The Endangered Species Act is the major reason why Asian arowanas can't be legally imported into the U.S. A microchipped Asian arowana with CITES documentation would arguably be "legal" under the Lacey Act, because the CITES documentation would be evidence of compliance with Country of Origin laws. However, CITES documentation does not get you around the Endangered Species Act prohibitions.
The Asian arowana is specifically listed as an endangered species under the Endangered Species Act. Many other CITES species are protected through the Lacey Act alone without a separate listing under the ESA. They are two different, but related, regulatory schemes. Think of it as layers of protection, with ESA offering an additional layer.
The ESA is most known for its regulation of domestic species such as the snail darter, sea otter, spotted owl, and vernal pool crustaceans, aka fairy shrimp. Some of these species aren't protected by other regulatory methods.