A new cyclodepsipeptide comprised of three amino acids, and an oxy-trimethyl-nonanoyl group, has been characterized which has antifungal and anthelminthic bioactivity. We have encountered several soft-bodied sponges, during past Tonga - Fiji expeditions, whose crude extracts are active against yeast. As one example, the crude extract of a small 1984 collection of a Jaspis sp. which was bright orange (order. Astrophorida; family, Jaspidae), from the Island of Benga, Fiji, showed a 33 mm growth inhibition zone, at 100 μL, against Candida albicans. Recollection of this sponge yielded Jasplakinolide (1) which showed selective antimicrobial activity. A minimum inhibition concentration (mic) and minimum lethal concentration (mlc) of 25 μg/mL each was observed against C. albicans, and the in vivo topical activity of a 2% solution of 1 against a Candida vaginal infection in mice was comparable to that of miconazole nitrate, whereas no activity was observed, at 100 μg/13 mm disk, against Pseudomonas aeruginosa, S. aureus, Streptococcus pyogenes, Mycoplasma sp., or T. mentagrophytes. Jasplakinolide exhibited an in vitro ED50 < 1 μg/ml against the nematode Nippostrongylus braziliensis, and complete in vitro cell toxicity, against larynx epithelial carcinoma at 0.32 μg/ml, and human embryonic lung at 0.01 ng/ml. The chemical structure of Jasplakinolide (1) will now be reported.