Unit 13 - Anthropods 3

3 tagamata, head, thorax, abdomen. 3 pairs of legs. none, one or 2 pairs of wings. Legs and wings on thorax only.

3 basic stages are egg, juvenile, adult. Stages are subdivided into stages that are separated by molts.

Instars

Ametabolous, Hemimetabolous, Holometabolous

Imago

Direct development, exhibited by wingless hexapods, juvenile instars identical to adults but are smaller and sexually immature. Imago continues to grow and molt after maturity

Incomplete metamorphosis, juveniles look somewhat different from adults, wing pads develop progressively with each instar. Imago does not grow or molt.

Complete metamorphisis, Juveniles look entirely different from adults, worm like, pupa stage between last juvenile instar and imago.

Entognatha and Insecta

Mouth parts recessed in a deep pocket in the head capsule. No wings.

Collembola (Springtails).

Mouth parts exposed, not recessed in a deep pocket (Ectognathous).

Ectognathous

Thysanura, Odonata, Orthoptera, Hemiptera, Coleoptera, Lepidoptera, Diptera, Hymenoptera.

Wingless, flat, carrot shaped, silverfish and bristletails.

Voracious predators, nymphs have raptorial labia, dragonflies and damselflies.

Enlarged hind legs for jumping, stridulating organs on legs or wings for producing courtship sounds, Herbivourous with chewing mouthparts.

Have piercing and sucking mouthparts, feed on plant juices, true bugs, hoppers, cicadas.

Elytra are thick, hard and opaque. Mouthparts used mostly for chewing plants, detritus, carrion. Beetles.

Wings covered with overlapping scales, long proboscis for sucking nectar. Moths and butterflies.

Caterpillars with prolegs on abdomen.

One pair of wings, hindwings are reduced and called halteres, used for balancing. Mouthparts used for piercing, sucking or sponging. True flies.

Chewing mouthparts modified for sucking, female ovipositor modified into a stinger. Ants, bees, wasps.