With his scruffy face and dressed-down demeanor,Felix Pastorius seems as relaxed onstage as a musician could. Yet as he plucks the strings of his bass, Pastorius wears an expression of focused curiosity, as if he is discovering the riffs as he goes. If a jazz fan saw the Floridian artist perform and had no idea who he was, Pastorius would seem effortlessly skilled. Related posts:PHOTOS: Grinding out the blues over the weekend, Barrio Amón ‘felt like New Orleans’ The Prague Ballet, an international blues festival, and other happenings around Costa Rica Hey NFL, are you out of your #$@% minds? Tico stand-up, founding father, and other happenings around Costa Rica Pastorius arrives in Costa Rica this week to play a two-night engagement at Jazz Café Escazú, southwest of the capital. At only 31 years old, Pastorius has played with the decades-old Yellowjackets, but for this concert he will arrive with his own quartet, The Social Experiment. If you’re familiar with the Pastorius dynasty – which goes back to his grandfather, the acclaimed drummer Jack – this concert should make you swell with nostalgia. But any jazz fan should appreciate Pastorius’ long, free-form jams.Felix Pastorius and The Social Experiment perform Sept. 25 & 26 at Jazz Café, Escazú. Fri. & Sat., 9 p.m. 20,000 ($40). Info: Jazz Café website. Facebook Comments But a serious jazz fan would probably know that Felix Pastorius is the son of John Francis Anthony Pastorius III, the acclaimed funk bassist known for his nickname “Jaco.” Jaco Pastorius collaborated with the Weather Report and Joni Mitchell, earning global acclaim for his musicianship before his accidental death in 1987. Friends and fans have long remarked about the uncanny similarity between father and son.