Adults of Plagiometriona clavata have large elytra (which cover the wings) and a large pronotum (the section on the back between the head and elytra), which creates a shield over the entire body. This shield also covers the head. The shield looks like the shell of a tortoise. The elytra are clear with a brown design that is shaped like a teddy bear. The antennae are long and narrow, and stick out from underneath the shield. (Riley, 1986)
Plagiometriona clavata, the clavate tortoise beetle, is originally from the Nearctic region. It can be found throughout the east, central, and southern United States. (Barney, et al., 2007; Ciegler, 2007; Riley, 1986)
Plagiometriona clavata are leaf beetles that can be found on Solanum plants on farms or in gardens. They can also occasionally be found on the wild species of Solanum, usually in grasslands, meadows, and forests. (Riley, 1986)
Plagiometriona clavata goes through complete metamorphosis. Its life stages are egg, larva, pupa, and then adult. Eggs are laid on host Solanum plants, and they hatch after several days. Larvae develop through 5 to 6 stages, called instars, before pupating, often on the host plant. After pupation, adults emerge. (Chaboo, 2007; Riley, 1986)
Nothing is currently known about mating in this species.
Not much is known about mating in this species. It is likely that mating is similar to other known tortoise beetles. Adults mate and females lay eggs on the host plant. In the north, there is a single generation, but in the south, eggs are laid in multiple periods. (Chaboo, 2007; Riley, 1986)
Little is known about parental care in this species. Females likely leave nutrients in the eggs for the offspring to grow and develop. After that, there is likely no more parental care.
The adult lifespan of this species has not been recorded, but if it is similar to other tortoise beetles, Plagiometriona clavata likely lives a few weeks in the summer after becoming an adult. (Chaboo, 2007)
The larvae of most tortoise beetles, including Plagiometriona clavata, build fecal shields. Instead of getting rid of their waste, it collects on a fork that sticks out of the end of their abdomen. The fork holds the feces above the body like an umbrella. This shield gets bigger as the larvae grows and continues to eat. The shield does not seem to hide the larvae from prey, but it does work to keep predators from attacking. The shields may actually attract potential parasitoids, which lay eggs in the body of other insects and eventually kill the insect host, but this is not known for sure. (Chaboo, 2007; Nogueira-de-Sa and Trigo, 2002; Nogueira-de-Sa and Trigo, 2005; Olmstead and Denno, 1992; Olmstead and Denno, 1993; Vencl, et al., 1999; Vencl, et al., 2005; Vencl, et al., 2011)
There is little information about communication in Plagiometriona clavata, but it is known that the fecal shields the larvae build produce chemicals that keep away predators. Adults likely communicate with other beetles with sight and chemicals. They also view their environment with sight, and detect chemicals in the environment. (Nogueira-de-Sa and Trigo, 2002; Nogueira-de-Sa and Trigo, 2005; Olmstead and Denno, 1992; Olmstead and Denno, 1993; Vencl, et al., 1999; Vencl, et al., 2005; Vencl, et al., 2011)
Plagiometriona clavata eats several species of nightshade including Solanum dulcamara, S. americanum, S. carolinense, S. lycopersicum, S. pseudogracile, and S. tuberosum. Other plant hosts include species of Capsicum, Datura wrightii, and Datura stramonium. It eats the leaves of these plants. (Ciegler, 2007; Riley, 1986)
Plagiometriona clavata is eaten by ants, predatory Hemiptera insects, spiders and beetles as a larvae. For defense, larvae have a fork that extends from the end of their body that collects feces. While this does not camouflage the larvae, it does keep predators from attacking. Chemicals in the diet of the larvae, that are then present in the feces makes a chemical shield that repels predators. (Nogueira-de-Sa and Trigo, 2002; Nogueira-de-Sa and Trigo, 2005; Olmstead and Denno, 1992; Olmstead and Denno, 1993; Vencl, et al., 1999; Vencl, et al., 2005; Vencl, et al., 2011)
Plagiometriona clavata feeds on many Solanum plants, as well as several other plant species. However, it does not create enough damage to the plants to have any economic effect on farmers. It also prey for several different Arthropod predators. (Chaboo, 2007; Ciegler, 2007; Nogueira-de-Sa and Trigo, 2002; Nogueira-de-Sa and Trigo, 2005; Olmstead and Denno, 1992; Olmstead and Denno, 1993; Vencl, et al., 1999; Vencl, et al., 2005; Vencl, et al., 2011)
Even though Plagiometriona clavata does not currently cause much crop damage, it could become a crop pest in the future, which would cause economic loss for farmers.
Plagiometriona clavata is not an endangered species.
Michael Leasia (author), University of Michigan Biological Station, Brian Scholtens (author), University of Michigan Biological Station, Angela Miner (editor), Animal Diversity Web Staff.
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