title: A modified view on octocorals: Heteroxenia fuscescens nematocysts are diverse, featuring both an ancestral and a novel type.
abstract: Cnidarians are characterized by the presence of stinging cells containing nematocysts, a sophisticated injection system targeted mainly at prey-capture and defense. In the anthozoan subclass Octocorallia nematocytes have been considered to exist only in low numbers, to be small, and all of the ancestral atrichous-isorhiza type. This study, in contrast, revealed numerous nematocytes in the octocoral Heteroxenia fuscescens. The study demonstrates the applicability of cresyl-violet dye for differential staining and stimulating discharge of the nematocysts. In addition to the atrichous isorhiza-type of nematocysts, a novel type of macrobasic-mastigophore nematocysts was found, featuring a shaft, uniquely comprised of three loops and densely packed arrow-like spines. In contrast to the view that octocorals possess a single type of nematocyst, Heteroxenia fuscescens features two distinct types, indicating for the first time the diversification and complexity of nematocysts for Octocorallia.
authors.affiliation: Department of Zoology, George S Wise Faculty of Life Sciences, Tel Aviv University, Ramat Aviv, Tel Aviv, Israel.
authors.forename: Chen
authors.initials: C
authors.lastname: Yoffe
authors.forename: Tamar
authors.initials: T
authors.lastname: Lotan
authors.forename: Yehuda
authors.initials: Y
authors.lastname: Benayhau
mesh_terms: D000818:Animals; D037421:Anthozoa; D003063:Cnidaria; D058894:Nematocyst