Octopodidae Family of Octopuses

Six Octopi of the Octopodidae Family can be found in this website:

Phylogeny: Benthic Octopuses are in the Mollusca phylum and in the Cephalopoda class and Octopodidae Family. This class includes squids, octopuses, cuttlefish, and nautiloids. Cephalopods are characterized by having a mantle (body), a head, and a foot that is modified into a series of, at least, eight arms. The arms attach to the head and surround the mouth. The arms may be equipped with suckers, hooks, or cirri. Some will have tentacles in addition to their arms. All cephalopods have three hearts. Two hearts pump blood to the gills, and one heart pumps blood to the rest of the body. Cephalopods have blue blood, because they bind oxygen with hemocyanin. Cephalopods have relatively large brains and complex eyes. Cephalopods can change the color of their skin at will, and very quickly. They do this by nerve controlled chromatophores (pigment sacks in the skin), iridiphores (reflect light to appear iridescent), and leucophores (scatter ambient light). Cephalopods also have the ability to squirt “ink” into the water to confuse, or hide from, predators. Cephalopods in the Octopodidae Family are in the order Octopoda. Octopods have eight arms. Their suckers lack muscular stalks and chitinous rings. Their heads attach to their mantle dorsally. They may, or may not, retain a small internal shell, or be equipped with fins. Species in the Octopodidae Family lack filaments (cirri) around their suckers and are in the suborder Incerrata. Two superfamilies, Argonautoidea and Octopodoidea, within the suborder Incerrata separate octopuses from arogonauts. The Octopodidae Family is one of six families in the superfamily Octopoidodea. The Octopodidae Family is fairly large and consists of twenty-three genera and one hundred fifty-four species. The name Octopodidae comes from the Greek words meaning “eight feet” and refers to the eight arms.

Morphology: Benthic Octopuses have muscular arms that are much longer than the body. The suckers lie in one or two rows. The body may be muscular or gelatinous. Their mantle web is usually less than half as long as the arms. They may lack an internal shell, or it may be modified into a pair of stylets that help to support the head. In male Benthic Octopuses, one (right or left) of the third arms is modified to carry sperm in an open groove on the ventral edge. This arm is known as a hectocotylus, and in this family, is not detachable. Octopuses in the Octopodidae Family have excellent eye sight. They may see a broad spectrum of visible light, polarized light, or infrared light, or be color blind. They can not only change the color of their skin, but also its texture, and their body size. Benthic Octopuses range in size from around 7.0 cm (2.8 inches) to 4.8 m (16 feet) in arm-span. Some sources push this maximum to 6 m (20 feet).

Habitat and Distribution: Benthic Octopuses are generally found in rocky habitats, but may range to soft substrates. They live in the intertidal zone, and to depths exceeding 5,000 m (16,400 feet). While octopuses spend most of their time sedentary or crawling slowly along the bottom, they are also capable of rapid movement. By rapidly forcing water out of their siphons, they can “jet-propel” themselves through the water. Octopuses are very intelligent. They use their arms to use tools, build fortresses, tend gardens, and even arm themselves with stinging cells from jellyfish. They are found worldwide, in tropical to polar seas.  Fourteen species from the Octopodidae Family are found Mexican waters.

Reproduction: Benthic Octopuses are gonochoric (male or female for life). They reproduce sexually, with internal fertilization. During mating the male inserts his hectocotylus under the mantle of the female, delivering packets of sperm (spermatophores). They only reproduce once in their life, and die soon after. Many species have a complex mating ritual to ensure getting the best partner. Female octopuses may lay up to 700,000 eggs at one time. The eggs hatch into planktonic larvae.

Ecosystem Interactions: Benthic Octopuses feed primarily on bivalves, crustaceans, and gastropods. Despite their excellent eyesight, amazing camouflage, high intellect, mimicry, a sharp beak and jet propulsion, Benthic Octopuses still have predators. Sea birds, fish, marine mammals, sea turtles, and other octopuses are their more common predators.  Some mimic other animals in order to escape predators. Octopuses also have a sharp beak that can deliver a venom that paralyzes its prey. Only the venom of the Blue-ringed Octopus, Hapalochlaena sp., of Australia, is considered a threat to humans.