The ornamental design for a discgolfmarker, as shown and described.
FIG. 1 is a top perspective view of a disc golf marker showing my new design;
FIG. 2 is a bottom perspective view of the disc golf marker;
FIG. 3 is a front elevational view of the marker;
FIG. 4 is a real elevational view of the marker;
FIG. 5 is a left side elevational view of the marker;
FIG. 6 is a right side elevational view of the marker;
FIG. 7 is a top plan view of the marker;
FIG. 8 is a bottom plan view of the marker; and,
FIG. 9 is an exploded perspective view of the marker showing the broken line of the measuring rule housing is included for the purpose of illustration and forms no part of the claim design.