part of start stage end stage dermis portion of tissue scale primordium 2009-08-05T03:35:05Z A portion of tissue that gives rise to the scale. At the initial stages the primordium is composed of an accumulation of fibroblast below the basil epidermis. As the primordium develops the epidermis over the fibroblast alters: the basal epidermal cells become cuboidal and narrow, the collagen matrix remodels and the hemidesmosomes disappear. TAO:0002242 scale primordia zebrafish_anatomy Melissa Haendel scale placode ZFA:0001704 larval:days 21-29 juvenile:days 45-89