In the laboratory the terrestrial tetanocerine fly Antichaeta testacea Melander completes its life cycle in 35 to 44 days. The female fly oviposits only on the egg clusters of its snail host. Instar I feeds only on snail eggs. Instars II and III also feed extensively on snail eggs besides attacking certain aquatic snails of the families Physidae and Lymnaeidae, but all instars are reluctant to attack adult terrestrial snails in the Succineidae. However, in southern California, because of their distribution, seasonal occurrence, and placement, the eggs of the succineid snails—mainly those of Oxyloma sillimani Bland—are considered to be the preferred hosts of ovipositing adults and first-instar larvae of Antichaeta testacea.

The female fly can lay 10 eggs daily for more than 50 consecutive days. During its development in the laboratory, a single larva can consume an average of 306 eggs of Physa virgata Gould or 113 eggs of Succinea californiensis Fischer and Crosse. Pupation occurs in the substrate, and some pupae enter a probable summer diapause, which may persist in certain individuals for more than six months.

Biosystematic criteria which suggest phylogenetic affiliation with the subfamily Sciomyzinae are: reticulate egg chorion; larvae which possess ventral spinule bands; a dorsal bridge which connects the pharyngeal sclerites; a “window” which occurs in the ventral cornua of the cephalopharyngeal skeleton; and the first-instar larvae, which are markedly obligate predators. Characteristics possibly unique among sciomyzid larvae possessed by Antichaeta larvae are the pubescent-appearing third-instar larva and adnation of the pharyngeal and hypostomal sclerites in all larval instars.