I am ready to concede that the captain's name is Jan Pieterszoon Eenarm

I have been calling this particular Medemblick Director's captain Jan Pieterszoon Renaren, but the evidence seems overwhelming that the correct name is something like Jan Pieterszoon Eenarm (or Eenarn). The last straw was the book De Sleutels van de Sont, which calls him by this name. He was a Medemblick Director's captain. He ship in 1645 was the Koning David (28 guns and a crew of 97 men). In 1652, he seems to have commanded the Sint Jeronimus (30 guns), also belonging to the Medemblick Directors. The ship was paid off late in the year when the crew refused to go to sea in her, due to her poor condition. The list from the Hollandsche Mercurius for 1652, republished in Vol.I of The First Dutch War was the source for Renaren. That list called him Jacob Pieterszoon Renaren. Hendrik de Raedt's list from August 1652 called him Jan Pieterszoon Eenarm (with a ship with 30 guns and a crew of 110 men).