|A dumbo Octopus|
The Umbrella Octopus are a group of octopus that frequent the open ocean (pelagic). As their name implies, they are best known for their manner of swimming through open water with their body flared like an umbrella. They are assigned to the taxonomic family Opisthoteuthidae, which contains four genera. The type genus of this family is the Opisthoteuthis, which includes the Flapjack Octopus also named for its behavior of flattening itself like a "pancake".
The Flapjack Octopus is given it's name, because of it's shape. (This kind of octopus is very oval-shaped). It is also commonly known as a Pancake Devilfish. Some features include 1 or 2 fields of large suckers (for male octopus).This characteristic is present in the arms of the (male) octopus. They also, may have small fins. The 'Flapjack' octopus (or Pancake devilfish) commonly has, a U-shaped shell. The wing is sometimes classified as simple or a pointed cone. The shell can expand between walls that rise toward the tips. However, they do not have tooth-like structures in the sucker joint. The Flapjack octopus's head has large eyes. Again, in the head a few bundles of optic tract penetrate white body. The fins of a Flapjack octopus are not very large unlike their eyes, they are about a half mantle in width.
All of the arms of the Calypso Octopus are comparable. In the female octopus the seventh sucker is largest in a full grown male or female there are about 47-58 suckers, on each arm. Males have two fields of arms with bigger suckers that go beyond the others. The Proximal field with larger suckers only on arms III, and there are arms that are a little bit augmented which are the suckers IV. Sucker seven is the largest sucker. There are some Distal field with very big suckers on all arms but a little bit larger on arms III and IV. The suckers that are enlarged is 2-3 (hardly 4) that lie between sucker positions 23-29 the largest sucker in this set would be sucker 26. The Cirri has maximal length of 5 mm in a large octopods. The first cirrus is found between 1 and 2. In this type of octopus the male is dominant in size versus the woman. 
The species of the genus Grimpoteuthis are called a 'Dumbo Octopus' because of the fins (which look like ears) that project from the top of their head-shaped bodies. The reason for the name was the Walt Disney character DUMBO with big ears. The Dumbo Octopus's arms are described as follows: arms I(approximately 55 suckers) and arms II are a bit longer than arm III and IV. There are thirty suckers within the web.
They have tips of the arms that have 15 through 20 closely tightened suckers. The largest suckers are at basal a third of the arm which would be 2.5 mm diam. In this type of octopus the arms near the mouth are quite reduced and smaller in size compared to others.The basal third suckers (of the lateral arms) can be alternate. The Cirri is short at a distance of(3-4 mm). It has small scale eyes, which are measured at a 12 mm diameter.
The color of the body is simply translucent and is quite dull, however the fins are a dark brown and get darker as you move towards the tips. The oral surfaces of the arms and web are brown with a tint of purple. The suckers on these arms and webs are brown, but have a hint of yellow. 
Matured Opisthoteuthis calypso males, have spermatophores in their reproductive tract. In the mature females, Oviducal eggs can be from sizes 5.1 to 7.5 mm. The study of the ovarian oocyte size frequency is persistent in the continuous egg production and release. It is proposed that a single, extended, and continuous period of egg maturation and spawning exist in O. calypso, as suspected for most cirrate octopods. The males as well as females are contrasted in their suckers as well as their size and weight. The females lay eggs constantly, (unlike some animals they do not have breeding seasons).
Ecology is the scientific study of the distribution and abundance of life and the interactions between organisms and their natural environment. All organisms have certain requirements that need to be met for them to be able to carry on life. Ecology is the branch of biology dealing with the relations and interactions between organisms and their environment, including other organisms. To avoid being prey, the octopus selects and changes in the substratum, where it remains most of the time, especially during daylight hours. The Opisthoteuthis grimaldii Octopus is found in the Bahamas.  They are sea floor creatures who live at extreme depths (3000-4000 meters). They can also 'turn on/off' their transparency. They hover above the sea floor, searching for worms, bivalves, pelagic copepods, and other crustaceans. This type of Octopoda species is quite rare. The typical location of the Grimpoteuthis Octopus is, 37°35'N, 71°18.8'W, 2,000 m depth.
An octopus's key mechanism to defense is camouflaging itself. An octopus usually has 3 colors in its skin cells (some can have up to four) to change its color. The camouflage of an octopus is very essential for not only one specific octopus because it can affect the rest by warning them of danger. As well as camouflaging itself as an octopus from its predators. An octopus relies upon its skin cells, for survival because it can not only change its color but its texture to match up with seaweed or coral etc. Octopuses have several secondary defenses (defenses they use once they have been seen by a predator). The second way the octopus defend itself is by its ink sack, which it releases as a cloud (this ink is melanin). This ink is simply useful concealing the octopus so it ca get away quickly and safely. Some octopus, for example the Mimic Octopus, can mimic other animals and change its color and texture closer to theirs (animals like lionfish, sea snakes, and eels).
- Opisthoteuthis Villanueva, Roger, Richard E. Young, and Michael Vecchione, Tree of life project, 28/04/2008.
- Opisthoteuthis agassizii Richard Younge/Michael Vecchione/Roger Villanueva, Tree of Life project, 2002.
- Opisthoteuthis calypso Villanueva, Roger, Richard E. Young, and Michael Vecchione, Tree life project, 17/07/2006.
- Den ecology of Octopus Vulgarus Cuvier Katsanevakis, Verriopoulos, Scientia Marina, 1997.
- Grimpoteuthis unknown, Bay Science Foundation, 16/02/2009.
- Octopoda: Grimpoteuthidae Collins, Martin, Wiley Interscience, 2003.
- Octopoda by ZipcodeZoo. BayScience Foundation, 19/01/2009.
- Octopus unknown, Wikipedia.org, unknown.