Euphorbia herbstii (syn. Chamaesyce herbstii)[1] is a rare species of flowering plant in the family Euphorbiaceae known by the common name Herbst's sandmat. It is endemic to Oʻahu, Hawaii, where it is rapidly disappearing.[2] Like other Hawaiian euphorbs, this plant is known locally as ʻakoko. It is a federally listed endangered species of the United States.

Euphorbia herbstii

Critically Imperiled  (NatureServe)
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Malpighiales
Family: Euphorbiaceae
Genus: Euphorbia
Species:
E. herbstii
Binomial name
Euphorbia herbstii
(W.L.Wagner) Oudejans
Synonyms

Euphorbia clusiifolia Hook. & Arn.
Euphorbia forbesii Sherff
Chamaesyce herbstii W.L.Wagner
Chamaesyce forbesii (Sherff) Croizat & O.Deg.
Chamaesyce clusiifolia (Hook. & Arn.) Arthur
Anisophyllum nodosum Klotzsch & Garcke

This plant is usually a tree which can grow up to 8 meters tall. The leaf blades are long and narrow, and the branches bleed a milky sap. The inflorescence is a cluster of cyathia.

This species is known from perhaps four populations[3] in mesic forests on the Waiʻanae Range.[2] Since the year 2000 the plant has undergone a severe decline, with populations extirpated and remaining ones becoming smaller.[2] The exact number of remaining plants is unknown because each survey tallies fewer individuals, while more have been planted in appropriate habitat.[2]

Threats to the species include feral pigs, which uproot and trample vegetation, leading to loss of plant cover and root networks, which then leads to erosion.[2] They pick up the seeds of invasive plant species and transport them to new habitats.[2] Fences have been erected in critical areas to exclude the pigs.[2] Non-native plants affecting the euphorb include silky oak (Grevillea robusta), corky-stem passionflower (Passiflora suberosa), and strawberry guava (Psidium littorale).[2]

References

edit
  1. ^ "Euphorbia herbstii". Germplasm Resources Information Network. Agricultural Research Service, United States Department of Agriculture. Retrieved 25 January 2018.
  2. ^ a b c d e f g h USFWS. Chamaesyce herbstii Five Year Review. August 2, 2007.
  3. ^ The Nature Conservancy