Sepia officinalis: A new biological model for eco-evo-devo studies
Yann Bassaglia, Auxane Buresi,Delphine Franko,Aude Andouche,Sébastien Baratte,Laure Bonnaud
Paper gives a good description of the officinalis cuttlefish and egg development and would be helpful to anyone raising an egg.
Yann Bassaglia, Auxane Buresi,Delphine Franko,Aude Andouche,Sébastien Baratte,Laure Bonnaud
Paper gives a good description of the officinalis cuttlefish and egg development and would be helpful to anyone raising an egg.
2.1. Development and organogenesis The life span of S. officinalis does not exceed two years. Females undergo just one reproductive round and die shortly after. In the field, eggs are laid near the coast in spring. Particularly, in the English Channel and Atlantic Ocean, they may be exposed to air and/or desalinated rainwater due to daily tides. Eggs are attached in batches and surrounded by thick black gelatinous envelopes (capsule) potentially protecting the embryo from environmental aggressions.
The development of all cephalopods, including S. officinalis, is direct: the adult bauplan is achieved with neither visible larval stage nor metamorphosis event within the egg capsule (Boletzky, 2006). After 34 weeks (at 25 °C in the laboratory), a young cuttlefish hatches and promptly adopts the adult necto-benthic mode of life (Fig. 1, left). Within the egg capsule the zygote cleavage gives rise to a disk-shaped embryo at the animal pole of the telolecithal egg, whereas the vegetal pole shows a thin layer of extra-embryonic ectoderm cells that cover the yolk. The first organs start delineating when the animal pole is shaped as a disk (from stages 15 to 19, based on Lemaire's system, 1970). The arms and mouth are located at the periphery while the mantle is central (Fig. 1A, left). Then, the embryo expands (stages 19 to 21) and the future adult antero-posterior axis clearly appears (stage 22 to hatching) as the mantle and the whole visceral mass tip out while the arm crown and the head still face the yolk mass (Fig 1A, right).