part of developing embryonic structure gonadal sheath proper primordium somatic precursor cell male-specific somatic gonadal precursor cell 2025-02-17T17:23:06Z FBbt:00059362 fly_anatomy.ontology A cell of the mesoderm of parasegment 13 that contributes to the formation of the male gonad (DeFalco et al., 2003). These cells arise in both male and female embryos, but in female embryos are eliminated by apoptosis without contributing to the formation of the ovary. In male embryos, they join the posterior side of the coalescing testis at stage 13. msSGP