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We investigate the theoretical scenario concerning the large sample ofvariables recently discovered in the dwarf, metal-poor irregular galaxy Leo A,focusing the attention on the "Anomalous" Cepheid phenomenon and itscorrelation with RR Lyrae stars, Classical and Population II Cepheids. To thispurpose, we make use of suitable stellar and pulsation models to depict thepulsational history of evolutionary structures with metallicity Z=0.0004,finding that He-burning pulsators are expected only outside the mass interval ~0.8-1.7 Mo. The dependence on metal content of this scenario has beeninvestigated over the range Z=0.0002 to 0.008. One finds that the edges of thepulsational strip for the more massive class of pulsators appear independent ofmetallicity, but with the minimum mass of these bright pulsators whichdecreases when decreasing the metallicity, thus decreasing the predictedminimum luminosity and period. Comparison with data for Cepheids in Leo A andin the moderately metal rich extragalactic stellar system Sextans A disclosesan encouraging agreement with the predicted pulsational scenario. On thisbasis, we predict that in a stellar system where both RR Lyrae stars andCepheids are observed, their magnitude difference may help in constraining boththe metal content and the distance. The current classification of metal-poorCepheids is shortly discussed, advancing the suggestion for an updatedterminology abreast of the current knowledge of stellar evolution.Comment: 18 pages, 10 postscript figures, accepted for publication on A&

Bright metal-poor variables: Why “Anomalous” Cepheids?