• Source: Xanthisma gracile
  • Xanthisma gracile is a species of annual flowering plant in the family Asteraceae known by the common names slender goldenweed and annual bristleweed.


    Range and habitat


    It is native the southwestern United States and northern Mexico, where it grows in the deserts and plateaus.


    Growth pattern


    It is a bristly annual herb growing erect up to 45 cm tall.


    Leaves and stems


    The oval or oblong leaves are 1–3 cm long and divided into lobes or teeth tipped with bristles.


    Flowers and fruit


    The inflorescence bears one or more flower heads lined with pointed, roughly hairy phyllaries. The head has a center of many yellow disc florets and a fringe of 16 to 18 yellow ray florets roughly a centimeter long. The fruit is a woolly achene 2 to 3 millimeters long tipped with a pappus.


    Genetics


    Xanthisma gracile has extra chromosomes that do not have any functional genes (B chromosomes), and about which little is known.


    References




    External links


    Jepson Manual Treatment
    USDA Plants Profile
    Flora of North America
    UC Photos gallery

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