Octopus bimaculoides holotype

Discussion in 'Physiology and Biology' started by Tintenfisch, Jul 19, 2009.

  1. Tintenfisch

    Tintenfisch Architeuthis Staff Member Moderator

    Joined:
    Nov 19, 2002
    Messages:
    2,083
    Likes Received:
    171
    Hi guys,

    One of the type specimens I came across while visiting the Smithsonian was the holotype of Octopus bimaculoides. Although not as lively as many of the other pics we get here (though the last shot captured a stealthy escape-from-the-jar attempt), I thought some of you keepers (and others) might be interested in seeing these. :smile:
     

    Attached Files:

  2. DWhatley

    DWhatley Cthulhu Staff Member Moderator

    Joined:
    Sep 4, 2006
    Messages:
    19,077
    Likes Received:
    1,123
    Location:
    Gainesville, GA USA
    Kat,
    What would make the suckers become square? I have not seen this using formalin followed by alcohol and it is quite pronounced in your terrific photos. I just notice the 1949 dating so perhaps it is the aging in alcohol?
     
  3. Tintenfisch

    Tintenfisch Architeuthis Staff Member Moderator

    Joined:
    Nov 19, 2002
    Messages:
    2,083
    Likes Received:
    171
    Maybe something to do with being live-fixed - I guess the suckers might squinch up (like the eyes)? If so, that would explain why you don't see this effect on your octos, since I doubt you fix them live... :cry:
     
  4. DWhatley

    DWhatley Cthulhu Staff Member Moderator

    Joined:
    Sep 4, 2006
    Messages:
    19,077
    Likes Received:
    1,123
    Location:
    Gainesville, GA USA
    There are definite advantages to being a layperson :hmm:
     
  5. Steve O'Shea

    Steve O'Shea Colossal Squid Supporter

    Joined:
    Nov 19, 2002
    Messages:
    4,668
    Likes Received:
    17

    You hit the nail on the head there Kat! Fixation artefact. Nice to see the holotype.
     
  6. Cryp_Sis

    Cryp_Sis O. bimaculoides Supporter

    Joined:
    Feb 11, 2008
    Messages:
    63
    Likes Received:
    0
    Great pictures Kat! They got me thinking though. As we have talked about, DNA analysis currently isn’t very helpful in identifying type, and my impression is that the body patterns, colour, texture and posture exhibited, can be useful in distinguishing specimens of a similar size and unknown age. I am guessing (based on some of the other holotype specimens you have come across!) that there is not a lot of additional documentation about the colour patterns and posture seen in the live specimen prior to fixation… Although perhaps this is not really an issue when collecting type specimens, as one always has the geographical location to help distinguish between species? Just thinking out loud, really. In any event, I guess that wouldn’t do you much good for your Arctic projects, since many of the specimens come in mortally challenged.
    Thanks for posting. It’s good to see the original.
    Cheers,
    Lene.
     

Share This Page