Myxophaga is the second smallest suborder of Coleoptera

Beetle

Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...

 after Archostemata

Archostemata

Archostemata is the smallest suborder of beetles, consisting of fewer than fifty known species organized into five families. Archostemata is an ancient lineage with a number of primitive characteristics. They are similar in morphology to the first beetles, which appear in the fossil record...

, consisting of approximately 65 species of small to minute beetle

Beetle

Coleoptera is an order of insects commonly called beetles. The word "coleoptera" is from the Greek , koleos, "sheath"; and , pteron, "wing", thus "sheathed wing". Coleoptera contains more species than any other order, constituting almost 25% of all known life-forms...

s in four families. They have notopleural suture

Suture (anatomical)

In anatomy, a suture is a fairly rigid joint between two or more hard elements of an animal, with or without significant overlap of the elements....

s, although on some families the sutures may be difficult to see.

The members of this suborder are aquatic and semi-aquatic and feed on algae

Algae

Algae are a large and diverse group of simple, typically autotrophic organisms, ranging from unicellular to multicellular forms, such as the giant kelps that grow to 65 meters in length. They are photosynthetic like plants, and "simple" because their tissues are not organized into the many...

.

Only two myxophagan genera are found in North America: Sphaerius and Hydroscapha

Hydroscapha

Hydroscapha is a genus of beetle endemic to Europe and the United States.-External links:*...

.