Checking a South American U-boat wreck claim

Which U-boat can reportedly be seen in a South American mangrove?

No particular wreck could be identified. A source link was requested so the claim could be investigated further.

No matching U-boat wreck could be found in the records consulted during the answer. Mangrove coastlines made the broad location plausible, but that did not identify a vessel. The uncertainty left open the possibility that a relevant case had been missed. A link to the claim would allow its vessel identity and location to be checked.