''Microdecemplex rolfei'' is the only known species of the extinct, small-bodied

millipede Millipedes are a group of arthropods that are characterised by having two pairs of jointed legs on most body segments; they are known scientifically as the class Diplopoda, the name derived from this feature. Each double-legged segment is a resu ...

order Microdecemplicida, a member of the extinct subclass Arthropleuridea. Fossils, measuring less than 10 mm in length, are known from the

Panther Mountain Formation The Panther Mountain Formation is a geologic formation in New York. It preserves fossils dating back to the Devonian period. It is located in the counties of Albany, Madison, Oneida, Otsego, and Schoharie. It is well known for its fossil art ...

New York State New York, officially the State of New York, is a state in the Northeastern United States. It is often called New York State to distinguish it from its largest city, New York City. With a total area of , New York is the 27th-largest U.S. sta ...

, dating to the

Middle Devonian The Devonian ( ) is a geologic period and system of the Paleozoic era, spanning 60.3 million years from the end of the Silurian, million years ago (Mya), to the beginning of the Carboniferous, Mya. It is named after Devon, England, w ...

. This species apparently lacks antennae and shows

sexual dimorphism Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most an ...

in its hind legs, which may be similar in function to the

telopod Millipedes are a group of arthropods that are characterised by having two pairs of jointed legs on most body segments; they are known scientifically as the class Diplopoda, the name derived from this feature. Each double-legged segment is a resu ...

s of male living

pill-millipede Pill millipedes are any members of two living (and one extinct) orders of millipedes, often grouped together into a single superorder, Oniscomorpha. The name Oniscomorpha refers to the millipedes' resemblance to certain woodlice (Oniscidea), also ...

s that are used to grasp females during mating.

References

Devonian myriapods Prehistoric myriapod genera Millipede genera Devonian arthropods of North America Fossil taxa described in 2000 {{Paleo-myriapod-stub