---

I don't know about the botanical rules, but you can find the online zoological rules (the 'International Code for Zoological Nomenclature' or 'ICZN' or simply 'the Code' ) right here.

If you would remove the abbreviation 'var.', you are in fact upgrading the status of the taxon to subspecies.

For example, if you write
Canthon septemmaculatus var. lineatus
you are using an infrasubspecific name (a name denoting a taxonomic level lower than subspecies). Such names are currently not governed by the ICZN.

If you remove 'var.', you get
Canthon septemmaculatus lineatus
which is a subspecific name and thus governed by the ICZN. Any name behind a specific name is automatically a subspecific name, unless it is clearly denoted as a var(iety), ab(beration), f(orma) and so on. See the Code for more details and the correct abbreviations.

I would thus suggest you remove the abbreviation 'subsp.' because it does not add any additional info, but I recommend you leave the other abbreviations in place or remove those infraspecific names (and keeep the example as Canthon septemmaculatus). Of course, varieties can be upgraded tot subspecies, subspecies upgraded to species, abberations synonymized with species etc. etc., and taxonomists may not agree with eachothers views (think e.g. of splitters versus lumpers). You should always best use the most recent literature as well as your own common sense as to which view you adopt.

Keep in mind that most subspecific and infrasubspecific names are used for large and colourful species (butterflies, flower chafers etc.), while 'boring' small brown bugs will almost never get a name beyond specific level, even though their infraspecific genetic variation may be larger. I guess such names have often more to do with aesthetics and profits than with taxonomy.