large basiconic sensillum of antennal segment 3 antennal basiconic sensillum ab1 A large olfactory basiconic sensillum of the antenna that houses the highly branched dendrites of four ORNs (Shanbhag et al., 1999), expressing Or42b, Or92a, Gr21a and Or10a (Grabe et al., 2016). It has a pore size of about 100 nm and a pore density of about 30 pores per square micrometer (Shanbhag et al., 1999). There are more of these sensilla in females than males (Grabe et al, 2016). fly_anatomy.ontology basiconic sensillum LB-II4 FBbt:00067012 VFB:FBbt_00067012 sensillum basiconicum LB-II4