Invertebrate Project

Grimpoteuthis

Dumbo Octopus

 

Phylum: Mollusca

Class: Cephalopoda

• Protosome 
• Bilateral symmetry
• 3 germ layers

Essential Functions

Body Structure:

• Ear-like fins on top of the head
• 8 tentacles connected by webbing
• Tentacles have 1 row of suckers and 2 rows of cirri (fleshy spikes) 
• Dumbo octopus can grow to 20-30cm long

Digestion (Feeding):

• Grimpoteuthis eat crustaceans, worms, bivalves and small fish
• They hover over the bottom and use their tentacles and cirri to get food into their mouth
• Their radula is reduced or totally gone
• Therefore, they swallow prey whole!

 

Circulatory:

• All octopi have 1 main heart and 2 smaller ones near their gills
• The smaller ones pump blood to the gills and pump blood with oxygen to the main heart
• Octopus blood has hemocyanin which makes it blue instead of hemoglobin that would turn it red

Respiration:

• The Dumbo octopous respire the same way as other octopi, they use gills to get oxygen from the water
• As the oxygen passes over the feathery gills it gets passed into the blood and transported trhough the body

 

Excretion:

• The Dumbo Octopus has an anus to release solid waste
• They also have nephridia that collect fluids, concentrate them and put them with the other waste going out the anus
  

Movement:

• They hover over the sea floor
• To move they expand and contract their webbed arms
• They are also able to shoot water through their funnel 
• They can also flap their fins on their head

Reproduction:

• Females lay eggs all year round, have no specific breeding season
• They lay their eggs under rocks and leave them to fend for themselves
• Males have a large segment on their arm to transfer sperm packet (spermatophore) into female mantle cavity
• Packet ruptures when it enters and fertilizes the eggs

Another organism in the phylum Mollusca is the squid.  Squids are similar to octopus because they are both in the class Cephalopoda.  They both have arms with suckers on them however, squids also have two long tentacles that they use to capture their prey.  They also have a closed circulatory system filled with hemocyanin similar to octopi.  Both cephalopods squirt out ink when they feel endangered.  Squids and octopus can both move by jet propulsion but the dumbo octopus has fins on its head that it uses to swim as well. 

Interesting Facts:

• Dumbo Octopus can be found from 400m - 4800m deep in the ocean
• The largest one ever found was about 6 feet long and weighed 13 lbs.
• There are 37 known species of the Dumbo Octopus

I love this Invertebrate because of it's interesting appearence and it's unusual resemblence to the Disney character Dumbo.