Page "Onychophora" Paragraph 65

Onychophora probably do not primarily use vision to detect their prey ; although their tiny eyes do have a good image-forming capacity, their forward vision is obscured by their antennae ; their nocturnal habit also limits the utility of eyesight.

Air currents, formed by prey motion, are thought to be the primary mode of locating prey ; the role of scent, if any, is unclear.

The animals literally creep up on their prey, with their smooth, gradual and fluid movement escaping detection by predators.

Once they reach their prey, they touch it very softly with their antennae to assess its size and nutritional value.

After each poke, the antenna is hastily retracted to avoid detection by the prey individual.

This investigation may last anywhere upwards of ten seconds, until the velvet worm makes a decision on whether to attack it — or until it disturbs the prey and flees.

Hungry Onychophora spend less time investigating their prey and are quicker to apply their slime.

Once slime has been squirted, Onychophora will stop at nothing to hound down and devour their prey, in order to recoup the energetic investment.

They have been observed to spend up to ten minutes searching for removed prey, after which they return to their slime to eat it.

In the case of smaller prey, they may opt not to slime it at all.