Discussion in 'Sources for Cephalopods and Food' started by kwilliams10@woh, Jan 27, 2008.
Can anyone help me decide?
I am pretty sure that there are no breeds in cephalopods...
Cuttlefish, octopus, what types???
Octopus- Octopus bimaculoides
Cuttlefish- Sepia bandensis (Sepia pharaonis and Sepia officinalis require larger systems and costs can rise)
Just my opinions.
Do you possibly have any specific questions.
Sorry, was in a rush and just finished typing an email to someone about selling one of my pups....yet types........I had a vulgarus before...lived for about 8months. Looking for a type that would be smaller pygmy or dwarf...or possibly a briareus....and that would live longer...with more activity.
"dwarf" and "live longer" are pretty much not compatible, unfortunately. We've found that bimacs and briareus are the best "happy medium" for the most part, although aculeatus seem to be getting more common and may make the short list. The jury's still out on hummelincki (a.k.a. filosus) as far as I'm concerned, a lot have died very soon after arrival, but that may have been a freak occurrence for one batch... I'm not sure how big or long-lived they are as adults, but they're somewhat smaller so I'd expect them to be similarly short-lived to other dwarfs, but they seem to be more day-active than mercs, for example.
I would not think that hummelincki classifies as a dwarf species, it has shorter arms than most other medium sized octos but the mantle is far larger (wider and longer) and the webbing and legs are much, much thicker than even the largest Mercatoris. However, I have seen Mucktopus refer to the Marginaris as a dwarf species so I may be using incorrect criteria (or there is a difference in a dwarf and a pygmy).
Yeah, it seems pretty arbitrary where people "draw the line"-- it doesn't sound like hummelicki gets as big as bimacs or briareus, but is bigger, and more day-active and outgoing than mercs, joubini, and the other small dwarfs we've seen. I haven't heard of anyone's aculeatus getting as big as bimacs can, but I think they definitely get bigger than most dwarfs and also seem a lot more interactive and day-active. I think I'd heard rubescens described as a dwarf before, but it's certainly bigger than most, and one of the pros (Roy?) corrected me when I referred to it as a dwarf.
Some sizes from reference books for octos we see as pets:
Octopus mercatoris Norman: (not listed) Nesis: synonym for Joubini, 5cm ML max, but 2-3cm ML typical
Octopus digueti Norman: pygmy, 5cm ML, Baja California
Octopus joubini Norman: pygmy, 4cm ML, Gulf of California and Caribbean, says it's confused with a similar large-egg species, maybe mercatoris? Nesis: 5cm ML max 2-3cm ML typical
Octopus hummelincki (a.k.a. filosus) Norman: not pygmy, 7cm ML, Caribbean Nesis: 7cm ML max 3-4cm ML typical
Abdopus aculeatus (a.k.a. Octopus aculeatus) Norman: not pygmy, 6cm ML, Philippines to Australia Nesis: not listed
Octopus rubescens Norman: not pygmy, 10cm ML, Gulf of Alaska to Gulf of California Nesis: 5-10cm ML
Octopus marginatus Norman: not pygmy, 8cm ML, tropical Indian and West Pacific Nesis: not listed
Octopus bimaculatus Norman: not pygmy, 20cm ML, California to Gulf of California Nesis: 10-18cm ML
Octopus bimaculoides Norman: not pygmy, "at least" 12cm ML, "mid-coast" California to Baja Nesis: 7-20cm ML
Octopus briareus not pygmy, 12cm ML, Caribbean and Gulf of Mexico Nesis: 10-12 cm ML
Octopus cyanea Norman: not pygmy, "at least" 16cm ML, tropical Indo-Pacific Hawaii to east Africa Nesis: mentioned, but no length described
Octopus vulgaris Norman: not pygmy, several different species, "at least" 20-25cm ML, all over tropical and temperate (but not Eastern Pacific) Nesis: 20cm (30cm) ML
so it sounds like Norman says 6cm ML or bigger is not "pygmy."
Maybe this data can be a start for a "list of the different types of octo we see in the pet trade"
That list and its format have me wondering about the possible importance of mantle Max amd Mantle typical sizes. Trapper was in the Max category but her young are the smaller, typical size at 10 + months. It appears AM's hummelincki, Tuvalu was of the typical (I don't have a reference on the others of that group) and Octane is in the max range. The differences are substantial and I am wondering if anyone in the biology group has done any kind of study on why there is such a difference and if it plays any part in longevity.
Until I saw the list, I was thinking the smaller sizes of my tank raised Mercs was directly related to the size of their environment, now I don't think that is the case and I think male vs female can be ruled out too.
Also, in the case of hummelincki, the girth of the mantle, web and arms is at least twice that of the Merc and none of the statistics mentions a combination of length and width, which, in the case of any octopus, is an important measuring consideration.
Yeah, both of the books I was looking at specified arm length as well, but I can only transcribe so much without going . In an ideal world, we'd make a list of commonly kept pet octos that includes typical and max for ML and arm span, and water temp, and large-or-small-egg, and where they're found, and relative rarity, and personality, and typical lifespan, and maybe how to ID at young and adult sizes, and what foods they seem to accept,and typical posture, and typical schedule, and how flexible their schedule can be, and links to gallery pictures, and probably other stuff I can't think of...
BUT I must insist that any mention of octo length (head, arm, web, whatever) has to include at least length AND width (thickness would help too) since these no boned creatures can alter these but not change its mass. It is not your lack of transcription nor the lack of other info I am complaining about, the recorded measurements don't help much if they are single dimentional. I think Steve said something to that effect about being able to stretch a dead squid's tentacle to make it any length desired.
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