Well, here's how I would do it; this regex will populate $1 with the sigil, and $2 with the name if it is a variable like "$foo"; in the "<foo>" case, $1 will be undef and $2 will contain the name.

/
^                    # start
  (?:([\$\@\*\%])|<) # leading sigil or <
  (\w+)              # name
  (?(?{$1}) |> )     # if there was a leading sigil, match nothing;
                     # otherwise, match >
$                    # end
/x;
[download]

Another way might be to use this one:

/
^                       # start
  ([\$\@\*\%<])         # sigil
  (\w+)                 # name
  (?(?{$1 eq '<'}) >| ) # if the sigil is a '<', match the end;
                        # otherwise match nothing 
$                       # end
/x;
[download]

This is different in that in the "<foo>" case, $1 will be '<'.

In either case, theres no real reason to capture $3, since there is only one possibility that it could be(>), and you will know if the possibility is true or not depending on $1.