@crsl4 : would you have time to look into this? I don't unfortunately...

See google group question and attached file, thanks to @brunoasm : it seems that mapAllelesCFtable! would return an empty list of repeated species, such that mergeRows() is not called during readTableCF! and the resulting DataCF object still has 13,757,814 4-taxon sets instead of a few 1000s:

CF = PhyloNetworks.mapAllelesCFtable("pnetworks_pops.txt","all_cf.csv") # 13,757,814 rows × 14 columns data frame
dataCF_summarized = PhyloNetworks.readTableCF!(CF) # DataCF, number of quartets: 13757814

yet mergeRows worked:

dataCF_summarized = PhyloNetworks.readTableCF!(PhyloNetworks.mergeRows(CF, [1,2,3,4,5,8,11,14]))# 2375 unique 4-taxon sets were found.

(used PhyloNetworks v0.11.0 and julia v1.5.1)