Four rare and delicate sponges described

Four rare, beautiful and delicate sponges have been described by Queensland Museum scientists.

Found on seamounts off the coast of Queensland and Tasmania that rise from depths of 4 kilometers below the surface of the ocean, these rare sponges live atop these seamounts roughly 1 kilometer below the surface.

Dr. Merrick Ekins, Queensland Museum Network Collection Manager, Sessile Marine Invertebrates said the sponges had razor-sharp spicules that form nice little rosettes.

"These beautiful sponges are the first records of the genus Hamacantha (Vomerula) from the Australian Exclusive Economic Zone," Dr. Ekins said.

These four new species, bring the known species in the subgenus Vomerula to 26. The paper is published in the journal Zootaxa.

The new species are:

Hamacantha (Vomerula) novacula sp. nov. Ekins & Hooper

This is a fragile, lace-like, encrusting sponge was found attached to a rock and has a white and translucent look. It was named Hamacantha (Vomerula) novacula in reference to the extra sharp fimbria, which resembles a shaving knife. Novacula is a latin for sharp knife.

Hamacantha (Vomerula) melliflura sp. nov. Ekins & Hooper

This is another fragile, lace-like, encrusting sponge but was named Hamacantha (Vomerula) melliflura which means "flowing with honey," and was named for the flowing nature of the surface and the honeycombed texture of the sponge.

Hamacantha (Vomerula) ridleyi sp. nov. Ekins & Hooper

This fragile, encrusting sponge has a smooth surface without any visible oscules. It was named after Stuart Ridley, who has described many minute deep-water sponge species from the HMS Challenger and HMS Alert expeditions.

Hamacantha (Vomerula) levii sp. nov. Ekins & Hooper

This is a round, thin specimen that has a rough surface. It was named for Claude Lévi, who described many deep-water sponge species from the South Pacific.