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.
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.
Communication Channels: visual ; chemical
Perception Channels: visual ; chemical
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.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
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.
Development - Life Cycle: metamorphosis ; diapause
There are no known adverse affects of Coccinella novemnotata on humans.
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 in crops. However, since that time the decline of the species has reduced its importance.
Positive Impacts: controls pest population
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.
Commensal/Parasitic Species:
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.
Animal Foods: insects
Primary Diet: carnivore (Insectivore )
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.
Biogeographic Regions: nearctic (Native )
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 are highly likely to be living in national parks, though the reason for this is unknown.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: savanna or grassland ; forest
Other Habitat Features: suburban ; agricultural
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.
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.
Range length: 4.7 to 7.0 mm.
Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry ; polymorphic ; poisonous
Sexual Dimorphism: sexes alike
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.
Known Predators:
Anti-predator Adaptations: aposematic
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.
Mating System: polygynandrous (promiscuous)
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.
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.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); oviparous
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.
Parental Investment: pre-hatching/birth (Provisioning: Female)
