Diagnosis. This is based on adult characters of separate lithocolletine genera following prior work (e.g., Stainton 1857; Chapman 1902; Ely 1918; Meyrick 1927; Le Marchand 1936; Kumata 1961, 1963, 1993; 1995; Vári 1961; Bradley et al. 1969; Kuznetzov 1981; Watkinson 1985; Davis & Robinson 1998; Parenti 2000; Bengtsson & Johansson 2011):
Hindwing with the vein Rs nearly parallel with vein M 1 or M 1+2 at the basal half of wing (Kumata 1993; Davis & Robinson 1998).
In addition to this hindwing venation character (Table 2; Figs 11–20), the following adult characters may also serve to separate the subfamily Lithocolletinae from the other subfamilies of Gracillariidae: i) tiny moths (less than 10 mm in wingspan), adults rest with body parallel to surface or with head end lowered; ii) background colour of forewing brilliantly ochreous, copper-golden, reddish-brownish, with white or silvery white striate, wedge-like markings, roundish spots, or brownish/black thin, lineal fascial and striate markings; iii) head tufted with longer or shorter occipital piliform scales; iv) labial palpus moderate, porrect or drooping straight, filiform, with approximate ratio of palpomeres from base 1:1:1.5 (Figs 5–10); v) forewing with seven to nine veins, CuP indistinct over entire length; vi) hindwing with five to six veins, M 1 indistinct at basal half; vii) eighth abdominal sternite of male modified, produced caudally, forming a flap laying under valvae except in Chrysaster, Leucanthiza, Macrosaccus, and Protolithocolletis.