Genome size estimation
To estimate the T. ichikawai genome size, k-mer frequency analysis was performed using KmerGenie (Chikhi and Medvedev, 2014). First, stLFR barcodes in the MGISEQ reads were trimmed by the stLFR2Supernova pipeline (Wang et al., 2019). Second, the best k-mer length was estimated from the barcode-trimmed reads. Third, genome size was estimated from the frequency distribution of the best k-mer length.