FlyBase curator comment: this entry is used to capture phenotypic information when the particular allele (or allele combination) used by the author could not be determined but the context of the experiment suggests that the phenotype being described is some kind of loss of function.
Ventral furrow fails to form.
Homozygous embryos are partially dorsalised. The ventral furrow is missing and the embryo is twisted and coiled in the egg case, often with the posterior side up. No maternal effect is seen in germ line chimeras. Heterozygous embryos have delayed ventral furrow formation.