Praying Mantis species discovered
Some of the mantises play dead and fall from trees to the forest floor to avoid being captured Gavin Svenson

A scientist has discovered 19 new species of praying mantis from Central and South America.

The bark mantises were discovered in tropical forests and among existing museum collections.

Dr Gaving Svenson, curator of invertebrate zoology at The Cleveland Museum of Natural History, described the Liturgusa species in the journal ZooKeys.

Svenson collected the insects from eight countries in Central and South America, as well as gathering hundreds of specimens from 25 international museums in North America, South America and Europe.

Many of the newly found species are known only from a few specimens collected before 1950 from locations that have now been heavily impacted by agriculture or development.

Praying mantis drawing
The bark mantis species appear to be active hunters as opposed to ambush predators Gavin Svenson, Cleveland Museum of Natural History Illustration by Joshua Maxwell

He said: "This group, the Neotropical bark mantises, are incredibly fast runners that live on the trunks and branches of trees. This violates the common perception of praying mantises being slow and methodical hunters."

Like other varieties, bark mantises are highly camoflaged.

The group is flat in appearance and very difficult to locate because of their adept mimicry of bark, moss and lichen.

They often evade discovery by running to the opposite side of the tree before being noticed, an escape tactic also seen in many tree dwelling lizards.

Svenson added: "This is an amazing behavior for an insect because it shows that they are not only relying on camouflage like most insects but are constantly monitoring their environment and taking action to run and hide.

"In addition, some species leap off the tree trunk to avoid capture and play dead after fluttering down to the forest floor since none of the species are strong fliers."

As highly visual predators, the bark mantis species appear to be active hunters that pursue prey as opposed to ambush hunters that wait for prey to come close.

Similar to other bark mantis groups from Australia, this Neotropical species does not appear to exhibit cannibalism, which is an often misunderstood characteristic exhibited by some praying mantis species.

The research brings to light a previously unknown diversity of bark mantises. It indicates that there are many more species to discover.

Svenson said the research suggests there may be other species to discover: "Based on this study, we can predict that mantis groups with similar habitat specialization in Africa, Asia and Australia will also be far more diverse than what is currently known."

He added: "Many of these groups have never been studied other than by the scientists that originally described some of the species, which in some cases is more than 100 years ago.

"This is exciting because enormous potential exists for advancing our understanding of praying mantis diversity just by looking within our existing museum collections and conducting a few field expeditions."

The discovery of these 19 new species triples the diversity of the group that scientists thought had only a few species with broad geographical ranges. The research indicates that most species are far more restricted in their locations within regions of Central and South America.

This increased diversity and better measure of distribution has broad implications for conservation since many of the species were found in or near natural areas that may or may not be protected.

The conservation status of some of the new mantises found in museum collections is not known as they have not been seen since originally collected in the early 1900s and could be highly threatened or even extinct.

Liturgusa algorei, one of the new species, is named for Albert Arnold "Al" Gore Jr, former vice president of the United States of America, in honour of his environmental activism and efforts to raise public awareness of global climate change.