 Its closest relatives are the two species currently in "Deckenia", both of which are found in East Africa.Several hypotheses have been published to explain how "Seychellum" reached its isolated location, including submerged "land bridges" and ancient vicariance, although some means of transport across the open ocean is considered the most likely explanation.Adults are dark yellow to brown in colour, and have a quadrangular carapace with a width of around .