Trying to clear up some confusion: What exactly are cephalopods?

[kmk2307]

Cephalopods are highly evolved molluscs characterized by bilateral body symmetry, a prominent head, and a modification of the molluscan foot into the form of arms and/or tentacles that surround the mouth. They have well developed brains and eyes, a hard and chitinous beak, and in many cases complex defense mechanisms and/or ways to subdue prey such as “ink,� potent venoms, and color changing chromatophore cells. Due to the similarity of the name, they are sometimes confused with amphipods or copepods which are small shrimp-like crustaceans. The class cephalopoda is supertended by the phylum Mollusca and it contains two subclasses, Coleoidea which contains the octopus, squid, and cuttlefish and Nautiloidea which only contains the few species of nautilus.

There are around 700 species of cephalopods worldwide in all undersea habitats, and surprisingly few inhabiting the coral reefs. Most cephalopods have a short life span with fast growth rates and only a life expectancy of one to three years. Cephalopods are the most active of the molluscs and some squids rival fishes in their swimming speed. Cephalopods are an ancient group that appeared some time in the late Cambrian several million years before the first primitive fish began swimming in the ocean. By the time the Coleoidea separated from the Nautiloidea, vascular plants and vertebrates had still not reached land. Some of the most spectacular cephalopods are the giant squid such as Architeuthis dux, whose body length (not including arms and tentacles) can grow in excess of 18 feet. They are the largest known invertebrates. Based on analysis of stomach content, these squid eat fish and other small squid.

In the home aquarium only small species are appropriate and these amazing creatures demand a great degree of planning and care. Octopus bimaculoides is one species of octopus commonly kept in captivity. This octopus can be fed meaty foods like shrimp, crab, and bivalve meat. They should be kept in aquariums with tight fitting lids that cannot be easily propped up from the inside and the rockwork in the aquarium should be extremely stable so that it cannot topple down onto the octopus that may enjoy digging and rearranging his habitat. It is also important to make sure powerhead strainers and other intake covers cannot be pulled off by these inquisitive cephalopods as they can be sucked in and irreparably injured or killed.


Southern Calamari Squid Sepioteuthis australis


Mourning Cuttlefish Sepia plangon


Giant Cuttlefish Sepia apama


Chambered Nautilus Nautilus pompilius


Blue-lined Octopus Hapalochlaena fasciata


Common Sydney Octopus Octopus tetricus
Courtesy of ATJ

[OctoMonkey]

what was that for?

[kmk2307]

A lot of people have been comming in the cephalopod forum and posting about amphipods and copepods and other organisms that have a name ending in -pod. A lot of casual hobbists don't know a lot of the scientific names for the organisms we keep. When they see pepople refer to pods as small "bugs" in tanks and then they see the somethingapod forum they relate the two and post here about their amphipod. I talked to some people in TRC and they thought it would be good to try to assemble a little writeup on cephalopods. All comments and additional information you would have included if you were gonna write something like this are appreciated.

Thanks,
Kevin

[OctoMonkey]

That's a very good idea... can you not make it sticky so it sits at the top of the forum?

How about an amphipod/copepod forum?

[kmk2307]

I can't make it sticky but I think someone out there is going to.

How about an arthropod forum? I don't think an echinoderm forum would hurt either.

Kevin

[JRHazer]

You seem like the guy to ask.... Can people keep Nautiluses in species tanks?

It seems like something cool to try... just wondering if it can or has been done.

[traveller7]

It has been done, normally with very poor results.

Hit the search button at the top of the page, there is lots of good advice out there.

Cheers.

[Dragonscales]

An interesting tidbit about the nautilus is that they can survive extreme changes in water pressure due to their unique chambered design. This makes them one of the only deepsea lifeforms that is able to be pulled from the depths at high speed without being mutilated via stress to the body.

[Brad524]

where could i find the two cuddlefish in the top pictures

[kmk2307]

Brad,

Very few cuttlefish are available in the hobby. www.liveaquaria.com may have one species for sale.

Kevin

[LisaD]

Kevin,

Great write-up!

Off-topic, I know, but what is that in your avatar? It looks like a water bear (tardigrade) to me. Just curious...

Lisa

[kmk2307]

High five, Lisa! It is a tardigrade! I think I need to find another spiffy invertebrate to replace that with. It's been the same for about a year now.

Thanks,
Kevin

[Key Of David]

FYI the folks at GARF have been keeping rare nautilus with success. You may want to give their website a looksee.

[Kelmen]

Originally posted by kmk2307
...somethingapod...their amphipod...

LOL

Actually... this is my 1st time into this subforum.... and I really thought this is for the something-a-pod ! LOL

I would highly suggest put some additional info and the subforum name, maybe like Cephalopods (squid like invertebrate)
Or something in common more better to replace the red one.

Else, many guys like me will definately hit into these subforum. I can tell you many are interested in the PODS.
Not to mention some don't bother to read sticky thread.
Save their (my) time from entering, as well as some igonarants.

[titleist]

How do these creatures do in a reef aquarium? Special needs, tank size, bennifits, etc........

[LisaD]

Define reef. They would eat crabs, shrimp and many or all of the fish. They knock down and mover rocks (especially octopus) so corals could be toast too...

[LisaD]

troll

[Jesse-KT]

What is the largest kind of octo for sale?

[Ranzan]

if your reallllyyy ambitous and you can supply a 20,000 gal tank you could get your hands on a giant pacific octo second largest species of octo in the world but its very unlikely for a hobbiest to do something like that. Plus im sure the cost of one of these would be well in the 5,000+ range. these are also very large and can weigh upto 50kg on average