Ocorrência da Icnoespécie Nihilichnus nihilicus Mikulás, Kadlecová, Fejfar & Dvorák (2006) em Vértebra de Crocodylia da Formação Solimões (Mioceno Superior da Bacia do Acre)

Ichnological aspects related to bone substrate of fossil vertebrates of the upper Miocene Solimões Formation (Acre Basin) are still poorly understood. A recent taphonomic survey of fossils recovered from this unit and housed at the paleontological collection of Museu de Ciências da Terra da Companhia de Pesquisa de Recursos Minerais (MCT/ CPRM) revealed a vertebra of Crocodylia with a biogenic feature. This work describes this trace fossil and provides its ichnotaxonomic characterization, associating it with a possible tracemaker. The ichnoespecies Nihilichnus nihilicus is reported for the first time for the Solimões Formation, corresponding to a trace fossil observed in a posterior dorsal vertebra of a large Crocodylia. Purussaurus is the probable tracemaker, however, it is not possible to discern if the genesis of the ichnofossil is related to either predation or scavenging.