Monarch Buttefly
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In 1963, the first Type B Metamorphosis larva (Type B -- D. plexippus as known as the Monarch Butterfly) was found in a small town of North America. Initially, it was misidentified as a caterpillar fungus which resulted from a parasitic relationship with a Cordyceps fungus, commonly on caterpillars and spiders. This fungus is mainly found in
China and used as a medical agent. Unlike caterpillars fungus, Type B is also poisonous due to the presence of cardenolide aglycones in their body, similar to other related mutations of the Monarch Butterfly. Fortunately, no deaths or serious hospitalizations have been reported from mistaken use in medical treatments.
There have been a number of attempts made to theorize the origin of the Type B mutations, but the evolution of these traits is still under investigation. One of the first theories identified a high correlation between the appearance of Type B with the diminishing presence of milkweed plants, which is the primary food source for these caterpillars. This conclusion was gathered because Type B cases are able to produce a large number of butterflies for each larva, which resulted in a butterfly population that was far larger than the regular populations for the given amount of milkweed plant present. However, this was countered by a later discovery of Type B in an isolated region of Australia where a large increase of milkweed plants was recorded. The introduction of the Type B species into new environments seems to be increasing which will help future research understand the history of its evolution.
Observations of Type B were commonly made of caterpillars because of the more naturally recognizable similarity to other caterpillars. The later stages as a plant-like insect are much harder to detect. Additionally, the pupa stage, which forms a bulb like shape, grows a number of roots which helps the growth and reproduction of Type B.
It takes 3 to 4 months for Type B larva to grow into its matured plant-like stage. In contrast, it takes 5 days for it to molt and have many butterflies emerge out of its flower like stem. The caterpillar eggs form as a sort of fruit, which drop from the stem and hatch new larva during the molting of the chrysalis. This rapid process begins and ends quickly making it rare to observe in the wild. Type B is classified as an insect in spite of the fact that it spends most of its lifespan as a plant.