Prosternum underlying the proboscis.
Proboscis free, not supported from below by either the prosternum or the basal segments of the appendages of the 2nd pair.
Sternal elements of prosoma almost entirely absent, traces of a prosternum and metasternum alone remaining.
Rostrum free, not supported by either the prosternum or the basal segments of the appendages.
In the thorax the pronotum and prosternum are closely associated with the mesothorax, but the pleura of the prothorax are usually shifted far forwards, so that the forelegs are inserted just behind the head.