Bryde's whale or Bryde's whale complex (/bruːdə/BREW-də) putatively comprises two species of rorqual and maybe three. The "complex" means the number and classification remains unclear because of a lack of definitive information and research. The common Bryde's whale (Balaenoptera brydei, Olsen, 1913), a larger form that occurs worldwide in warm temperate and tropical waters, and the sittang or Eden's whale (B. edeni, Anderson, 1879) a smaller form that may be restricted to the Indo-Pacific. There is also a smaller, coastal form of B. brydei off southern Africa, and perhaps another form in the Indo-Pacific that differs in skull morphology, tentatively referred to as the Indo-Pacific Bryde's whale. The recently described Omura's whale (B. omurai, Wada et al. 2003), was formerly considered a "pygmy" form of Bryde's, but is now recognized as a distinct species.