{"id":3591,"date":"2026-10-02T04:24:53","date_gmt":"2026-10-02T03:24:53","guid":{"rendered":"https:\/\/www.farmersforum.ie\/trends\/the-lions-mane-jellyfish-a-giant-with-1200-tentacles-weighing-over-a-ton\/"},"modified":"2026-10-02T04:24:55","modified_gmt":"2026-10-02T03:24:55","slug":"the-lions-mane-jellyfish-a-giant-with-1200-tentacles-weighing-over-a-ton","status":"publish","type":"post","link":"https:\/\/www.farmersforum.ie\/trends\/the-lions-mane-jellyfish-a-giant-with-1200-tentacles-weighing-over-a-ton\/","title":{"rendered":"The Lion&#8217;s Mane Jellyfish: A Giant with 1,200 Tentacles Weighing Over a Ton"},"content":{"rendered":"<figure class=\"wp-block-image aligncenter size-large\"><\/figure>\n<p><strong>If you were asked to name a giant of the oceans, the blue whale would probably be the first creature that comes to mind. Today we turn our attention to a very different but equally impressive being: the lion&#8217;s mane jellyfish.<\/strong><\/p>\n<p><span id=\"more-990836\"><\/span><\/p>\n<h2 class=\"wp-block-heading\"><strong><em>Cyanea capillata<\/em><\/strong><\/h2>\n<p>Primarily inhabiting the cold waters of the Arctic Circle, as well as the North Pacific and North Atlantic, <em>Cyanea capillata<\/em> is regarded by the Guinness World Records as the largest jellyfish in the world, with specimens weighing over a ton and measuring more than two meters in diameter.<\/p>\n<section class=\"incontent-related\"><span class=\"incontent-related__title\">Read also<\/span> <span class=\"incontent-related__desc\">In the Pyrenees, this small mammal has become almost invisible, but the water still reveals its presence<\/span><\/section>\n<p>Its \u201clion&#8217;s mane\u201d consists of roughly a thousand tentacles that can extend beyond thirty meters. Generating large quantities of neurotoxins, they enable it to capture a variety of prey, including small fish, zooplankton, and ctenophores.<\/p>\n<p>If the sting of <em>C. capillata<\/em> typically causes blisters, irritation and muscle cramps, in the most severe cases it can affect the functioning of the respiratory and cardiac systems. Even specimens that have stranded for a long time remain venomous.<\/p>\n<p>This fascinating creature lies at the heart of one of Sir Arthur Conan Doyle&#8217;s Sherlock Holmes adventures from 1926: <em>The Lion&#8217;s Mane<\/em>, in which the giant jellyfish kills a man and his dog and grievously wounds another.<\/p>\n<section class=\"incontent-related\"><span class=\"incontent-related__title\">Read also<\/span> <span class=\"incontent-related__desc\">These raccoons learn mutually to make toys with paper and sand<\/span><\/section>\n<figure class=\"wp-block-image aligncenter size-full is-resized\"><img decoding=\"async\" width=\"730\" height=\"487\" src=\"https:\/\/www.farmersforum.ie\/trends\/wp-content\/uploads\/2026\/10\/1790911493_579_The-Lions-Mane-Jellyfish-A-Giant-with-1200-Tentacles-Weighing.jpg\" alt=\"M\u00e9duse \u00e0 crini\u00e8re de lion\" class=\"wp-image-990843\" style=\"width:730px;height:auto\"  ><\/figure>\n<h2 class=\"wp-block-heading\"><strong>The Largest Jellyfish in the World?<\/strong><\/h2>\n<p>Captured off the coast of North America in 1870, the largest known specimen of <em>C. capillata<\/em> is thought to have measured 2.3 meters in diameter, with tentacles extending over 37 meters. This claim has been debated by many scientists, who today regard Nomura&#8217;s jellyfish as the largest known.<\/p>\n<p>Among its relatives, Nomopilema nomurai (Nomura&#8217;s jellyfish) can also exceed two meters in diameter and weigh more than 200 kilograms, primarily in the Sea of Japan. Its remarkably rapid growth today makes it a nuisance for local fishermen.<\/p>\n<p>At the opposite end of the spectrum are the various \u201cIrukandji\u201d jellyfish species. Not exceeding 5 centimeters in diameter and possessing only four tentacles, they are among the most venomous creatures in the world, with stings potentially deadly to humans.<\/p>\n<section class=\"incontent-related\"><span class=\"incontent-related__title\">Read also<\/span> <span class=\"incontent-related__desc\">The highly unusual anatomy of a new large herbivorous dinosaur is shaking up paleontologists&#8217; benchmarks in China<\/span><\/section>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":3592,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[536,1447,90,2454,2455,2457,2456],"class_list":["post-3591","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news","tag-giant","tag-jellyfish","tag-lions","tag-mane","tag-tentacles","tag-ton","tag-weighing","generate-columns","tablet-grid-50","mobile-grid-100","grid-parent","grid-50"],"_links":{"self":[{"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/posts\/3591","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/comments?post=3591"}],"version-history":[{"count":1,"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/posts\/3591\/revisions"}],"predecessor-version":[{"id":3593,"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/posts\/3591\/revisions\/3593"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/media\/3592"}],"wp:attachment":[{"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/media?parent=3591"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/categories?post=3591"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.farmersforum.ie\/trends\/wp-json\/wp\/v2\/tags?post=3591"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}