Great Diving Beetle
Dytiscus marginalis
This record describes Dytiscus marginalis (species). Recorded family: Dytiscidae. Recorded order: Coleoptera.
Identification and Appearance
One of our largest beetles, this species has a dark, olive-brown, almond-shaped oval body, about three centimetres long. The pronotum is completely bordered by a yellow margin - one of the key features that enables this species to be recognised in the field. The wing cases of the female are ribbed whilst those of the male are smooth. These beetles live in fresh water, either still or slow-running, and seem to prefer water with vegetation. All year round. Great Diving Beetles periodically come to the surface, extruding the tip of the abdomen to replenish an air supply kept under the wings. They are able to leave the water and fly off to colonise new ponds, sometimes landing in error on shiny car roofs or cold-frames in mistake for a water surface. Predatory as adults and larvae, eating anything they can tackle, including other water insects, tadpoles and even very small fish. The larvae are yellowish brown in colour, growing to about five centimetres in length, and possess a fierce pair of jaws - handle with care! They need damp soil by the edge of the water in order to pupate successfully.
Wikipedia reference for Dytiscus marginalis: http://en.wikipedia.org/wiki/Great_diving_beetle.
Classification
- Kingdom
- Animalia
- Phylum
- Arthropoda
- Class
- Insecta
- Order
- Coleoptera
- Family
- Dytiscidae
- Genus
- Dytiscus
Imported taxonomy record. Source availability varies; see the source references and editorial policy below.
Habitat and Range
Habitat
These beetles live in fresh water, either still or slow-running, and seem to prefer water with vegetation.
Seasonal Activity
All year round. Great Diving Beetles periodically come to the surface, extruding the tip of the abdomen to replenish an air supply kept under the wings. They are able to leave the water and fly off to colonise new ponds, sometimes landing in error on shiny car roofs or cold-frames in mistake for a water surface.
Diet and Behavior
Life History
Predatory as adults and larvae, eating anything they can tackle, including other water insects, tadpoles and even very small fish. The larvae are yellowish brown in colour, growing to about five centimetres in length, and possess a fierce pair of jaws - handle with care! They need damp soil by the edge of the water in order to pupate successfully.
Additional species information
Recorded status
Quite common and widespread in Britain.
About Primitive Winged Insects: the wider group
Order-level background for Coleoptera, the group containing Dytiscus marginalis. Species-specific details appear above.
Group overview
Coleoptera is the largest order of insects with over 400,000 described species, representing ~25% of all known animal species and ~40% of all insects. In the U.S. alone, nearly 30,000 beetle species have been identified.
Ecological role of the group
Beetles are prominent decomposers, especially in forests, breaking down dead wood and recycling nutrients. As predators, they reduce populations of pest insects. Many species are also important pollinators of flowering plants.
Economic and practical significance of the group
Beetles have major economic significance: leaf beetles (Chrysomelidae) and weevils (Curculionoidea) are among the most destructive agricultural pests globally, costing billions annually, while predatory species like ladybugs provide natural pest control.
Recorded sources for this group: Britannica, Smithsonian, NCSU Entomology. Imported estimates may describe particular regions or reporting periods.
Photos of Great Diving Beetle (2)
Frequently Asked Questions About Great Diving Beetle
What is Great Diving Beetle?
Great Diving Beetle (Dytiscus marginalis) is a species in the family Dytiscidae, within the order Coleoptera.
Where is Great Diving Beetle found?
Habitat: These beetles live in fresh water, either still or slow-running, and seem to prefer water with vegetation.
When is Great Diving Beetle active?
Great Diving Beetle: seasonal activity - All year round. Great Diving Beetles periodically come to the surface, extruding the tip of the abdomen to replenish an air supply kept under the wings. They are able to leave the water and fly off to colonise new ponds, sometimes landing in error on shiny car roofs or cold-frames in mistake for a water surface..
What is the life cycle of a Great Diving Beetle?
Predatory as adults and larvae, eating anything they can tackle, including other water insects, tadpoles and even very small fish. The larvae are yellowish brown in colour, growing to about five centimetres in length, and possess a fierce pair of jaws - handle with care! They need damp soil by the edge of the water in order to pupate successfully.