新發現的巨型章魚
最近，人們新發現了一種巨型章魚。因為這種巨型太平洋物種看起來與太平洋巨型章魚（簡稱GPO）十分相似，所以我們一直以為是同一種。
它還沒有正式的名字。因為它的外觀與GPO非常相似，現在人們稱它為「帶褶皺的太平洋巨型章魚」。現在還沒有足夠的證據由這些細微差別證明它們是兩個不同的物種。
其實，2012年在阿拉斯加威廉王子灣水域，人們取得了它們的DNA，證實它們是兩種基因截然不同的物種，但是當時只有章魚的觸鬚，也沒有拍照，所以沒有留下視覺證據。
來自阿拉斯加太平洋大學（Alaska Pacific University）的海洋生物學家大衛·謝爾（David Scheel）和學生內特·霍倫貝克（Nate Hollenbeck）介入研究，嘗試發現不同的物種。他們收集了21種活體章魚，它們是阿拉斯加漁獵部進行蝦類調查時意外捕獲的。
21種活體章魚中，其中7種章魚的外套膜上有褶邊，頭上有多個白色斑點，而GPO只有一個白色斑點。這7種章魚，每一種的眼睛上都有一條長而細的主乳突，這種特徵在太平洋巨型章魚中很少見。這些新發現的章魚都至少擁有其中一種特徵，而平常的GPO都沒有這些特徵。
他們抽取了章魚樣本，然後到實驗室檢測它們的DNA。驚人的是，這七種基因各不相同。另一個有趣的是，傳統的DNA測試需要切取皮膚組織作為樣本，研究團隊採集了皮膚組織，但同時也使用了藥棉取代皮膚組織，減少對章魚的侵害。在七項測試中，運用兩種方法檢測出的DNA結果都一樣，表明後面這種測試方法是可行的。
現在有了視覺識別，現場識別並確定動物種類和種群數量將更加容易。雖然這種章魚還沒有完整的描述和正式命名，但這項研究已於11月在美國的《American Malacological Bulletin》雜誌上發表。
原文：
CthulhuAmongUs: A new giant octopus discovered
A new species of giant octopus was recently discovered right underneath out noses. It seems there are actually two giant pacific species we』ve been lumping under one name — the Giant Pacific Octopus (GPO).
Although it doesn』t have an official name, its being dubbed the 「frilled giant Pacific octopus」 for now since its very similar in appearance to the GPO,Enteroctopus dofleini, but there hasn』t been enough evidence to consider the slight nuances as being two separate species.
There was, however, DNA evidence of two genetically distinct species in the waters of Prince William Sound in Alaska from at least 2012. But at the time, only snips of the octopuses tentacles were taken without photographs, so there was no visual evidence.
This is when David Scheel, a marine biologist from Alaska Pacific University, and Nate Hollenbeck, then a student, stepped in to see if they could find the different species. They collected 21 live octopuses snared as bycatch in shrimp pots as part of the Alaska Department of Fish & Game shrimp surveys.
Of the 21, a third of them had frills all over their mantles and white spots on the front of their heads compared to the one white dot on the GPO. They all also had one long, thin, major papillae over each eye, a trait that occurs only rarely in the giant Pacific octopus. All of the new octopuses had at least one of these traits and none of the regular GPOs did.
They took samples and later tested the DNA at the labs and guess what? All seven were genetically different. Another interesting side note. Traditional DNA testing involves snipping skin tissue for a sample and the team did this, but they also used a cotton swap of the skin — a much less invasive practice. In all seven tests, the DNA results were the same demonstrating this is a viable method for testing.
Now that there is visual identification, it will be easier to identify in the field and determine the range and population numbers. Although the octopus is yet to be fully described and named, the research has been published in November in theAmerican Malacological Bulletin
[via Earther]
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