hey don, looked it up and description/pictures of the bug i have on my filamentosas, gloriosas looks like the yucca bug. they start out small, flattish, black or nearly so, very fast moving, maybe a fourth inch across when almost adult.. if not controlled can cause a severe decline of the infested plant, often with a yellow discloration to foliage. typically come out in april in this area. in driving around have noticed several yuccas with an similar infestation. hope this helps! finally a string of nice warm dry weather with several days 80f or better. am so ready for srping! randy