Horned Stalked Jellyfish

Overview

The Horned Stalked Jellyfish (Lucernaria quadricornis) is a unique cnidarian that combines features of both polyps and medusae. Unlike free-swimming jellyfish, this species is semi-sessile, typically remaining attached to a substrate while using its tentacles to capture prey.

Appearance

This species features a distinctive, funnel-shaped body (calyx) that can reach up to 6 cm in width. It is anchored to surfaces by a flexible peduncle, or stalk, which is often longer than the calyx itself. The upper portion consists of eight arms arranged in four pairs, each tipped with a dense cluster of 100 to 140 tentacles. Its coloration is highly variable, ranging from translucent white or pale yellow to shades of brown, green, or red, providing effective camouflage against its surroundings.

Distribution & habitat

Lucernaria quadricornis is primarily found in the cold waters of the North Atlantic, North Pacific, and Arctic regions. It inhabits benthic environments, ranging from shallow intertidal pools and coastal areas to depths of over 500 meters. It is commonly found attached to hard substrates such as rocks or macroalgae, particularly kelp.

Biology & behavior

As a non-swimming predator, it relies on its nematocyst-laden tentacles to capture small invertebrates, including copepods, amphipods, and juvenile crustaceans. While it is generally stationary, it is capable of moving by detaching its stalk and creeping along the seafloor. The species follows a seasonal life cycle, with individuals reaching sexual maturity in the summer before reproducing and eventually dying off, leaving the next generation to overwinter.