World’s first half-male, half-female, dual-gender stick insect discovered. Their name is Charlie

Charlie the green bean stick insect

London’s Natural History Museum has confirmed that the first known dual-sex stick insect has been discovered – and their name is Charlie.

Charlie is a green bean stick insect, or Diapherodes gigantea, who belongs to stick insect breeder Lauren Garfield who lives in Waldringfield, Suffolk.

Garfield shared photos of Charlie to her Facebook page, and said that she had “accidentally” bred a “gynandromorphic” stick insect.

A gynandromorph is a creature, usually an insect or a bird, that is both male and female at the same time. The two sexes of the animal are often split down their midline.

In Charlie’s case, one half of their body is a bright, apple green female, while the other half has the brown wings of a male.

According to the BBC, the Natural History Museum has confirmed that Charlie is the “first reported gynandromorph” in that species.

Garfield has donated her pet to the museum, but Charlie will sadly have to be euthanised for research because the insects shrivel rapidly after natural death.

Green bean stick insects live for around a year on average, and Garfield wrote on Facebook: “I do feel bad about it – but as it was fully grown it wouldn’t live much longer anyway and at least this way it’ll be preserved.”

Paul Brock, an insect expert at the Natural History Museum, told the BBC that Charlie was a “noteworthy” and “particularly impressive specimen”.

He said: “Many rearers of stick insects never see a gynandromorph.

“In 1958, an author showed a likelihood of 0.05 per cent for the occurrence of gynandromorphs for the laboratory stick insect Carausius morosus, kept in culture in Europe and elsewhere since 1901.

“Lauren’s specimen has a largely brown (male) body form on the right hand side, with full length hind-wings. The left hand side is not as broad as a typical adult female, but broader than a normal male and mainly apple green, as in a normal female.

“In a gynandromorph, including this individual, the genitalia are not properly formed so although male-like, it would not be able to mate properly with a female.”

Charlie is not the first creature to exist outside of binary gender and sex.

Last year, scientists in Japan discovered a new species of freshwater algae that has naturally evolved to have three different sexes, which can all mate with each other.

There are examples in nature of sequential hermaphrodites, animals that naturally change their sex from one to another, like clownfishes, oysters and other shellfish, while cases of “gender fluid” animals have also been observed.

For example, one lioness in Botswana grew a mane and started roaring like a male to fool invading prides.