H I contours overlaid on DECaLS griz false-color images. Galaxies are ordered top-to-bottom, left-to-right as they appear in Table 1. Top row: CHILES galaxies detected in CO (1–0) by ALMA. H I column densities are 2ⁿ × [2.6, 2.1, 2.8, 1.8, 2.0]×10²⁰ cm⁻² (n = 0, 1, 2…). Middle and bottom row: CHILES galaxies that are undetected in CO (1–0). H I column densities are as above: 2ⁿ × [2.1, 3.2, 2.0, 1.8], and [1.8, 2.6, 1.7, 1.3]×10²⁰ cm⁻² (n = 0, 1, 2…). There is a clear dichotomy between the two sets of galaxies: CO detections are noticeably redder, while CO non-detections are significantly bluer. See text for discussion. Note that the top left-most galaxy (0969208) has a star superimposed to the north of the nucleus which appears white. The red area to the south of the star is from the background galaxy.