You can try something like this (using dummy data here):
r1 = range(-1.509400, -1.509490, 5001) # original range, but with 5001 samples
y = (sin.(r1.*400000) .+ cos.(r1.*100000).^2) # dummy data
# r1_ = 1:5001 # this range should have no discretization issues for Float32
r1_ = 5001:-1:1 # oops should reverse this.
tickvals = r1_[1:1000:end] # manually selecting tick locations
ticklabels = string.(r1[1:1000:end]) # select corresponding tick locations in original range
lines(r1_, y; axis=(xticks=(tickvals, ticklabels),)) # use clever makie trick ;)
Regular plotting:
lines(r1, y)
Edit: Oops! Had my first plot reversed, had to fix. Play around with how to get the best tick values.