Colletia

Colletia is a genus of flowering plants in the family Rhamnaceae, with five species of spiny shrubs. All species of this genus are native to southern South America. They are non-legume nitrogen fixers.

Taxonomy

Colletia comprises the following species:^[1]^[2]

Colletia hystrix Clos - pink crucifixion thorn
Colletia paradoxa (Spreng.) Escal. - crucifixion thorn, thorn of the cross, anchor plant
Colletia spartioides Bertero ex Colla
Colletia spinosissima J.F.Gmel.
Colletia ulicina Gillies & Hook.

The status of the following species and hybrids is unresolved:^[1]

Celtis iguanaea (Jacq.) Sarg. (as Colletia iguanaea Scop.)
Discaria americana Gillies & Hook. (as Colletia longispina Hook. & Arn. and C. longissima Steud.)
Retanilla stricta Hook. & Arn. (as Colletia tetrandra Clos)
Retanilla trinervia (Gillies & Hook.) Hook. & Arn. (as Colletia treba Bertero ex Colla)
Rhamnus diffusa Clos (as Colletia maytenoides Griseb.)
Scutia spicata (Humb. & Bonpl. ex Schult.) Weberb. (as Colletia spicata Humb. & Bonpl. ex Schult.)
Trevoa campanulata (Phil.) Reiche (as Colletia campanulata Phil.)
Trevoa quinquenervia Gillies & Hook. (as Colletia tralhuen Bertero ex Colla)

^ ^a ^b "The Plant List entry for Colletia". The Plant List, v.1.1. Royal Botanic Gardens, Kew and the Missouri Botanical Garden. September 2013. Retrieved 14 December 2020.
^ Govaerts R. "Colletia Comm. ex Juss.". Plants of the World Online. Board of Trustees of the Royal Botanic Gardens, Kew. Retrieved 15 December 2020.