FAQ
A contribution of The Cephalopod Page
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James, Hello, I recently became interested in keeping octopuses as pets and have found your 'Cephalopod Page' to be the only good source of information on octopuses. Your page serves as the starting point for all my searches for info on octopuses (and sometimes others as well). Keep up the good work!! The reason I am writing you is to ask for your help. I acquired an octopus a couple days ago that matches the description of a small 'Common' or a 'Dwarf' except for a couple of characteristics I have not seen documented anywhere. I am hoping you can help me identify the species and locate information about this species. The characteristics in question are as follows: 1. Dark circular area on either side of body just below the eye's, which contains a blue ring similar to that of the 'Blue Ringed' octopus. I assume these to be fake (dummy) eyes. 2. The suckers are orange (towards the tip). The only time they vary from this coloration is when it turns completely white. Other than these two things he fairly normal coloration(s) for either of the above mentioned species though it does display more vividly than other octopuses I have seen. Any help or suggestions you can offer would be greatly appreciated! I am working on getting a good photo of it, but taking a good picture of something in an aquarium is difficult (as you probably know). When I manage to get a decent photo I will forward a copy to you for use on the 'Cephalopod Page' if you like |
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| Identifying octopuses, especially ones bought at a pet store which could be from anywhere in the world, is very difficult. There are over 100 species in the genus Octopus alone. And there are other genera such as Bathypolypus, Eledone and Hapaloclaena. Octopuses in the genus Octopus, plus many of the others, all have two rows of suckers, can change color and body shape, and well, basically look like octopuses - even experts have problems identifying them by sight. Add to this the fact that many species are undescribed - even some common species found in shallow water. For instance, there is one or more species of undescribed but very common octopus living in shallow water off of Hawaii. Who knows how many are waiting to be found in the Indo-Pacific. I'm not an expert at octopus identification (I study life history and behavior), but can identify most octopuses that are from the Caribbean by sight but not usually by description (unless it is a scientific description). Yours is not a common Caribbean species. There are two species from the west coast that have eye spots - Octopus bimaculoides and O. bimaculatus - you MIGHT have one of those. Scientists can (usually) identify cephalopods - characteristics such as behavior, mantle length, arm length, weight, egg size, number of suckers per arm, radula pattern, beak morphology, funnel organ shape, number of gill branches, etc are used. A few of these characteristics can be observed simply by viewing the animal but accurate identification based on visual inspection often requires prior experience with that particular species. Some of these characteristics can be observed with an anesthetized specimen but many require dissection to observe. Scientists are also careful to keep records of where, when and how the animal was collected and that information narrows the search considerably. This is why it isn't worth the cost, especially if the animal is of unknown origin, to id a hobbyists pet ceph. Dr. James Wood |