Insects of the World
103 flashcards by MentisLibrary
Insect anatomy and life cycles, then the major orders one at a time, with the field marks that separate lookalikes, where each group lives and the part it plays in an ecosystem.
- What three body regions does every adult insect have?
- Head, thorax and abdomen.
- An animal in your hand has eight legs and no antennae. Is it an insect?
- No. Insects have six legs and one pair of antennae; eight legs with no antennae means an arachnid, such as a spider, tick or harvestman.
- What is complete metamorphosis?
- A life cycle of egg, larva, pupa and adult in which the larva looks nothing like the adult and rebuilds its body inside the pupa.
- What is incomplete metamorphosis?
- Egg, a series of nymphs, then adult, with no pupal stage. The nymph resembles a small wingless adult and the wings grow externally with each moult.
- What is an instar?
- The stage between two moults. A rigid cuticle cannot stretch, so an insect grows in steps, shedding the old exoskeleton each time.
- What are ocelli, and how do they differ from compound eyes?
- Ocelli are simple single lens eyes, usually three on top of the head, that measure light level and horizon position. Compound eyes are built of many units and form a coarse mosaic image tuned to movement.
- How does an insect breathe?
- Air enters paired openings called spiracles and travels through a branching network of tracheae directly to the tissues. No blood is involved in gas transport.
- Why is insect blood usually not red?
- Because haemolymph does not carry oxygen. It moves nutrients, hormones and immune cells, so it needs no haemoglobin and is typically clear, yellowish or green.
- What are an insect's antennae mainly for?
- Smell, above all, plus touch, humidity and temperature, and in some groups hearing.
- Which insect order has only one pair of wings, and what happened to the other pair?
- The flies, Diptera. The hind wings are reduced to small club shaped halteres that vibrate and act as gyroscopes.
- What are elytra?
- The hardened front wings of a beetle. They meet in a straight line down the back and cover the folded membranous flight wings.
- What is a hemelytron?
- A front wing that is leathery at the base and membranous at the tip. The overlapping tips form the X pattern on the back of a true bug.
- Nymph or larva: which is which?
- A nymph is the young of an insect with incomplete metamorphosis and looks like a small adult. A larva is the young of an insect with complete metamorphosis and does not.
- What is diapause?
- A hormonally controlled pause in development that carries an insect through a hostile season.
- Name the four main insect mouthpart types and an insect that has each.
- Chewing mandibles in a grasshopper, piercing and sucking stylets in a mosquito or aphid, a coiled siphoning proboscis in a butterfly, and sponging pads in a house fly.
- Roughly how many insect species have been described?
- About one million, more than for all other animal groups combined, and estimates of the true total run to several million.
- Which insect order contains the most described species?
- Beetles, order Coleoptera, with roughly 400,000 described species.
- Which small domed beetle is red or orange with black spots and eats aphids?
- A ladybird, also called a lady beetle, family Coccinellidae.
- Which beetle produces cold light from its abdomen to attract a mate?
- A firefly, family Lampyridae, which is a beetle and not a fly.
- Which large beetle has enormous branched mandibles used by males to wrestle rivals?
- A stag beetle, family Lucanidae.
- Which beetles roll balls of dung and bury them?
- Dung beetles, subfamily Scarabaeinae within the Scarabaeidae.
- Which beetle family is recognised by a long snout with jaws at the tip?
- The weevils, family Curculionidae, one of the largest families in the animal kingdom.
- Which fast running, mostly nocturnal beetles hunt on the soil surface and hide under stones by day?
- Ground beetles, family Carabidae.
- Which beetle snaps its body with an audible click to flip itself upright?
- A click beetle, family Elateridae.
- Which beetles are among the fastest runners on Earth for their size and have long sickle jaws?
- Tiger beetles, subfamily Cicindelinae.
- Which metallic green and copper beetle with white tufts along its sides skeletonises garden leaves in summer?
- The Japanese beetle, Popillia japonica.
- Which yellow and black striped beetle became the textbook case of pesticide resistance?
- The Colorado potato beetle, Leptinotarsa decemlineata.
- Which metallic green wood borer has killed ash trees across large parts of North America?
- The emerald ash borer, Agrilus planipennis.
- Which beetle family has antennae as long as or longer than the body?
- The longhorn beetles, family Cerambycidae.
- Which beetle sprays a boiling chemical defence from the tip of its abdomen?
- The bombardier beetle, several genera in the Carabidae.