'Uniquely shaped male reproductive organs' help identify new insect species

A new species of rainforest insect, whose closest relative was last seen in 1969, was identified by its uniquely shaped male reproductive organs, its finder has revealed.

The new type of leafhopper was found in Uganda by Dr Alvin Helden, of Anglia Ruskin University (ARU), who swept a net through vegetation at Kibale National Park.

Dr Helden said he noticed under a microscope the male bug was of a new species due to the shape of its reproductive organs, which have a bit that looks like “little leaves” and is “towards the tip of the structure”.

The 6.5mm-long male bug’s species was named Phlogis kibalensis.

Prior to the new discovery, made in 2018, the last recorded sighting of a leafhopper from the rare genus was in Central African Republic in 1969.

Dr Helden said many different species of leafhopper “look very similar, so from the outside it’s very difficult to tell which they are”.

“So the way we have to do that is to actually look at the male genital structures, and you find that their genital structures have unique shapes,” he said.

“Often they’re quite intricate and sometimes quite bizarre in shape.

“This particular species has its own unique shape.”

He said that “towards the tip of the structure” there is a part that looks like “little leaves”.

“Insects have external skeletons and the male reproductive structures – the equivalent of what we would call a penis – of course has to be inserted in to the female,” he said.

“The male structure has got to be just the right shape to go in to the female.

“Each species, in order to reproduce successfully, has to have its own structures.”

Leafhoppers feed mainly on plant sap and are preyed on by invertebrates, including spiders, beetles, and parasitic wasps, as well as birds.

Dr Helden, a member of the Applied Ecology Research Group at ARU, said: “To find this new species is a once-in-a-lifetime achievement, particularly as its closest relative was last found in a different country over 50 years ago.”

He added: “Being able to look down a microscope and think, ‘I’m the first person ever to have seen this,’ – that’s quite exciting.

“In life, there’s not many things that you can say I’m the first person to ever do this.

“It would be lovely to be able to discover more about this species.”

Dr Helden said it is unknown which plants the newly-discovered insect species feeds on or what its role in the local ecosystem is.

“There is so much still to find out, not just about this species but so many others, including the many species that are still waiting to be discovered,” he said.

“It is incredibly sad to think that some species will become extinct before we are even aware of their existence.

“There are some wonderful places, like the Kibale National Park in Uganda, where wildlife will survive. But outside national parks and reserves, the amount of rainforest that has been cleared in the tropics is devastating.

“Rare species could be living anywhere, but deforestation means it is inevitable that we will be losing species before we have discovered them.”

The discovery was announced in the journal Zootaxa.