A. elongatus may refer to: Abacetus elongatus, a ground beetle Abatus elongatus, a synonym of Abatus koehleri, a sea urchin Aborichthys elongatus, a freshwater fish found in India Acheilognathus elongatus, the elongate bitterling, a freshwater fish found in China Adventor elongatus, the visitor, a marine fish found in the Pacific Ocean along the coasts of Papua New Guinea and Australia Afristreptaxis elongatus, a land snail found in Africa Agabus elongatus, a predaceous diving beetle found in North America and the Palearctic Aglymbus elongatus, a predaceous diving beetle Alcichthys elongatus, a marine fish found in the northwestern Pacific Ocean Allosmerus elongatus, a marine fish found in the northeastern Pacific Ocean Ambassis elongatus, the yellow-fin perchlet, a freshwater fish found in Australia Amphiglossus elongatus, a synonym of Flexiseps elongatus, a skink found in Madagascar Anisopodus elongatus, a longhorn beetle Anthonomus elongatus, a weevil found in North America Archips elongatus, a moth found in China Argentinolycus elongatus, a marine fish found off southeast South America Artocarpus elongatus, a synonym of Sloetia elongata, a tree native to southeast Asia Aster elongatus, a synonym of Solidago elongata, a plant found in North America Austropyrgus elongatus, a freshwater snail found in Tasmania Avitomyrmex elongatus, a prehistoric bulldog ant