This monster's name is based on Rasalhague, the brightest star in the Zodiac constellation of Ophiuchus.
This monster's Japanese name, "Hawwa", is based on the original Arabic reading of Rasalhauge (رأس الحواء ra's al-ḥawwā').
The constellation and the astrological symbol for Ophiuchus (⛎︎) appears in the background of this card's artwork.
In astrology, Ophiuchus has sometimes been used in sidereal astrology as a thirteenth sign in addition to the twelve signs of the tropical Zodiac constellations.
This monster is depicted with a staff entwined with the golden image of a serpent, referencing how Ophiuchus is also known as the "serpent-bearer" constellation.
The above-mentioned fact also references the legend of Asclepius, the god of medicine and healing in Greek mythology, who is depicted wielding a rod entwined with a single serpent. After he was smote for resurrecting souls of the dead, Zeus, the king of the Olympian Gods, placed his body among the stars as the constellation, Ophiuchus.
Afterwards, "Evilswarm Kerykeion" likely transforms into its upgraded "Constellar" form, "Constellar Caduceus". This is based on how both monsters highly resemble each other, how they are named after the staff entwined with two serpents, and how the upper portion of the staff wielded by "Constellar Caduceus" highly resembles the logo of the "lswarm" archetype.