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Most of the living things on Earth lie in the shadows, undiscovered by science. Even conservative estimates hold that only 13 to 18 percent of organisms have been identified and described. The task of discovering, describing, and naming these species may seem daunting, but for the scientists seeking to impose order on this chaos, there are always surprises. Such was the case for a team of researchers that unearthed a previously unknown species of spider tucked away in the forests of western Thailand. Not only did they find a species that had escaped the notice of the scientific enterprise, they found a rare individual that was half male and half female.
The species, described for the first time in the journal Zootaxa by scientists from the Center of Excellence in Entomology at Chulalongkorn University in Bangkok, displays striking physical differences between the sexes. The female is larger—about one inch in length—with a distinct orange coloration, while the male is roughly half that size and appears grey due to a mysterious white substance covering its body.
The individual could be the result of a loss of sex chromosomes due to a nematode infection in a female embryo.
Among the orange and grey arachnids collected by the research team was an oddball—a specimen that was half orange and half grey. The researchers investigated this specimen and found that this particular spider was a rare gynandromorph.
Gynandromorphs differ from the relatively more common hermaphrodites in some key ways. While hermaphrodites possess both female and male sex organs, they still display normal, bilateral symmetry—both halves of the organism appear as mirror images. Gynandromorphic individuals, on the other hand, display bilateral asymmetry; one side is female, while the other is male. While the causes of gynandromorphy in this specimen are unknown, the authors say the individual could be the result of a loss of sex chromosomes due to a nematode infection in a female embryo.
Such a colorful spider deserves a colorful name, and the scientists gave this species a particularly apt one. Researchers dubbed their find Damarchus inazuma after the character Inuzama from the manga One Piece for a couple of reasons. Firstly, Inuzama the character possesses the power to shapeshift from female-presenting to male-presenting. Secondly, similar to the D. inuzama gynandromorph, Inuzama is always dressed in orange and white, split right down the middle.
Assuming the researchers’ classification of D. inuzama is confirmed by molecular data, this is the first documented example of gynandromorphy in Bemmeridae, a family of funnel web trapdoor spiders spread across Asia and Africa. 
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Lead image: Damarchus inazuma: (Fig 6a: Kunsete et al., 2025:
https://doi.org/10.11646/zootaxa.5696.3.6). ©Magnolia Press. Reproduced with permission from the copyright holder.
