Harp Sponge

Chondrocladia is a genus of carnivorous tree sponges of the family Cladorhizidae.^[3] 
Thirty-three named species are placed in this genus at present, but at least two additional undescribed ones are known to exist, while some of the described ones are known only from a few specimens or (e.g. the enigmatic Chondrocladia occulta) just a single one, and their validity and/or placement in Chondrocladia is doubtful. Chondrocladia sponges are stipitate, with a stalk frequently anchored in the substrate by rhizoids and an egg-shaped body, sometimes with branches that end in inflatable spheres.^[5][6]
Fossils assignable to this genus are known since the Pleistocene,^[7] less than two million years ago. However, given its deep sea habitat, Chondrocladia may well have been around for much longer – it existed perhaps as early as the Mesozoic Era, as characteristic spicules (termed “microcricorhabds” or “trochirhabds”), almost identical to those of some living Chondrocladia, are known from Early Jurassic rocks almost two hundred million years old.^[6]
Carnivory
Carnivorous sponges, which use hooked spicules to capture small crustaceans, have been known only since 1995, when Asbestopluma hypogea, another genus of the family Cladorhizidae, was identified in Mediterranean sea caves offshore La Ciotat (France) by Jean Vacelet and Nicole Boury-Esnault.^[10] Carnivory has since turned out to be common and typical for this sponge family.^[11][4] Unlike their relatives, Chondrocladia still possesses the water flow system and choanocytes typical of sponges, albeit highly modified to inflate balloon-like structures that are used for capturing prey.^[4][6]