Identification and characterization of sex-specific markers in the milky mangrove Excoecaria agallocha using double digest restriction site-associated DNA sequencing

•Two reliable sex-specific markers were identified using ddRAD sequencing in E. agallocha for the first time.•Sex ratios in the seeds and one-month-old seedlings of E. agallocha don’t deviate from 1:1.•The ddRAD method developed here can also be used to identify sex-specific markers in other dioecious plants.