The Arcella gandalfi amoeba is a single-celled organism - which means each live amoeba is only composed of one cell. The amoeba's 'hat' is actually a shell known as a carapace.

Summit’s Arcella earns three-peat at MOCs, wins 200 freestyle in thrilling fashion Updated: Mar. 02, 2025, 8:03 p.m. | Published: Mar. 02, 2025, 2:39 p.m.