T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network


Caterpillars

Caterpillars are the larval form of members of the order Lepidoptera (the insect order comprising butterflies and moths). They are mostly herbivorous in food habit, although some species are insectivorous. Caterpillars are voracious feeders and many of them are considered to be pests in agriculture. Many moth species are better known in their caterpillar stages because of the damage they cause to fruits and other agricultural produce.

Many animals feed on caterpillars as they are rich in protein. As a result caterpillars have evolved various means of defense. The appearance of a caterpillar can often repel a predator: its markings and certain body parts can make it seem poisonous, or bigger in size and thus threatening, or non-edible. Some types of caterpillars are indeed poisonous.
More aggressive self-defense measures are taken by some caterpillars. These measures include having spiny bristles or long fine hair-like setae with detachable tips that will irritate by lodging in the skin or mucous membranes. Other caterpillars acquire toxins from their host plants that render them unpalatable to most of their predators. The most aggressive caterpillar defenses are bristles associated with venom glands. These bristles are called urticating hairs
Plants contain toxins which protect them from herbivores, but some caterpillars have evolved countermeasures which enable them to eat the leaves of such toxic plants. In addition to being unaffected by the poison, the caterpillars sequester it in their body, making them highly toxic to predators. The chemicals are also carried on into the adult stages. These toxic species, such as the Cinnabar moth (Tyria jacobaeae) and monarch (Danaus plexippus) caterpillars, usually advertise themselves with the danger colors of red, yellow and black, often in bright stripes (see aposematism). Any predator that attempts to eat a caterpillar with an aggressive defense mechanism will learn and avoid future attempts.
Some caterpillars regurgitate acidic digestive juices at attacking enemies. Many papilionid larvae produce bad smells from extrudable glands called osmeteria.



Caterpillars of moths and butterfies.


Caterpillar of the Bamboo moth (Artona martini)


Caterpillar of the Cinnabar moth (Tyria jacobaeae)


Caterpillar of Common Bag Moth (Liothula omnivora)


Caterpillar of the Common Forest Looper (Pseudocoremia suavis)   


Caterpillar of the Greasy Cutworm (Agrotis ipsilon)


Caterpillar of the White Butterfly (Pieris rapae)


Caterpillar of the Cabbage Looper (Trichoplusia ni) 


Caterpillar of the Guava moth ( Coscinoptycha improbana)


Caterpillar of the Gum Emperor Moth (Opodiphthera eucalypti)


Caterpillat of the Indian Meal Moth (Plodia interpunctella)


Caterpillar of the Kawakawa Looper (Cleora scriptaria) 


Caterpillar of the Kowhai moth (Uresiphita polygonalis maorialis)


Caterpillar of the Monarch Butterfly (Danaus plexippus) 


Caterpillar of the Magpie Moth (Nyctemera  annulata) 


Caterpillar of the Porina moth) Wiseana spp.