Dypsis.
Plants of the World Online has Chrysalidocarpus as the genus name.
On World Flora Online and in Australia it is Dypsis.
Kew recognises 57 species while others have up to around 140.
This difference is explained by two name changes.
Previously, in the sub-tribe Dypsidinae the Chrysalidocarpus genus was changed to Dypsis.
Recently, as a result of molecular analysis Dypsis was split into 3.
Two of these are the old Chrysalidocarpus and Dypsis genera.
In the process a lot of old Dypsis species were moved into Chrysalidocarpus.
This reduced the species in the new Dypsis from around 173 to around 57.
Some websites still have the old larger Dypsis genus.
Because of this, when reading genus descriptions it is necessary to see which genus they are referring to.
Check the number of species or the date as there are marked differences in descriptions of the two.
Almost all the 57 species are from Madagascar or near by.
They are solitary or clumping palms up to around 12 m high.
Stems occasionally branch and some produce offsets.
Ring scars from fallen leaves are close to spread apart.
There are no spines.
The slender arching leaves are up to 2.5 or 3 m long including a long petiole.
Petiole and midrib may be green or yellow.
Pinnate leaves can have up to 60 leaflets each side of the midrib.
The leaflets may be curved and the edges are folded back (reduplicate).
The upper surface of the petiole has a groove with sharp edges.
Leaf bases may form a prominent crown shaft.
Leaves may have rust-coloured hairs or scales when young.
Inflorescences, branching 3 or 4 times are below or among the leaf bases.
The peduncle has a basal bract (prophyll) up to 1 m long.
Further up the peduncle is a smaller peduncular bract.
The primary branches have a smaller bract at their base.
Ultimate branches are pendulous and have dense flowers in groups of 3.
Groups have 1 female with a male each side.
Male flowers have 3 overlapping sepals and 3 petals that don’t overlap.
There are 6 stamens and an infertile columnar or conical ovary or pistillode.
Female flowers have 3 sepals and 3 petals, all free and overlapping.
The ovary has 1 ovule and 3 stigma lobes.
The smallish fruit have the sepals and stigmas attached.
They mature to yellow or purplish-black.
They have a fibrous layer around the seed.
J.F.
