Is it too soon to suggest adding location codes like the killie folks do. It's possible they are different species. AZnd it's sounds equally plausable they are geographic variations of the same species. Since Mike's fish was collected by Julio, he should be in a possition to assign a collection code, which would differentiate it from the other specimin without infering too much into the relationship.
For example, I know some S.A. killie collectors use a country code in their naming, such as Autrolebias sp. CXCL004, as explained by Thomas Litz, _URUGUAY 1994: Not Only for Cynolebias _, AguaTropica2, Voulume 1, Number 4. 1995 (maybe 1996).
"The collection code the Uruguayan friends use, puts the first letters as the international code for Uruguay (CX), followed by the next letters which denote the State (here Cerro Lago, CL). The further code defines the membership in the Egg Laying Tooth Carp (0) and the sequence (01, 02.) the new kinds discovered in this district, which could be related to the described species. Since we work together as part of the AG Cynolebias, we have also for the newly caught and/or unknown kinds utilized this code. We hope to avoid the inscrutable confusion which is found in reference to the labels which are used in Africa "