Wingworms

Wingworms are a lineage of flying binucleid worms.

Anatomy
Wingworms are unusual among fauna in that their eyes are on their abdomen. Many species fly backwards as a result. Their wings are attached to their cephalic segment. While wingworms ancestrally had many legs, eight on their cephalic segment and two on each abdominal segment, these along with their eyes have been inexplicably lost many times independently.

Descendants of the Twelve-Winged Worm have unidirectional tracheae and semi-active respiration; air enters through tiny spiracles on their face, circulates through the whole body, and exits out near the cloaca. Earlier forms have simpler insect-like tracheae and entirely passive respiration.

The legs of wingworms, when present, are generally soft and unsclerotized, more comparable to the limbs of an annelid or a velvet worm than to those of an insect.

Quite unlike insects, wingworms do not have a larval or nymph stage. Juveniles hatch already winged and on most species can fly once their wings are dry. A noteworthy exception is batworms, which lack the flight membrane between their wings until they are older.

Precursors
Wingworms are a type of binucleid worm, specifically derived from beach thornworms. Their closest living relatives are stumpworms such as scuttlecrabs and saucebacks, and likewise the wing segment of wingworms is homologous with the hip-bearing "sauce" of stumpworms. The first recognizable precursors to wingworms, the silkworms, evolved in the Ovian period. The first non-wingworm silkworm to have what would later become the wings was the Feathered Silkworm, which appeared over 100 million years later in the Rhodixian period. Flightless derivatives of the feathered silkworm and later the Gliding Sagworm also existed and saw great success, however all non-wingworm silkworms would eventually die out as a result of the devastating snowball event of the Bloodian period.

The first true wingworm, the wingworm itself, appeared in the Irinyan period.