Overview
The Carnivorous Cave Sponge (Asbestopluma hypogea) upended scientific paradigms when discovered in a shallow submarine cave near Marseille, France, in 1995. While all sponges were historically considered passive suspension filter-feeders, this remarkable species evolved as an active carnivore. Trapped within nutrient-depleted dark caves that mimic the abyssal plain, it has completely abandoned water-filtering pores in favor of capturing live swimming crustaceans.
Biology and Physical Characteristics
Asbestopluma hypogea consists of a slender vertical pedicel anchored to cave rock, terminating in an ovoid body from which dozens of fine, lateral filaments radiate outward like a miniature candelabra. The sponge has lost its aquiferous canal system, choanocytes, and oscula. Instead, its outer surface is coated in millions of microscopic, Velcro-like hook spicules (anisochelae) that snag the hairy appendages of passing crustaceans.
Behavior and Ecology
When an unsuspecting mysid shrimp or amphipod brushes against a filament, the spicules instantly snare it. The sponge responds by migrating amoeboid cells around the struggling prey over several hours, completely enveloping the crustacean in an external digestive syncytium. Over several days, digestive enzymes dissolve the prey’s soft tissues before the cells reabsorb nutrients and rebuild lateral filaments.
Conservation and Human Impact
Classified as Vulnerable by the IUCN, Asbestopluma hypogea is endangered by its extreme ecological specialization. Its shallow cave populations survive only because cold winter waters become trapped in dead-end caves, creating a stable thermal refuge. Rising Mediterranean sea temperatures and unauthorized recreational cave diving that stirs up abrasive sediment directly threaten these fragile, ancient colonies.
Interesting Factoid
The Carnivorous Cave Sponge captures prey like living biological Velcro: its microscopic hooked silica spicules latch onto the bristles of small shrimp, after which sponge cells literally crawl over and engulf the prey alive.
Last updated: October 2026