mab-19(
bx38), an EMS-induced recessive mutation, results in the variable loss of the three T-derived sensilla, rays 7-9. Preliminary lineage data (presented in a poster at the worm meeting in May, 1989) suggest that only the male-specific divisions of T and its descendents are affected.
bx38 does not affect the lineages of V5 or V6, from which the other six rays are derived. In the two animals we have observed, T.apap and T.appa or their descendants fail to divide.
bx38 males are almost infertile, but we do not know if this is related to T ray loss. We have localized
mab-19(
bx38) to LGX between -3.2 and -1.5.