Zamioculcas zamiifolia
species

Taxonomical history
(draft)

Annotation: Well, if these communications can be verified, this would leave one interesting question to be answered: What about the other taxon with thick, ovoid leaflets that is being traded as "Zamioculcas zamiifolia" in hundreds of thousands worldwide ?

   In my opinion, there is no doubt that there are indeed two different taxa (see below) that actually show differences that are similar to those described by PETER. However, with Z. zamiifolia being the only valid name in the genus at present, I will continue to use that name on these pages when referring to the thick-leaved plant with inflated leaf bases. The other taxon is referred to as "different" or "other" Zamioculcas. There will be no speculations about the taxonomical rank of either of these taxa on these pages at this time.

   If you happen to have an image of this painting (plate 1408 from Loddiges) or of plate 5985 by HOOKER in Curtis' Botanical Magazine (mentioned by ENGLER and PETER), I'd be most grateful to see it and/or to get permission to present it here.

Second Taxon
in Zamioculcas?

   PETER's description of a second species - although not valid taxonomically - is still interesting. Within a week after the first draft of this page (describing my own observation of a "different" Zamioculcas in the Giardino dei Semplici in Florence, Italy) had gone online, I received email messages from two plant lovers on that very issue, confirming that they grow both "forms" and that the differences were evident.
Read about my observations on this page 

See annotation above.

   The National Botanic Garden of Belgium in Meise (near Brussels) has a second taxon as well in their Living Plants Collections (but not the one I'm referring to above):

Annotation: This is the only reference to a variegated Zz that I have found so far. No image available yet.

Etymology

   The name Zamioculcas derives from Zamia (a genus of the cycad family Zamiaceae) and qolqas (Arabic for taro, i.e. the tropical crop Colocasia esculenta. The name of this aroid genus, Colocasia, contains the same stem).

   The reference to Zamia relates to a certain similarity with the pinnate leaves of some members of this Cycad genus that have dark green, ± xeromorph leaflets with a shape reminding of those of Zz. This superficial resemblance is repeated in the epithet zamiifolia (=with Zamia's leaves).

   Regardless of floral differences (Zamioculcas is a monocot angiosperm, Zamia is a cycad gymnosperm), Zamia -like virtually all Cycads- has a rosette of leaves on top of a normally monopodious wooden stem (and not alternate leaves from a tuberous underground rhizome like Zz); Zamia's leaflets are parallel-veined (Zz: reticulate), and no Cycad has either the quite conspicuous inflated leaf bases or the 'knee' in the leaf petiole of Zamioculcas.

   According to IPNI (International Plant Names Index), the epithets zamiifolium, zamiaefolia, or zamioides are also found in the following (mostly outdated) combinations (results © the Plant Names Project, quoted in full):

   An english vernacular name for Zamioculcas is "Aroid Palm"; however, Zz is not a tree (it does not even have a wooden stem), which is a very distinctive character of (most) palms. (After all, you wouldn't call a fern or a member of the Apiaceae a "palm", only because it has pinnate leaves, would you?)

   The (quasi) common English name "Zz plant" has no connection with "ZZ Top" (a music group), but is, of course, an abbreviation of the scientific name. (Annotation:  ;-)

Other Literature references

Zamioculcas SCHOTT (1856)
Tribe Zamioculcadeae SCHOTT ex ENGL.,
- Nova Acta Acad. Leopold-Carol. 39: 141. 1876 (Zamioculcaseae).

ENGLER, A. (1881b). Über Reproduction von Zamioculcas loddigesii DECNE. aus ihren Fiederblättchen. - Bot. Jahrb. Syst. 1: 189-190.

OBERMEYER, A. A. & R. G. STREY. (1969). Zamioculcas zamiifolia. - Kongel. Danske Vidensk. Selsk. Skr., Naturvidensk. Math. Afd., ser. 7: 40.

SORAN, V., B. SMITH & R. VINTILA. (1973). Absorption spectra of Zamioculcas boivinii chloroplasts recorded in vivio and after isolation by micro-spectrophotometric method. - Z Pflanzenphysiol) 1973, 69 (2): 100-108.
(Note: Zamioculcas boivinii is a synonym of Gonatopus boivinii; see )

TRAGER, JN. (1982). Cacti and succulents for the amateur. - Cact. Succ. J. (U.S.A.) 54(4): 160-161 (1982)- illus. - notes: Zamioculcas zamifolia.

KAPLAN, D. R. (1983). The development of palm leaves Zamioculcas zamiifolia. - Scientific American July 1983. v. 249 (1) (Sci Am): 98-105. ill. 

MAYO, S. (1985): Araceae. - In: POLHILL, R. (ed.): Flora of Tropical East Africa.

TROFIMOVA, I. A. (1985). (Transl. Title:) Biomorphology and development of Zamioculcas in greenhouse conditions. - Biulleten' Glavnogo botanicheskogo sada. (Biull Gl Bot Sada) 1985. (137): 79-83. ill.

BARABÉ, D. & S. FORGET. (1988b). Anatomie des fleurs fertiles et steriles de Zamioculcas (Araceae). - Bull. Mus. Natl. Hist. Nat., Paris, Adansonia 10(4): 411-419.

NEWTON, L. (1997). Zamioculcas zamiifolia. - Ballya 4(3): 68-69 (1997)

HESSE, M., J. BOGNER, H. HALBRITTER, M. WEBER. (2001): Palynology of the perigoniate Aroideae: Zamioculcas, Gonatopus and Stylochaeton (Araceae) - In: CIVEYREL, L., C. A. FURNESS, G. El GHAZALY (ed.): The Role of Palynology in Phylogeny and Systematics. Pollen symposium. XVI International Palynological Congress, Saint Louis 1999. - Grana 40(1-2): 26 - 34