Overview
Cruising slowly through the perpetual midnight of the global bathypelagic ocean, the Dinner Plate Jellyfish (Solmissus incisa) is one of the deep ocean’s most formidable yet delicate gelatinous predators. Belonging to the hydrozoan order Narcomedusae, this species is named for its flat, circular, disc-shaped swimming bell that resembles an ornate glass dining plate floating weightlessly in space. Unlike common surface jellyfish that drag trailing tentacles behind them as they swim, Solmissus incisa carries its rigid, needle-like tentacles arched upward and forward, creating an inescapable sensory cage that hunts other gelatinous marine life.
Biology and Physical Characteristics
Solmissus incisa possesses a transparent to milky-white translucent umbrella characterized by a thickened central disc surrounded by 20 to 40 distinct marginal lobes. Projecting outward from above the bell margin are stiff, radiating tentacles composed of solid endodermal cords, held perpetually aloft in an active hunting array. The central underside is dominated by a broad, highly distensible mouth capable of stretching to engulf soft-bodied prey nearly equal to its own diameter. It lacks bulbous marginal tentacles or veils, relying on coordinated contractions of its radial muscle rings for propulsion.
Behavior and Ecology
Solmissus incisa is a specialized gelatinous carnivore (gelatinivore) that preys almost exclusively on other deep-sea jellies, including ctenophores, colonial siphonophores, salps, and appendicularians. By swimming with its stiff tentacles thrust forward into undisturbed water ahead of its bell, it detects minute hydrodynamic disturbances generated by unwary pelagic organisms. Upon contact, thousands of specialized penetrant nematocysts fire simultaneously, subduing prey before the flexible marginal lappets curl inward to transfer the captured organism directly into the central digestive pouch.
Conservation and Human Impact
Inhabiting remote depths exceeding 1,000 meters across every major ocean basin, Solmissus incisa experiences minimal direct interference from human activities. However, it plays an indispensable trophic role as a top gelatinous regulator in the twilight and midnight zones, preventing overpopulation of opportunistic filter-feeding tunicates. Deep-sea research initiatives led by institutes like MBARI continuously record this species to investigate the impacts of expanding oceanic oxygen minimum zones on pelagic food webs.
Interesting Factoid
Instead of trailing its tentacles behind it like most jellyfish, the Dinner Plate Jellyfish swims with its stiff tentacles held stiffly forward and upward, like a set of sensory radar antennas sweeping the dark water for prey!
Last updated: October 2026