Alejandro Biain — Chascomús, Province of Buenos Aires

Official source account — 2021 annual report, printed page 79: Alejandro Biain discovered an oval shape when reviewing a photograph from Chascomús. CIAE identified a rounded translucent projection extending obliquely from the body, consistent with an insect wing. The combination of apparent anatomy and strong closeness to the lens supported a nearby flying insect. The agency classified this explanation Type B, with no contemporaneous sighting or reproducible passage available. The summaries distinguish reported observations from the agency’s proposed explanations. Source Type A/B ratings describe explanatory confidence and are not encounter classes. The map uses an approximate GeoNames locality centroid, not the observation point.