By Marc Weingarten
Updated May 19, 2000 at 04:00 AM EDT

Musical magpies with a love for lulling gringo conjuntos, shambling roots rock, and frisky norteno, Calexico defy listeners to settle into a groove. On Hot Rail, the Arizona duo burrows deep into south-of-the-border territory, with authentic waltz-time instrumentals, then warbles murder ballads and emotional road-kill tales that sound like Will Oldham fronting a mariachi band. A-