Hirstithrombium noemiae Feider, 1955, representing one of the eight genera currently assigned to Johnstonianinae, is redescribed based on field-collected adults, deutonymphs and larvae, and also larvae obtained at the laboratory from field-born females. The species is associated with hygric habitats located at higher altitudes. A successful rearing allowed the first matching of heteromorphic instars within the genus known hitherto exclusively from active postlarval forms. A comparison of genera of Johnstonianinae, including species known from larvae and/or active postlarval forms is provided, species presently assigned to subfamily are listed and the key characters used in species diagnosing are discussed. A female of Hirstithrombium noemiae Feider, 1955 collected in Turkey is designated as neotype.