Lactuca muralis
Name: Mycelis muralis.
Botany
Lactuca muralis is a slender, hairless herb, ± 50 cm tall; stems purplish stems, exudes a milky juice; leaves red tinged, lyre shaped, pinnate shaped; lobes are triangular in shape the terminal lobe being the largest; upper leaves are stalkless, smaller and less lobed; achenes are short beaked, spindle shaped and black; pappus has simple white hairs, the inner longer than the outer; flower heads yellow, small, with only 4-5 yellow ray florets, in loose panicle.
Taxonomy
Lactuca muralis is similar to Lactuca serriola and Lactuca virosa, but clearly distinguished having only 5 florets.