Annotate phylogenetic trees with bars or strips

Question

[Luca Arbore]

In a species barcoding project we have to compare the results of species delimitation by different methods. Can anyone suggest a way of plotting a figure in R like Figure 2 in https://onlinelibrary.wiley.com/doi/10.1111/1755-0998.12233

the problems I came across are:

1. geom_strip works if the strip is spanning minimum 2 tree tip. There are many single ones for which a gap would remain...
2. a heatmap where discordance between methods would be plotted like a mosaic of 2 colors (e.g. Fig 2 and 3 in https://www.mdpi.com/1424-2818/15/2/149)

I am also using iTOL webserver which is not very flexible for taxa display.

thanks