Also known as bullion knot, coil stitch, grub knot, Porto Rico rose, post stitch or worm stitch.
Source: TORTORA, Phyllis G. and Ingrid JOHNSON (2014). The Fairchild Books: Dictionary of Textiles, 8th edition, London: Bloomsbury, p. 83.
Digital source of illustration (retrieved 29 May 2016)
GVE