Cryptococcus curvatus is a fungus species. It is an extremophile found in cold-seep sites. It is oleaginous, and uses the sugars in cellulose for the growth and production of storage triglycerides. <Takishita et al. (2010) Molecular evidence that phylogenetically diverged ciliates are active in microbial mats of deep-sea cold-seep sediment. 57(1): 76-86 </ref> This species has been extensively studied in relationship to lipids. It can uptake both glucose and xylose simultaneously. When grown in old oil with high levels of polymerized triglyceride, the cell wall transforms from being smooth to having hair or wart-like protuberances which are believed to assist in lipid uptake.