[8][9][10] Below is a cladogram based on a 2018 tip dating study by Lee & Yates simultaneously using morphological, molecular (DNA sequencing), and stratigraphic (fossil age) data,[9] as revised by the 2021 Hekkala et al. paleogenomics study using DNA extracted from the extinct Voay.

It can stay submerged underwater for more than 30 minutes, and can reach speeds of up to 30 km/h (19 mph) in short bursts.

[6][15] Other countries where it is found include Mauritania, Benin, Liberia, Guinea-Bissau, Nigeria, Niger, Cameroon, Chad, Sierra Leone, the Central African Republic, Equatorial Guinea, Senegal, Mali, Guinea, Gambia, Burkina Faso, Ghana, Gabon, Togo, Ivory Coast and the Republic of Congo.

[6] As late as the 1920s, museums continued to obtain West African crocodile specimens from the White Nile, but today the species has disappeared from this river.

[4] In a study of habitat use by the three crocodile species in Liberia (West African, slender-snouted and dwarf), it was found that the West African crocodile typically occupied larger, more open waterways consisting of river basins and mangrove swamps, and was the species most tolerant of brackish waters.

[19] Mauritanian traditional peoples who live in close proximity to West African crocodiles revere them and protect them from harm.

[16] The people of ancient Egypt worshiped Sobek, a crocodile-god associated with fertility, protection, and the power of the pharaoh.

C. suchus was known to be more docile than the Nile crocodile and was chosen by the ancient Egyptians for spiritual rites, including mummification.

DNA testing found that all sampled mummified crocodiles from the grotto of Thebes, grotto of Samoun, and Upper Egypt belonged to this species[6] whereas the ones from a burial pit at Qubbet el-Hawa are believed on the basis of anatomy to consist of a mix of the two species.

Priests were aware of the difference between the two species, C. suchus being smaller and more docile, making it easier to catch and tame.