T.E.R:R.A.I.N - Taranaki Educational Resource: Research, Analysis and Information Network

Solanum nodiflorum (Small flowered nightshade)

Kingdom:   Plantae
(Unranked):        Angiosperms
(Unranked):        Eudicots
(Unranked):        Asterids
Order:       Solanales
Family:      Solanaceae
Genus: Solanum
Species: S. nodiflorum
Binominal name: Solanum nodiflorum
Synonym: Solanum americanum, S. americanum subsp. nutans, Solanum nodiflorum subsp. nutans. 
Common Name: Small flowered nightshade

Parts of this plant is poisonous

Solanum nodiflorum is indigenous to New Zealand occurs in scrub, forests and plantations especially in coastal areas mainly in the North Island through the South Island it is has been reported in Nelson, Marlborough, North Canterbury and Westland. It also occurs on the northern of shore islands where it flourished in the areas manured by seabirds. It is also present also in Australia, Africa, India, south-east Asia and the Pacific.
Solanum nodiflorum (Small-flowered nightshade)was previously known in New Zealand as Solanum americanum is easily confused with Solanum nigrum (Black nightshade) which was introduced to New Zealand. They differ in chromosome numbers but appear very similar externally.  Flora of New Zealand Volume 4 suggests that in:

Solanum nodiflorum

* The calyx is strongly reflexed at fruiting.

* The flowers/fruit in a particular group all branch from more or less the same point.

* Stone cells are evident in the fruit.

Solanum nigrum

* The calyx is not or only partially reflexed at fruiting.

* Some flowers/fruit in a particular group clearly branch below the others.

* Stone cells are usually absent in the fruit.

For more detail details visit: http://www.nzpcn.org.nz/flora_details.aspx?ID=2262

NB The fruit all branch from more or less the same point. See red arrow.

The black fruit

Thanks to Wikipedia for text and information: https://creativecommons.org/licenses/by-sa/3.0/