17th century "Martyrdom of a saint" is related to Simon de Vos and Frans Francken
Carlo Bonte, from Belgium, sells on 13 June 2018 a "17th century, unsigned" Martyrdom of a saint, estimated at 600 to 800 Euro.
This rather lage (55 by 72 cm) oil on copper is probably a depiction of the beheading of Saint Paul, and seems to be the work of Simon de Vos or someone from his circle. His depiction of the same story, now in the Royal Museum of Fine Arts in Antwerp, shows many similarities, especially in the way the executioner is shown. The white horse with yellow decoration is also a typical De Vos element.
While the composition reminds me most of Simn de Vos, the style of painting is closer to the Francken family. The above poor picture shows a martyrdom of Saint Catherine which is attributed to Frans Francken II, and where the position of the executioner and the horse are similar to the work for sale (although the genral posture is closer to the Simon de Vos actually, but the clothing is more like the Bonte work).
Even as an anonymous Flemish work, this one should fetch 2,000 to 3,000 Euro.