Two new katydid species from Borneo exhibit stunning colour polymorphism!
While the males of the new species are a uniform green color, the females are standouts in red and pink. Not only that, both sexes look just like leaves, with distinctive veins and leaf-like lobes on their legs.
The insects, which live in northern Borneo, are especially unusual because one of them was identified based on photographs alone.
In 2013, a friend showed George Beccaloni pictures of a spectacularly colored katydid—a type of grasshopper-like insect—that Beccaloni couldn’t identify. Beccaloni sent them to Sigfrid Ingrisch, an expert on Asian katydids.
“He was reluctant to name and describe it because it’s not good practice to describe new species based only on photos,” says Beccaloni, a zoologist at London's Natural History Museum. “Often you need to look at microscopic characteristics, things that don’t show up in photos, to differentiate species.”
But in this case, the scientists felt confident naming the insect as a new species, Eulophophyllum kirki, since the veins of its wings were clearly visible and unlike any other known species. Wing veins are often used to tell katydid species apart.
The team also examined specimens of katydids collected from a 1993 expedition to Borneo and kept in a German museum collection. They decided that these specimens, along with photos they found on the Internet, represented a second new species of katydid, E. lobulatum.
In a recent study in the Journal of Orthoptera Research, Beccaloni and his colleagues classified both bugs in the genus Eulophophyllum, which was previously known from a single female collected in North Borneo almost a hundred years ago.
The two new species differ from the previously known specimen in the pink color of the females, the pattern of veins on the wings, and the presence of large, leaf-like expansions of their hind legs.
It's likely the newfound katydids aren’t the same color because they have different reasons for camouflage.
“The females of the new species almost certainly hide and maybe feed on young, red leaves,” says Beccaloni. “It’s possible the males evolved green camouflage so they can hide in more places while they are roaming around looking for females.”(...)