Insect Biology & Identification Flashcards

Which insect order is characterized by having scales on the wings and a coiled proboscis for feeding?

Answer: Lepidoptera

Lepidoptera (moths and butterflies) are uniquely characterized by scales covering their wings and a coiled, sucking proboscis called a haustellum.

What type of metamorphosis involves egg, nymph, and adult stages with no pupal stage?

Answer: Hemimetabolous

Hemimetabolous (incomplete metamorphosis) insects pass through egg, nymph, and adult stages, with nymphs gradually resembling adults.

The spiracles of insects are primarily used for:

Answer: Gas exchange during respiration

Spiracles are external openings of the tracheal system that allow oxygen intake and carbon dioxide expulsion in insects.

Which of the following correctly describes the difference between mandibulate and haustellate mouthparts?

Answer: Mandibulate mouthparts chew solid food; haustellate mouthparts pierce and suck liquid

Mandibulate insects use hardened mandibles to bite and chew solid food, while haustellate insects use modified mouthparts to pierce tissue and suck liquid.

In insect taxonomy, which term refers to the protective wing covers in beetles (Coleoptera)?

Answer: Elytra

Elytra are the hardened, sclerotized forewings of beetles that protect the membranous hindwings used for flight.

The tarsal formula 5-5-4 in a beetle specimen indicates:

Answer: Five tarsomeres on the front leg, five on the mid leg, four on the hind leg

Tarsal formula describes the number of tarsomeres (tarsal segments) on the front, middle, and hind legs respectively, an important identification character in beetles.

Which insect structure is homologous to the wings and is used for balance in flies (Diptera)?

Answer: Halteres

Halteres are modified hindwings in Diptera that function as gyroscopic balance organs during flight.