Developmental defects observed in two interspecific crosses between <i>D. melanogaster</i> and <i>D. santomea</i>.

<p>In crosses of wild-type <i>D. melanogaster</i> females and <i>D. santomea</i> males, the majority of females (<i>X^mel/X^san</i>) emerge as adults. Those that fail to hatch from embryogenesis manifest cuticular defects typified by (A). Hybrid male embryos (<i>X^mel/Y^san</i>) from this cross usually die and show severe abdominal ablations (B). In crosses between <i>D. melanogaster C(1)RM</i> ♀ and <i>D. santomea</i> ♂, the majority of hybrid females embryos (<i>X^melX^mel/Y^san</i>) fail to hatch and show abdominal ablations (C), while hybrid males (<i>X^san/0</i>) usually survive. Those that fail to hatch are typified by (D).