The following blog was written by Chris Knowles, a digitiser in the Herbarium.
Since 2021 we have increased our digitisation capacity with the goal of getting to 1 million specimens imaged by Autumn 2024. Each digitiser is assigned a family of plants to work through. This series of blogs will spotlight the families that have been completed by a member of the team.
The custard apple family, Annonaceae consists of flowering trees, shrubs and woody climbing plants. They are mostly found in tropical and subtropical areas across countries in the Americas, Africa and Asia.
Some of the 2,400 species are considered to be valuable for either their wood, fruit or ornamental character. Although some custard apples produce poisonous fruits, others like the Soursop (Annona muricata) are highly prized as foods, flavourings and medicines.
Our collections at Edinburgh
The herbarium at RBGE has a total of 4,333 specimens, of which 215 are type specimens. Type specimens are hugely important to taxonomists as they are the plant specimens used to create the description of a species. The name, description and specimen are all needed to define a species scientifically and are continually returned to as the definitive reference point.
2,413 specimens had previously been digitised in this family but getting the remaining 1,920 databased and imaged for the online catalogue was another great milestone for the digitisation team.
Specimens of Annonaceae can be searched on our online catalogue here.
Top 5 regions
The collections here come from 22 different geographical herbarium regions within the distribution area for this family, which is very representative of the total worldwide distribution of this species.
| No. of Specimens | Herbarium Filing Region |
| 904 | Malay Islands |
| 682 | Indo-China |
| 516 | Malay Peninsula |
| 431 | Tropical Africa |
| 379 | East Tropical South America |
Top 5 Genera
Of the currently recognised 129 genera in the Annonaceae family, 103 are represented in the RBGE collection.
| No. of Specimens | Genus |
| 535 | Polyalthia |
| 291 | Uvaria |
| 269 | Xylopia |
| 244 | Goniothalamus |
| 241 | Annona |
Interesting specimens
While working through the collection, the digitisers often come across interesting specimens that stand out. For example, this specimen of Orophea polycarpa from Myanmar was collected by Captain R.W.MacGregor in 1910, and is accompanied by beautifully detailed illustrations of the tree’s flowering parts.
Other illustrations attached to specimens in the Annonaceae. Family can be seen here.