Composite of catalized reporter deposition fluorescence in situ hybridization (CARD-FISH) images showing the range of sizes of the different UCYN-A sublineages (left images: UCYN-A1 sublineage; middle images: UCYN-3 sublineage; right images: UCYN-A2 sublineage) and their symbiotic haptophyte partners. Images were taken under blue (green-labeled haptophytes with Alexa 488 stain) and green (red-labeled UCYN-A with Alexa 594 stain) excitation wavelengths (STAR Methods) (scale bar, 5 m). See also Figure S1.
