The larval descriptions of Xestia kolymae (Herz, 1903) and of two subspecies of X. lorezi: X. l. lorezi (Staudinger, 1891) and X. I. ogilviana Lafontaine, 1987, are given. Both holarctic species belong to the subgenus Pachnobia Guenée, 1852 sensu Lafontaine et al. (1987) and are compared with the larvae of X. tecta (Hübner, 1808) and X. I. kongsvoldensis (Grönlien, 1922). Drawings of hypopharyngeal complexes, mandibles and labra as well as illustrations of larvae are presented. Notes of chaetotaxy are given as ratios of setal distances. Large geographical variation of morphology, chaetotaxy and ornamentation of X. lorezi is tabulated and discussed. Mouthparts of larvae of the subgenus Pachnobia are preliminarily discussed with some larvae of related subgenera Schoyenia Aurivillius, 1883 and Anomogyna Staudinger, 1871.