Platydesmida

Platydesmida (Greek for platy "flat" and desmos "bond") is an order of millipedes containing two families and over 60 species. Some species practice paternal care, in which males guard the eggs.

Description
Platydesmidans have a flattened body shape with lateral extensions (paranota) on each segment. They lack eyes, and have between 30 and 110 body segments. They measure up to 60 mm in length.

Behavior
While most millipedes feed on dead or decomposing leaf litter platydesmidans may be specialized to feed on fungi. Platydesmidans have also been studied with regard to parental investment, in that males of some species coil around eggs and young, a rare example of paternal care in arthropods. This behavior has been observed in species of  Brachycybe from North America and Japan, and Yamasinaium from Japan, all are in the family Andrognathidae.

Evolutionary history
The only described fossil of the order is from the Mid Cretaceous (~100 Ma) Burmese amber, belonging to the extant genus Andrognathus, several undescribed specimens belonging to the order are known from the same deposit.

Distribution
Platydesmidans occur in North America, Central America, the Mediterranean region of Europe, Japan, China, southeast Asia and Indonesia.

Classification
The order contains two families.

Family Andrognathidae Cope, 1869
 * Andrognathus
 * Bazillozonium
 * Brachycybe
 * Corcyrozonium
 * Dolistenus
 * Fioria
 * Gosodesmus
 * Ischnocybe
 * Mitocybe
 * Pseudodesmus
 * Sumatronium
 * Symphyopleurium
 * Trichozonium
 * Yamasinaium
 * Zinaceps
 * Zinazonium

Family Platydesmidae DeSaussure, 1860
 * Desmethus
 * Platydesmus