Greek aphis, snake, +glossa, tongue; the fertile spikes of some genera in this family suggest a snake's tongue.

Plants mostly small and fleshy, terrestrial, sometimes epiphytic. Rhizomes short and mostly subterranean, with fleshy roots. Blades simple or divided. Sporangia relatively large, opening by transverse slits, borne in two rows on fertile spikes arising from stipes, or from blades. Gametophytes subterranean.

Fronds of plants in this family do not grow by circinate vemation (by expansion and uncoiling of crosiers or fiddleheads).

A family of three or four genera and about eighty species in both tropical and temperate zones. Represented in Hawai'i by three genera with six species.