Sea Life

How Do Octopus Mate?The Story Of The Detachable Octopus Penis

You have heard about the most popular species of tropical and subtropical regions – the Octopus. The recorded data suggested that about 300 species of octopus or even more live under the water. The unique Cephalopod has 3 hearts, 8 arms, and 9 brains but have you ever wondered about the mating behavior of octopus? No! Not a big deal. In this article, we are going to share every detail about the mating rituals of this extraordinary creature.

How Does Octopus Mate?

The reproductive pattern of an octopus is quite different and unique. The male octopus bears an extra-long arm called a hectocotylus also known as the sex arm. The hectocotylus helps the octopus to deliver sperm into the female reproductive organ from a distance to fertilize the eggs. Only one egg is fertilized by the hectocotylus. The mating behavior of octopus lasts from a few minutes to a longer period of 4 hours.

What Is The Structure Of Hectocotylus?

Hectocotylus is a part of the male reproductive system, which comprises 3 parts:

1:  Spermatophore groove

2:  Calamus

3:  Ligula

The spermatophore groove is a cup-shaped curved structure located on the side arm which holds rows of sperm. The spermatophore groove of an octopus is 1 meter long and contains billions of sperms. At the base of the spermatophore groove, a triangular-shaped structure called the calamus is located on one end and the spoon-shaped ligula is on the other end. When a male octopus approaches the female for mating, the 3 organs work simultaneously to transfer the sperms in the female’s mantle.

What Is The Structure Of The Reproductive System Of  A Female Octopus?

The reproductive system of the female octopus is not as complex as that of the male, the reproductive system comprises a single ovary, and two oviducts – each oviduct has an oviducal gland. These oviducts open up into the female’s mantle. When the male deposit sperms in the mantle, the sperm moves toward the ovary to fertilize the eggs.

What Happens When The Octopus Completes The Mating Process?

After the completion of mating, the male octopus dies whereas the females store the sperm to fertilize the eggs. After fertilization, the female lays eggs and protects them from predatory animals and environmental conditions. When the gestation period of 40 days is completed, the eggs hatch, and then the female octopus will lead to her death.

Argonaut Octopus – The Story Of The Detachable Octopus Penis

The Argonaut Octopus is a group of pelagic octopuses which belongs to the genus Argonauta. The specialty of the members of this genus is that the males are only a few centimeters in length whereas the females are 30 times larger in size than the male octopus.

Interestingly, the males have the unique ability to detach the hectocotylus and hand it over to the female for mating. The female octopus in turn fertilizes herself with the sperm present in the spermatophore of the detached arm. Researchers believe that by this unique reproductive method, the female octopus can mate with several detachable arms before fertilization. After fertilization, the female releases larvae in the water, which swim away and develop on their own.


There are more than 300 species of octopus living in the open waters of the world. The octopuses exhibit a unique pattern of reproduction. The male has a reproductive organ called a hectocotylus (sex arm) having a spermatophore groove that contains sperm. When the male octopus finds its mate, it lodges the sperm in the female’s mantle for fertilization of eggs. However, Argonaut Octopus can detach the hectocotylus and hand it over to a female to fertilize herself on its own. Sadly, both male and female octopuses die after mating.

About the author


I am a Scholar and a dedicated content writer. I am on a mission to stamp out the importance of one of the ocean's most fascinating and remarkable creatures, the sharks, and to let people know about their role in keeping the ecosystem in equilibrium.