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

kmk2307 · 12/30/2003, 04:06 PM

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 Ã¢â‚¬Å“ink,Ã¢â‚¬Â 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 · 12/31/2003, 04:28 AM

what was that for?

kmk2307 · 12/31/2003, 01:24 PM

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 · 01/01/2004, 06:06 AM

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 · 01/01/2004, 01:07 PM

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 · 08/04/2004, 11:21 AM

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 · 08/06/2004, 12:06 PM

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 · 09/19/2004, 04:45 PM

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 · 12/12/2004, 07:12 PM

where could i find the two cuddlefish in the top pictures

kmk2307 · 12/12/2004, 07:20 PM

Brad,

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

Kevin

LisaD · 12/24/2004, 12:17 AM

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 · 12/26/2004, 01:49 PM

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 · 02/01/2005, 07:39 PM

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

Kelmen · 06/10/2005, 04:28 AM

Quote:

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 · 07/23/2005, 11:01 PM

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

LisaD · 07/24/2005, 07:55 AM

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 · 10/07/2006, 06:04 PM

troll

Jesse-KT · 02/23/2007, 09:42 AM

What is the largest kind of octo for sale?

Ranzan · 10/27/2007, 12:33 AM

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

Paul_PSU · 02/16/2008, 06:33 AM

If you were to keep a tank with just an octo in it, what is the smallest size(tank) you would recommend and also what kind of lighting?

Thanks!

Animal Mother · 02/17/2008, 10:39 AM

50-75 gallons is ideal for most common species.

Octavarium · 03/22/2008, 11:40 AM

Cephs are the coolest guys in the ocean

gholland · 03/22/2008, 01:09 PM

Quote:

Originally posted by Octavarium
Cephs are the coolest guys in the ocean

Or an aquarium! Although they share that #1 spot with stomatopods in my book.

Seems like it wouldn't be too hard to add (octopus/squid/cuttlefish) to the forum title though.

Thales · 04/30/2008, 07:52 AM

Quote:

Originally posted by Key Of David
FYI the folks at GARF have been keeping rare nautilus with success. You may want to give their website a looksee.

This comes up from time to time, but I am unable to find any actual info on it, except references to something that happened in 1978 IIRC. If you could provide a link, I would love to read more.

Thanks

RR

jdieck · 04/30/2008, 08:17 AM

If the word cephalopod means something like head at the center or radiated from the head, will a starfish be a cephalopod

12/31/2003, 04:28 AM	#2
OctoMonkey Registered Member Join Date: Dec 2001 Location: Larkhall, Scotland Posts: 694	what was that for? __________________ ...and the Earth died screaming, while I lay dreaming.

01/01/2004, 06:06 AM	#4
OctoMonkey Registered Member Join Date: Dec 2001 Location: Larkhall, Scotland Posts: 694	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? __________________ ...and the Earth died screaming, while I lay dreaming.

08/06/2004, 12:06 PM	#7
traveller7 Time to get back in? Join Date: Jul 2002 Location: Northern Virginia Posts: 9,441	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. __________________ Scott Current Tank Info: Glass 2.5's

12/12/2004, 07:12 PM	#9
Brad524 Registered Member Join Date: Dec 2004 Location: near Wisconsin Dells Posts: 326	where could i find the two cuddlefish in the top pictures __________________ After tons and tons and tons of research I still know nothing Together Everyone Acheives More Current Tank Info: Planning monster tank

12/24/2004, 12:17 AM	#11
LisaD That's not a salmon Join Date: Mar 2003 Location: central North Carolina Posts: 6,986	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 __________________ Keeping saltwater tanks since the late '70s Current Tank Info: tankless at the moment

12/30/2003, 04:06 PM	#1
kmk2307 Registered Member Join Date: Jun 2001 Location: Tuscaloosa, AL Posts: 5,110	Trying to clear up some confusion: What exactly are cephalopods? 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 Ã¢â‚¬Å“ink,Ã¢â‚¬Â 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

12/31/2003, 01:24 PM	#3
kmk2307 Registered Member Join Date: Jun 2001 Location: Tuscaloosa, AL Posts: 5,110	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

01/01/2004, 01:07 PM	#5
kmk2307 Registered Member Join Date: Jun 2001 Location: Tuscaloosa, AL Posts: 5,110	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

08/04/2004, 11:21 AM	#6
JRHazer Registered Member Join Date: Nov 2003 Location: Geneva,IL Posts: 38	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.

09/19/2004, 04:45 PM	#8
Dragonscales Registered Member Join Date: Sep 2004 Location: Ballarat, Victoria, Australia Posts: 7	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.

12/12/2004, 07:20 PM	#10
kmk2307 Registered Member Join Date: Jun 2001 Location: Tuscaloosa, AL Posts: 5,110	Brad, Very few cuttlefish are available in the hobby. www.liveaquaria.com may have one species for sale. Kevin

12/26/2004, 01:49 PM	#12
kmk2307 Registered Member Join Date: Jun 2001 Location: Tuscaloosa, AL Posts: 5,110	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

02/01/2005, 07:39 PM	#13
Key Of David Registered Member Join Date: Dec 2004 Location: Lexington, SC Posts: 89	FYI the folks at GARF have been keeping rare nautilus with success. You may want to give their website a looksee. __________________ Love Your Enemies. Current Tank Info: 55 Gallon FOWLR, 2 Ocellaris Clownfish, 1 Bicolor Blenny, 1 Peppermint Shrimp, 2 Scarlet Hermits, Various LR Lifeforms, More on the way....slowly

07/23/2005, 11:01 PM	#15
titleist Registered Member Join Date: Jul 2005 Location: Nampa, Idaho Posts: 54	How do these creatures do in a reef aquarium? Special needs, tank size, bennifits, etc........

07/24/2005, 07:55 AM	#16
LisaD That's not a salmon Join Date: Mar 2003 Location: central North Carolina Posts: 6,986	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... __________________ Keeping saltwater tanks since the late '70s Current Tank Info: tankless at the moment

10/07/2006, 06:04 PM	#17
LisaD That's not a salmon Join Date: Mar 2003 Location: central North Carolina Posts: 6,986	troll __________________ Keeping saltwater tanks since the late '70s Current Tank Info: tankless at the moment

02/23/2007, 09:42 AM	#18
Jesse-KT Registered Member Join Date: Feb 2007 Location: New Jersey Posts: 88	What is the largest kind of octo for sale?

10/27/2007, 12:33 AM	#19
Ranzan Registered Member Join Date: Mar 2007 Location: Fort Cambell Kentucky Posts: 444	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 Last edited by Ranzan; 10/27/2007 at 12:39 AM.

02/16/2008, 06:33 AM	#20
Paul_PSU Moved On Join Date: Jan 2008 Location: Pittsburgh, PA. Posts: 1,512	If you were to keep a tank with just an octo in it, what is the smallest size(tank) you would recommend and also what kind of lighting? Thanks!

02/17/2008, 10:39 AM	#21
Animal Mother Registered Member Join Date: Dec 2005 Location: Texas Posts: 452	50-75 gallons is ideal for most common species. __________________ "You might not believe it but under fire Animal Mother is one of the finest human beings in the world. All he needs is someone to throw hand grenades at him for the rest of his life." - Full Metal Jacket Current Tank Info: 60 gallon cube, w/ 30 gallon sump, octopus-proof lid. Dry for now.

03/22/2008, 11:40 AM	#22
Octavarium Registered Member Join Date: Mar 2008 Location: East Haven, CT Posts: 88	Cephs are the coolest guys in the ocean

04/30/2008, 08:17 AM	#25
jdieck Registered Member Join Date: Dec 2002 Location: Maumee, OH Posts: 15,673	If the word cephalopod means something like head at the center or radiated from the head, will a starfish be a cephalopod __________________ Did I write what I wrote? What the heck am I talking about! Well..... Nevermind. Current Tank Info: 225 gal reef, DSB, 40 g sump w/ LRT100 return, 37 g pre-sump, 3 MH 250 W 15K, 4 96 W PC dual actinic,ETS 1500 Skim.w/LRT70, 20 lb Ca R., 40 W UV, 1/3 HP chiller, two 350 W Htrs, Neptune II Cont., 330 P LR/ 330 P LS. 55 gal Refugium