FAMILY PETRARCIDAE GRUVEL, 1905

Diagnosis: Endoparasitic in scleratinian corals. Carapace with two thick valves covered by spines and/ or papillae, without brood chamber. Antennules fivesegmented, not subchelate, with developed armament on distal segment. Mandibles and maxillules rarely unarmed and with short, cutting edge; distal parts of maxillae reduced. Thoracopods uniramous, with few or no setae; first pair absent or reduced. Enlarged abdominal segment 1. Simultaneous hermaphrodites.

Introcornia Grygier, 1983 (two species)

Petrarca Fowler, 1889 (eight species)

Zibrowia Grygier, 1985 (one species)