The genus Trichiorhyssemus contains 33 species, but only one species, T. riparius, is present in the United States. While very little is known about the biology of this species, its known distribution includes southern California, Las Vegas, NV, central and southern Arizona, and north-central New Mexico. Here, we report on the collection of T. riparius from Salt Creek Canyon, Canyonlands National Park in southeastern Utah USA, and its spatial and temporal distribution within the canyon. Collection methods included a combination of pitfall, window, and colored bowl traps. Our results indicate that 1) T. riparius is primarily a ground active beetle, 2) T. riparius forms strongly aggregated distributions at multiple scales, 3) T. riparius adults are abundant and/or active from April through June, but persist at low abundance and/or activity later in the summer and 4) T. riparius is the most abundant scarab and one of the most abundant beetles in samples from Salt Creek Canyon. To our knowledge, this is the first report of T. riparius in UT and extends its range well north of the Grand Canyon and far into the Colorado Plateau ecoregion.