Common blanket octopus

Common blanket octopus
Scientific classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Cephalopoda
Order: Octopoda
Family: Tremoctopodidae
Genus: Tremoctopus
Species:
T. violaceus
Binomial name
Tremoctopus violaceus
Range of Tremoctopus violaceus
Synonyms
  • Octopus atlanticus
    D'Orbigny, 1834 in 1834–1847
  • Octopus gracilis
    Souleyet, 1852
  • Octopus koellikerii
    Verany, 1847
  • Octopus mycrostoma
    Reynaud, 1831
  • Octopus quoyanus
    D'Orbigny, 1834 in 1834–1847
  • Ocythoe velata
    Risso, 1854
  • Octopus velifer
    Ferussac, 1835 in 1834–1848
  • Tremoctopus joubini
    Hoyle, 1909
  • Tremoctopus lucifer
    Akimushkin, 1963
  • Tremoctopus microstomus
    (Reynaud, 1831)

The common blanket octopus or violet blanket octopus (Tremoctopus violaceus) is a large octopus of the family Tremoctopodidae found worldwide in the epipelagic zone of warm seas. The degree of sexual dimorphism in this species is very high, with females growing up to two meters in length, whereas males grow to about 2.4 cm. The first live specimen of a male was not seen until 2002 off the Great Barrier Reef. Individual weights of males and females differ by a factor of about 10,000 and potentially more.

Recent studies on the mitochondrial genome of Tremoctopus violaceus have provided insights into the species' phylogenetic relationships within the octopus family. The analysis suggests that Tremoctopus violaceus is closely related to other members of the Tremoctopodidae family (Dae-Ju et al., 2022).Males and small females of less than 7 cm have been reported to carry with them the tentacles of the Portuguese man o' war. It is speculated that these tentacles serve both as a defensive mechanism and possibly as a method of capturing prey. This mechanism is no longer useful at larger sizes, which may be why males of this species are so small. The web between the arms of the mature female octopus serves as a defensive measure as well, making the animal appear larger, and being easily detached if bitten into by a predator. The complete mitogenome of T. violaceus is a circular double-stranded DNA sequence that is 16,015 base-pairs long.