What plant containing single-seeded, blue-black drupes is part of the Manilkara zapota family?
Sideroxylon celastrinum Sideroxylon celastrinum is a species of flowering plant in the sapodilla family, Sapotaceae, that is native to Texas and Florida in the United States south through Central America to northern Venezuela and Colombia in South America. Common names include saffron plum and coma. It is a spiny shrub or small tree that reaches a height of 2 - . The dark green leaves are alternate or fascicled at the nodes and oblanceolate to obovate. Greenish-white flowers are present from May to November and are followed by single-seeded, blue-black drupes.
Billardiera heterophylla Billardiera heterophylla (formerly "Sollya heterophylla") is a species of flowering plant in the family Pittosporaceae, known by the common name bluebell creeper. It is native to Western Australia, but is grown as an ornamental plant in appropriate climates worldwide. It can sometimes be found growing in the wild as an introduced species or garden escapee, for example in other Australian states and in California, where it is popular in landscaping. It is sometimes considered a weed.