We report on new nearby L and late-M dwarfs (d_phot_=3.0, later than M8.0) in the Galactic plane (|b|=M8.0), L and T dwarfs with accurate trigonometric parallaxes to calibrate the M_J_ versus I-J colour-luminosity relation. The resulting photometric distances have standard errors of ~15 per cent, which we used to select candidates dphot <=30pc. We measured proper motions from multi-epoch images found in the public archives ALADIN, DSS, 2MASS and DENIS, with at least three distinct epochs and time baselines of 10-21yr. We then used the Maximum Reduced Proper Motion method to select 28 candidates as ultracool dwarfs (M8.0-L8.0) and to reject one as a distant red star. Our low-resolution optical spectra confirmed that 26 were indeed ultracool dwarfs, with spectral types from M8.0 to L5.5. Two contaminants and one rejected by the maximum reduced proper motion cut-off were all reddened F-K main sequence stars. 20 of these 26 ultracool dwarfs are new nearby ultracool dwarf members, three L dwarfs within 15pc with one L3.5 at only ~10pc.
Cone search capability for table J/MNRAS/383/831/tables (26 nearby L and late-M dwarfs (tables 2, 3, 6 and 7 of the paper))
