A brief look at Nocturnal Insects

Most living things (insects included) are diurnal creatures—being active during the day and disappearing as soon as dusk sets in. Others, however, are the exact opposite, including insects that are nocturnal; those to be found sleeping or remaining inactive during the day and being most active at night. Some have eyes that are sensitive to light and are able to see better in darkness while others are nocturnally adapted to avoid predation and excessive exposure to sunshine.

These nocturnal insects have highly developed features that make them able to indulge in biological processes at night or in darkness. They are at times classified into two distinctive groups—those that are positively phototaxic—attracted by light and tend to fly toward it or in relation to it (whether it is the moon or a street lamp) and the negatively phototaxic ones that tend to move away from or avoid illumination altogether.


Also known as true crickets, these are nocturnal insects that are similar to the grasshopper in appearance and are often mistaken thus, but aren’t. While grasshoppers are strictly diurnal, crickets are nocturnal.

They belong to the family Tettigoniidae (in which katydids or bush crickets also belong) and are evidently nocturnal. True crickets, like other insects, are cold-blooded and able to take on the temperature of their surrounding.

They feed mostly on organic materials and are prone to feeding on other crickets that are crippled when no other source of food is available.


Not all moths are nocturnal, but majority of them are. These are the ones which tend to be attracted by artificial lights and can be found hovering around them, which weakens that and causes their death at times.

Moths of this nature are classified into the family Tineidae and are commonly considered as pests due to their propensity to devouring things ranging from cloths to crops—fruits in particular.


Like moths, some fireflies are also diurnal. But the most common ones are nocturnal, and widely known for their ability to emit light, which is due to a chemical process known as bioluminescence. Put another way, fireflies have light-emitting organs that are responsible for this luminosity.

When in the larvae stage, this luminosity is still evident, hence the name “glow worms” that is given to fireflies in the making. These glow worms contain chemicals that are harmful to predators, and their glowing or emission of light is supposed to be a warning to would be attackers.


Earwigs are most active at night and hidden for most of the day. Like some species of moths, they are also highly destructive and able to feed on foliage, flowers, and crops.

They have the biologically adapted feature of being flat and hence are able to squeeze themselves into tight crevices in which they stay during daylight to await nightfall.


Mosquitoes are arguably the most harmful of all nocturnal insects. The Anopheles mosquito is a carrier of malaria and able to infect humans upon biting them.

They belong to the family Culicidae and feed on blood from living vertebrates. The female, in particular, needs blood as nutrient to aid egg production.