Ostrinia furnacalis
common name Asian corn borer
found in Asia and feeds mainly on corn crop
This moth exhibits unique acoustic mimicry of a predator by mirroring the echolocation calls of bats in order to temporarily paralyze female moths and make it easier to mate.
The larvae work their way through the host plant (typically maize), by beginning to feed on the underside, or whorl, of the leaves. Younger instars typically feed on the tassel of the plant, and then move on to feed in the ear. There they feed on the silk and kernels of the corn plant. Later instar stages begin to make their way into the plant by feeding on stalks. This allows them to be able to form pupae within the stems of the plant. Additionally, if the food supply of the current plant is limited, the larvae create silk that serves as a connection between plants so that they can travel from plant to plant. They are then transported by the wind through a process known as ballooning, where the strands catch the wind in order to transport the larvae. They also use existing silk strand connections to other plants as trails where they can hope to find a better food source that can also serve them as a location for pupation.
After 3 to 4 weeks, the caterpillar larvae transform into pupae for 6 to 9 days in a cocoon in the soil or stem of the plant, before becoming moths.
The adult moths live for 10 to 24 days. During this lifetime, female moths can lay up to 1500 eggs.
During courtship, the male Asian corn borer produces an ultrasound call by rubbing scales on its wings against scales on its thorax. This ultrasound call acoustically mimics that of the bat echolocation call. The males take advantage of this predator cue in order to seduce a mate via sensory trapping, which are signals that mimic those of a predator in order to exploit the adaptive, neural responses of signal receivers. The female responds to this signal by becoming motionless, making it easier for males to mate since they are not effective at copulating.
This species has been known to have a skewed sex ratio occurring at a low frequency. The skewed ratio is caused by a parasitic bacterial infection, Wolbachia, that feminizes the male offspring.
This is supported by evidence that the antibiotic application of tetracycline, an agent that kills Wolbachia, produces all-male offspring broods. Additionally, the female-biased sex ratio can be maternally inherited.
The adult moths are known for being strong, nocturnal fliers, and can fly up to several miles in a single night. Reasons for these long flights are speculated to be because of mating, since there is a negative correlation between flight duration and egg production.
The moth larva does most of the damage by feeding on almost all parts of the plant. It destroys the fruit when it bores into the ear to feed on the silk and kernels, and the stem when it creates a cocoon for pupation.
Most nocturnally active moths are attracted to light, a phenomenon known as positive phototaxis.
sources rich in UV greatly increased moth attraction to light
Insects, and especially moths, are particularly sensitive to the UV part of the electromagnetic spectrum.
A common theory is that moths are attracted to the moon, and therefore they should fly higher on moonlit nights. A better theory is that moths can use the moon or stars to orientate, and that a moth adjusts its flying track to keep the light source at a constant angle to the eye. However, whilst rays from a celestial source would all be seen as parallel, those from a lamp radiate all around.
Accordingly, a moth on the wing would constantly turn inwards to keep itself at a constant angle to the light, ending up in a spiralling path which would make it eventually collide with the lamp. However, moths rarely exhibit such geometric trajectories, but rather take circuitous routes when coming to light, making loops and coils perhaps due to a compromise with escape responses or disturbance by wind plumes. Moths are also affected by a general phenomenon known as dorsal light reaction. Most flying animals, in fact, tend to keep the lighter sky above them (they do not fly upside down!), and will therefore also dip down when closing in on an artificial source that they then confuse with the sky light.
The moth’s behavior of keeping a constant angle between its flight trajectory and the light rays emitted by an artificial source would then enable a moth to arrive at a single brightest light source perceived from a matter of kilometers as if it were a star.