''Silaum silaus'', commonly known as pepper-saxifrage, is a

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wid ...

plant in the family Apiaceae (Umbelliferae) (the carrot family) found across south-eastern, central, and western Europe, including the British Isles. It grows in damp grasslands on neutral soils.

Description

''Silaum silaus'' is an erect,

glabrous Glabrousness (from the Latin '' glaber'' meaning "bald", "hairless", "shaved", "smooth") is the technical term for a lack of hair, down, setae, trichomes or other such covering. A glabrous surface may be a natural characteristic of all or part of ...

umbellifer Apiaceae or Umbelliferae is a family of mostly aromatic flowering plants named after the type genus '' Apium'' and commonly known as the celery, carrot or parsley family, or simply as umbellifers. It is the 16th-largest family of flowering plant ...

with woody, stout and cylindrical tap roots, which are hot and

aromatic In chemistry, aromaticity is a chemical property of cyclic ( ring-shaped), ''typically'' planar (flat) molecular structures with pi bonds in resonance (those containing delocalized electrons) that gives increased stability compared to satur ...

. ''S. silaus'' has dark grey or black petioles at the top; petiole remains are found at the bottom of the stem, which is solid and

striate In geology, a striation is a groove, created by a geological process, on the surface of a rock or a mineral. In structural geology, striations are linear furrows, or linear marks, generated from fault movement. The striation's direction revea ...

. Its

umbels In botany, an umbel is an inflorescence that consists of a number of short flower stalks (called pedicels) that spread from a common point, somewhat like umbrella ribs. The word was coined in botanical usage in the 1590s, from Latin ''umbella'' " ...

are 2–6 cm in diameter, are

terminal Terminal may refer to: Computing Hardware * Terminal (electronics), a device for joining electrical circuits together * Terminal (telecommunication), a device communicating over a line * Computer terminal, a set of primary input and output dev ...

or axillary, and compound, with 4 to 15 angled rays of 1–3 cm; the peduncle is larger than the rays, and both are

papillose This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...

. The flowers are mostly

hermaphroditic In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many taxonomic groups of animals (mostly invertebrates) do not have s ...

. ''Silaum silaus'' has 2–4-

pinnate Pinnation (also called pennation) is the arrangement of feather-like or multi-divided features arising from both sides of a common axis. Pinnation occurs in biological morphology, in crystals, such as some forms of ice or metal crystals, and in ...

leaves, which have a triangular and

lanceolate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular ...

outline, a long petiole and the primary divisions are long-stalked. Segments are 10–15 mm long, shaped from lanceolate to linear, the ends are

acuminate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular ...

or obtuse and mucronate, the leaves are finely

serrulate The following is a list of terms which are used to describe leaf morphology in the description and taxonomy of plants. Leaves may be simple (a single leaf blade or lamina) or compound (with several leaflets). The edge of the leaf may be regular o ...

, with a prominent

midrib This glossary of botanical terms is a list of definitions of terms and concepts relevant to botany and plants in general. Terms of plant morphology are included here as well as at the more specific Glossary of plant morphology and Glossary o ...

; the apex is often reddish in colour. There are 1-

upper

cauline A leaf ( : leaves) is any of the principal appendages of a vascular plant stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", while the leaves, ste ...

leaves present, which are either simple or reduced to a sheath; there is no petiole and the

cotyledons A cotyledon (; ; ; , gen. (), ) is a significant part of the embryo within the seed of a plant, and is defined as "the embryonic leaf in seed-bearing plants, one or more of which are the first to appear from a germinating seed." The num ...

are tapered at the base. There are 0–3

bracts In botany Botany, also called , plant biology or phytology, is the science of plant life and a branch of biology. A botanist, plant scientist or phytologist is a scientist who specialises in this field. The term "botany" comes from the An ...

and 5–11

bracteoles In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves. They may be smaller, larger, or o ...

; the

pedicels In botany, a pedicel is a stem that attaches a single flower to the inflorescence. Such inflorescences are described as ''pedicellate''. Description Pedicel refers to a structure connecting a single flower to its inflorescence. In the absenc ...

are linear-lanceolate with scarious margins. The flowers are yellowish and 1.5 mm across, with absent sepals, and the styles form a stylopodium. The fruits are 4–5 mm in size, oblong-ovoid, and are rarely compressed. The

commissure A commissure () is the location at which two objects abut or are joined. The term is used especially in the fields of anatomy and biology. * The most common usage of the term refers to the brain's commissures, of which there are five. Such a commi ...

is broad, the mericarps are prominent with slender ridges and lateral forming narrow wings; a carpophore is present. There are numerous vittae, with stout

of 2–3 mm in size, and the stigmas are

capitate The capitate bone is a bone in the human wrist found in the center of the carpal bone region, located at the distal end of the radius and ulna bones. It articulates with the third metacarpal bone (the middle finger) and forms the third carpomet ...

Taxonomy

''Silaum silaus'' was one of the many species described by

Carl Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his Nobility#Ennoblement, ennoblement in 1761 as Carl von Linné#Blunt, Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalise ...

in volume 1 of the 1753 edition of his ' as ''Peucedanum silaus''. It was given its current binomial name in 1915 by Swiss botanists

Hans Schinz Hans Schinz (6 December 1858 – 30 October 1941) was a Swiss explorer and botanist who was a native of Zürich. In 1884 he participated in an exploratory expedition to German Southwest Africa that was organized by German merchant Adolf Lüde ...

and Albert Thellung in 1915. The

etymology Etymology ()The New Oxford Dictionary of English (1998) – p. 633 "Etymology /ˌɛtɪˈmɒlədʒi/ the study of the class in words and the way their meanings have changed throughout time". is the study of the history of the Phonological chan ...

of the genus name ''Silaum ''is uncertain, although it may refer to the mountainous plateau

La Sila La Sila, also simply Sila, is the name of the mountainous plateau and historic region located in Calabria, southern Italy. The Sila National Park is known to have the purest air in Europe. Geography The Sila occupies part of the provinces of Co ...

in southern

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

. Another possible explanation is that ''Silaum'' may be derived from the yellow ochre, related to the colour of the plant's flowers. ''Silaus'' is an old generic name used by

Pliny Pliny may refer to: People * Pliny the Elder (23–79 CE), ancient Roman nobleman, scientist, historian, and author of ''Naturalis Historia'' (''Pliny's Natural History'') * Pliny the Younger (died 113), ancient Roman statesman, orator, w ...

. ''Silaum silaus'' bears the common name pepper-saxifrage (with or without hyphenation) despite being neither a

saxifrage ''Saxifraga'' is the largest genus in the family Saxifragaceae, containing about 465 species of holarctic perennial plants, known as saxifrages or rockfoils. The Latin word ''saxifraga'' means literally "stone-breaker", from Latin ' ("rock" or " ...

nor peppery in taste.

Distribution and habitat

''Silaum silaus'' is found in western, central and south-eastern

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located entirel ...

(including

Great Britain Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It i ...

), north to the

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

and Sweden but is absent from

Portugal Portugal, officially the Portuguese Republic ( pt, República Portuguesa, links=yes ), is a country whose mainland is located on the Iberian Peninsula of Southwestern Europe, and whose territory also includes the Atlantic archipelagos of ...

. In Great Britain, it is found mainly south of the far south of

Scotland Scotland (, ) is a Countries of the United Kingdom, country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a Anglo-Scottish border, border with England to the southeast ...

. The species is listed as an invasive species in

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of Denmark , establish ...

. ''Silaum silaus'' grows in a wide variety of habitats, generally preferring those with damper soils. Specifically, ''S. silaus'' can be found in unimproved neutral grassland, railway and road verges and

meadows A meadow ( ) is an open habitat, or field, vegetated by grasses, herbs, and other non-woody plants. Trees or shrubs may sparsely populate meadows, as long as these areas maintain an open character. Meadows may be naturally occurring or artificia ...

(hay, water and lowland meadows); it is also occasionally found on chalk downs and vegetated shingle.

Ecology

''Silaum silaus'' is an indicator of agriculturally unimproved meadows, and is part of a group (in the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...

) of flowering plants specially associated with neutral grassland associated with low-nutrient regimes. This group is declining in the UK due to agricultural improvement, diffuse pollution and habitat fragmentation and hence ''S. silaus'' is on the

United Kingdom Biodiversity Action Plan The United Kingdom Biodiversity Action Plan or (UK BAP) was the UK government's response to the Convention on Biological Diversity, opened for signature at the Rio Earth Summit in 1992. The UK was the first country to produce a national Biodivers ...

. At least three species of

moth Moths are a paraphyletic group of insects that includes all members of the order Lepidoptera that are not butterflies, with moths making up the vast majority of the order. There are thought to be approximately 160,000 species of moth, many of w ...

larvae in the UK use the plant as a food source – '' Sitochroa palealis'', '' Agonopterix ciliella'' and '' Agonopterix yeatiana''. ''Silaum silaus'' fruit has been identified from substage III of the

Hoxnian interglacial __NOTOC__ The Hoxnian Stage was a middle Pleistocene stage (Pleistocene from million to 11,700 years BP) of the geological history of the British Isles. It was an interglacial which preceded the Wolstonian Stage and followed the Anglian Stage. I ...

period (a stage in the middle

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...

) in the British Isles.

Uses

''Silaum silaus'' is listed in John Parkinson's 1640 work ''Theatrum Botanicum'' as being able to soothe "frets" in infants.

References

External links

* {{Taxonbar, from=Q1520956 Flora of Europe Plants described in 1753 Taxa named by Carl Linnaeus silaus