Clymenia (plant)

''Clymenia'' is a small genus of flowering plants in the family Rutaceae with two species. The genus is often included in ''Citrus''.

Description

''Clymenia'' forms a shrub or small tree, free of spines. Leaves feature a short, narrow petiole, which sets them apart from most other citrus, especially the papedas native to the same general area. ''Clymenia'' fruits are a small hesperidium, very similar to a citrus fruit. Sweet and lemony in flavor, the tangerine-sized fruits are highly segmented, with yellow pulp, and a leathery rind, similar to a true citrus fruit. They contain a large number of polyembryonic seeds. The fruit are eaten by the Bismarck islanders, who call it ''a-mulis'' ( Namatanai).

Native to a handful of locations on Papua New Guinea and nearby islets, including New Ireland, New Britain and the Admiralty Islands, ''Clymenia'' is far more tropical than other citrus, and even in subtropical parts of the United States, it can only be grown in a greenhouse. Specimens thrived in greenhouses in Riverside, California, but perished when planted out in the arid climate. They are locally cultivated in indigenous villages, but have never been commercially cultivated.

Taxonomy

Cultivated locally for its sweet fruits on a handful of southwestern Pacific islands, ''Clymenia'' was originally considered an obscure citrus hybrid. Botanist Tyôzaburô Tanaka noted that ''Clymenia'' would hybridize with a few other citrus plants (notably kumquats), but otherwise was generally different from other citrus in many aspects of its appearance. Botanist Walter Tennyson Swingle proposed moving ''Clymenia'' out of ''Citrus'', circumscribing the genus in 1939, naming it after a figure from Greek mythology, Clymene, an Orchomenian princess who was the mother of Atalanta. Swingle assumed that ''Clymenia'' and citrus evolved from a single common ancestor. In 2000, Berhow suggested that a close relationship existed between ''Clymenia'' and kumquats and that it might be a Citrofortunella, a kumquat hybrid with another citrus.

Recent genomic analysis has shed new light on the phylogeny of ''Clemenia'', potentially clarifying questions of its taxonomy. ''Clymenia polyandra'' was found to be completely homozygous, proving it to be a distinct species and not a kumquat hybrid. ''Clymenia'' clusters within the genus ''Citrus'' in a clade with the Australian and New Guinean limes, which though formerly placed in genera ''Eremocitrus'' and ''Microcitrus'' are now considered members of ''Citrus''. Because excluding ''Clymenia'' would make ''Citrus'' paraphyletic, the ''Clymenia'' species may likewise belong in ''Citrus'', with ''Clymenia'' relegated to the status of a subgenus. It is included in ''Citrus'' in a 2021 classification of the family Rutaceae.

Species

Species included in the genus:Benjamin C. Stone (1985). "New and noteworthy palotropical species of Rutaceae", ''Proceedings of The Academy of Natural Sciences of Philadelphia'', vol. 137, pp. 213–228
*'' Clymenia platypoda'' B.C.Stone
*'' Clymenia polyandra'' (Tanaka) Swingle

References

External links

Pictures of Clymenia
in Papua New Guinea.

{{Taxonbar, from=Q5137103

Aurantioideae
Aurantioideae genera
Edible fruits