The Dipterantula

Harpoonjaw mosquitoes, in comparison with their whiplasher cousins, have declined greatly over the past million years or so. With less potent venom, poor flight skills, and less versatile mouthparts, the Cultroculicinae have, as a whole, failed to compete with other insectivorous flies. In particular, the derived Pugilopsids have overtaken many niches once held by predatory harpoonjaws, pushing them into minor roles in their ecosystems. Within another few hundred thousand years, it's likely that the clade will be all but extinct. But not all members of the subfamily will share this fate. Locust reapers have survived by switching to a vegan diet, avoiding the fate of their carnivorous relatives. Only one other genus, descended from a rare and specialized offshoot of the harpoonjaw clade, is also doing well for itself.

Stowaways were a species of dustfly-mimics native to swampy, low-nitrogen habitats in the Mid-to-Late Muricene. Their camouflage allowed them to blend in with the swarms of nectar-drinking Saccharoculicids they fed on and to evade the watchful eye of arboreal isopods. Over time, dustflies evolved to grow larger and more distinctive, and the stowaways found it harder and harder to convincingly mimic their targets. In response, their strategy changed; instead of following their prey, they adapted to wait patiently, silently, and without moving on the leaf of a sweetstalk. Taking great care to avoid drawing attention to themselves, the Stalking Stowaway (Vanidiculex patiens), whose temporal range spanned the Great Decarbonization, became expert ambushers.

This species slowly lost the use of its wings as a flight apparatus, as it spent nearly all its time motionless. When it needed to move to a new plant, it simply walked on the ground, relying on its venom to keep threats at bay. The strength of its Flagelloculicin-based toxins increased more than fivefold, facilitating quick, efficient kills. As the Arthrocene dawned, sweetstalks rose to their current prominent position in the global biosphere, bringing this new breed of stowaway along for the ride. 

Today, the descendants of the stalking stowaway are known as Dipterantulas (Arachnoculex). They now feed on a wider array of insects and crustaceans, with many different species each specializing on a particular type of prey. Their sharp, barbed maxillae serve as fangs, injecting a potent slurry of venom that rapidly dissolves flesh. Dipterantula wings, though useless for flying, make effective armor, absorbing shocks and resisting counterattacks from struggling targets. These structures can also serve a display purpose, for while their upper surfaces are usually a drab, mottled brown, their normally-hidden undersides are often adorned with patterns of red, silver, and gold. When a male decides to pursue a potential mate, he lifts his wings and shows off the bright metallic colors beneath. The female will only choose the best of the best, as she will soon make an immense investment into her offspring's future.

One of the only occasions when dipterantulas venture out into the open is when females lay their eggs. For those living in drier areas, this can be a days-long trek across over a kilometer of dangerous territory, far from the safety of the lush sweetstalk thickets they normally call home. Finally, upon reaching a suitable pond or puddle, about 150 eggs are laid, and the survivors - usually about 30% of those who began the journey - retreat to a safer location.