Hence, they are the first Spirit monsters that do not strictly have to return to the hand the turn they are Summoned, though as mentioned, this is dependent on how they were Summoned.
"Andro-" is the Greek root for man or masculine, showing that Andro Sphinx is the masculine form of the two sphinxes.
The first part of Criosphinx's name, "Crios", is Greek, and roughly translates to "male goat".
The other series is centered on the summoning of Theinen the Great Sphinx, and are used by Anubis in the Yu-Gi-Oh! Movie. One series of Sphinxes supports flip summoning and is lead by Exxod, Master of the Guard. Sphinxes are a series of Rock-type Monsters based on the Egyptian Sphinx but In Name Only, in general they are centaur-like beings that take cues from several animals.