A total of 30.79 GB clean data was obtained from the transcriptome analysis of four V. aspersus samples and the average clean data was 7.70 GB (Table 1). All clean data was assembled by Trinity (https://github.com/trinityrnaseq/trinityrnaseq/wiki ). The total number of unigenes and transcripts were 44,623 and 65507, respectively, and sequences with length between 0 and 500 bp accounted for the largest proportion (unigenes, 46%; transcripts, 43%) (Fig. 1). 6201 SSR-tagged sequences and 7878