This work describes the morphological changes during embryonic development and pre-hatching organ development of Octopus hubbsorum , a species with a paralarval phase in its life cycle. The morphogenesis of O. hubbsorum begins simultaneously with the first reversion, a typical characteristic of octopuses, along with the development of the embryonic shape and structure. However, this species hatches with only three well-developed suckers. Organogenesis starts after the first embryonic reversion, with the development of the eyes, optic lobes, digestive gland, arms, and mantle. The branchial and central hearts show optimal development before the second reversion. The ink sac develops in the late stages (after the second reversion), while the stomach and crop are evident only after hatching and continue to develop until the first feeding. Newly hatched organisms show a complete development of the nervous, respiratory, circulatory, and integumentary systems. During the paralarval phase, O. hubbsorum undergoes major morphological and physiological changes until it reaches the subadult phase and develops the reproductive organs. This study highlights important organogenic differences compared to species with planktonic and benthic hatchlings. Further studies are needed in species with different life strategies to expand our knowledge of the developmental biology of cephalopods.

Humans everywhere have always been fascinated by octopuses, squid, and cuttlefish, known biologically as cephalopods. They evolved hundreds of millions of years ago and are related to molluscs such as mussels and snails. They can grow to an enormous size with eyes as big as footballs, but they still live for only a couple of years. They mate once in their lifetime and die shortly after. They have blue blood and three hearts and they can shoot out jet-black ink. They have a brain and have behaviours that could be interpreted as signs of intelligence, even though more than half of their brain is distributed in their arms. They are colour blind, but they can change the colour of their skin in a flash. They are masters of disguise and are able to alter the texture of their skin and the patterns displayed on it at lighting speed. They can also ‘taste’ using the suckers on their arms. They can move extremely fast thanks to a jet-propulsion system built into their body cavity. Although they are soft-bodied and look vulnerable, cephalopods are formidable predators. Octopuses have arms that are so strong that they can exert a force equal to hundreds of times their own body weight. Squid and cuttlefish can shoot out a tentacle to capture prey at the speed of a javelin thrown by an expert athlete. Cephalopods are, however, so much more than just fascinating creatures with strange physical characteristics. They are a nutritious, delicious protein source that has found a place for thousan

can change color so no one can see it. Octopuses have three hearts and a big brain. Octopuses eat other … stethoscopes- one for each heart! Octopuses need three hearts to pump their blue blood all around their body … in this book grows to be about 3 feet long. Octopuses have eight arms. If an octopus loses an arm it can

Octopus Eyes Page 19 Sea Chameleon Page 20 Three Hearts Page 23 Big Brain Page 24 Home Alone Page … and those with fins. Only about 30 octopuses have fins, so most are in the first group … eopepods into the octopus’s mouth. 20 Three Hearts Most animals make do with one heart,