Not just in South America sometimes an animal species, considered to be extinct, is rediscovered.
From Wildlife Extra:
Rare snail, thought to be extinct in the UK, found in Chichester
Lagoon Spire snail discovered in Chichester Conservancy
May 2011. Dr Martin Willing (a leading authority on molluscs) conducted a snail survey in autumn 2009 to locate the rare Desmoulin’s Whorl Snail (Vertigo moulinsiana) on a site where we undertook urgent management work to improve the site for this species in 2007.
A further survey was undertaken in spring 2010 in an attempt to re-locate the population, however, this again failed to locate the species. If the species is still present it is hoped that continued appropriate site management, will allow the population to grow to detectable levels.
Lagoon spire snail
However during the survey he found a population of Lagoon Spire snails (Heleobia stagnorum), which were thought to be extinct in the UK. The survey confirmed a strong population on a site in Chichester Harbour and provided a valuable insight into the ecological needs of this species. Lagoon Spire snails grow to just 5 millimetres long.
The species was supposedly extinct in England since Roman times.
Large ambersnail with parasitic flatworm; video here.