Fornax cluster projected density field. The background image shows the projected density field on a log scale, produced by Gaussian smoothing the luminosity ratio relative to the BCG (NGC 1399), at the position of each galaxy. The (black and white) contours emphasise the density field, where the lowest shows the influence of M_⋆ ≃ 5 × 10⁹ M_⊙ and increases by 2ⁿ. The grey dotted line shows the border of our observed area (same as Fig. 2), and the pink dashed circle is 0.25 R_vir. Black crosses and open black circles are the H I-undetected ETDs and LTDs. The filled circles and thick crosses are the H I-detected ETDs and LTDs, which have been labelled and coloured by their M_HI. LTDs with disturbed H I morphologies are enclosed with dashed black circles. Black diamonds show the intermediate galaxies and the white triangles are the massive galaxies. The projected substructure is dominated by the brightest (hence most massive) galaxies, and the H I-detected dwarfs avoid the most massive potentials (i.e. cluster centre and massive galaxies) in the cluster.