trichoid sensillum fly_anatomy.ontology Note that there is some variation in usage of this term throughout entomology, with some sources using it to refer to any sensillum with a hair or bristle cuticular specialization (e.g. see Chapman, 1998 FBrf0239230). Among the Dmel model organism community it is only used for the smallest of hairs/bristle, with sensilla with larger, thicker cuticular specializations being referred to as chaetae. We follow this usage. It should be noted, however, that there is no clear dividing line between macrochaeta and microchaeta or between microchaeta and trichoid sensillum. A sensillum of which the external part is a seta. sensillum trichodeum VFB:FBbt_00005184 FBbt:00005184 hair sensillum eo-type sensillum