The conventional wisdom about music from colonial Mexico is that much of it was imported from Spain and Italy and the rest was slavish imitation. Not entirely, says Enrique Alberto Arias, a musicologist at DePaul University who compiled the intriguing, scholarly program for this Ars Musica Chicago concert, being given in conjunction with the Newberry Library’s exhibit “Mexico Illustrated.” Many of the liturgical and secular works performed at cathedrals, convents, and courts in Mexico City also reflect native influences, especially in their rhythms, and some of the Latin and Spanish texts contain allusions to African and Indian ideas. Moreover, a few of the works may have shaped the chaconne and sarabande dances favored by late Baroque composers. Most of the pieces on the hefty sampler–chants and Palestrina-style motets from the late-16th to the late-18th century–are from primary sources in the library’s collection that Arias rediscovered. Of particular interest is a Christmas cantata by Manuel Sumaye, a versatile composer of Indian ancestry. Also on the program, as an example of popular entertainment, is Tonadilla, a short comic opera from Spain, sung here by bass-baritone Andrew Schultz (who organized Ars Musica Chicago nine years ago), soprano Michelle Areyzaga, and tenor Luis Galvez under the direction of Stephen Blackwelder. Norman Ruiz will play guitar interludes throughout the program. Wednesday, 7 PM, Newberry Library, 60 W. Walton; 255-3700. TED SHEN