Four Holarctic mirids—Cyrtorhinus caricis (Fallén) (Orthotylinae), Teratocoris caricis Kirkaldy (Mirinae), Tytthus pubescens (Knight), and Tytthus pygmaeus (Zetterstedt) (Phylinae)—are associated with Northwest Territory sedge, Carex utriculata, in Valles Caldera National Preserve in north-central New Mexico. Records of these plant bugs are the first for New Mexico and southernmost in the United States. The species are univoltine and overwinter as eggs, with those of C. caricis and Teratocoris caricis hatching in early to mid-May; eggs of the delphacid predators Tytthus pubescens and T. pygmaeus might hatch later. A syntopic delphacid, Nothodelphax venusta (Beamer), probably serves as prey of Tytthus species, as well as C. caricis, a facultative predator of Delphacidae. The four Holarctic mirids are considered relictual in the Jemez Mountains (Southern Rocky Mountains Ecoregion) rather than post-Pleistocene colonists. Color photographs of the adult dorsal habitus of a male and female of C. caricis, Teratocoris caricis, and Tytthus pubescens are included.