The Science and Research Center has discovered that the mistletoe that grows out of a Luciales egg supplies a portion of the nutrients the developing Luciales needs to grow. It also causes the spot of color on the egg to flicker and glow making it look like a candle flame. Because of this some people will use Luciales eggs to decorate their homes for Christmas.
The Luciales has a symbiotic relationship with the mistletoe that grows from its body. Like it did for the egg, the mistletoe provides some of the energy for it's host. This allows the Luciales to eat less food than other creatures of its size. A trait that helps them greatly since they make their homes in some of the coldest regions of Ark. It has been theorized that the mistletoe that grows around the head of the Luciales is what causes the points of their horns to glow.
The Luciales is a very shy creature. In the wild they will try to avoid contact with humans. Even tamed Luciales are uncomfortable when around more than one or two people. The only exception to this rule is the night of the winter solstice. On the night of the winter solstice, Luciales will gather together and await the coming dawn. In the hours before dawn they will stand on their hind legs and begin to "sing", a sort of melodic howl. They will continue to sing until the sun rises, at which point they will disperse, only to repeat the process a year latter.
So far the Science and Research Center hasn't found an explanation for this behavior. Their best guess is that the Luciales are celebrating the return of longer daylight hours. There is an old Arkian tradition surrounding the Luciales and their celebration of the return of the sun. One member of each family dresses themselves in a white gown and mistletoe or holly headdress, taking a lit candle they will join with the Luciales and sing with them for part of the night.