we determine and discuss the mass functions and age distributions of the groups. In Section\[members\] we discuss some interesting members, in particular those surrounded by circumstellar disks, and binaries. In Section\[motion\] we study the internal dynamics and expansion of the groups. [In Section \[conclusion\] we summarize and discuss the major results of our paper. ]{}

Detection of the Crux star forming region {#detect}
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Astrometric detection {#astdet}
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Parallel to the cluster search program described in , we ran an alternative search process better adapted to the finding of nearby co-moving groups. We give only a rough description of the procedure here as it is not crucial for this paper. The idea behind was to select a grid of convergent points homogeneously distributed over the sphere and to search for stars whose positions, proper motions and parallaxes are consistent with a given convergent point. We then selected stars which have at least 5 other stars within a radius of 10 pc around them and whose tangential velocities are consistent with the same convergent point. These we regarded as seeds of possible co-moving groups. Our search was restricted to stars having a parallax larger than 5.5 mas in TGAS. On the 