For 10 points, working in Naples and known by the nickname "Lo Spangoletto", this is what Spanish painter of The Clubfoot and The Martyrdom of St. Philip.
One work by this artist is dominated by the diagonal arrangement of a man trailing a reddish cape in the upper left, an angel in pink in the lower right, and the central figure in white and blue on a crescent and crowned with a halo of stars. In addition to his Immaculate Conception completed for the Agustinas Descalzas, this artist painted a violin in the lower left corner of a work in which three figures stand on the right behind a tree, looking at the title action, which produces an extremely detailed, open-mouthed grimace on one title character and the only bright hue in the painting, a bold pink representing that figure's muscle tissue. This painter of Apollo Flaying Marsyas painted a work in which a boy in torn clothes holds a piece of paper asking for alms and rests a crutch on his left shoulder and another in which a pale, emaciated man is tied to a crossbar being hoisted up. For 10 points, working in Naples and known by the nickname "Lo Spangoletto", this is what Spanish painter of The Clubfoot and The Martyrdom of St. Philip. 
One work by this artist is dominated by the diagonal arrangement of a man trailing a reddish cape in the upper left, an angel in pink in the lower right, and the central figure in white and blue on a crescent and crowned with a halo of stars.
Jusepe de Ribera [or Giuseppe Ribera or Jose de Ribera; accept "Lo Spangoletto" before "Lo Spangoletto" is said] 