Smooththroat stoneseed (Lithospermum cobrense)
Same genus
- California stoneseed (Lithospermum californicum)
- Chinati stoneseed (Lithospermum calycosum)
- Carolina puccoon (Lithospermum caroliniense)
- Arizona stoneseed (Lithospermum confine)
- Narrowleaf stoneseed (Lithospermum incisum)
- American stoneseed (Lithospermum latifolium)
- Rough stoneseed (Lithospermum matamorense)
- San Antonio stoneseed (Lithospermum mirabile)