Neoichnology Research Papers - Academia.edu (original) (raw)

To cite this article: Monaco P., Famiani F. & la iacona F. (2016)-bulldozing and resting traces of freshwater mussel Anodonta woodiana and substrate characteristics in lake-margin and river settings of Umbria, italy. Riv. It. Paleont. Strat., 122(1): 53-62. Abstract. The neoichnology of the freshwater mussel Anodonta (Sinanodonta) woodiana (lea, 1834) is examined herein in some continental environments of Umbria (central italy), such as lake-margin and river dam-margin settings. This study, based on analysis of about 200 traces, reveals that this mussel burrows employing two types of behaviours: bulldozing which produces horizontal meanders to straight bilobate traces, often filled with peloidal faecal pellets (pseudofaeces and backfill), and resting (vertical stationary into substrate) while filter feeding. A new type of very soft substrate, the 'cloudground' is proposed. it is placed at the water-sediment interface, above the soupground. after four years of observation, the cloudground was buried with shells and traces, preserving through the fossili-zation barrier about 20% of the Anodonta traces. This bivalve activity is a useful tool to recognize preservation of mud in quiet environments and parallels ichnological evidence of unknown epichnial trace fossils in the continental realm. Cloudground with resting traces must be investigated also in modern marine basin floor environments where cloud of mud dominates and considered also in geological record.

- by Paolo Monaco
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- Invertebrate Ichnology, Neoichnology

Paleo- and neoichnology of the Lepe area (Huelva, SW Spain) have been studied. In particular, the Pliocene trace fossil record at the ‘Arroyo Valleforero’ section and the burrowing activity of part of the estuarine invertebrate and vertebrate organisms observable in the Piedras Estuary (mainly at the Nueva Umbría Spit and the Piedras marshes) have been described in detail. The comparison between them allows establishing analogies and getting a better understanding about the paleontological and sedimentological evolution of this area of the southwestern Spanish Atlantic coast from the upper Neogene until today.

- by Zain Belaústegui
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- Paleoichnology, Pliocene, Bioturbation, Neoichnology

The neoichnology of the freshwater mussel Anodonta ( Sinanodonta ) woodiana (Lea, 1834) is examined herein in some continental environments of Umbria (central Italy), such as lake-margin and river dam-margin settings. This study, based on analysis of about 200 traces, reveals that this mussel burrows employing two types of behaviours: bulldozing which produces horizontal meanders to straight bilobate traces, often filled with peloidal faecal pellets (pseudofaeces and backfill), and resting (vertical stationary into substrate) while filter feeding. A new type of very soft substrate, the ‘cloudground’ is proposed. It is placed at the water-sediment interface, above the soupground. After four years of observation, the cloudground was buried with shells and traces, preserving through the fossilization barrier about 20% of the Anodonta traces. This bivalve activity is a useful tool to recognize preservation of mud in quiet environments and parallels ichnological evidence of unknown epich...

- by Paolo Monaco
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- Geology, Invertebrate Ichnology, Neoichnology
- by Alexander Parkinson and +1
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- Ichnology, Taphonomy, Termites, Neoichnology
- by Alexander Parkinson
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- Ichnology, Invertebrate Ichnology, Neoichnology

This paper characterizes the modern Psilonichnus ichnocoenosis present in the seaward side of Peixe Lagoon (southernmost Brazil) and discusses its preservation potential in the fossil record and its (paleo)environmental and stratigraphic significances. This ichnofauna occurs in exposed softgrounds and stiffgrounds of the backshore and backbarrier environments associated with the channel mouth area of the lagoon. The burrow assemblage is composed of Y- and J-shaped dwelling burrows and trackways of grapsid crabs (Chasmagnatus granulata), fiddler crabs (Uca uruguayensis), and
ocypodid crabs (Ocypode quadrata), tracks and trackways of scarab beetles, birds, and small lizards, horizontal, randomly branched, shallow feeding burrows of mole crickets, dwelling burrows of small rodents and ant nests. As a natural park, most of the natural environmental conditions that support the establishment of such an ichnocoenosis are preserved in the study area, favoring its use as a modern analogue to the ancient Psilonichnus Ichnofacies. Thus, original concepts developed after the first record of the Psilonichnus ichnocoenosis in modern environments, which supported the construction of the Psilonichnus Ichnofacies paradigm, are revisited herein and some premises are reinforced. Possible stratigraphic scenarios are also estimated, allowing the inference that the best preservation of the Psilonichnus Ichnofacies occurs during the establishment of transgressive system tracts.

- by Renata Netto
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- Sedimentology, Ichnology, Invertebrate Ichnology, Paleoecology
- by Paolo Monaco
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- Geology, Invertebrate Ichnology, Neoichnology

Barrier-islands are common landforms and biodiverse habitats, yet they received scarce neoichnological attention. This gap is tackled by studying the Mula di Muggia barrier-island system (Grado lagoon, Italy), focus-ing on morphology, ecology and ethology of individual traces. The following incipient ichnotaxa are Thalassinoides and 'squat burrows'. Vertebrate (Avipeda-/Ardeipeda-like, Canipeda) and invertebrate tracks ('parallel furrows') are also described. For each ichnotaxon, tracemaker and behavior are discussed, together with their position with respect to sediment barriers. Results suggest that sediment barriers impose a sharp contrast in terms of ichnological composition. Back-barrier is dominated by branched burrows (i.e. Thalassinoides, Parmaichnus), while the fore-barrier presents vertical and U-shaped burrows (Arenicolites, Skolithos). The environmental conditions of the back-barrier show that low-oxygen substrates favor intense bioturbation, provided that the water column is sufficiently oxygenated.

- by Andrea Baucon
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- Ichnology, Ecology/Chemistry of Shallow Lagoons, Neoichnology, Tidal Marsh Ecology

Neoichnological experiments involving a species of sand-swimming skink, Chalcides ocellatus, demonstrate the diversity of biogenic structures produced by desert-dwelling lizards. The skinks were placed into terrariums with ten, 1-cm-thick layers of fine-, medium-, or coarse-grained sand for periods of 7 to 14 days. Sediment moisture content was held constant at either 0% or 20%. The sand skinks exhibited locomotion, escape, and resting behaviors. They burrowed to a maximum depth of 4.2 cm with most activity restricted to the upper 2 cm of the sediment. The biogenic structures produced included surface mounds and depressions; layer truncations; surficial and subsurficial sinuous, bilobate trails; isolated-to-connected, U- to V-shaped divots; flame structures; and open burrows. The size and diversity of biogenic structures produced by C. ocellatus changed with variations in sediment grain size and moisture content. Biogenic structures tended to be better defined in fine-grained sand. The width of the isolated U- to V-shaped divots was greater in the medium- and coarse-grained sand. Connected U-to V-shaped divots only occurred in the dry, fine- and medium-grained sand whereas open burrows were only produced in moist sand. While engaged in sand swimming the skinks altered grain sorting, loosened the sediment fabric, increased porosity and permeability, and added organic matter in the form of food remnants, fecal material, and shed skin. Data collected in this study can be used to better interpret terrestrial trace fossil assemblages in arid, eolian paleoenvironments to better assess the paleoecology of these ancient settings.

- by Angeline Catena
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- Ichnology, Trace Fossils, Reptiles, Bioturbation

We performed a series of neoichnological experiments with elephants to investigate the relationship between the various factors involved in controlling megafaunal footprint formation. Our ultimate goal was to provide a means to calculate original sedimentary properties of fossilfootprint-bearing siliciclastic rocks, especially those containing sauropod dinosaur tracks. Previous semiquantitative and model-based research identified multiple variables that influence footprint creation and preservation, but no rigorous, empirically based models have been constructed. We conducted track-making trials with experimental sediments and one adult female African elephant (Loxodonta africana) and one adult female Asian elephant (Elephas maximus) in a zoo setting. Data collected included track dimensions, sediment particle size distribution, sediment bulk density (r b ), volumetric water content of the sediment (h v ), and trackmaker walking velocity (v) and weight. We performed multiple regression analysis with a backward elimination technique to obtain the following relationship:

- by Brian Platt
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- Vertebrate Ichnology, Neoichnology

- by Stephen Hasiotis
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- Evolutionary Biology, Geology, Vertebrate Ichnology, Ecology
- by Angeline Catena
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- Neoichnology, Continental Ichnology, Skinks
- by Eric Roberts
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- Evolutionary Biology, Geology, Ichnology, Invertebrate Ichnology

ICHNOFAUNA OF MODERN COASTAL DEPOSITS FROM SOUTHERN BRAZIL. With the objective of establishing the relationship between coastal deposits and ichnofacies, an ichnofauna from modern coastal environments of the Rio Grande do Sul State, southern Brazil, is analyzed herein. The seaward area of the Peixe Lagoon was choosen due its proximity to the sea. Y- and J-shaped burrows made by the crabs Chasmagnatus granulata and Uca uruguayensis (the later occupied by the crab Metasesarma rubripes) dominated the ichnocoenosis, followed by bird and other vertebrate trackways on the lagoon margins. Insect trails and burrows also occur, as well as ant galleries. Horizontal and vertical burrows of polychaetes, and resting and escape traces of Callinectes spidus dominate the benthic ichnocoenosis of the lagoon. Analogies between the ichnocoenosis of the Peixe Lagoon and the Psilonichnus ichnofacies provide information on the processes related to faunal distribution in coastal environments.

- by Renata Netto
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- Sedimentology, Ichnology, Invertebrate Ichnology, Vertebrate Ichnology