Silaum

Silaum
A botanical illustration of Silaum silaus
Scientific classification
Kingdom: Plantae
(unranked): Angiosperms
(unranked): Eudicots
(unranked): Asterids
Order: Apiales
Family: Apiaceae
Genus: Silaum
Mill.

Silaum is a genus of flowering plants in the carrot/parsley family, Apiaceae. There are currently ten species placed into the genus, a list of which is provided below.[1]

Taxonomy and naming

Silaum was first formally described in 1754 by the Scottish botanist in charge of the Chelsea Physic Garden, Philip Miller; this description was published in his own reference series, The Gardeners Dictionary (abr., ed. 4 (1754)).[2] The etymology of Silaum was not explicitly offered by Miller, who applied a plant name used by Pliny,[3] though it may refer to the mountainous plateau La Sila in southern Italy.[4]

Description

Plants in the genus Silaum have umbels which are characteristic of plants in the Apiaceae family (they are umbelliferous, "umbel-bearing"); the umbels in Silaus species tend to lack bracts.[2] Silaus species also tend to have a few umbellules (secondary umbels of compound umbels), and these umbellules have several small bracts called bractlets.[2] Remains of dead leaves can often be found at the base of the plant; plants in Silaum are richly branched.[2]

The fruits of Silaum species have a carpophore,[2] a supporting slender stalk for each half of a gape or burst open (dehisced) fruit[5] - these are common throughout the Apiaceae family; the carpophore is thread or filament-shaped (filiform).[2] In addition, Silaum fruits are elongated, divided and not flattened.[2] The mericarps (one carpel of umbelliferous fruit)[6] have acute edges and five, rather low ridges.[2] Plants in Silaus also have an oil tube in the fruit, called a vitta[2][7] - there is one vitta per every ridge of furrow (a vallecula), but are indistinct at maturity.[2] The petals that surround the flowers are yellow.[2]

Species

The Global Biodiversity Information Facility (GBIF) lists ten species that are currently placed in the genus Silaum:[1]

References

  1. 1.0 1.1 "Silaum Mill.". GBIF Backbone Taxonomy. GBIF.org. Archived from the original on 27 December 2013. Retrieved 27 December 2013.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 2.10 Fröberg, Lars. "Silaum". Apiaceae for Flora Nordica. Flora Nordica. Archived from the original on 27 December 2013. Retrieved 27 December 2013.
  3. Pliny the Elder, Naturalis Historia, Book XXVI, chapter lvi, § 88, the sole mention of Silaus: silaus nascitur glariosis et perennibus rivis, cubitalis apii similitudine...
  4. Gledhill, D. (2008). The Names of Plants (4 ed.). Cambridge University Press. pp. 353–. ISBN 9780521866453. Retrieved 29 October 2013.
  5. "definition of carpophore". TheFreeDictionary.com. Retrieved 30 December 2013.
  6. "definition of Mericarp". TheFreeDictionary.com. Retrieved 30 December 2013.
  7. "definition of vitta". TheFreeDictionary.com. Retrieved 30 December 2013.