Abstract
Introduction: The taphonomic attributes of a faunal assemblage provide information about which agents affect both, the distribution and preservation of ancient or newly-formed biogenic materials, during their depositional and post-depositional processes.
 Thus, actuotaphonomy is a valuable tool to the reconstruction of fossil communities, as it establishes analogies between observable processes in the present and those that happened in the past.
 Objective:The taphonomic attributes of a marginal marine environment were analyzed, in order to assess the origin of fragmentation, bioerosion and incrustation processes and the role of these characteristics in the deterioration of current sediment accumulations of mollusks (gastropods and bivalves), to generate an actuotaphonomic model that could be applyable to analogous ecosystems to Laguna de Mandinga (Mandinga Lagoon), in Veracruz, Mexico.
 Methods: The material came from a shell-remain accumulation called "El Conchal". A batch of 1,697.9 g was processed, selecting 1,165 complete specimens, of which 5 genera of bivalves and 4 genera of gastropods were identified. Results: The taphonomic analysis showed that fragmentation and bioerosion have a medium attribute, which may be due to energy, constant rework and exhumation of the remains at the lagoon's water-sediment interface; three biogeneous agents were identified: Entobia isp, Oichnus and Caulostrepsi, being Caulostrepsi the less abundant. The incrustation showed of poor degree since the ecosystem intrinsic conditions did not allow many encrusting organisms to grow properly, however, these organisms are represented by calcareous tubes of serpulid polychaetes, bryozoans with calcareous skeleton and barnacles.
Highlights
The taphonomic attributes of a faunal assemblage provide information about which agents affect the distribution and preservation of ancient or newly formed biogenic materials during depositional and post-depositional processes
We identified four gastropod genera (N = 173): Bailya Smith, 1944; Cerithideopsis Thiele, 1929; Nassarius Duméril, 1805; and Neritina Lamarck, 1816 (Fig. 2)
Among the bioeroding organisms found in the sample, three types of perforations were identified related respectively to ichnogenus Entobia Bronn, 1937; Caulostrepsis Clarke, 1908; and Oichnus Bromley, 1981
Summary
The taphonomic attributes of a faunal assemblage provide information about which agents affect the distribution and preservation of ancient or newly formed biogenic materials during depositional and post-depositional processes. Objective: The taphonomic attributes of a marginal marine environment were analyzed to assess the origin of fragmentation, bioerosion, and encrustation processes and the role of these characteristics in the deterioration of current sediment accumulations of mollusks (gastropods and bivalves). The fragmentation and bioerosion were classified as regular (grade 1), this may be the results of the water energy in the environment, that permits a constant rework, and exhumation of the remains at the lagoon’s water-sediment interface; three eroders were identified to ichnogenus level: Entobia, Oichnus, and Caulostrepsis, being Caulostrepsis the least abundant. Conclusions: In marine marginal environments as in lagoon areas the encrustation does not have an important role in the preservation or destruction of shelly assemblages, being taphonomically more important than fragmentation and bioerosion as potentially destructive agents that can be a source of loss of fidelity in the fossil record
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
