study integrates the analysis of sediments, trace fossils and body fossils for reconstructing the arthropod biota and ecology in Westphalian lacustrine and crevasse splay fluvial palaeoenvironments.     

Insights on the Behavior of Late Paleozoic Aquatic Crustaceans (Pygocephalomorpha?): Compound Trace Fossils from Western Argentina

We describe intergradations between the arthropod repichnial trace fossils Diplichnites gouldi (Gevers et al., 1971), Dendroidichnites Demathieu et al., 1992, and Monomorphichnus Crimes, 1970 with two distinct cubichnial traces, Gluckstadtella cooperi Savage, 1971 and Huilmuichnus santracruzensis new ichnogenus and ichnospecies. These compound ichnofossils are part of high ichnodiversity arthropod-dominated trace fossil associations from the Late Carboniferous Agua Escondida Formation of the San Rafael Basin (Argentina). The complex ichnotaxonomy of Diplichnites and the ichnospecies D. gouldi are discussed and some possible working solutions are proposed. The most likely producer of the compound trace fossils are the Pygocephalomorpha, a group of Late Paleozoic crustaceans that are recorded in nearby basins from Uruguay and Brazil. The compound trace fossils are used to infer a number of complex behaviors of pygocephalomorphs in a subaqueous setting, including caridoid (tail flip) or more primitive escape reactions, landing followed by resting and transient resting during normal walking. In addition, different gaits can be inferred from well-preserved D. gouldi, which can be correlated with contrasting trackway morphology.     

Vallodiscus gen. nov., a new fossil resting spore morpho-genus related to the marine diatom genus Chaetoceros (Bacillariophyceae)

A new fossil marine diatom resting spore morphogenus, Vallodiscus Suto gen. nov., is described using samples from Deep Sea Drilling Project Site 338 in the Norwegian Sea, Sites 436 and 438 in the north‐west Pacific Ocean and the onland Newport Beach Section, California. Vallodiscus is characterized by a single ring of veins along the epivalve margin and a hypovalve covered with circular depressions of several sizes with gentle elevation. The morpho‐genus bears three new species and one new combination: Vallodiscus simplexus Suto sp. nov., Vallodiscus complexus Suto sp. nov., Vallodiscus lanceolatus Suto sp. nov. and Vallodiscus chinchae (Mereschkowsky) Suto comb. nov.     

Small shelly fossils and trace fossils near the Precambrian-Cambrian boundary in the Yukon Territory, Canada

In the past an ‘explosion’ in diversity and abundance of small shelly fossils and of trace fossils has served to mark the base of the Cambrian. However, no evidence has been presented to prove that the ‘explosions’ of the two groups were synchronous. We describe small shelly fossils and trace fossils from the same phosphatic limestone beds that indicate that the two events were separate in time. The small shelly fossils are Anabarites trisulcatus, Hyolithellus cf. H. isiticus, Microcornus? sp., Protohertzina anabarica, P. unguliformis, P. sp. A, Pseudorthotheca sp. A, Rushtonia? sp. A, four types of tuberculate plates and one type of reticulate plate. These fossils represent a restricted, ‘pre-explosion’ fauna and are assigned to the Anabarites-Circotheca-Protohertzina Assemblage Zone, an uppermost Precambrian zone in the Meishucun Stage, Yunnan Province, China. A point at the top of this zone has received strong international endorsement for future designation as the base of the Cambrian. Associated with the small shelly fossils are the trace fossils Cruziana sp. A, Cruziana? sp. B, Rusophycus sp. A, Palaeophycus rubdark and arthropod scratch marks. If found in isolation, this trace fossil assemblage would be considered as post-Precambrian because it includes large, highly organized arthropod traces that are traditionally accepted as occurring above the trace fossil ‘explosion’. We therefore conclude that the trace fossil ‘explosion’ predates the small shelly fossil ‘explosion’. If the proposed location of the base of the Cambrian in Yunnan is accepted, the small shelly fossil ‘explosion’ concept and its relationship to the boundary would not be greatly modified. The trace fossil ‘explosion’, however, would no longer indicate the base of the Cambrian and the ranges of some trace fossils would be extended into the Precambrian.     

Spinicaudatans and ostracods (Crustacea) from the Montceau Lagerstätte (Late Carboniferous, France): morphology and palaeoenvironmental significance

Spinicaudatans and ostracods form two components of the diverse arthropod fauna from the Montceau Lagerstätte (Stephanian, France). Spinicaudatans are represented by Montcestheria orri gen. and sp. nov. and Euestheria feysi sp. nov., and ostracods by a single species, Carbonita sp. aff. salteriana (Jones, 1862). Allied forms such as Montcestheria sp. aff. orri, Montcestheria sp. and Euestheria cebennensis (Grand'Eury, 1890), all from coeval localities in France, are also described. Montcestheria gen. nov. has carapace features, external (possibly sexual) dimorphism, preserved soft parts (e.g. appendages, gut) and resting eggs similar to those of Recent spinicaudatans, suggesting comparable lifestyles, reproductive strategies and feeding modes. Detailed anatomical comparisons are made with Cyzicus tetracerus from Recent ephemeral freshwater ponds. The ostracods belong to the Superfamily Carbonitoidea, which is a recurrent component of Carboniferous non‐marine biotas. Spinicaudatan‐rich assemblages typically occur in several Westphalian–Stephanian Lagerstätten (including Montceau) and localities from Europe and North America, where freshwater conditions prevailed, indicating that the group had already colonized continental waters by the Late Carboniferous. Similarities with the fauna from Recent temporary freshwater ponds (e.g. low diversity/high density spinicaudatan‐ostracod populations, synchronous spinicaudatan populations developing from resting eggs, high diversity/low density insects, amphibians) suggest the presence of temporary or ephemeral aquatic environments at Montceau as part of a complex limnic ecosystem. Flooding may have been the main driving force by which faunal and floral elements drifted away from their respective biotopes into the depositional areas, thus explaining the co‐occurrence of terrestrial (e.g. myriapods, scorpions, plants), amphibian and aquatic (e.g. conchostracans and syncarids from temporary and permanent settings, respectively) elements in fossil assemblages.     

Ichnologic Note A New Ichnospecies of Cardioichnus from the Cretaceous (Albian) of New Mexico

A new ichnospecies of Cardioichnus, Cardioichnus biloba isp. nov., is described and documented from shallow marine strata of Cretaceous (Late Albian) age in southern New Mexico, USA. It is a heart-shaped resting trace which, unlike all other ichnospecies of Cardioichnus, is epichnial and increases in width to a bilobate trace, often with a raised anterior terminus. Only the posterior end of this trace is associated with Bichordites burrows, and the anterior end is bilobate and undisturbed. This represents a resting position which differs from other known species of this cubichnium, which are hypichnial and subquadrate in symmetry. The tracemaker is a spatangoid echinoid, most likely Heteraster d'Orbigny, 1853.     

Saccoglossus testa from the Mazon Creek fauna (Pennsylvanian of Illinois) and the evolution of acorn worms (Enteropneusta: Hemichordata)

The limited fossil record of enteropneust hemichordates (acorn worms) and the few external features that distinguish the four families have provided a challenge to our understanding of the evolution of the group and their various feeding adaptations. The middle Pennsylvanian Saccoglossus testa sp. nov. from the Mazon Creek, Westfalian D Carbonate Formation, Francis Creek Shale of northern Illinois provides evidence for the exploitation of surface sediments. Saccoglossus testa has a long proboscis characteristic of the extant genus Saccoglossus, a specialist in surface deposit feeding. The collar is as long as it is wide. The anterior trunk lacks a distinctively wide branchial region. These three features distinguish it from its sympatric enteropneust species Mazoglossus ramsdelli Bardack that has a proboscis characteristic of an infaunal deposit feeder. It is the seventh known species of fossil enteropneust, including a resting trace of a Lower Triassic fossil that has collar lips that characterize the extant deep‐sea family Torquaratoridae, and which represents a second parallel evolution of surface deposit feeding. An analysis of the seven fossils shows that the earliest Enteropneusta had a relatively simple harrimaniid‐like body plan, and that the spengelid, the torquaratorid and lastly the most complex ptychoderid body plan appeared in that chronological order.     

Tursia—A New Ichnogenus from Pleistocene Shallow Water Settings in Southern Italy

Abstract

Tursia flabelliformisigen. et isp. nov. is described from the lower Pleistocene Argille Subappennine Formation near Tursi, southern Italy. The trace fossil occurs in protected sandy shoreface sediments and is associated with abundantBichordites. Tursia is a vertical fan-shaped spreite structure that is interpreted as the feeding trace of a deep infaunal deposit-feeding organism, either bivalve or “worm.”     

Review of the stratigraphic distribution of Permian grylloblattida (Insecta), with descriptions of New Taxa

New taxa of grylloblattid insects (Grylloblattida) are described: Tshekardomina mongolica, sp. nov. (Tshekardominidae) from Bor-Tologoi locality (Severodvinian Stage of Mongolia), Permoshurabia mesenensis, gen. et sp. nov. (Geinitziidae) from Soyana fossil site (Kazanian Stage of Arkhangelsk oblast), Khosaridelia vyatica, sp. nov. (Permotermopsidae) from Karaungir II locality (Vyatkian Stage of Kazakhstan), Euremisca kazanica, sp. nov. (Euremiscidae) from Soyana fossil site (Kazanian Stage of Arkhangelsk oblast), Megakhosarina vyaznikensis, sp. nov. (Megakhosaridae) from Balymotikha locality (Vyatkian Stage of Vladimir oblast), and Parascalicia prokopensis, gen. et sp. nov. (Skaliciidae) from Prokop’evsk fossil site (Kazanian Stage of Kemerovo oblast). The genera Lodevopterum Béthoux, Nel, Lapeyrie et Gand, 2005 (Lodève fossil site, France), Elmopterum Béthoux et Beckemeyer, 2007, and Sigmophlebia Béthoux et Beckemeyer, 2007 (Elmo and Midco fossil sites, United States) are transferred from Grylloblattida incertae sedis to families Euremiscidae, Aliculidae, and Tshekardominidae, respectively. The stratigraphic distribution of Permian grylloblattid families is reviewed.     

A large arthropod from the Lower Old Red Sandstone (Early Devonian) of Tredomen Quarry,south Wales

Abstract: A large arthropod from the Lower Old Red Sandstone of Tredomen Quarry, near Brecon, Powys, southeast Wales is described as Bennettarthra annwnensis gen. et sp. nov. The animal is incomplete, preserved to a length of 30 cm, and displays a trunk of at least ten, non‐diplopodous segments. The trunk may be delineated into two distinct tagmata: the anterior three somites (as preserved in the fossil) appearing ornamented and apparently bearing robust, ornamented, segmented walking legs; the posterior somites appearing relatively smooth, of which at least the anterior five somites bear simple, sclerotized rudimentary appendages. Unfortunately, diagnostic features such as detailed appendage arrangement for the anterior tagma and the head and tail region are largely missing, frustrating detailed classification. However, the delineation of the non‐diplopodous trunk into two tagmata, each displaying apparently distinct appendage morphology, together with the large size of the fossil, is a feature hitherto unknown in any arthropods from terrestrial/freshwater fossil assemblages of this age. In terms of taxonomic placement, based on the currently limited morphological evidence, a malacostracan or hexapodan affinity for Bennettarthra appears most likely. The animal is preserved in laminated sandstone with plant debris, osteostracan fish and abundant thin irregularly shaped carbonaceous sheets. The sandstone was deposited from a river flood that buried and preserved articulated fish and Bennettarthra. These animals were probably buried alive and suffocated in sediment. Trace fossils including Diplichnites trackways and Beaconites burrows occur in close stratigraphic proximity to the flood deposit, and it is possible that this arthropod was the maker of one or both of these traces.     

A new coral‐associated decapod assemblage from the Upper Miocene (Messinian) Upper Coralline Limestone of Malta (Central Mediterranean)

Abstract: A rich coral‐associated decapod assemblage is recorded from the ‘Depiru Beds’ of the upper part of the Upper Coralline Limestone (Messinian, Upper Miocene), from the island of Malta. Nineteen species within 17 genera have been discovered, where 14 genera are new for Malta. Four new species are described, namely Micippa annamariae sp. nov., Pilumnus scaber sp. nov., Panopeus muelleri sp. nov. and Herbstia melitense sp. nov. Herbstia melitense sp. nov. constitutes the first record of the genus from the fossil record in the Mediterranean region. This discovery more than doubles the number of known fossil decapod species from Malta. The fossil bivalve Jouannetia (J.) semicaudata Des Moulins, 1830 and the extant decapod Maja goltziana D’Oliveira, 1888, are also recorded for the first time from Malta. Other Neogene coral‐associated decapod assemblages are investigated and correlated with the new assemblage from Malta. The migration of taxa between the Mediterranean region and the Paratethys, particularly during the Lower Badenian (Langhian), is evidenced by the strong affinity of the Maltese decapod assemblage with that of the Middle Miocene Badenian assemblages from Hungary, Poland and Ukraine. Upper Miocene, Messinian assemblages from Spain, Algeria and Morocco are also similar to that from Malta.     

New trace fossil evidence for eurypterid swimming behaviour

We describe a recently discovered trace fossil from a eurypterid Konservat‐Lagerstätte in the upper Silurian Tonoloway Formation of Pennsylvania, and formally describe contemporaneous traces from the Williamsville Formation Lagerstätte of Ontario. The traces from both localities are assigned here to Arcuites bertiensis igen. et isp. nov. Based on comparisons with previously described eurypterid trackways, neoichnological experiments, and the co‐occurrence with eurypterid remains, Arcuites is interpreted as having been made by the swimming leg (sixth prosomal appendage) of swimming juvenile to adult eurypteroid eurypterids, and represents the first unambiguous trace fossil evidence for eurypterid swimming behaviour. The morphology of Arcuites indicates that eurypteroid eurypterids swam using drag‐based rowing, whereby the animal propelled itself forward by moving its oar blade‐like swimming paddles in an in‐phase backstroke. Arcuites morphology also indicates that the eurypteroid swimming appendage had a greater degree of movement than was previously suggested, and a revised rowing model is proposed. Differences in the abundance of A. bertiensis in the Tonoloway and Williamsville formations suggest a bathymetric control on eurypterid swimming behaviour and trace production. The association of Arcuites with eurypterid body fossils in both units indicates that these Lagerstätten were autochthonous assemblages and provides additional evidence for eurypterid inhabitation of shallow subtidal marine environments in the late Silurian.     

Ichnology of deep‐sea fan overbank deposits of the Ganei slates (Eocene,Switzerland)— a classical flysch trace fossil locality studied first by Oswald Heer

Ganei (Switzerland) is a classical locality for trace fossils. At this site, Heer (1877) described a large number of trace fossils, several of which were new taxa. The trace fossils occur in thin‐bedded turbidites in which the basal divisions of the Bouma sequence are typically absent; the turbidites are assigned to the Ganei Slates and are Eocene in age. They are interpreted to have been deposited in an overbank environment within an upper to middle fan area distal to a channel. Two trace‐fossil associations occur: the first (I) is characterized by bulldozing organisms producing biodeformational structures, Scolica, and Nereites irregularis; the second (II) association shows a distinct tiering pattern with near‐surface graphoglyptids and a mixed layer with simple tubes such as cf. Palaeophycus and Planolites, plus patterned tubes such as Nereites cirrinalis, and Chondrites. Deeper turbidite layers were colonized by Chondrites and Gyro‐phyllites. All trace fossils show a normal size spectrum compared to previously studied trace‐fossil associations, so the degree of oxygenation probably did not influence the composition of either trace‐fossil association. Seafloor sediment was probably soft and did not affect the trace‐fossil associations. Sedimentation rate and event frequency did not change and are estimated to have been in a range of 5–10 cm/1000 years and 2–5 events per 1000 years, respectively. The composition of trace‐fossil associations I and II is therefore interpreted to have been controlled by the benthic food content being higher for trace‐fossil association I than for II.     

INDIAN OCEAN NANNOPLANKTON. II. HOLOCOCCOLITHOPHORIDS (CALYPTROSPHAERACEAE,PRYMNESIOPHYCEAE) WITH A REVIEW OF EXTANT GENERA1

Holococcolithophorids, pyrmnesiophytes having only one type of calcareous element in their coccoliths, are delicate and not commonly recorded in recent and fossil marine floras. There are few records of these organisms from the Indian Ocean and 26 species from there are included in this report. Although the group, generally assigned to a single family, the Calyptrosphaeraceae, may contain species that are part of the life history of heterococcolith-bearing cells in other stages, so little is known of this aspect of their biology that one must continue, at the present time, to treat them as independent taxonomic entities. A key is provided for the known holococcolithophorid genera. A new genus, Gliscolithus, and three new species, Gliscolithus amitakarenae, Calyptrosphaera heimdalae, and Helladosphaera pienaarii are described. The following new combinations are proposed: Calyptrolithina fragaria (Kamptner) comb. nov., Calyptrolithina gaarderae (Borsetti et Cati) comb. nov., Calyptrolithina isselii (Borsetti et Cati) comb. nov., Calyptrolithina lafourcadii (Lecal) comb. nov., Calyptrolithina magnaghii (Borsetti et Cati) comb. nov., Calyptrolithina multipora (Gaarder) comb. nov., Calyptrolithina porritectum (Heimdal) comb. nov., Calyptrolithina wettsteinii (Kamptner) comb. nov., Calyptrolithophora catillifera (Kamptner) comb. nov., Calyptrolithophora galea (Lecal-Schlauder) comb. nov., Dactylethra pirus (Kamptner) comb. nov., Helladosphaera arethusae (Kamptner) comb. nov., Helladosphaera gracilis (Kamptner) comb. nov., Homozygosphaera strigilis (Gaarder) comb. nov. and Syracolithus schilleri (Kamptner) comb. nov. The new combination in the genus Dactylethra Gartner for the first time brings an extant species into this genus that formerly contained only fossil species. It is pointed out that the enlarged zygoliths in stomatal areas of Corisphaera and the helladoliths in stomatal regions of Helladosphaera have intergrading types and are not distinctive enough characteristics to separate these genera.     

A New Endosymbiont in Late Ordovician Tabulate Corals from Anticosti Island,Eastern Canada

Cylindrical tubes of the trace fossil Chaetosalpinx occur within the skeletal walls of Late Ordovician sarcinulid tabulate corals preserved on Anticosti Island. A large host-specific embedment structure, Chaetosalpinx rex isp. nov., is described from the reefal sarcinulid genus Columnopora that occurs in (Rawtheyan, Ashgill) coral-stromatoporoid patch reefs of the upper Vauréal Formation (Mill Bay Member). While locally abundant in Columnopora, this newly described embedment structure is absent in other frame-builders in the reefs.     

The Complex Fungal Microboring Trace Saccomorpha stereodiktyon isp. nov. Reveals Growth Strategy of its Maker

A complex microboring trace of fungal affinity is described in shells as a new ichnotaxon Saccomorpha stereodiktyon isp. nov. and compared with the earlier established ichnotaxon Saccomorpha terminalis Radtke, 1991. The new trace is characterized by a three-dimensional network of tunnels composed of a bifurcate horizontal (parallel to substrate surface) network with an upright (perpendicular to surface) system of tunnels and by the formation of cylindrical to multilobate terminal sporangial swellings. The new trace shares with Saccomorpha terminalis Radtke, 1991 the terminal position of sporangial swellings but differs from this ichnotaxon by its complexity in spatial arrangement, segmented construction, and ramification of tunnels. The horizontal parts of the network in the new taxon adhere to the substrate surface and regularly produce thinner tunnels that explore the interior of the substrate, allowing the producer to participate in digestion of organic lamellae incorporated in the shell. Microborings similar to the new trace fossil have been observed in modern bivalve shells of the Atlantic Ocean, North Sea, Adriatic Sea and Red Sea at depths ranging from the intertidal down to 1,550 m. The fossil record of the trace reaches back to the Jurassic and the type material stems from a Lower Oligocene oyster shell. The study shows that complex microboring traces reflect both behaviour and developmental strategy of their makers.     

First decapod crustaceans in a Late Devonian continental ecosystem

The origin and early diversification of decapod crustaceans and their expansion from marine to continental environments are key events in arthropod evolution. Rare fossil decapods are known from the Palaeozoic, and the earliest eumalacostracans with undoubted decapod affinities are the Late Devonian Palaeopalaemon and Aciculopoda, found in offshore marine deposits. Here, we describe a new species of the shrimp Tealliocaris found in floodplain and temporary pond deposits from the Famennian (Late Devonian) of Belgium, together with a rare Palaeozoic assemblage of other crustaceans (conchostracans, notostracans and anostracans) and chelicerates (eurypterids). Tealliocaris walloniensis sp. nov. documents the earliest occurrence of continental decapod crustaceans and indicates that decapods have been part of continental ecosystems at least since the Late Devonian.