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Common Buckeye

Junonia coenia

Summary 7

The common buckeye or simply, buckeye, (Junonia coenia) is a butterfly in the family Nymphalidae. It is found in southern Manitoba, Ontario, Quebec, and Nova Scotia and all parts of the United States except the northwest, and is especially common in the south, the California coast, and throughout Central America and Colombia. The sub-species Junonia coenia bergi is endemic to the island of Bermuda.

Physical description 8

The eggs of Junonia coenia are a dark green.

The larva that hatch from the eggs are nearly black and have two rows of orange-cream spots along the middorsal. There are two lateral rows of cream spots and the larva has many bluish-black spines. The prolegs are orange. The head is black with an orange spot toward the anterior and two short black spines on top, and orange on the top and sides.

Pupa color varies from light color with brownish-orange blotches, to entirely brownish-orange, to nearly black.

The adult stage of the butterfly has brown wings with three eyespots per wing, one on the upper and two on the hindwing. There are characteristic orange bands on the forewing. They have a particularly large eyespot on the hindwing that is reddish to purple. Adult coloration varies, with a form called "rosa," (with red under-hindwings) that appears late in the fall in eastern U.S., and may be a result of short daylength or lower temperatures.

Range wingspan: 4 to 6 cm.

Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry ; polymorphic

Habitat 9

Junonia coenia tends to like more open areas such as fields, parks, pastures, meadows, and coastal dunes. You can also find them along roadsides and in other disturbed, weedy places. They are often near their food plants, and may also feed or drink around mud puddles.

Habitat Regions: temperate ; tropical ; terrestrial

Terrestrial Biomes: desert or dune ; chaparral ; scrub forest

Other Habitat Features: urban ; suburban ; agricultural

Food habits 10

Adults feed mainly on nectar, and occasionally on mud from the edge of puddles (probably for salts and other minerals).

Caterpillars feed on a wide variety of host plants, nearly all herbaceous (see partial list below). Females may be stimulated to oviposit by the presence of iridoid glycosides (Kluts, 1951, Scott, 1986).

Foods eaten: plantains (Plantago), gerardia, toadflax (Linaria), wild snapdragons (Antirrhinum),  false loosestrife (Ludvigia), stonecrop (Sedum).

Plant Foods: leaves; nectar

Primary Diet: herbivore (Folivore , Nectarivore )

Reproduction 11

Males perch on the ground or low plants and watch for passing females. They pursue any likely object. Females inclined to mate will land, and the male will follow. Courtship behavior is variable. Sometimes they land, fold their wings, and mate. On other occasions females have been observed fluttering their wings after landing. The male responds by hovering over her and fluttering his wings as he lands behind her. The male will then pursue her by nudging her from behind. They will then mate, or if she chooses not to mate, she will flap her wings with a high intensity, spread her wings and lift her abdomen to deny him access, or just fly away.

Mating System: polygynous

After mating, female buckeyes lay their eggs on the leaves of host plants that their larvae will eat. In the northern part of the range there may only be one or two generations a year, and it's unlikely that adults can survive the winter. Further south (Florida, Texas, California and beyond), there are adults flying nearly all year.

Breeding season: Year-round in southern range, narrowing to summer in the north.

Key Reproductive Features: semelparous ; seasonal breeding ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); oviparous

There is no parental care in this species.

Parental Investment: no parental involvement

Development 12

Female buckeyes lay eggs individually on buds and leaves of host plants. The larvae (caterpillars) emerge and feed and grow on the host plant, molting several times. Larvae transform into pupae, and spend the winter in this stage in the northern part of the range. Metamorphosis is completed in the pupal case, and fully developed adult butterflies emerge. They can take flight after their wings dry. In the southern half of the range, this species may develop and reproduce continually with no diapause or winter dormancy.

Development - Life Cycle: metamorphosis ; diapause

Sources and Credits

  1. (c) Bill Bumgarner, some rights reserved (CC BY-NC-ND), http://www.flickr.com/photos/49503114554@N01/1581649444
  2. (c) Smithsonian National Museum of Natural History, some rights reserved (CC BY-NC), http://www.flickr.com/photos/nmnh/6838087615/
  3. (c) Greg Lasley, some rights reserved (CC BY-NC), uploaded by Greg Lasley
  4. (c) Stephen Durrenberger, some rights reserved (CC BY-NC-SA), http://www.flickr.com/photos/38275458@N05/6242773374
  5. (c) Matthew High, some rights reserved (CC BY-NC), http://www.flickr.com/photos/16268809@N04/5061345058
  6. (c) Mary Keim, some rights reserved (CC BY-NC-SA), http://farm7.static.flickr.com/6228/6319347070_c6b7c36c2b_o.jpg
  7. (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Junonia_coenia
  8. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18652781
  9. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18652780
  10. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18652785
  11. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18652783
  12. (c) The Regents of the University of Michigan and its licensors, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/18652782

More Info

iNat Map

Taxonomy:family Nymphalidae
Color brown, orange
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