Introduction

Centipedes are predators living in shady, moist microhabitats. They can be found under stones, moss and loose tree bark; in soil and rotting logs; in leaf and garden litter; down among the 'grass roots'; and even in seaweed heaps at the beach. Like spiders, centipedes catch, poison and eat other arthropods, and sometimes snails and worms as well. In Tasmania they are abundant in all habitats from sea level to mountaintops. For a brief, general introduction to centipedes see Edgecombe (2001a), and for a more detailed picture see Lewis (1981).

Before going to the identification page you should review a few anatomical basics. A centipede's body is something like a length of sausage tubing to which various hard plates have been attached. Along the back are the plates called tergites, and along the ventral surface are the sternites. There is generally one sternite for each pair of legs, but the leg-tergite relationships are more complicated. In Scutigeromorpha several tergites are fused together, and in Craterostigmomorpha and Geophilomorpha the tergites are subdivided. In Lithobiomorpha, tergites 2, 4, 6, 9, 11 and 13 are shorter than the others.

The head is the most complex structure in a centipede's external skeleton (see illustrations below). On top is the cephalic plate, which may or may not carry eyes but always carries antennae divided into segments called antennomeres. Below are the maxillipedes, which are modified legs used as grippers and poisoners. The maxillipedes start with a central plate, the coxosternite, which often has spines or tooth-like projections on its anterior border. The 'leg-like' parts of the maxillipede begin with a large femuroid and finish with an apical claw. From the side, the coxosternite in geophilomorphs has a taxonomically important coxopleural suture running from its base to the femuroid.

Left:  Dorsal view of geophilomorph head showing cephalic plate (pl) and right antenna with 14 antennomeres.
Centre:  Ventral view of same head, showing coxosternite (cst), and femuroid (fe) and apical claw (ac) on maxillipede.
Right top:  Ventral view of Henicops head; note 3 teeth on each side of anterior border of coxosternite.
Right bottom:  Left lateral view of head of geophilomorph, showing coxopleural suture (cs) on coxosternite.

A centipede leg consists (from base to tip) of a coxa, trochanter, prefemur, femur, tibia and tarsus. Spines at various positions on these leg segments are important characters. In the illustration below, take special note of the tibial spur, which is a flat projection on the anterior side of the tibia in some Lithobiomorpha. (Note that 'tibial spur' is actually a misnomer, the structure being more accurately called 'distal spinose projection of tibia'.) The tarsus ends in a large claw and may be subdivided. The rear leg coxae in many centipedes have ventral pits called coxal pores. The coxa of the last, backward-pointing leg in geophilomorph and scolopendromorph centipedes is fused with other structures into a coxopleuron.

Left top:  Generalised centipede leg showing coxa (Co), trochanter (Tr), prefemur (Pr), femur (Fe), tibia (Ti), tarsus (Ta) and claw (Tc).
Left bottom:  Portion of leg of henicopid lithobiomorph, showing tibial spur (Ts); in this leg the tarsus is divided into 3 parts.
Centre:  Ventral view of rear end of Lithobius showing pores (p) on ventral surface of last leg coxa.
Right:  Last segments of scolopendromorph, right ventrolateral view, showing pore area on coxopleuron (c).

Geophilomorph and scolopendromorph centipedes are born with the full adult complement of legs. Craterostigmomorpha, Lithobiomorpha and Scutigeromorpha all have 15 pairs of legs as adults, but have a smaller number of legs as juveniles.

Other anatomical features of importance in identifying centipedes are noted in the keys.