Pyrena
This article is about a subject of plant anatomy. For other uses of Pyrena or Pyrene, see Pyrene (disambiguation).
Not to be confused with pyrenoid, an organelle within the chloroplast of some algae and hornworts, or with Pirene
Pyrena or pyrene is the name for the stone within a drupe or drupelet. It consists of a seed surrounded by hard endocarp tissue.[1][2]