Kassari Spider Moths

The spider moth is the only known spider-like creature to have two forms. When a spider moth hatches, it looks similar to a common jumping spider. The largest difference is an atypical swelling on its abdomen just beyond its waist where its wings will grow. Likewise, the colors are slightly different. While the spider moth has very deep brown and pale tan bands separated by thin white lines, the common jumping spider has a more stark black and white coloring. Finally, both sexes of spider moths have tan pedipalps.

In their other form, many people confuse spider moths with marsh carpet moths. The coloring of the two species is almost identical. On their forewings, they have scalloped stripes of deep brown and tan. The four wide bands are separated by thin white lines. Unlike those of the marsh carpet moths, these stipes form distinct V shapes. The spider moth's hind wings are tan with two scalloped lines: one dark brown and the other white. Unlike all moths, the spider moth has only a cephalothorax and an abdomen. However, the abdomen is long and thin in this form, which can cause confusion. It also retains its eight legs.

The spider moth is the only known arachnid-like invertebrate that undergoes metamorphosis. Not only that, but it both migrates and hibernates. No wonder the desert people celebrate these creatures.

This species starts its life in the wet lands on the southern edge of the Grand Lake. By hatching in early Maiden season, spider moth young gain additional time to grow. They quadruple in size in their first year. After that, these creatures' growth rate slows down. Most specimens grow only about the width of a strawberry seed each year. Voracious eaters, they spend most of their time awake hunting. When the weather starts to cool, spider moths in their second year or older will turn their attention to mating. Females will place their egg sack high in a tree. At the end of Dowager season, all spider moths will spin a cocoon and transform.

Unlike most arachnids, spider moths migrate across the Spine Mountains to the Black Desert. There they seek out acacia trees near dry seasonal streams. After finding a suitable location, they spin a thicker, stronger cocoon. Then they hibernate during the dry season.

When the maiden season rains finally come, the rising humidity wakes them up. They emerge from their cocoons and feast on the flurry of insect activity. Fattened up, they fly back to the wetlands on the other side of the spine mountains. The spider moths spin a third cocoon. In a matter of days, they change from winged creature back to their spider-like form. And thus the cycle repeats. Most of this species live for five years. While predators or accidents kill most, some grow too big for their lungs.

Kassari spider moth cocoons are where Kassari silk comes from. After the creatures have spun their homes in the acacia trees of the Black Desert, teams of pickers pluck them from the branches. Because the demand for the pale gold silk is high, many producers immediately place the cocoons in boiling vats. More traditional tribes cut open the fiber bundles to release the creatures inside. As a thank you for their silk, they give the emerging moths maggoty meat and allow them to go free. A few entrepreneurs are having success keeping the invertebrates in specially built enclosed tree gardens.

While it should be possible to simply unspool the spider moth cocoons like that of silk moths, the incredible thinness of the silk make this nearly impossible. Most Kussari silk fiber is spun similar to linen or wool. In the future, it may be possible to use modern lenses to help workers see the individual stands more clearly to unspool the silk.