Rhinogradentia

Rhinogradentia is a fictitious order of mammal invented by German zoologist Gerolf Steiner. Members of the order, known as rhinogrades or snouters, are characterized by a nose-like feature called a nasorium, which evolved to fulfill a wide variety of functions in different species. Steiner also created a fictional persona, naturalist Harald Stümpke, who is credited as author of the 1957 book Bau und Leben der Rhinogradentia (translated into English in 1967 as The Snouters: Form and Life of the Rhinogrades). According to Steiner, it is the only remaining record of the animals, which were wiped out, along with all the world's Rhinogradentia researchers, when the small Pacific archipelago they inhabited sank into the ocean due to nearby atomic bomb testing.

Successfully mimicking a genuine scientific work, Rhinogradentia has appeared in several publications without any note of its fictitious nature, sometimes in connection with April Fools' Day.

Rhinogradentia, their island home of Hy-yi-yi, zoologist Harald Stümpke, and a host of other people, places, and documents are fictional creations of Gerolf Steiner (1908–2009), a German zoologist. Steiner is best known for his fictional work as Stümpke, but he was an accomplished zoologist in his own right. He held a professorship at the University of Heidelberg and later the Technical University of Karlsruhe, where he occupied the department chair from 1962 to 1973.

According to Bud Webster, Steiner's motivation for the work was instructional, to illustrate "how animals evolve in isolation".

Steiner's fictional author, credited as "quondam curator of the Museum of the Darwin Institute of Hy-yi-yi, Mairuwili," provides a very detailed account of the order and individual species, written in a dry, scholarly tone. The evidently expert voice of the author, his competent writing, and apparent familiarity with conventions of academic literature set the work apart as a rare example at the intersection of fiction and scholarship. Steiner credits himself by name as illustrator of the book, and explains how that role led him to possess the only remaining record of Rhinogradentia.

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