Erineum-gall
Guides
Acalitus ferrugineum
beech erineum mite
Acalitus ferrugineum is a microscopic eriophyid mite that induces erineum galls on the leaves of American beech (Fagus grandifolia). The galls appear as pale to light yellow patches that progress to reddish-brown later in the season. The species is known from the United States and Canada and has been documented in over 4,000 observations.
Aceria aceris
maple gall mite, maple erineum mite
Aceria aceris is a gall-forming eriophyid mite that infests maple species (Acer), producing distinctive erineum galls on leaf surfaces. The mite has a worm-like, elongated body with four legs and annular ridges typical of the superfamily Eriophyoidea. It is one of numerous Aceria species specialized on maple hosts, with populations often associated with specific maple species or varieties.
Aceria elongata
Crimson Erineum Mite
Aceria elongata, commonly known as the crimson erineum mite, is an eriophyid mite that induces distinctive erineum galls on the upper leaf surfaces of sugar maple (Acer saccharum). The galls progress from pale greenish patches to rich red-purple coloration as the season advances. This microscopic, worm-like mite has two alternating generations per year and is known from the eastern coast of the United States and Canada. At high densities, it can cause leaf distortion and premature leaf drop, though damage is generally not severe enough to require control measures.