I have had a look at this and found that you are inded correct. Back at dictionary J Taxon_List_Item key NHMSYS0100001982 with a  TV key of NBNSYS0100002527 was Coleophora lusciniaepennella in the Lepidoptera Micro list. Now  Taxon_LIst_Item key NHMSYS0100001982  with a TV key of NHMSYS0100001124 is Cotoneaster rotundifolius on  the NBN Gateway Vascular Plant Dataset. The change happended in Dictionary upgrade Z  with and entry dated 4/11/2011.

I have  compares the Dictionary as at J with the changes made in update Z and this is the only change to species which looks odd. However,  Taraxacum at Dictionary J has become Artrolobium in Z. Doubt if this will have any impact on data input, but not  sure what effect it had on the list. I would think this perhasp arises froma manual cahnge made by the NHM where keys got muddled up.

Perhaps we should give some though to checking that changes  made to the TV keys for a TLi key in an update are reasonable.

I have run a complete check from Dictionary J to the latest version looking for anything similar and fortunately I can't see anything. Changing the TV key for TLi key isn't something done very often and there were only 484 changes from J. Of this 294 had kept the same taxon name, which left only a few hundred to look through and these all seem reasonable changes apart from the one you found.  I will add a check into the dictionary processing to makle sure it doesn't happen again.