somatic precursor cell interommatidial precursor cell 2009-10-01T01:13:25Z inter-ommatidial precursor cell IPC FBbt:00007369 DISAMBIGUATION: There are at least two uses of this term. It is usually used, as here, only to refer to precursors of the secondary and tertiary pigment cells (e.g. Miller and Cagan, 1998). But it is also sometimes used to also refer to precursors of primary pigment cells (e.g. Larson et al., 2008), even though primary pigment cells are not interommatidial cells. fly_anatomy.ontology Precursor of the interommatidial cells (secondary and tertiary pigment cells). From approximately 27 hours after puparium formation (APF), 25% of these cells undergo programmed cell death and the rest differentiate. This produces a structured hexagonal lattice of six secondary pigment cells and three tertiary pigment cells surrounding each ommatidium. This lattice also incorporates three interommatidial bristles and is mature by 48 hours APF.