Pleurostigmomorpha
# Pleurostigmomorpha

Pleurostigmomorpha is a subclass of centipedes, containing all the orders except Scutigeromorpha. It contains 4 orders, which are subsequently divided into 15 families, 363 genera, and 3104 species.

The following physical and developmental traits can be used to separate members of the Pleurostigmomorpha from Notostigmomorpha:

* The spiracles are located on the sides of the centipede.
* The spiracles are deep, more complex, and always present in pairs.
* The head is somewhat flatter.
* The centipedes can develop through either anamorphosis or epimorphosis.

A 2022 paper reported that "Lithobiomorpha is the earliest diverging clade while the order Scolopendromorpha and the order Geophilomorpha cluster into one clade."

