A work entitled Still life with fruit and oysters on a table dated 1666 (At Sotheby's New York, 22 April 2015, lot 11) indicates that his career should be situated in the latter half of the 1660s.
[1] In terms of composition and choice of motifs his work shows the influence of Jan Davidszoon de Heem, a Dutch still life painter who was active in Antwerp from the mid-1630s.
He even produced copies of the work of de Heem.
[2][3] Another artist who influenced Mertens was Joris van Son, whose technique and preference for smooth finishes he shared.
[4] His work is further similar to that of other artists who were influenced by de Heem such as W. Mertens with whom he may have been related.