Coccinella transversoguttata finds mates through the release of pheromones. Sight is likely also used to identify mates and other individuals. Prey detection is generally accomplished via sight or olfaction. Chemoreception is also used by both adults and juvenile individuals for finding prey. Adults tend to use their antennae as sensory instruments, like many insects. For larvae, touch is another important way to find prey, which they often accomplish using prolegs and the head/mouthparts.
Communication Channels: visual ; chemical
Other Communication Modes: pheromones
Perception Channels: visual ; tactile ; chemical
Coccinella transversoguttata has no special conservation status. However, due to the introduction of various Asian lady beetle species, the population of C. transversoguttata has declined rapidly; if this continues, conservation will likely be necessary.
US Federal List: no special status
CITES: no special status
State of Michigan List: no special status
Coccinella transversoguttata is a holometabolous species. Eggs are laid in early spring, when average temperatures reach 12°C. C. transversoguttata develops through four larval instars, pupates, and then emerges as an adult. Adults diapause over winter and then come out in early spring to mate and oviposit. There is no information regarding the length of time it takes to develop from egg to adulthood. Development and growth of C. transversoguttata is highly effected by prey availability, as well as temperature.
Development - Life Cycle: metamorphosis ; diapause
There are no known adverse affects of Coccinella transversoguttata on humans.
Coccinella transversoguttata is a noted predator in agricultural fields. Because they often prey on agricultural pest species, particularly aphids, they have benefit to the agriculture industry as a biological control agent.
Positive Impacts: controls pest population
Coccinella transversoguttata is historically a notable predator in its native range, as it mainly feeds on aphids that consume various plant species. It has the potential to control the size of an aphid population. This role is becoming diminished as invasive species, such as Harmonia axyridis and Coccinella septempunctata out-compete this species for resources. Harmonia axyridis and Coccinella septempunctata have also been known to prey on all life stages of C. transversoguttata. C. transversoguttata also plays host to several different parasites. Ectoparasitic fungi and ectoparasitic mites have been found on Coccinellids throughout the world. Mites of the genus Coccipolipus have also been found on the species. Male-killing bacterial agents including Rickettsia, Spiroplasma, Wolbachia, Flavobacteria, and γ-proteobacterium have been found on Coccinellidae species. The braconid wasp Dinocampus coccinellae is a major parasitoid on C. transversoguttata. The Tachinidae fly Strongygaster triangulifer may also be a parasitoid of this species.
Commensal/Parasitic Species:
Coccinella transversoguttata feeds almost entirely on aphids and will occasionally feed on scale insects.
Animal Foods: insects
Primary Diet: carnivore (Insectivore )
Coccinella transversoguttata is native to North America, with populations in western Canada, western United States, and into Mexico. They can now also be found in Europe, Asia (excluding China), and Central America. Historically, Coccinella transversoguttata covered much of the eastern United States and Canada, but invasive Coccinellidae species have significantly depleted populations.
Biogeographic Regions: nearctic (Native ); palearctic (Introduced ); oriental (Introduced ); neotropical (Introduced )
Coccinella transversoguttata lives in open areas, such as old fields, agricultural fields, meadows, and marshes, where it feeds on pest herbivores. It is often found on woody plants, crops, and other flowering plants.
Habitat Regions: temperate ; terrestrial
Terrestrial Biomes: savanna or grassland
Wetlands: marsh
Other Habitat Features: suburban ; agricultural
No studies have been conducted regarding the lifespans of Coccinella transversoguttata specifically, but like most Coccinelidae species, this species is a bivoltine organism, with two generations per year that may overlap slightly. In most cases, individuals will live only one season. The last generation will diapause over the winter.
Typical lifespan
Status: wild: 30 to 90 days.
Coccinella transversoguttata is a medium-sized, round, slightly oval beetle, measuring 5 to 7.8 mm in length. It has a red or orange body and black markings. The markings on the elytra include a solid black band behind the pronotum with two elongated black markings nearer the end of the body on each side of the elytra. The pronotum is black with white markings on either side. The head is generally black with two white spots. Antennae are quite short and have a loose club of approximately 3 to 6 segments.
Eggs are small (approximately 1.0 mm) and generally yellow.
The larval form of Coccinella transversoguttata is black and elongate, with many segments. There are several orange spots on the dorsal-lateral area of the abdomen. There are small spines (scoli) running down the length of the body.
Range length: 5 to 7.8 mm.
Other Physical Features: ectothermic ; heterothermic ; bilateral symmetry ; poisonous
Sexual Dimorphism: sexes alike
Invasive Coccinellidae species, such as Harmonia axyridis and Coccinella septempunctata, are often predators of C. transversoguttata, especially during immature stages. To defend itself, C. transversoguttata can reflex bleed when agitated, releasing toxic chemicals from its tarsi that deter predation. Their red or orange coloration functions as an aposematic mechanism against predation.
Known Predators:
Anti-predator Adaptations: aposematic
Coccinella transversoguttata often secretes pheromones to attract mates and at close distances may use sight. Reproduction is sexual, with internal fertilization. This species is polygyandrous; both males and females will readily mate with many individuals. After mating, males do not exhibit any apparent defense mechanisms to ensure the female's eggs are fertilized.
Mating System: polygynandrous (promiscuous)
Coccinella transversoguttata has no apparent reproductive behaviors that differ from other general Coccinellidae species. Eggs are laid in egg masses, which normally contain approximately 20 to 30 eggs. C. transversoguttata will usually lay multiple egg masses per season, sometimes laying upwards of 1000 eggs. It will often lay the egg masses near aphid populations so that the larvae can feed once they emerge. This species breeds consistently throughout the spring and summer. There are typically two generations of C. transversoguttata each year.
Breeding interval: Coccinella transversoguttata can breed continuously throughout the spring and summer months.
Breeding season: After temperatures exceed 12°C, this species can mate indeterminately until temperatures cool again in autumn.
Range eggs per season: 20 to 1000+.
Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; fertilization (Internal ); oviparous
Most coccinellids do not engage in parental care beyond the female providing nutrients within the eggs, which is likely true with this species. Additionally, C. transversoguttata will lay egg masses near aphid populations, providing the larvae with a food source once they hatch.
Parental Investment: pre-hatching/birth (Provisioning: Female)
Coccinella transversoguttata, the transverse ladybird, is a species of ladybird beetle occurring across Europe and North America. It is not to be confused with another species by the same common name, Coccinella transversalis, a widespread species across Australia and Asia.
Coccinella transversoguttata, the transverse ladybird, is a species of ladybird beetle occurring across Europe and North America. It is not to be confused with another species by the same common name, Coccinella transversalis, a widespread species across Australia and Asia.