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Section 1b: Identification of Monarch Pupae, Adults, Host Plants, and Nectar Plants

Monarch Adult Nectaring

This is the third video of the Monarch Larva Monitoring Project video training series, reviewing monarch biology, pupation, eclosion, and male/female identification. An overview of milkweed and nectaring is also provided.

Next Video in Training Series > Section 2: Migration and Overwintering

Glossary of Terms

  • androconial scales
    an-dro-KO-nee-al): wing or body scales that disperse a pheromone.
  • Asclepias syriaca
    (u-SKLEE-pee-us sir-I-uh-kuh): common milkweed. The most common host plant for monarch larvae in the upper Midwestern U.S. Monarchs also eat other members of the genus Asclepias.
  • camouflage
    to hide or disguise. There are two types of camouflage: protective resemblance and protective coloration. Protective resemblance is when something looks like something else in its environment. Protective coloration is when something has the same color or pattern as its surroundings.
  • chorion
    KOR-ee-ahn): the hard outer shell of insect eggs. (In general, the chorion is the outermost membrane enclosing the developing embryo. In reptiles, this layer lies just inside the shell, and in mammals the chorion becomes the placenta.)
  • cuticle
    the hard outside part of the butterfly's skin that is no longer living.
  • eclose
    to emerge as an adult from the pupa stage.
  • family
    a category of classification that contains related genera.
  • genus (plural, genera)
    a category in a classification that contains one to many similar or related species.
  • hemolymph
    (HEE-muh-lim(p)f): the name for the blood of insects.
  • instar
    a period between larval molts. There are five of these periods in the growth of a monarch larva.
  • larva
    (LAR-vuh), plural, larvae (LAR-vee): the second stage, after the egg, in metamorphosis. Also known as a caterpillar. Monarchs molt five times in their larval stage, which lasts about 9-14 days.
  • Lepidoptera
    (lep-uh-DOP-ter-uh): the order of insects that is made up of butterflies and moths. This word should be capitalized, but the adjective lepidopteran should not.
  • meconium
    (mi-KO-nee-um): the fluid monarchs excrete shortly after they emerge from the chrysalis.
  • metamorphosis
    (met-uh-MOR-fuh-sis): the series of developmental stages through which insects go to become adults. Through metamorphosis a butterfly is transformed from an egg, to a larva, to a pupa, to a butterfly. There are two types of metamorphosis: incomplete (simple) and complete (complex) metamorphosis. The four distinct stages of metamorphosis found in butterflies is considered complete metamorphosis. Incomplete metamorphosis does not have a prolonged immobile (pupa) stage.
  • molt
    the process of shedding the skin or exoskeleton. Monarch larvae molt five times.
  • order
    a category in classification that contains related families.
  • pheromones
    (FAIR-uh-mohns): special chemicals released by some animals to communicate with other members of their species. They may be sensed over long distances to help mates find each other. They may also help ensure that mating only occurs with other members of the same species.
  • pigmentation
    coloration caused by all light wavelengths, but that of the color emitted, being absorbed.
  • proboscis
    (pro-BAHS-kiss): the adult monarch's feeding tube, for sucking nectar, which is coiled under the head when not in use.
  • prolegs
    the "false" legs on the abdominal segments of the monarch larva.
  • pupa
    (PU-puh) plural, pupae (PU-pee): the third stage in metamorphosis, after the larval stage. In monarchs this stage lasts 8-13 days.
  • pupate
    to change from a larva (caterpillar) to a pupa (chrysalis).
  • scales
    overlapping pieces of chitin (the same material of which exoskeletons are made) that insulate butterflies' bodies and wings, improve their aerodynamics, and give them color and markings. Many people think the scales look like fine dust on butterfly wings.
  • species
    a group of organisms recognized as distinct from other groups. Differentiates between members of a genus.
  • tactile setae
    TAK-tile SEE-tay): hairs through which butterflies and moths sense touch. They extend through the exoskeleton and connect to nerve cells inside the insect's body.
  • tentacles
    the fleshy black extensions at the front and rear of the monarch larvae, which function as sense organs. Also called filaments.
  • thorax
    the middle section of an insect's body. The wings (if present) and legs are attached to this segment.
  • true legs
    jointed appendages located on the thoracic segment of the larva. Contrast with prolegs.

Photo Credits (in order of appearance)

1. Monitoring site with milkweed: Deb Marcinski
2. Monarch pupa on peony leaf: Robert B. Hughes
3. Cocoon: Flickr photographer Dean Morley (deanster1983)
3. J and pupa in peony bush: Robert B. Hughes
4. 5th instar crawling on tree: Kelly Duhn
5. Series of transformation from larva to pupa:
6. Monarch egg close-up: Monarch Lab Photo
7. 5th instar eating: Denny Brooks
8. Adult male monarch on purple flower: Dave Astin
9. Common milkweed: Wendy Caldwell
10. Wing pigmentation on pupa: Siah St. Clair
11. Series of adult eclosion:
12. Female and male comparison: Michelle Solensky
13. Female abdomen: Bruce & Tamy Leventhal
14. Male abdomen: Bruce & Tamy Leventhal
15. Mating adults resting on a branch: Wendy Caldwell
16. Asclepias incarnata, or swamp milkweed: Wendy Caldwell
17. Asclepias tuberosa, or butterfly milkweed: Wendy Caldwell
18. Asclepias syrica, or common milkweed: Monarch Watch
19. Asclepias asperula, antelopehorns milkweed: Carol Cullar
20. Asclepias verticillata, or whorled milkweed: Karen Oberhauser
21. Butterflies on New England aster: Jim Ellis
22. Monarch on Rudbeckia: Barbara Powers
23. Butterflies on goldenrod: Jim Ellis
24. Adult monarch nectaring close-up: Jim Ellis
25. Monarchs nectaring preparing for migration: Dallas Hudson