1,721,124 research outputs found
AIMS GEOSCIENCES
No full textAIMS Geosciences is a new international scientific Open Access journal dedicated to publishing peer-reviewed, high quality and innovative scientific research in all major geosciences disciplines including underlying processes. We publish the following article types: original research articles, letters, reviews, special issues, and editorials
Bollettino Malacologico
No full textLo scopo del Bollettino Malacologico è la divulgazione di tutti gli aspetti della malacologia attraverso la pubblicazione di articoli originali, note brevi e monografie riguardanti la tassonomia, l’ecologia e la biodiversità di molluschi sia viventi che fossili. Sono accettati lavori scritti in Italiano, Inglese, Francese e Spagnol
The genus Haedropleura (Neogastropoda, Toxoglossa = Conoidea) in the Plio – Quaternary of the Mediterranean basin
No full textScarponi, Daniele, Bella, Giano Della, Ceregato, Alessandro (2011): The genus Haedropleura (Neogastropoda, Toxoglossa = Conoidea) in the Plio – Quaternary of the Mediterranean basin. Zootaxa 2796: 37-55, DOI: 10.5281/zenodo.20656
Haedropleura Monterosato
No full textGenus <i>Haedropleura</i> Monterosato in Bucquoy, Dautzenberg & Dollfus, 1883 <p> Type species (s.d.) <i>Murex septangularis</i> Montagu, 1803</p>Published as part of <i>Scarponi, Daniele, Bella, Giano Della & Ceregato, Alessandro, 2011, The genus Haedropleura (Neogastropoda, Toxoglossa = Conoidea) in the Plio – Quaternary of the Mediterranean basin, pp. 37-55 in Zootaxa 2796</i> on page 39, DOI: <a href="http://zenodo.org/record/206562">10.5281/zenodo.206562</a>
THE TRACE FOSSIL RECORD OF TREMATODE-BIVALVE PARASITE-HOST INTERACTIONS
No full textParasitism is one of the most pervasive phenomena amongst modern eukaryotic life and yet, relative to other biotic interactions, very little is known about its history in deep time. As many parasites are small-bodied and lack biomineralized skeletons, we should not expect an extensive record of body fossils, therefore we must also seek evidence for parasitism in the form of traces and malformations on the mineralized hosts. Digenean trematodes (Platyhelminthes) are complex life cycle parasites, which have practically no body fossil record, but induce the growth of characteristic malformations in the shells of their bivalve hosts. Many of these malformations are readily preserved in the fossil record, but, until recently, have largely been overlooked by students of the fossil record. In this talk, we present the various malformations induced by trematodes in living bivalves, evaluate the distribution of these traces through deep time in the phylogenetic and ecological contexts of their bivalve hosts, explore how various taphonomic processes have likely biased our understanding of trematodes in deep time, and evaluate their utility as paleoenvironmental indicators. Trematodes are known to negatively affect their bivalve hosts in a number of ways including castration, modifying growth rates, causing immobilization and, in some cases, altering host behavior making the host more susceptible to their own predators. Digeneans are expected to be significant agents of natural selection. To that end, we discuss how bivalves may have adapted to their parasites via heterochrony. Additionally we will explore how the fossil record of trematodes can inform our predictions for shallow marine and estuarine ecosystems in the context of anthropogenic climate change and sea level rise
Bela pseudoappeliusi n. sp. (Neogastropoda: Mangeliidae) from the Plio-Pleistocene of Italy
No full textABSTRACT - A new species of mangeliid, Bela pseudoappeliusi (Neogastropoda, Conoidea), is described from the Plio-Pleistocene of
Italy. The systematic description is based on a series of eleven specimens selected from the numerous findings in northern and central Italy
(Piedmont, Emilia-Romagna, Tuscany and Lazio). The new species shows affinities to Bela (s.l.) appeliusi (Bellardi, 1877) with regard to
particular features such as shell dimension, teleoconch sculpture and aperture morphology. The study includes a detailed survey of the type
locality as well as a brief account of occurrences at other localities
Paleoecological Implications of Trematode-Induced Pit Size in Chamelea Gallina from the Adriatic Sea, Italy
No full textnon present
I Molluschi marini del Plio-Pleistocene dell'Emilia-Romagna e della Toscana. Superfamiglia Conoidea. Mangeliidae - Vol. 4 - Conidae II.
No full textLa classificazione dei taxa plio-pleistocenici della famiglia Mangeliidae è da sempre un argomento difficile, che si presta a controverse interpretazioni.
Gli autori, come nei precedenti volumi, hanno posto alla base delle loro analisi il reperimento dei tipi e le loro definizioni originali, pietre miliari della ricerca tassonomica. Questo approccio ha permesso di verificare,
ad esempio, come alcune specie siano definite da serie tipo ormai scomparse e da descrizioni non sufficienti a caratterizzarle. Gli autori, in questi casi, hanno determinato gli esemplari studiati sulla base dell’iconografia
(quando possibile dei tipi) e delle pubblicazioni successive, pur con il beneficio del dubbio, esteso anche a tutte le citazioni precedenti della specie, che suggerisce la necessità di reperire dei topotipi e designare un neotipo.
Questi casi documentano la serietà della loro revisione (vedi nota dei curatori
del vol. 1). Nella determinazione degli esemplari fossili gli autori hanno preso in considerazione
anche i taxa attuali del Mediterraneo con relative problematiche tassonomiche, condizione indispensabile per affrontare la classificazione e la determinazione delle specie plio-pleistoceniche. Può essere motivo di
discussione l’elevato numero di nuove specie proposto; ma negli studi sulla biodiversità è più opportuno segnalare nuovi taxa che trascurarne le peculiarità ed affossarne forse per sempre la possibilità di una distinzione. Saranno le ricerche future che decreteranno la validità o meno di queste nuove
specie. La classificazione e la determinazione dei Conoidea hanno sempre rappresentato
uno scoglio notevole e come conseguenza la loro utilizzazione per analisi biogeografiche e/o sulla biodiversità è sempre stata limitata. In letteratura infatti sono stati prevalentemente utilizzati gruppi con classificazioni
più consolidate (ad esempio i bivalvi) e quindi con distribuzioni stratigrafiche, biogeografiche ed ecologiche più affidabili. Vorremmo ricordare, concludendo, che l’obiettivo di partenza degli autori era proprio quello di fornire un contributo alla possibilità di utilizzare correntemente questo taxon per analisi biogeografiche e paleoecologiche nel Plio-Pleistocene
Trematode-Bivalve interaction in regressive back-barrier settings of the Po Plain (Italy).
No full textElucidating the history of biotic interactions in the fossil record has been a primary theme in paleobiology during the last decades. The majority of this pursuit has been the examination of the activities of predators, and has highlighted the likely role of antagonistic interactions in shaping macroevolutionary trends. However, the role of parasite-host interactions in deep time has not received comparable systematic treatment. Parasitism is one of the most pervasive phenomena amongst modern eukaryotic life and, by contrast, only a minority of studies are known about it in deep time. Here, looking for trematode induced pits, we surveyed >3,000 valves from cored Holocene back-barrier (freshwater to brackish) regressive deposits of the south-eastern Po coastal plain (Northern Italy). The results are contrasted against previous investigations that focused on more distal, shallow marine (shoreface to offshore transition) deposits from the same area. As in previously (and more distally) investigated deposits, preliminary results indicate that digenean trematodes are selective parasites in terms of host taxonomy and host body size. Indeed the bulk of trematode traces were recovered in Abra segmentum: a shallow infaunal siphonate bivalve. Furthermore, as in previous investigations, trematode distribution was environmentally restricted, primarily recovered in lagoonal paleoenvironments with a peak in inner lagoonal settings. Trematode prevalence is higher in lagoonal settings than in lower shoreface settings. Such studies of trematodes prevalence and its millennial scale dynamics are also of basic importance to providing a reference system for evaluating severity and significance of anthropogenic changes in such environments
- …
