| Name | Macropiper guahamense f. glabrum (Yuncker) A. C. Smith |
| Authorship | (Yuncker) A. C. Smith |
| Rank | Forma |
| Placed in | Macropiper guahamense (C. de Candolle) A. C. Smith |
| Citation | 1975 Bot. J. Linn. Soc. 71(1): 18 |
| Holdings | 2 Specimens held in the Harvard University Herbaria identified as Macropiper guahamense f. glabrum (Yuncker) A. C. Smith |
| Identification made in | [no date] (2) |