Sepioteuthis, commonly known as reef squids or oval squids, is a genus of pencil squid. Reef squids are easily recognizable by their large rounded fins that extend along almost the entire length of their mantles, giving them a superficial resemblance to cuttlefish.
Three species are currently recognized, though S. australis and S. lessoniana are believed to be cryptic species complexes.
An additional species, S. loliginiformis, was described in 1828, but its validity is questionable. However, if the species turns out to be the same as S. australis or S. lessoniana, S. loliginiformis would be the senior synonym and replace the younger name currently in use.