{"id":754207,"date":"2026-06-22T19:28:10","date_gmt":"2026-06-22T19:28:10","guid":{"rendered":"https:\/\/www.newsbeep.com\/ca\/754207\/"},"modified":"2026-06-22T19:28:10","modified_gmt":"2026-06-22T19:28:10","slug":"newly-described-australian-ballista-spider-builds-a-spring-loaded-snare-to-catch-a-single-ant-species","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/ca\/754207\/","title":{"rendered":"Newly described Australian ballista spider builds a spring-loaded snare to catch a single ant species"},"content":{"rendered":"

<\/p>\n

\"Ballista<\/p>\n

<\/a><\/p>\n

image:\u00a0<\/p>\n

A ballista spider (Propostira sp.) waits for a green tree ant (Oecophylla\u00a0smaragdina) to bite the cone of its web and thus spring the snare<\/p>\n

view more\u00a0<\/a><\/p>\n

Credit: Professor Ajay Narendra et al<\/p>\n

An international team of researchers have discovered a remarkable new spider species in the rainforest of north Queensland that spins an ingenious and powerful spring-actuated snare to catch a single species of ant \u2013 one ant at a time \u2013 in what they describe as \u201cthe ultimate specialisation\u201d.\u00a0<\/p>\n

Nicknamed the ballista spider after the ancient Roman weapon that used a spring to launch a bolt\u202for stone, the small nocturnal spider has\u00a0apparently evolved\u00a0a\u00a0unique web mechanism to trap only the highly territorial and aggressive green tree ant\u00a0Oecophylla\u00a0smaragdina.\u00a0<\/p>\n

A detailed description of the spider\u2019s predatory strategy and mechanics is published in the latest issue of the journal\u00a0Current Biology<\/a>.\u00a0The spider \u2013 which is yet to be formally named but belongs to the genus\u00a0Propostira\u00a0\u2013 was first\u00a0observed\u00a0by Professor Greg Anderson, a biomedical research scientist who is also a spider taxonomist\u00a0and photographer.\u00a0<\/p>\n

Lead researcher\u00a0Professor Ajay Narendra\u00a0of Macquarie University and postgraduate student Pranav Joshi then spent 10 days and nights in rainforest near Cooktown in far north Queensland\u00a0locating\u00a0the spiders, observing them in\u00a0detail\u00a0and capturing their behaviour using high-speed and infrared cameras.\u00a0<\/p>\n

\u201cIt\u2019s\u00a0very\u00a0unusual for a spider to feed on ants, because they\u2019re notoriously dangerous, and even more bizarre to find a spider that eats only one particular ant species,\u201d said Professor Narendra.\u00a0\u201cAnts have a range of chemical defences \u2013 including the ability to sting in some species \u2013 and they use alarm signals to rapidly recruit hundreds and even thousands of other ants as backup to overcome potential predators.\u201d\u00a0<\/p>\n

During the day, the ballista spider takes refuge on the underside of a leaf above an area where green tree ants are actively foraging. As night falls, the spider descends 50cm or\u00a0more to lay an anchor point on a leaf, a branch,\u00a0or the forest floor, then spends up to four hours engineering a vertical arrangement of 15-60 silk tension lines bundled together in a cone near the ground.\u00a0<\/p>\n

As\u00a0a final step, the spider wraps the cone with a thinner type of silk then rapidly retreats upwards. Within seconds, a green tree ant is attracted and reacts aggressively, biting the cone and detaching it from the anchor point.\u00a0<\/p>\n

With the snare thus sprung, the ant is\u00a0launched\u00a0more than 30cm upwards into the spider\u2019s core web at an acceleration of more than 1300 metres per second2. The spider waits for the ant to be fully entangled in its web before approaching and wrapping it with silk.\u00a0<\/p>\n

\u201cWe suspect during the final construction stage the spider adds a pheromone that specifically lures worker ants and induces an aggressive attack, triggering the snare,\u201d\u00a0said\u00a0Professor Narendra.\u00a0\u201cThis seems to be the only case where a spider\u2019s web is designed to catch a single prey species, and where the mechanism is triggered by the prey rather than by the predator.\u201d\u00a0<\/p>\n

Co-senior author Dr Jonas Wolff, who studies biomechanical properties of spider silk, travelled to Australia to observe the spider in the wild and took samples of its silk back to his lab at the University of Greifswald in Germany for detailed physical analysis, including scanning electron microscopy.\u00a0<\/p>\n

\u201cThe ballista spider\u2019s snare is bioengineered to store elastic energy in the silk and rapidly release it, giving it incredible instantaneous power density \u2013 greater than any other specialised silk-based biological catapults,\u201d said Professor Narendra. \u201cThe ants it preys on have adhesive pads on their feet, so the contraction of the bundle of tension lines has to overcome a force of many times the ant\u2019s body weight to lift it.\u201d\u00a0<\/p>\n

\u201cThe snare mechanism seems to have evolved as a highly specialised way of allowing the spider to \u2018pick off\u2019 potentially hazardous prey one at a time and transport them a safe distance\u00a0away\u00a0from ant trails and nests.\u201d\u00a0<\/p>\n

Method of Research<\/p>\n

Observational study<\/p>\n

Subject of Research<\/p>\n

Animals<\/p>\n

Article Title<\/p>\n

Ballistic high-powered spider webs overcome dangerous prey defenses<\/p>\n

Article Publication Date<\/p>\n

22-Jun-2026<\/p>\n

COI Statement<\/p>\n

The authors declare no competing interests.<\/p>\n

Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.<\/p>\n","protected":false},"excerpt":{"rendered":"image:\u00a0 A ballista spider (Propostira sp.) waits for a green tree ant (Oecophylla\u00a0smaragdina) to bite the cone of…\n","protected":false},"author":2,"featured_media":754208,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[7],"tags":[49,48,66],"class_list":["post-754207","post","type-post","status-publish","format-standard","has-post-thumbnail","category-science","tag-ca","tag-canada","tag-science"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/754207","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/comments?post=754207"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/posts\/754207\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media\/754208"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/media?parent=754207"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/categories?post=754207"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/ca\/wp-json\/wp\/v2\/tags?post=754207"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}