Idiosepiidae
Idiosepiidae is a family of bobtail squid belonging to the order Sepiida. It is a small family, containing only two genera, Idiosepius and Sepioloidea, and approximately 18 species. These small squid are found in the tropical and subtropical waters of the Indo-Pacific region, ranging from the Red Sea and East Africa to the Philippines and Australia.
Common Names
Idiosepiid squid are commonly known as bobtail squid or pygmy squid. The name "bobtail squid" refers to their short, rounded mantle, which is unlike the elongated mantle of most other squid species. "Pygmy squid" refers to their small size, with most species reaching only a few centimeters in length.
Characteristics
Idiosepiid squid share several key characteristics that distinguish them from other squid families. These include:
- Short, rounded mantle: This gives them their characteristic bobtail shape.
- Small size: Most species reach only a few centimeters in length, with some reaching up to 10 centimeters.
- Reduced fins: The fins are small and located near the posterior end of the mantle.
- Large eyes: The eyes are disproportionately large compared to their body size.
- Internal shell: They possess an internal shell, called a gladius, which is reduced and often poorly developed.
- Color-changing ability: Like most squid, they possess chromatophores and iridophores, allowing them to change color and patterns rapidly.
Environment
Idiosepiid squid are found in a variety of habitats, including coral reefs, seagrass beds, and sandy bottoms. They are primarily nocturnal, spending the day buried in the sediment or hiding among coral. They are also known to inhabit brackish waters, such as estuaries and mangroves.
References
* World Register of Marine Species * NCBI - A new species of pygmy squid, Idiosepius thailandensis sp. nov. (Cephalopoda: Sepiida: Idiosepiidae) from Thailand