Coccinella novemnotata

Geographic Range

Coccinella novemnotata, the nine-spotted lady beetle, was historically one of the most prevalent ladybird beetle species in its range. It was found throughout the Nearctic region in the United States and southern Canada. However, its range has significantly diminished in recent years, particularly in the United States. A survey in 2009 found only a few specimens in western and central United States. Another survey conducted by the USDA Animal and Plant Health Inspection Service in 1993 found no Coccinella novemnotata in thirteen Northeastern states, though a single specimen was found in 2006 in Virginia, the first to be spotted in 14 years in the eastern states. (Gordon, 1985; Harmon, et al., 2007; Hesler, et al., 2009)

Habitat

Coccinella novemnotata is found on agricultural land and lives on various crops such as alfalfa, clover, corn, cotton, potatoes and soybeans. These beetles can also be found on a variety of non-agricultural vegetation in wooded habitats, grasslands and suburban areas. A survey conducted found that C. novemnotata is highly likely to be living in national parks, though the reason for this is unknown. (Gordon, 1985; Harmon, et al., 2007; Hesler, et al., 2009)

Physical Description

Coccinella novemnotata typically has nine spots, which gives it its name (novem- nine in Latin), although there are spotless forms which may be confused with Coccinella johnsi. They are red, oval-shaped and range from 4.7 to 7.0 mm. They range in size (area of their elytra) from 24.36 to 37.66 sq. mm. Coccinella novemnotata has a broad head with a pale band between its eyes that is posteriorly and anteriorly black. The anterior margin of the pronotum is pale as well. There is a large ventral pale spot that is trapezoidal, extending posteriorly as far as the dorsal spot. The elytra have black spots that get smaller in size and in number until the scutellar spot.

Coccinella novemnotata eggs are usually orange to bright yellow in color. Eggs that are viable retain this color while non-viable eggs shrivel and become dark brown or black within 2 to 3 days. (Gordon, 1985; Losey, et al., 2012)

  • Sexual Dimorphism
  • sexes alike
  • Range length
    4.7 to 7.0 mm
    0.19 to 0.28 in

Development

Larvae of Coccinella novemnotata hatch from eggs after approximately four days. The larvae undergo four instars before pupating, metamorphosing, and reaching adulthood. It takes an average of four to five days for Coccinella novemnotata to reach its third-instar. After approximately seven more days, the larvae spend one day in a pre-pupal stage where they stop eating and appear very sluggish. The larvae then pupate. After four days, adults emerge. After one day, the elytra on the adult Coccinella novemnotata hardens. (Losey, et al., 2012)

Reproduction

There is not available literature that describes the mating systems of Coccinella novemnotata, but there is research that describes the mating systems of the very similar Coccinella septempunctata. Males of Coccinella septempunctata exhibit a five step courtship display. They first approach a female, watch, then examine, mount and attempt copulation. Females who are not sexually mature, have recently mated, or are about to oviposit, exhibit a display of rejection towards the male. Males recognize female mates based on chemical and visual cues, such as size and female body shape. It is possible that the chemical cues play a larger role in attracting a male than the visual cues. Males may mate multiple times in one day. It is possible, though not certain, that the mating habits of C. novemnotata are similar to those of C. septempunctata. (Omkar and Srivastava, 2002; Srivastava and Omkar, 2004)

There is little available scientific literature that describes the general mating behavior of Coccinella novemnotata. It is known that C. novemnotata reaches sexual maturity 2 to 4 days after it becomes an adult. Adults breed continuously during a several week period in the summer that occurs before overwintering. (Losey, et al., 2012)

  • Breeding interval
    Adults breed continuously, living for several weeks.
  • Breeding season
    Adults breed for several weeks in the summer.
  • Range age at sexual or reproductive maturity (female)
    22 to 25 days
  • Range age at sexual or reproductive maturity (male)
    22 to 25 days

Literature is not available that describes the parental investment of Coccinella novemnotata, but typically Coccinellidae provide only nutrients in the egg and no other parental investment. (Gordon, 1985)

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

Lifespan/Longevity

There is little information available on this topic for C. novemnotata, though it is known that it takes approximately 20 days for C. novemnotata to develop from an egg to an adult. Adults then live for several weeks during the summer, with the final generation overwintering. (Losey, et al., 2012)

Behavior

Coccinella novemnotata is a predator of many species of aphids. It is a mobile insect that actively hunts its prey. Coccinella novemnotata crawls or flies. It is mainly active during the day. There is little known about the social behavior of Coccinella novemnotata, most likely because it is so scarcely found in North America today. (Gordon, 1985)

Communication and Perception

There is no available information that describes the communication and perception of Coccinella novemnotata, but it is likely similar to other Coccinellidae that rely on mainly visual and chemical inputs to locate prey and mates. (Omkar and Srivastava, 2002; Srivastava and Omkar, 2004)

Food Habits

Coccinella novemnotata is an insectivore coccinellid and thrives primarily on a diet of aphids. They prey on a large variety of aphids, including pea aphids, green peach aphids, and cheery-oat aphids. They will also eat spider mites, alfalfa weevils, the nymphs of leafhoppers, and lepidopteran eggs. (Hesler, et al., 2012; Losey, et al., 2012; Wheeler and Hoebeke, 1995)

  • Animal Foods
  • insects

Predation

Like most Coccinellidae, C. novemnotata is subject to interspecies predation and cannibalism. Coccinella transversoguttata is known to prey on all life stages of C. novemnotata. In lab reared populations, it has been observed that active stages of C. novemnotata will cannibalize eggs and pupae, while large larvae will prey on smaller larvae. As a coccinellid, it is likely that C. novemnotata can reflex bleed when threatened by a predator, excreting a toxin from its joints. The red color of these beetles functions as aposematic warning coloration. (Gordon, 1985; Hesler, et al., 2012; Losey, et al., 2012)

Ecosystem Roles

Coccinella novemnotata acts as a predator to many species of aphids, as well as spider mites, alfalfa weevils, leafhopper nymphs, and lepidopteran eggs. Aphids are the primary prey of both larvae and adults of C. novemnotata. Competition over aphid prey and other food is suspected to have led to the diminished population of C. novemnotata in North America today. Evidence suggests that C. novemnotata is competing with the introduced species, Coccinella septempunctata, for aphids. The body size of C. novemnotata is particularly susceptible to prey availability, and the mean body size has decreased significantly in the past few years, indicating that C. novemnotata is being out-competed for prey. Other factors that have been proposed as reasons for the decline of Coccinella novemnotata are climate change as well as a change in agricultural land use. Other invasive species, such as Harmonia axyridis have not been attributed with the decline of this species. Coccinella novemnotata is also considered to be a natural enemy of Ostrina nubilalis, the European corn borer. The braconid wasp Perilitus coccinellae is known to be a parasite of C. novemnotata adults. (Losey, et al., 2012; Wheeler and Hoebeke, 1995)

Coccinella novemnotata eats many species of aphids, as well as spider mites, alfalfa weevils, leafhopper nymphs, and butterfly and moths eggs. The population of C. novemnotata has decreased recently in North America. This is thought to be caused by competition for food (aphids) between C. novemnotata and other species, such as Coccinella septempunctata. Coccinella septempunctata is an invasive species, and is likely pushing C. novemnotata out of its habitat. The body size of C. novemnotata is effected by the amount of food available. In the past few years, the average body size of C. novemnotata has decreased, which shows that individuals of C. novemnotata are not getting enough food. The population of C. novemnotata may also have decreased because of climate change, as well as changes in farm land (their food, aphids, are usually very common on crops on farmland). Coccinella novemnotata is considered to be a natural enemy of Ostrina nubilalis, the European corn borer. The wasp Perilitus coccinellae is known to be a parasite of C. novemnotata adults. (Losey, et al., 2012; Wheeler and Hoebeke, 1995)

Commensal/Parasitic Species
  • Perilitus coccinellae

Economic Importance for Humans: Positive

In 1914 in Connecticut and 1930 in Minnesota, Coccinella novemnotata was ranked as one of the coccinellids with the greatest economic importance, as it could control aphid populations on crops. However, since that time the decline of the species has reduced its importance. (Britton, 1914; Stehr, 1930)

  • Positive Impacts
  • controls pest population

Economic Importance for Humans: Negative

There are no known adverse affects of Coccinella novemnotata on humans.

Conservation Status

This species currently has no conservation status, but due to the massive decline in population size across the United States, C. novemnotata is a likely candidate for future conservation efforts. (Harmon, et al., 2007)

Other Comments

In 2000, Cornell University started The Lost Ladybug Project, which uses images of ladybugs taken by citizens to identify coccinellids from across the country. This project has been effective in providing information about the location of coccinellids, and has helped establish the limited presence of C. novemnotata in the western states. ("The Lost Ladybug Project", 2013; Losey, et al., 2012)

Contributors

Deeana Ijaz (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

agricultural

living in landscapes dominated by human agriculture.

aposematic

having coloration that serves a protective function for the animal, usually used to refer to animals with colors that warn predators of their toxicity. For example: animals with bright red or yellow coloration are often toxic or distasteful.

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.

carnivore

an animal that mainly eats meat

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.

diurnal
  1. active during the day, 2. lasting for one day.
ectothermic

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

fertilization

union of egg and spermatozoan

forest

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

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.

insectivore

An animal that eats mainly insects or spiders.

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.

poisonous

an animal which has a substance capable of killing, injuring, or impairing other animals through its chemical action (for example, the skin of poison dart frogs).

polygynandrous

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

polymorphic

"many forms." A species is polymorphic if its individuals can be divided into two or more easily recognized groups, based on structure, color, or other similar characteristics. The term only applies when the distinct groups can be found in the same area; graded or clinal variation throughout the range of a species (e.g. a north-to-south decrease in size) is not polymorphism. Polymorphic characteristics may be inherited because the differences have a genetic basis, or they may be the result of environmental influences. We do not consider sexual differences (i.e. sexual dimorphism), seasonal changes (e.g. change in fur color), or age-related changes to be polymorphic. Polymorphism in a local population can be an adaptation to prevent density-dependent predation, where predators preferentially prey on the most common morph.

seasonal breeding

breeding is confined to a particular season

sexual

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

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.

tropical savanna and grassland

A terrestrial biome. Savannas are grasslands with scattered individual trees that do not form a closed canopy. Extensive savannas are found in parts of subtropical and tropical Africa and South America, and in Australia.

savanna

A grassland with scattered trees or scattered clumps of trees, a type of community intermediate between grassland and forest. See also Tropical savanna and grassland biome.

temperate grassland

A terrestrial biome found in temperate latitudes (>23.5° N or S latitude). Vegetation is made up mostly of grasses, the height and species diversity of which depend largely on the amount of moisture available. Fire and grazing are important in the long-term maintenance of grasslands.

visual

uses sight to communicate

References

2013. "The Lost Ladybug Project" (On-line). Accessed March 27, 2013 at http://www.lostladybug.org/.

Britton, W. 1914. Some common lady beetles of Connecticut. Connecticut Agricultural Experiment Station Bulletin, 181: 1-24.

Gagne, W., J. Martin. 1968. The insect ecology of red pine plantations in Central Ontario V. The Coccinellidae (Coleoptera). Canadian Entomologist, 100: 835-846.

Gordon, R. 1985. The Coccinellidae (Coleoptera) of America north of Mexico. Journal of the New York Entomological Society, 93: 1-912.

Harmon, J., E. Stephens, J. Losey. 2007. The decline of native coccinellids (Coleoptera: Coccinellidae) in the United States and Canada. Journal of Insect Conservation, 11: 85-94.

Hesler, L., M. Catangui, J. Losey, J. Helbig, A. Mesman. 2009. Recent Records of Adalia bipunctata (L.), Coccinella transversoguttata richardsoni Brown, and Coccinella novemnotata Herbst (Coleoptera: Coccinellidae) from South Dakota and Nebraska. The Coleopterists Bulletin, 64/4: 475-484.

Hesler, L., G. McNickle, M. Catangui, J. Losey, E. Beckendorf, L. Stellwag, D. Brandt, P. Bartlett. 2012. Method for Continuously Rearing Coccinella Lady Beetles (Coleoptera: Coccinellidae). The Open Entomology Journal, 6: 42-48.

Hudon, M. 1959. First Record of Perilitus coccinellae (Schrank) (Hymenoptera: Braconidae) as a Parasite of Coccinella novemnotata Hbst. and Coleomegilla maculata lengi Timb. (Coleoptera: Coccinellidae) in Canada. The Canadian Entomologist, 91/1: 63-64.

Losey, J., J. Perlman, E. Hoebeke. 2007. Citizen scientist rediscovers rare nine-spotted lady beetle, Coccinella novemnotata, in eastern North America. Journal of Insect Conservation, 11/4: 415-417.

Losey, J., J. Perlman, J. Kopco, S. Ramsey, L. Hesler, E. Evans, L. Allee, R. Smyth. 2012. Potential causes and consequences of decreased body size in field populations of Coccinella novemnotata. Biological Control, 61: 98-103.

Omkar, , S. Srivastava. 2002. The reproductive behaviour of an aphidophagous ladybeetle, Coccinella septempunctata (Coleoptera: Coccinellidae). European Journal of Entomology, 99: 465-470.

Srivastava, S., Omkar. 2004. Age-specific mating and reproductive senescence in the seven-spotted ladybird, Coccinella septempunctata. Journal of Applied Entomology, 128: 452-458.

Stehr, W. 1930. The Coccinellidae (ladybird beetles) of Minnesota. University of Minnesota Agricultural Experiment Station Technical Bulletin, 75: 1-54.

Wheeler, A., E. Hoebeke. 1995. Coccinella novemnotata in Northeastern North America: historical occurrence and current status (Coleoptera: Coccinellidae). Proceeding of the Entomological Society of Washington, 97: 701-716.