Large-scale spatial distribution of all targets observed at low and/or high resolution. Circles refer to sources observed spectroscopically in this work, while triangles are targets analyzed by Alcalá et al. (1996) and Alcalá et al. (2000). The symbol size increases with the lithium equivalent width (0,  < 150, 150–300,  > 300 mÅ). The arrows refer to stars for which we measured the iron abundance (downward for  [Fe/H]  ≤  −0.14, horizontal for  −0.14 <  [Fe/H]  ≤ 0.06, upward for  [Fe/H]  > 0.06; the central bin corresponds to the average metallicity of our targets  ± 1σ). Dotted lines represent the strip, long-dashed line is the Galactic plane, while dash-dotted lines represent the Gould Belt disk, as outlined by Guillout et al. (1998). The CO J = 1 → 0 emission contour maps by Dame et al. (2001) of the Orion, Monoceros, and Taurus molecular clouds, and the λ Orionis H ii region are also overlaid.