Idiosepius is a genus of squids in the family Idiosepiidae. Members of this genus are of no interest to commercial fisheries. Idiosepius are found primarily in tropical and temperate waters throughout the Indo-Pacific, often found in association with seagrass and mangrove roots. Pygmy squid brain structures and nervous system are comparable to other squids and octopuses but they have a more developed optical tract. The beaks of Idiosepius show small toothlike structures, a genus specific feature which can be useful in distinguishing Idiosepius species.
- Idiosepius hallami <small>Reid & Strugnell, 2018</small>
- Idiosepius kijimuna <small>Reid, Sato, Jolly & Strugnell, 2023</small>
- Idiosepius minimus <small>(d'Orbigny in Férussac & d'Orbigny, 1835)</small>
- Idiosepius paradoxus <small>(Ortmann, 1888)</small>
- Idiosepius picteti <small>(Joubin, 1894)</small>
- Idiosepius pygmaeus <small>Steenstrup, 1881</small>
Phylogeny
The major morphological characteristic that separates Idiosepius from other cephalopods is its adhesive organ. Molecular analysis has separated Idiosepius species into 4 clades A female has the ability to allocate more or less energy to reproductive tissues and the development of eggs depending on the season, which causes slower body growth but larger gonads during colder temperature spawning periods. There is less variation in spawning patterns among species, females either adhere upside down to a substrate to lay eggs, All species of Idiosepius, except I. thailandicus and I. minimus, hatch with tentacles. Once the buccal mass has been inserted, the squid releases cephalotoxin to paralyze the prey, and enzymes to externally digest the flesh.
References
Further reading
- von Boletzky, S., et al. 2005. Phuket mar. biol. Cent. Res. Bull. 66: 11–22.