Homozygous larvae hatch and begin crawling, but do not survive past the second larval instar.
100% of trachea in convY58/convR278 larvae fail to fill with air.
The trachea in mutant embryos appear normal through stage 15, but by stage 16 they become overly long and "convoluted".
Adherens junctions and septate junctions in the trachea appear ultrastructurally normal in stage 17 convR278/Df(2R)7131 embryos. At stage 16, the lumenal matrix of the trachea appears to be less dense and somewhat grainer than normal and some taenidial ridges are abnormal. By stage 17, the mutant lack the normal gap between the matrix and the lumen wall, and the taenidial defects are more pronounced.
Chitin accumulates normally in the tracheal lumen of convR278/convY58 stage 17 embryos. The gaps that normally appear between the lumenal walls the matrix are missing in these embryos.