Shellfish Breeding and Hatchery Management (2+1)

7.1.4. Identification of larval stages of crabs (Scylla serrata)

Larval stages	Important morphological characters
Zoea I	Eyes sessile ; 5 abdominal segments; telson with 3 + 3 spines.
Zoea II	Eyes stalked ; 5 abdominal segments; telson with 4 + 4 spines.
Zoea III	6 abdominal segments
Zoea IV	Rudiments of remaining thoracic appendages, abdominal segments with buds of pleopod.
Zoea V	Remaining thoracic appendages developed; pleopods on abdominal segments with setae; telson with 5 + 5 spines.
Megalopa	Carapace longer than wider; abdomen with 5 pairs of pleopods ; a pair of cheliped; 4 pairs of legs.
First crab instar	Carapace with 9 anterolateral teeth on either side; 3 pairs of walking legs; last pair of legs with paddle shaped dactylus; resembles parent.