Loranthus

''Loranthus'' is a genus of parasitic plants that grow on the branches of woody trees. It belongs to the family Loranthaceae, the showy mistletoe family. In most earlier systematic treatments it contains all mistletoe species with bisexual flowers, though some species have reversed to unisexual flowers. Other treatments restrict the genus to a few species. The systematic situation of ''Loranthus'' is not entirely clear.

The generic name in botanical Latin means strap-flower, in reference to the shape of the petals.

Taxonomy

The taxonomic history of the generic name ''Loranthus'' is complicated. In 1753, Carl Linnaeus used the name ''Loranthus'' for a genus of one species, ''Loranthus americanus'', which was thus the type species. He later added other species, including ''Loranthus scurrula'' in 1762, a species he had previously placed in a separate genus, ''Scurrula'', and ''Loranthus europaeus'' in 1763, a name first used by Jacquin in 1762. However, ''Loranthus americanus'' has been included in ''Psittacanthus'' since that genus was first erected in 1830. Application of priority as set out in the International Code of Nomenclature for algae, fungi, and plants requires the name ''Loranthus'' to be used instead of ''Psittacanthus'', with a different genus name used for the remaining species Linnaeus placed in ''Loranthus''. To avoid altering established usage, the International Botanical Congress of 1930 decided to conserve ''Loranthus'' L. (1762), with the type species ''Loranthus scurrula'', over ''Loranthus'' L. (1753). However, when ''Loranthus'' in this sense was split further, ''Loranthus scurrula'' was placed in the revived genus ''Scurrula''. The conservation decision in 1930 meant that ''Loranthus'' should be used instead of ''Scurrula'', and a different name used for ''Scurrula''. Again to avoid altering established usage, a proposal was agreed in 1964 to conserve ''Loranthus'' Jacq. (1762), with the type species ''Loranthus europaeus'', over ''Loranthus'' L. (1753).

Species

The number of species recognized in the genus ''Loranthus'' has varied widely. At one time it included almost all mistletoes. It was then split into many genera, leaving only '' L. europaeus'' from Europe eastwards and '' L. odoratus'' from tropical Asia. The ''Flora of China'' lists six species native to China (three endemic), stating that there are about ten species in total.
Species recognized are:
*'' Loranthus delavayi'' Tiegh.
*'' Loranthus europaeus'' Jacq.
*'' Loranthus guizhouensis'' H.X.Qiu
*'' Loranthus kaoi'' (J.M. Chao) H.S.Kiu
*'' Loranthus lambertianus'' Schult.f.
*'' Loranthus longiflorus'' Desr.
*'' Loranthus macrantherus'' (Eichler) Hemsl.
*'' Loranthus pseudo-odoratus'' Lingelsh.
*'' Loranthus pulverulentus'' Wall.
*'' Loranthus tanakae'' Franch. & Sav.

Ecology

Some species of ''Loranthus'', in the broad sense, are parasites on cultivated trees; for example, they occur in Kerala and Uttarakhand India on mango trees (''Mangifera indica''), sapota trees (''Manilkara zapota'') and poplar trees.Kumari, S., Singh, A.K., Kumar, S., and Shah, V.K. (2020). A Hidden Problem: ''Loranthus falcatus'' L. & Loranthus ''parasitica'' L. for Horticulture Crops. ''Agriculture and food eNewsletter'', 2(5):719-721. https://www.researchgate.net/publication/341182673_A_Hidden_Problem_Loranthus_Falcatus_L_Loranthus_Parasitica_L_for_Horticulture_Crops The majority of the ''Anogeissus latifolia'' trees in the Biligirirangan Hills of Karnataka are infected by ''Loranthus'' species and in Africa, they are pests in cocoa plantations. These plants grow strongly on ageing trees particularly somewhere in the middle of old branches. Once established, they steal minerals and water, as well as block sunlight by covering the encroached place.

The flowers of ''Loranthus europaeus'' are small, green, usually have four to six parts, and may be either unisexual or bisexual. Other species of a broader ''Loranthus'' have very large, showy flowers, with blooms in bright colours. The fruits are berries, usually containing a single seed, that is dispersed by birds.

The floral characteristics indicate that it is ornithophilous in nature and has moderate quantity nectar stored in its perianth tube. The mature buds require external factors like tripping to ensure that they open up. In the absence of this, the buds fall off without opening. Birds help in this process and mature buds eject a cloud of pollens that sticks to the head or beak of the probing bird. The birds seen visiting these flowers in India are Tickell's flowerpecker, purple-rumped sunbird, purple sunbird and spider-hunter.

Culture and religion

According to Pliny the Elder, the Celts considered "mistletoe" a remedy for barrenness in animals and an antidote to poison, and sacred when growing on oak trees. He describes a Celtic ritual sacrifice and banquet at which a druid dressed in white would climb an oak tree to collect mistletoe using a golden sickle.
Modern botanists believe the described species in oak trees was Loranthus europaeus.

This legend is often referred to in the popular ''Asterix'' comic books, where the druid Getafix is often seen collecting mistletoe with a golden sickle.

Modern druids in the Americas may use the native American '' Phoradendron leucarpum'' as well as other mistletoe species.

References

{{Taxonbar, from=Q163517

Loranthaceae
Loranthaceae genera