Is ‘Elfin’ Creeping Thyme Thymus Serphyllum Or Thymus Praecox?

Question

Your site says: “Elfin creeping thyme plant (Thymus serp[h]yllum) [maybe should be praecox, not serphyllum] is a low growing (1-2 inches tall) herbaceous perennial sub shrub with a dense mounding habit.” https://www.gardeningknowhow.com/edible/herbs/thyme/elfin-thyme-information.htm/?print=1&loc=bot

Answer 1

They are two different species, both referred to commonly as Elfin thyme or more appropriately, creeping thyme. The grower Monrovia, refers to the 'Elfin' variety as Thymus serpyllum 'Elfin,' as do several other reputable websites.

This article mentions both:
https://www.gardeningknowhow.com/edible/herbs/thyme/growing-creeping-thyme.htm

http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=256930
https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=255977&isprofile=0&
https://plants.ces.ncsu.edu/plants/thymus-serpyllum/