Sepia (cephalopod)
A genus of cuttlefish with ellipsoid cuttlebone and retractable tentacles.
Sepia is a genus within the cuttlefish family Sepiidae, and it includes many of the most familiar and widespread species. The genus name comes from the Latinized version of the Ancient Greek word σηπία (sēpía), which means "cuttlefish."
**Anatomy** Every member of Sepia has eight arms and two tentacles. The tentacles are retractable and are used to target and grab prey, while the arms handle the prey and create patterns of light and dark to confuse it. Once the prey is caught, the tentacles release from it and serve no further purpose. These tentacles are stored in sheaths that run beneath the eyes and behind the head, extending into the visceral mass, where they are kept coiled like springs, ready to shoot out toward food.
**Classification** A 2023 study made major changes to the makeup of the genus Sepia. As a result, many species were moved out of Sepia and placed into revived genera or raised from subgenera. According to WoRMS, the genus now contains 58 species, though some still need confirmation. The species marked with an asterisk (*) were examined in the 2023 paper.
**Extinct species** Several extinct species have been described from Europe’s Neogene period, though many are probably synonyms. These include: Sepia bertii Foresti, 1890 Sepia complanata Bellardi, 1872 Sepia craversii Gastaldi, 1868 Sepia gastaldii Bellardi, 1872 Sepia granosa Bellardi, 1872 Sepia harmati Szörenyi, 1933 Sepia hungarica Lörenthey, 1898 Sepia isseli Bellardi, 1872 Sepia michelotti Gastaldi, 1868 Sepia rugulosa Bellardi, 1872 Sepia stricta Bellardi, 1872 Sepia verrucosa Bellardi, 1872 Sepia vindobonensis Schloenbach, 1869
**References** Mangold, Katharina M.; Young, Richard E. (2016) [10 November 2012]. "Sepia". Tree of Life web project (tolweb.org). Retrieved 28 August 2023.
Quick Facts
- Taxon
- Sepia
- Type Species
- Sepia officinalis
- Type Species Authority
- Linnaeus, 1758
Facts from the source article.
Lore & Background
All members of Sepia possess eight arms and two tentacles. Tentacles are retractable limbs used to target and latch onto prey, whereas arms are used for handling prey and producing patterns of light and dark to distract prey. Once a prey item has been caught, the tentacles detach from it and have no other function. The tentacles reside in sheaths that run below the eyes and behind the head, into the visceral mass, where they are reserved as coiled, spring-loaded appendages, waiting to be ejected towards a food target.
A 2023 paper extensively revised the composition of genus Sepia; as a consequence, many species have been split out of genus Sepia, assigned to revived genera or elevated subgenera. Currently, the genus has 58 species, according to WoRMS. A number of these species need further verification. A list of extinct species has been described from the Neogene of Europe, though many of these are likely synonyms.
Reader's Guide
The genus Sepia is notable for including some of the best known and most common cuttlefish species. Its cuttlebone is ellipsoid in shape. The genus name derives from the Ancient Greek word for cuttlefish. The anatomy of Sepia is distinctive: members possess eight arms and two retractable tentacles, the latter used solely for targeting and latching onto prey, after which they detach and have no further function. The tentacles are stored in sheaths running below the eyes and behind the head into the visceral mass, coiled like springs ready to eject. The arms handle prey and produce light-and-dark patterns to distract prey. In 2023, a major revision split many species out of Sepia into revived genera or elevated subgenera, leaving 58 species according to WoRMS, though some require further verification. Extinct species have been described from the Neogene of Europe, but many are considered likely synonyms. The genus thus represents a core group within cuttlefish taxonomy, with ongoing refinement of its composition.
Did You Know?
- The name Sepia is the Latinised form of the Ancient Greek σηπία (sēpía) meaning 'cuttlefish'.
- All members of Sepia have eight arms and two retractable tentacles.
- The tentacles detach from prey after capture and have no other function.
- A 2023 paper extensively revised the genus, splitting many species into revived genera or elevated subgenera.
More in Reef Cephalopods, Part 2 1-24
Spotted an error? Know more?
Reader corrections go straight into our review queue. Suggest an edit · How this site is sourced