Owlfly eggs in spiral formation


Although owlflies (Neuroptera: Ascalaphidae) are diurnal predators, I frequently see them at night resting on thin stems and branches with their bright orange eggs. The eggs of this species are always in a spiral formation possibly mimicking a spore-like arrangement, meanwhile other neuropterans typically lay eggs in straight rows. It would be fascinating to watch how an owlfly works its way around a branch when ovipositing, so hopefully I will be lucky to observe that. If you look closely at the base of the forewings there are biting midges feeding on the hemolymph flowing through those thicker veins.

Some owflies have bipartite eyes with a dorso-frontal region that is UV-sensitive and a ventro-lateral region with high sensitivity to blue-green wavelengths. This highly specialized eye morphology allows them to have heightened contrast perception of small flying insect prey while retaining high spatial resolution in both clear and cloudy sky conditions. Although they are not as maneuverable as dragonflies since their wings move synchronously (pairs on each side of the body are physiologically coupled), they are effective aerial hunters. Some even adopt a resting posture with their wings spread out, superficially resembling a dragonfly. I have never seen an adult owlfly hunt (or even seen a picture of one with prey actually) – another behavior I would love to observe.

Owlfly larvae are also predators, like a free-roaming antlion without the need of a pit. They are cryptic and sit with their jaws agape, ready to ambush unsuspecting prey that strolls by. Hopefully these eggs will hatch sometime in the next few weeks and I can share photos of the first instar larvae.

Photographed in situ [1]


Leave a Reply

close-alt close collapse comment ellipsis expand gallery heart lock menu next pinned previous reply search share star