Calligrapha philadelphica

Geographic Range

Calligrapha philadelphica can be found in the eastern half of North America, in the Nearctic region. In Canada, specimens have occasionally been spotted as far west as British Columbia. (Robertson, 1966)

Habitat

Calligrapha philadelphica is found on dogwood plants in temperate forests. In areas where there is an abundance of dogwood, C. philadelphica can be found forming small colonies. This chrysomelid beetle has also been found on willow plants in areas where dogwood and willow are present together. (Robertson, 1966)

Physical Description

All Calligrapha share common features such as an oval, rounded form, an unjointed terminal tarsal joint without teeth underneath, and divergent claws. Calligrapha philadelphica has white elytra with dark markings arranged in a pattern of longer lines, smaller curving lines, and dots which are described in its Latin name meaning "beautiful + writing." C. philadelphica is usually 8 to 9 mm in length. It has elytra with a thin subsutural line. The body of this beetle is robust, convex, and shiny. The aedeagus of the male C. philadelphica has lateral apical spiculi and does not have an apical truncate projection. Egg coloration of C. philadelphica varies from creamy white to coral. (Arnett, 1960; Blatchley, 1910; Jaques, 1971)

  • Sexual Dimorphism
  • sexes alike
  • Range length
    8 to 9 mm
    0.31 to 0.35 in

Development

Adults hibernate during the winter in the ground or sheltered within the bark of trees. Upon the arrival of spring, mating and oviposition occur during which single or multiple eggs can be laid. Approximately a week after oviposition occurs in May or June, larva emerge, feed quickly, and pupate shortly thereafter in the soil. Adults emerge around early July and feed until late September. They then overwinter until the following spring. (Robertson, 1966)

Reproduction

As a chrysomelid, Calligrapha philadelphica can likely find host plants to feed on due to chemical senses and cues. This suggests that C. philadelphica uses these same chemicals or scents to find mates. Both males and females have been observed to mate with other species, C. rowena and C. vicina. (Robertson, 1966; Mitchell, 1988; Robertson, 1966)

Calligrapha philadelphica utilizes diploid bisexual reproduction. Eggs are laid either singly or in masses of up to 32 eggs. Over the course of a season, a female can lay between 100 and 450 eggs. Most eggs are generally deposited before June. Calligrapha is highly variable in terms of intra and inter-specific sex ratio. In some similar species, female-producing parthenogenesis may occur, indicated by the high ratio of females to males. In past collections of C. philadelphica, females have made up 50% to 100% of the collection, suggesting this species may also be parthenogenic. (Robertson, 1966)

Calligrapha philadelphica is a bisexual diploid. Little study has focused on identifying whether certain species of Calligrapha are sister species. C. philadelphica will mate with other species, C. rowena and C. vicina (which utilizes tetraploid parthenogenesis). A population of C. philadelphica has been known to mate with another population differing only in supernumerary chromosomes. Robertson (1966) finds that there is variation in whether or not the spermatogonial complement of C. philadelphica contained supernumerary chromosomes. Variation of the supernumerary chromosomes within the study ranged from 0 to 10 in Ottawa, Canada, whereas in Quebec the study found that spermatogonial complements contained 22 autosomes, one X chromosome, and an average of seven supernumerary chromosomes. This polymorphism may be an adaptation that helps populations survive and is an indicator of potential speciation. (Robertson, 1966)

  • Breeding interval
    There is a single generation of Calligrapha philadelphica each year.
  • Breeding season
    Oviposition occurs in the middle of May and continues through June.
  • Range eggs per season
    100 to 450

Other than provisioning of eggs, there is no parental involvement in this species.

  • Parental Investment
  • pre-hatching/birth
    • provisioning
      • female

Lifespan/Longevity

It takes approximately 2 to 3 months for C. philadelphica to develop from an egg to an adult. After emerging from pupation, adults continue to feed for another 2 to 3 months until overwintering and emerging again the following spring. (Robertson, 1966)

Behavior

Calligrapha philadelphica will amass in small colonies in areas where there is an abundance of the host dogwood plants. Otherwise it is a solitary species. C. philadelphica can fly, though it does not fly far from the patches of dogwood that it inhabits. (Robertson, 1966)

Home Range

Dogwood, the host plant of Calligrapha philadelphica, has an expansive range in North America and therefore C. philadelphica is also widely dispersed throughout the eastern half of the United States. Individuals stay mainly within a patch of host plant. (Jaques, 1971; Robertson, 1966)

Dogwood, the host plant of Calligrapha philadelphica, has an large range in North America. Since C. philadelphica lives and feeds on dogwood, it is also found throughout the eastern half of the United States. These beetles stay mainly within a patch of dogwood plant. (Jaques, 1971; Robertson, 1966)

Communication and Perception

Calligrapha philadelphica, as a chrysomelid, can most likely recognize host plants via visual acuity and chemical cues. It can perceive both the environment and other members of the species (as well as similar species) visually and chemically. (Mitchell, 1988)

Food Habits

Calligrapha philadelphica feeds on the leaves of dogwood plants, Cornus stolonifera and Cornus obliqua. (Robertson, 1966)

  • Plant Foods
  • leaves

Predation

No information is available on this topic.

Ecosystem Roles

Chrysomelidae, including C. philadelphica are important phytophagous beetles which are host-specific in terrestrial habitats and modify their ecosystems in a host-specific way. C. philadelphica specifically effects the population of dogwood plants, Cornus stolonifera and Cornus obliqua, as the beetles devour the plant leaves. (Robertson, 1966)

Species Used as Host
  • Cornus stolonifera
  • Cornus obliqua

Economic Importance for Humans: Positive

There are no known positive effects of Calligrapha philadelphica on humans.

Economic Importance for Humans: Negative

There are no known adverse affects of Calligrapha philadelphica on humans.

Conservation Status

Calligrapha philadelphica has no special conservation status.

Contributors

Rachael Gingerich (author), University of Michigan Biological Station, Angela Miner (editor), Animal Diversity Web Staff, Brian Scholtens (editor), University of Michigan Biological Station.

Glossary

Nearctic

living in the Nearctic biogeographic province, the northern part of the New World. This includes Greenland, the Canadian Arctic islands, and all of the North American as far south as the highlands of central Mexico.

World Map

bilateral symmetry

having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.

chemical

uses smells or other chemicals to communicate

diapause

a period of time when growth or development is suspended in insects and other invertebrates, it can usually only be ended the appropriate environmental stimulus.

ectothermic

animals which must use heat acquired from the environment and behavioral adaptations to regulate body temperature

fertilization

union of egg and spermatozoan

folivore

an animal that mainly eats leaves.

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

herbivore

An animal that eats mainly plants or parts of plants.

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

hibernation

the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The act or condition of passing winter in a torpid or resting state, typically involving the abandonment of homoiothermy in mammals.

internal fertilization

fertilization takes place within the female's body

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

metamorphosis

A large change in the shape or structure of an animal that happens as the animal grows. In insects, "incomplete metamorphosis" is when young animals are similar to adults and change gradually into the adult form, and "complete metamorphosis" is when there is a profound change between larval and adult forms. Butterflies have complete metamorphosis, grasshoppers have incomplete metamorphosis.

motile

having the capacity to move from one place to another.

native range

the area in which the animal is naturally found, the region in which it is endemic.

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

parthenogenic

development takes place in an unfertilized egg

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

solitary

lives alone

suburban

living in residential areas on the outskirts of large cities or towns.

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

visual

uses sight to communicate

References

Arnett, R. 1960. The beetles of the United States. Washington, D.C.: The Catholic University of America Press.

Blatchley, W. 1910. Catalogue of the Coleoptera of Indiana. Indianapolis, Indiana: WM. B. Burford, Contractor for State Publishing and Printing.

Dickinson, J. 1997. Multiple mating, sperm competition, and cryptic female choice in the leaf beetles. Pp. 164-183 in J Choe, B Crespi, eds. The Evolution of mating systems in insects and arachnids. Cambridge, United Kingdom: The Press Syndicate of the University of Cambridge.

Jaques, H. 1971. How to know the beetles. United States of America: WM. C. Brown Company Publishers.

Mitchell, B. 1988. Adult leaf beetles as models for exploring the chemical basis of host-plant recognition. Insect Physiology, 34: 213-225.

Robertson, J. 1966. The chromosomes of bisexual and parthenogenetic species of Calligrapha (Coleoptera: Chrysomelidae) with notes on sex ratio, abundance and egg number. Canadian Journal of Genetics and Cytology, 8: 695-732.