Bombyx mori with the opportunity to witness the life cycle of silkworms. The practice of raising silkworms by children as pets has, in non-silk farming South Africa, led to the development of extremely hardy landraces of silkworms, because they are invariably subjected to hardships not encountered by commercially farmed members of the species. However, these worms, not being selectively bred as such, are possibly inferior in silk production and may exhibit other undesirable traits. The full genome of the silkworm was published in 2008 by the International Silkworm Genome Consortium. Draft sequences were published in 2004. The genome of the silkworm is
Crustacean larva (lecithotrophy). In species with normal development, eggs are roughly 1% of the size of the adult; in species with abbreviated development, and therefore more yolk in the eggs, the eggs may reach 1/9 of the adult's size. The post-larva of shrimp is called "parva", after the species "Acanthephyra parva" described by Henri Coutière, but which was later recognised as the larva of "Acanthephyra purpurea". In the marine lobsters, there are three larval stages, all similar in appearance. Freshwater crayfish embryos differ from those of other crustaceans in having 40 ectoteloblast cells, rather than around 19. The larvae show abbreviated development,