The minke whale , or lesser rorqual, is a species complex of baleen whale. The Rorqual is the only similarly configured whale in the fossil record. The blue whale was once commonly referred to as "Sibbald's rorqual". It also yielded several marine mammals&colon; a rorqual, "Acrophoca", the sperm whale "Scaldicetus", and "Odobenocetops". Diunatans is an extinct genus of rorqual. "Rorqual" attacked the tug "Ursus" and a floating battery mounted on a lighter. HMS "Rorqual" (S02) was a "Porpoise"-class submarine launched in 1956. Lilljeborg, however, identified it as ""Balaenoptera robusta"", a species of rorqual. Though badly damaged, the floating battery opened fire and forced the "Rorqual" to dive. This collision punched a hole in "Endurance" but did not damage "Rorqual". NOAA subsequently sold "Gloria Michelle"'s predecessor "Rorqual" at public auction. "Diunatans" is the only known fossil rorqual from the North Sea. The collision punched a large hole in " Endurance's" hull but did not damage "Rorqual". In 1958, "Rorqual" experienced a fire. "Rorqual" had to dive deep to avoid it.