''Euprymna berryi'', commonly called hummingbird bobtail squid or Berry's bobtail squid among various other vernacular names, is a

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

mollusc Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is esti ...

cephalopod A cephalopod is any member of the molluscan class Cephalopoda (Greek plural , ; "head-feet") such as a squid, octopus, cuttlefish, or nautilus. These exclusively marine animals are characterized by bilateral body symmetry, a prominent head ...

in the

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Sepiolidae Sepiolidae is a family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its me ...

Description

The hummingbird bobtail squid is a small sized

sepia Sepia may refer to: Biology * ''Sepia'' (genus), a genus of cuttlefish Color * Sepia (color), a reddish-brown color * Sepia tone, a photography technique Music * ''Sepia'', a 2001 album by Coco Mbassi * ''Sepia'' (album) by Yu Takahashi * " ...

. Its size varies according to the sex; males are no bigger than while the female reaches length. The global body aspect is compact and rounded. It possesses eight arms and two

tentacles In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work main ...

, a pair of small lateral

fins A fin is a thin component or appendage attached to a larger body or structure. Fins typically function as foils that produce lift or thrust, or provide the ability to steer or stabilize motion while traveling in water, air, or other fluids. Fin ...

on the posterior part of the mantle. The background color of the body is translucent with a large number of tiny dark

chromatophores Chromatophores are cells that produce color, of which many types are Biological pigment, pigment-containing cells, or groups of cells, found in a wide range of animals including amphibians, fish, reptiles, crustaceans and cephalopods. Mammals and ...

. The chromatophores are widely distributed over all of the body including the arms, head, ventral and dorsal areas of the mantle, except the tentacles and the pair of lateral fins of which only the border with the mantle has

. The external color of the

, as we see it, is like a blend of small dark, electric blue and green dots.

Distribution & habitat

The hummingbird bobtail squid is widespread throughout the

tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

waters of the central

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

area from

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

to the

Philippines The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

. It is also possible that a larger distribution could reach the

Andaman Islands The Andaman Islands () are an archipelago in the northeastern Indian Ocean about southwest off the coasts of Myanmar's Ayeyarwady Region. Together with the Nicobar Islands to their south, the Andamans serve as a maritime boundary between th ...

Sri Lanka Sri Lanka (, ; si, ශ්‍රී ලංකා, Śrī Laṅkā, translit-std=ISO (); ta, இலங்கை, Ilaṅkai, translit-std=ISO ()), formerly known as Ceylon and officially the Democratic Socialist Republic of Sri Lanka, is an ...

and the western coast of

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

(some specimens were collected by scientists in 200-/2007). ''Euprymna berryi'' occupies the

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...

layer, as it prefers sandy or fine sediments seafloors in which it can easily bury itself in case of danger or to rest in during the day.

Biology

The hummingbird bobtail squid demonstrates nocturnal activity, and during daytime it usually stays buried in its preferred substrate. To hunt its prey at night, it uses a

bioluminescent Bioluminescence is the production and emission of light by living organisms. It is a form of chemiluminescence. Bioluminescence occurs widely in marine vertebrates and invertebrates, as well as in some Fungus, fungi, microorganisms including ...

organ located in the

gill A gill () is a respiratory organ that many aquatic organisms use to extract dissolved oxygen from water and to excrete carbon dioxide. The gills of some species, such as hermit crabs, have adapted to allow respiration on land provided they are ...

cavity which just emits enough light not to reveal its silhouette to potential predators. It feeds on mainly small benthic crustaceans.Norman, M.D. 2003. Cephalopods A World Guide. ConchBooks, Hackenheim, Germany.

References

External links

WORMS
* {{Taxonbar, from=Q2103308 Molluscs described in 1929 Bobtail squid