SRP409113 PRJNA904082 RNA-seq of gregarious and solitary Mythimna separata The larvae of M. separata show typical density-dependent polyphenism. Compared with solitary larvae, gregarious larvae are darker, and more active and voracious. In this study, we measured and analyzed the transcriptome of second-day sixth instar gregarious and solitary M. separata, and identified differentially expressed genes in gregarious compared with solitary armyworms.