''Anoxycalyx joubini'' is a species of Antarctic

sponge Sponges, the members of the phylum Porifera (; meaning 'pore bearer'), are a basal animal clade as a sister of the diploblasts. They are multicellular organisms that have bodies full of pores and channels allowing water to circulate throug ...

. The species may have an extremely long lifespan, with estimates of up to 1,500 years. ''A. joubini'' occurs in deeper waters than the similar species ''

Cinachyra antarctica ''Cinachyra antarctica'' is a species of antarctic sponge belonging to the family Tetillidae Tetillidae is a family of marine sponges. Tetillids are more or less spherical sponges (sometimes referred to as golf ball sponges) which are found c ...

'', which is also very long-lived. Antarctic sponges live at below the surface, in extremely cold temperatures and constant pressure. This may slow down their growth rate and other biological processes because one caught specimen of ''A. joubini,'' did not show any growth in a span of 10 years.

References

Hexactinellida Animals described in 1916 Marine fauna of Antarctica {{Porifera-stub