The suborder Myxophaga is the second smallest of the four

Suborders of Coleoptera (after Archostemata) in number of

species. It consists of two superfamilies, Lepiceroidea and

Sphaeriusoidea: the first with just one family, Lepiceridae,

and three species; the second with three families,

Sphaeriusidae, Torridincolidae, and Hydroscaphidae,

and a total of 102 described species. All species are small,

none exceeding 3 mm, and most live in aquatic, semiaquatic,

or hygropetric habitats, such as seepages, wet rocks under

waterfalls, hot springs, and salt marshes. Myxophaga are

rarely common, and although species are found in most

continents, their small size and the rare habitats they frequent

have left them poorly understood and rare in collections.

For such small beetles, Myxophaga have a rather long and

detailed fossil record, suggesting an ancient group that was

more abundant, diverse, and ecologically important in the

geological past. Myxophagan fossils are known back to the

Triassic period, more than 220 million years ago. One of

the earliest fossils was initially mistaken for Staphylinidae,

a much more recent family within the hyperdiverse suborder

Polyphaga, but that placement has now been disputed.

MYXOPHAGA

opposite | Satonius stysi (Torridincolidae) Larva

of this remarkable species, discovered in 2007 on

the Jade Dragon waterfall in Yunnan, China, and

named in 2008 after the distinguished Czech

entomologist Pavel Štys.