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Updated: Aug 11, 2026

Wireless Electrophysiological Recording of Neurons by Movable Tetrodes in Freely Swimming Fish
Published on: November 26, 2019
Ecological functions of tetrodotoxin in a deadly polyclad flatworm
Raphael Ritson-Williams1, Mari Yotsu-Yamashita, Valerie J Paul
1Smithsonian Marine Station at Fort Pierce, Fort Pierce, FL 34949, USA. williams@sms.si.edu
Abstract:
The deadly neurotoxin tetrodotoxin (TTX) is found in a variety of animal phyla and, because of its toxicity, is most often assumed to deter predation. On the tropical Pacific island of Guam, we found an undescribed flatworm (planocerid sp. 1) that contains high levels of TTX and its analogs. Through ecological experiments, we show that TTXs do not protect these flatworms from some predators but instead are used to capture mobile prey. TTX is known to have multiple ecological functions, which has probably led to its widespread presence among prokaryotes and at least 10 metazoan phyla.
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