Ena & Jiwon - Different Types of Cic...

Different Types of Cicadas and their Adaptation

This article is about the different types of cicadas (periodical and annual cicadas), their characteristics, and how they adapt to different habitats. Why do cicadas not emerge every summer in the United States unlike in Asia? Find the answer by reading this article!

Firstly, where did cicadas originate from? Paladeontinoidae is an extinct superfamily of cicadomorph which is the infraorder cicadas belong to. Paladeontinoidae is known as giant cicadas (their forewings reached 57 to 71mm when average periodical cicadas are about 24 to 33mm long from top to bottom) and they existed in Eurasia and South America during the Jurassic or Lower Cretaceous period. The early paladeonitids had short and broad hindwings, which shows that they were fast but moderately versatile fliers. On the other hand, later paladeonitids had smaller and narrower hindwings which indicate that they were highly versatile and could fly with a wide range of speeds and agility similar to modern wasps. We can say that they were the first cicadas and originate from a variety of places not just from a specific area.

Today, there are two major species that cicadas can be categorized into: periodical and annual. Both species have similar above-ground life cycles. After emerging, males cluster in groups and produce loud sounds for around 2 weeks to attract females to mate with. After mating, female cicadas excavate furrows in tree branches and deposit their eggs. Over the next month, each female can lay from 400 to 500 eggs. The larvae hatch, drop to the ground and burrow beneath the soil again and begin feeding on roots under the soil. Depending on the species, the year that each brood will emerge is easily predicted by counting forwards 17 (periodical) or 1 or 2 (annual) years from their last emergence as this is their cycle length. Periodical cicadas, mostly present in America, emerge earlier in the year from April to May. They generally appear in much larger numbers than annual cicadas making us able to hear their stridulation from miles away. Annual cicadas - which we are more familiar to - emerge every July and August.

They have a difference in physical appearances and life patterns too. Adult annual cicadas have black, green patterned bodies, transparent silvery wings and black or brown eyes with double the size of the periodical cicadas, whilst adult periodical cicadas have black bodies, transparent yellow wings and red eyes. In addition, periodical cicadas have highly synchronized life patterns and live up to 17 years; annual cicadas have life patterns that aren’t synchronized, making some of them emerge at a different time to others, and have life spans up to only 2 to 5 years.

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Where we can find them depends on their habitat. Periodical cicadas are associated with deciduous trees and shrubs. On the other hand, annual cicadas are most common in forested and wooded areas such as parks and forest borders as their eggs are laid in tree twigs and nymphs depend on the tree roots for their nourishment. Adult cicadas can fly anywhere, but they rarely go far from the trees, where males do most of their singing and females lay their eggs. Cicadas are minimally impacted by predation as their adult stage only needs to survive for a short time to mate and lay eggs. Moreover, there are so many of them that this is barely an issue. However, in their larval form, they must survive for 17 years in the soil: large earthworks, deforestation, insecticides, and residential developments can decrease its population. For this reason, periodical cicadas are a more vulnerable group of cicadas.

Sometimes cicadas also adapt to their habitat. Cicadas in Australia are quite unique in both their appearance (as they are very colourful) and habitat. Australian cicadas are found in almost every part of Australia: hot and wet tropical islands, cold coastal beaches, high and low deserts, alpine areas (high mountains), snowfields, gardens and large cities like Sydney, Melbourne and Brisbane. Most Australian species are found in the northern half of the continent as cicadas are originally tropical insects, and so the great variety of vegetation types and perfect climate makes the northern part the richest region for species. However, Australian cicadas differ from many other types of cicadas around the world because of the continent’s diverse climate and terrain; the plants they inhabit range from the tall trees to lawns, coastal mangroves to desert shrubs resulting in them to inhabit a variety of places. For example, one of the most common species in Australia is called the green grocer. They are unusual in their ability to adapt perfectly to the urbanised environment and so are found in the middle of busy cities.