Genus honouring James William Harris (1860-1920), Irish botanist, Superintendent of Public Gardens and Plantations of Jamaica (see portrait above, public domain).
A genus of often treelike, mostly shrubby plants, with more or less slender, branched but not segmented branches, not forming aerial roots, sometimes erect, curved, decumbent, often prostrate but using the surrounding vegetation to remain erect, becoming woody at the base. Areoles tomentose. Spines of variable size, the lower usually longer and sturdier, continuing their growth on older areoles and increasing in number with age.
Flowers nocturnal, often self-fertile, funnel-shaped, nice-smelling or not (H. taetra), bearing scaly trichomes, white, pollinated by Sphingideae (Pseudosphinx tetrio) and bats (Monophyllus redmani and Phyllonycteris poeyi), also by supposed anemophily (H. portoricensis, Rojas-Sandoval & Melendez-Ackerman 2009; Rojas-Sandoval 2012). Fruits globose to egg-shaped, scaly or spiny, yellow or orange, indehiscent (not opening) in the subgenus Harrisia, or red
and dehiscent (splitting) in the subgenus Eriocereus, with edible white pulp containing numerous seeds (from 100 up to more than 1000), floral remains persistent when ripe. Seeds large, black or brown, roughly oblong, with a scaly appearance. Fruits consumed accordingly to regions by lizards, mice, coatis, foxes, tapirs (Tapirus terrestris). The dispersal of seeds is probably ensured by them, but more often by birds and bats.
The genus Harrisia grows usually in the shade among grasses, bushes and shrubs, in spiny forests with a dry season, in matorral, from sea level on coastal mounds (H. fragrans), mogotes (H. earlei), stacks (H. taetra) up to about 3000 m in altitude (H. tetracantha), in cracks of limestone rocks, usually together with other cacti. The subgenus Harrisia is found in the Caribbean region and in Florida, while the subgenus Eriocereus has a large disjunction, and is present from southern Brazil, in Uruguay, Paraguay, Argentina and Bolivia, then in the Northeast of Brazil (H. adscendens).
Argentina (Buenos Aires, Catamarca, Chaco, Cordoba, Corrientes, Entre Rios, Formosa, Jujuy, Salta, Santa Fe, Santiago del Estero, Tucuman), Bahamas, Bolivia (Chuquisaca, Cochabamba, Potosi, Santa Cruz, Tarija), Brazil (Alagoas, Bahia, Ceara, Mato Grosso do Sul, Paraiba, Piaui, Pernambuco, Sergipe), Cuba (Camaguey, Granma, Guantanamo, Holguin, Oriente, Pinar del Rio, Santiago de Cuba), Haiti, Honduras (Islands del Cisne), Cayman Islands, Jamaica, Paraguay (Alto Paraguay, Boqueron, Central, Concepcion, Cordillera, Guaira, Itapua, Paraguari, Presidente Hayes, San Pedro),Puerto Rico, Dominican Republic, Uruguay (Rio Negro), USA (Florida). Naturalized in South Africa, Australia and Hawaii.
Currently 18 species recognised in this work + one subspecies and a supposed hybrid (according to Franck, 2012):
– Harrisia aboriginum* Small 1920
– Harrisia adscendens* (Gurke) Britton & Rose 1920
– Harrisia (Eriocereus) bonplandii* (Parm.) Britton & Rose 1920 (= H. balansae)
– Harrisia brookii* Britton 1908
– Harrisia caymanensis* Franck 2012
– Harrisia divaricata* (Lam.) Backeb. 1960 (= H. nashli)
– Harrisia earlei* Britton & Rose 1920
– Harrisia eriophora* (Pfeiff.) Britton & Rose 1908
– Harrisia fernowii* Britton 1909 (= H. taylorii)
– Harrisia fragrans* Small 1920 (= H. simpsonii)
– Harrisia gracilis* Britton 1908
– Harrisia (Eriocereus) jusbertii (Rebut, ex K. Schum.) Fric 1932
– Harrisia (Eriocereus) martini* (Labour.) Britton 1917
– Harrisia (Eriocereus) pomanensis* (F.A.C.Weber) Britton & Rose 1920
– Harrisia portoricensis* Britton 1909 (= H. hurstil)
– Harrisia (Eriocereus) regelii* (Weing.) Borg 1937
– Harrisia taetra* Areces 1980
– Harrisia tetracantha* (Labour.) Hunt 1987 ex Roseocereus tephracanthus
– Harrisia (Eriocereus) tortuosa* (J.Forbes ex Otto & A.Dietrich) Britton & Rose 1920
– Harrisia (Eriocereus) tortuosa subsp. uruguayensis* (Osten) J.Lode 2013
References: "TAXONOMY of the CACTACEAE" - ISBN 978-84-617-3723-9 (Vol. 1)