Tegrodera aloga

Tegrodera aloga is generally about 2 cm long; it has a long, narrow and cylindrical body and a wide head. The beetle is easily recognizable due to its contrasting yellow and red spots found on its black body. The brightness of the spots is due to the cantharidin toxins the beetle carries;[6] this coloration is known as aposematism, and it works as a warning signal to protect itself from predators. It is more common to find these beetles in larger groups rather than individually.

A few adults are nocturnal, but most are diurnal or show no cycle. Since adults are sociable and often highly colored, they tend to be conspicuous. The iron cross beetle love palo verde trees and they usually lay their eggs at the base of the flower buds. The eggs then tend to hatch when the flower bud opens. They pupate in the nest and emerge as adults the next spring. The iron cross beetle like most beetles have sexual reproduction. The species is very gender-scripted, with the male fighting to mate the female. Eggs are laid by the female in protected areas like under stones.

Adult iron cross blister beetles eat the flowers of Nama hispidum and Eriastrum spp.[7]

In Tegrodera aloga, cantharidin is excreted through the leg joints and the antennal pores.[8] It is toxic to humans and can inflict painful and sometimes fatal injury to certain livestock. This chemical, C₁₀H₁₂O₄, causes severe skin blisters (dermatosis) within hours after exposure. The insect secretes this substance as a defense mechanism. Crushing the beetle also releases the cantharidin.[8]

Cantharidin is a poisonous substance which can prove fatal if ingested. The lethal dose for humans when ingested is 10 mg,or 0.5 mg/kg of a human’s body weight. The main concern revolves around when the beetle is ingested by livestock, in particular horses.[9] The lethal dose for horses is 1 mg/kg. Iron cross blister beetles are known to be found in horses’ food, especially alfalfa. These beetles are starting to pose a problem for farmers in California due to them being “killed during harvest and incorporated into baled hay, or indirectly by transfer of the hemolymph from crushed beetles onto forage.”[10]

This beetle is also considered beneficial because cantharidin is used in the medical field as a topical medication in the removal of warts, removal of tattoos, and has even been looked into for certain cancer treatments.[11] Its use in the treatment of removing warts has been common for many years, and is still used by dermatologists.

• Blaisdell SR., Frank E. "SYNOPSIS OF THE GENUS TEGRODERA. (Order, Coleoptera; Family, Meloidæ.)." THE CANADIAN ENTOMOLOGIST 50.10 (1918): 333-35. Web. 16 Apr. 2015. .
• "Detailed record for Tegrodera aloga Skinner, 1903." Essig Museum of Entomology Species Lists. N.p., n.d. Web. 16 Apr. 2015. .