Mariza, perhaps the best-known exponent of Portuguese fado–the national song form of romantic longing and languor–has just added a special date in Chicago, performing August 2 at the Pritzker Pavilion in Millennium Park with the Grant Park Orchestra. (Fellow fadista Cristina Branco was originally scheduled to perform but recently pulled out.) Details of her repertoire aren’t available yet, and while she typically performs accompanied only by bass, acoustic guitar, the Portuguese guitar, and a touch of piano, she has given orchestral concerts in recent years, including a season-opener with the Los Angeles Philharmonic in 2003. Last weekend she performed with the Hollywood Bowl Orchestra in LA. The city is billing it as a concert of “Music from Brazil and Portugal,” an area she dabbled in on latest album Transparente, which was recorded in Brazil under the leadership of cellist and arranger Jacques Morelenbaum–a regular collaborator of Caetano Veloso.