The propodium sports short spines , 0.04 millimetres ( 0.0016 in ) long , on the rear edge , while the petiole has a single longer spine , centrally placed ; this single spine is nipple - shaped .
Is the source of the species name .
The propodium sports short spines , 0.04 millimetres ( 0.0016 in ) long , on the rear edge , while the petiole has a single longer spine , centrally placed ; this single spine is nipple - shaped , and is the source of the species name .