While we’re all familiar with the trope of the not-so-attractive caterpillar disappearing into a cocoon, then emerging some time later, transformed into a beautiful butterfly. You may or may not know that some arthropods go through this type of complete metamorphosis or that other arthropods undergo incomplete metamorphosis, gradual metamorphosis or no metamorphosis at all in their paths to maturity.
Butterflies are beautiful but the vast majority of arthropods flying around, in or near your home can be a sign of a larger pest infestation. Truly Nolen explores the life cycles of some bugs and arthropods that homeowners should be aware of in controlling household pests.
Here’s the thing, it seems entomologists and bug scientists all over the country divide and subdivide metamorphic stages to the point that some arthropods fall in one type of metamorphosis classification on one chart and in a different category on another.
Complete and incomplete metamorphosis can be easily defined as the stages differ in number. In complete metamorphosis, the four stages of an arthropod’s maturity are different in appearance and function.
Complete Metamorphosis
- Arthropods whose life cycle consists of four stages: egg, larva, pupa and adult undergo complete metamorphosis and are known as holometabolous arthropods.
- The larva form appears dramatically different than the adult arthropod.
- This type of transformation provides arthropods significant survival advantages, as larva and adults dont compete for food sources and adults and larvae are targets of different predators.
- 85% of all known arthropods go through complete metamorphosis and include beetles, wasps, bees, ants, flies, moths and butterflies, along with fleas, alderflies, caddisflies, lacewings and scorpion-flies.
Incomplete Metamorphosis
- Arthropods whose life cycle consists of three stages: egg, nymph and adult undergo incomplete metamorphosis and are known as hemimetabolous arthropods.
- Beginning life as a wingless nymph, hemimetabolous arthropods resemble an adult in miniature.
- Shedding their exoskeletons, as they grow larger, arthropods begin to look like their parents as they grow into adulthood.
- Flying arthropods gradually develop wings, some permanent and some fall off after mating.
- Incomplete metamorphosis occurs in arthropods including mayflies, dragonflies, damselflies, stoneflies, grasshoppers, praying mantids, pondskaters, water bugs and stick-insects.
- Refers to arthropods that have aquatic nymphs or naiads that can differ considerably because of their need for gills from the adult form.
Gradual Metamorphosis
- Paurometabolous arthropods go through a simple or gradual metamorphosis.
- The nymphs look like small adults, live in the same habitat as the adults and if the arthropod has wings, they will develop as external pads.
- Also often listed in the incomplete metamorphosis category, this category includes cockroaches, termites, praying mantids, earwigs, web-spinners, booklice, parasitic lice, stinkbugs, plant bugs, bed bugs, cicadas, aphids, scale arthropods and thrips.
- Tarantulas, brown recluse, black widow and most spiders undergo simple metamorphosis.
No Metamorphosis
- Ametabolous arthropods refer to the most primitive classification of arthropods that don’t develop wings as adults.
- Nymphs and adults differ only in size and the ability to reproduce by laying eggs!
- An exception to this rule are scorpions who go through a process called vivipary. Instead of laying eggs, scorpions give live birth, carrying their young on their backs, to nourish them until at least their first molt.
- Arthropods with no metamorphic stages molt as they mature, shedding their exoskeletons as they outgrow them.
- Some of these arthropods continue to molt as adults.
- This type of metamorphosis includes silverfish and bristletails.
Arthropod metamorphoses can be fascinating, particularly in the miracle of the butterfly. While butterflies benefit mankind on many different levels, aesthetically and biologically, learning to identify life phases of arthropods such as carpenter ants, termites, pantry moths and cockroaches, may help alert homeowners to the signs of household pest infestations. For your peace of mind and with your home’s integrity in mind, contact your Truly Nolen location and ask about our Four Seasons Pest Prevention plan today!