Blister Beetles
Meloidae
Classification
- Phylum: Arthropoda
- Subphylum: Hexapoda
- Class: Insecta
- Order: Coleoptera
- Suborder: Polyphaga
- Superfamily: Tenebrionoidea
- Family: Meloidae
Pronunciation
How to pronounce Meloidae: /məˈloɪdiːiː/
These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.
Images
Summary
Blister beetles of the family Meloidae are known for their toxic secretion, cantharidin, which can cause blistering. They are hypermetamorphic insects with a diverse diet consisting mainly of plants and some insect species. Their life cycle includes several stages, starting as mobile larvae that seek hosts.
Physical Characteristics
Typical body length ranges from 3 to 70 mm, often between 10 to 20 mm. Many species exhibit aposematic coloration due to their toxic nature.
Identification Tips
Look for brightly colored or patterned beetles that are often found on flowers. Some species secrete cantharidin as a defensive mechanism, which may cause blisters on contact.
Habitat
Primarily found in arid and semi-arid areas, including the southwestern United States, where they often inhabit flower gardens and areas with blooming plants.
Distribution
Approximately 410 species in 22 genera present in the area, with around 3000 species in 120 genera worldwide.
Diet
Adults feed on leaves and flowers of various plant families, including Asteraceae, Fabaceae, and Solanaceae. Larvae are primarily insectivorous, feeding on bees and grasshopper eggs.
Life Cycle
Blister beetles undergo a hypermetamorphic life cycle with several larval stages, starting with a mobile triungulin that seeks out hosts. The life cycle can take from 30 days to 3 years.
Reproduction
Eggs are laid in batches in soil near host nests, on stems, or foliage. The larvae are capable of consuming the immature host and its provisions, allowing them to survive as kleptoparasites.
Predators
Predators may include various insectivorous birds and arthropods that prey on beetles, particularly those that are not aposematically colored.
Ecosystem Role
Blister beetles play a role in pollination and as predators of bees, contributing to the control of bee populations.
Economic Impact
Toxicity of some species can lead to poisoning in livestock, particularly horses, when they consume contaminated alfalfa hay.
Health Concerns
Cantharidin, secreted by many species, can cause blistering of skin upon contact and is toxic if ingested. It is historically used in folk medicine as a remedy for warts but can be lethal if consumed in sufficient quantities.
Collecting Methods
- Netting from flowers
- Beat sheet collection
- Handpicking
Preservation Methods
- Ethanol
- Pinned specimens
- Spread specimens
Evolution
Began diversifying during the Early Cretaceous period; the oldest fossil is a larva from mid-Cretaceous Burmese amber.
Misconceptions
Some believe all blister beetles are harmful to humans; while they can be toxic, not all species cause harm if contact is avoided and they are not ingested.
Tags
- Blister Beetles
- Meloidae
- Cantharidin
- Pollinators
- Insect Behavior