Autohaemorrhaging

Autohaemorrhaging or reflex bleeding is the action of animals deliberately ejecting haemolymph or blood from their bodies. If the animal has toxic compounds in its blood, then it may be an effective chemical defence mechanism.

Animals that autohaemorrhage include:

• Beetles
  • Meloidae (blister beetles) - their haemolymph contains cantharidin that they sequester from plants on which they feed.
  • Timarcha species
  • Chrysomelidae - their haemolymph contains anthraquinones.
  • Coccinellidae (ladybird, ladybug or lady beetles) - An alkaloid toxin is exuded through the joints of the exoskeleton, triggered by mechanical stimulation (such as predator attack).
• Hymenoptera
  • Sawfly larvae
• Orthoptera
  • Bushhoppers, such as Dictyophorus spumans, Phymateus viridipes and Phymateus leprosus - their haemolymph contains cardiac glycosides, sequestered from milkweed on which they feed.
  • Katydids, including Eugaster species
  • Armoured ground crickets
  • Enyaliopsis nyala
• Plecoptera
  • Stonefly larvae
• Phrynosomatidae lizards
  • Horned lizard - At least eight species are able to squirt an aimed stream of blood from the corners of the eyes, up to 5 feet (1.5 m).
• Snakes
  • Tropidophis, or wood snake, a genus of dwarf boa, which expels blood from the mouth, nostrils and eyes when disturbed.
  • Natrix natrix, or European grass snake, a colubrid, which secretes blood from the mouth and nose while playing dead.

See also

• Haemorrhage
• Autothysis