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We detect the second known lambda Bootis star (HD 54272) which exhibits gammaDoradus-type pulsations. The star was formerly misidentified as a RR Lyraevariable. The lambda Bootis stars are a small group (only 2 per cent) of late Bto early F-type, Population I stars which show moderate to extreme (up to afactor 100) surface underabundances of most Fe-peak elements and solarabundances of lighter elements (C, N, O, and S). The photometric data from theWide Angle Search for Planets (WASP) and All Sky Automated Survey (ASAS)projects were analysed. They have an overlapping time base of 1566 d and 2545d, respectively. Six statistically significant peaks were identified (f1 =1.410 116 c/d, f2 = 1.283 986 c/d, f3 = 1.293 210 c/d, f4 = 1.536 662 c/d, f5 =1.157 22 c/d and f6 = 0.226 57 c/d). The spacing between f1 and f2, f1 and f4,f5 and f2 is almost identical. Since the daily aliasing is very strong, theinterpretation of frequency spectra is somewhat ambiguous. From spectroscopicdata, we deduce a high rotational velocity (250+-25 km/s) and a metaldeficiency of about -0.8 to -1.1 dex compared to the Sun. A comparison with thesimilar star, HR 8799, results in analogous pulsational characteristics butwidely different astrophysical parameters. Since both are lambda Bootis-typestars, the main mechanism of this phenomenon, selective accretion, may severelyinfluence gamma Doradus-type pulsations.

HD 54272, a classical lambda Bootis star and gamma Doradus pulsator