LOS ANGELES — Zoo animals remain hot at the box office. Singing stars and Adam Sandler are not.

Ben Stiller and his voice co-stars of ‘‘Madagascar 3: Europe’s Most Wanted’’ held on to the No. 1 spot again, with $35.5 million for the animated sequel’s second weekend in domestic theaters.

Studio estimates Sunday put Ridley Scott’s sci-fi adventure ‘‘Prometheus’’ at No. 2 again with $20.2 million.

‘‘Madagascar 3’’ and ‘‘Prometheus’’ held off two underachieving newcomers. The star-studded musical ‘‘Rock of Ages,’’ whose cast includes Tom Cruise, Catherine Zeta-Jones, and Alec Baldwin, flopped at No. 3 with $15.1 million.

Sandler’s ‘‘That’s My Boy’’ bombed with $13 million, the worst showing for one of his broad comedies since the mid-1990s. ‘‘That’s My Boy’’ came in at No. 5, behind the $13.8 million for ‘‘Snow White & the Huntsman,’’ a film that’s been out for three weekends already.

‘‘Sure, we would have liked to have done more,’’ said Rory Bruer, head of distribution at Sony, which released ‘‘That’s My Boy’’ and most of Sandler’s movies. ‘‘But you’ve got to give it to Adam. He mixes it up. This is a really off-the-wall comedy.’’

‘‘That’s My Boy’’ stars Sandler as a guy who became a fleeting teen celebrity after getting his seventh-grade teacher pregnant and now is a middle-aged loser trying to reconnect with his son (Andy Samberg).

The R rating for ‘‘That’s My Boy’’ may have cut into the movie’s business, prohibiting those under 17 from seeing it without an adult. Sandler’s comedies usually are rated PG-13.

Between ‘‘Rock of Ages’’ and ‘‘That’s My Boy,’’ Hollywood fell back into a pattern that persisted at the start of summer season in May as new movies debuted weakly, unable to dislodge strong holdovers.

The superhero tale ‘‘The Avengers’’ has dominated so far, remaining in the top 10 after seven weekends, its $8.8 million take raising its domestic total to $586.7 million. The film has taken in $1.4 billion worldwide.