New mycosporine-like amino acids (MAA) LC-343 (1) and mycosporine-ethanolamine (2) along with known MAAs asterina-330 (3) and shinorine (4) were isolated from the Micronesian marine sponge Lendenfeldia chondrodes. The structures of 1 and 2 were determined on the basis of their spectroscopic and spectrometric data as well as chemical degradation. LC-343 (1) is the first MAA possessing Nmethylated iminium substructure. Absorption maximum (lambda(max)) for each 2, 3, 4, and 1 was 310, 330, 332, and 343, respectively.