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tokens: (host) galaxies are typically early-type (E/S0) galaxies, poor in gas (Whitmore, McElroy Schweizer 1987 ; Finkelman, Funes Brosch 2012 ; Reshetnikov Combes 2015 ). In contrast, the polar structures are generally younger, blue (e.g. Reshetnikov, Hagen-Thorn Yakovleva 1994 ; Iodice et al. 2002 ), with large amount (several times 10 9 M ⊙ ) of HI (e.g. van Gorkom, Schechter Kristian 1987 ; van Driel et al. 2000 ). Various scenarios have been proposed to explain the formation of the two kinematically and morphologically decoupled structures in PRGs: the capture of matter from an approached galaxy (Reshetnikov Sotnikova 1997 ; Bournaud Combes 2003 ), the merging of galaxies (Bekki 1997 , 1998 ; Bournaud Combes 2003 ), the misaligned accretion of matter from cosmic filaments (e.g. Maccio, Moore Stadel 2006 ; Brook et al. 2008 ), and some others. Observations show that several formation mechanisms can apparently be realized. Galaxies with polar structures are an important class of objects that allows us to study a wide range of problems, linked with the formation and evolution of galaxies under external accretion, and to study the properties of their dark haloes. Unfortunately, PRGs are very rare objects, with a fraction of ∼10 −3 of all galaxies in the local Universe (Whitmore et al. 1990 ; Reshetnikov, Faúndez-Abans de Oliveira-Abans 2011 ). Consequently, most recent studies of PRGs are concentrated mainly on a few relatively nearby and bright galaxies: NGC 4650A (e.g. Coccato, Iodice Arnaboldi 2014 , Iodice et al. 2015 ), A0136-0801 (Spavone, Iodice Arnaboldi 2015 ), NGC 660 (Smirnova, Wiebe Moiseev 2017 ), and some others. There were several attempts to collect large samples of such galaxies. Whitmore et al. ( 1990 ) have presented a photographic atlas of PRGs and related objects containing 157 galaxies but, according to further studies, only a small part of the atlas galaxies appeared to be true PRGs. The next important step was the catalogue SPRC by Moiseev et al. ( 2011 ) based on the results from the Galaxy Zoo project 1 (Lintott et al. 2008 ). The SPRC catalogue contains 275 objects split into four groups. The first two groups comprise ‘best candidates’ (70 objects) and ‘good candidates’ (115 objects) for PRGs. The remaining objects are related galaxies (mergers, strong warps) and possible face-on polar rings. A further study showed that an appreciable fraction of the SPRC objects are indeed PRGs (fig. 1 in Moiseev et al. 2015 gives several examples). In this work we present a new sample of ‘best’ and ‘good’ (in the sense of SPRC) candidates to PRGs. Our sample includes 31 galaxies compiled from Galaxy Zoo discussion boards. Throughout this article, we adopt a standard flat ΛCDM cosmology with Ω m = 0.3, Ω Λ = 0.7, H 0 = 70 km s −1 Mpc −1 . All magnitudes in the paper are given in the AB-system. 2 THE SAMPLE AND DATA REDUCTION 2.1 The sample To select new candidates to PRGs, we analysed discussion boards 2 of the Galaxy Zoo project. By