''Rilaena triangularis'' is a species of the

harvestman The Opiliones (formerly Phalangida) are an order of arachnids, colloquially known as harvestmen, harvesters, harvest spiders, or daddy longlegs (see below). , over 6,650 species of harvestmen have been discovered worldwide, although the total n ...

family

Phalangiidae The Phalangiidae are a family of harvestmen with about 380 known species. The best known is ''Phalangium opilio''. ''Dicranopalpus ramosus'' is a common introduced species in Europe. It is not to be confused with the harvestman family Phalangodi ...

.Raspotnig, G., Schaider, M., Föttinger, P., Leutgeb, V., & Komposch, C. (2015). Benzoquinones from scent glands of phalangiid harvestmen (Arachnida, Opiliones, Eupnoi): a lesson from Rilaena triangularis. Chemoecology, 25(2), 63–72. https://doi.org/10.1007/s00049-014-0177-y It is sometimes considered to be in the genus '' Paraplatybunus'', in the subfamily Platybuninae.

Description

''Rilaena triangularis'' is a harvestman that lives across Europe. This species was first described by

Johann Friedrich Wilhelm Herbst Johann Friedrich Wilhelm Herbst (1 November 1743 – 5 November 1807) was a German natural history, naturalist and entomologist from Petershagen, Minden-Ravensberg. He served as a chaplain in the Prussian army. His marriage in Berlin, 1770, with E ...

in 1799, initially as ''Phalangium triangularis''. It was later renamed through recombination.

Chemical defense

When disturbed, ''Rilaena triangularis'' emits a strong-smelling secretion as a

chemical defense Chemical defense is a strategy employed by many organisms to avoid consumption by producing toxic or repellent metabolites or chemical warnings which incite defensive behavioral changes. The production of defensive chemicals occurs in plants, fung ...

. This fluid contains

1,4-benzoquinone 1,4-Benzoquinone, commonly known as ''para''-quinone, is a chemical compound with the chemical formula, formula C6H4O2. In a pure state, it forms bright-yellow crystals with a characteristic irritating odor, resembling that of chlorine, bleach, ...

1,4-naphthoquinone 1,4-Naphthoquinone or para-naphthoquinone is a quinone derived from naphthalene. It forms volatile yellow triclinic crystals and has a sharp odor similar to benzoquinone. It is almost insoluble in cold water, slightly soluble in petroleum ethe ...

and

caprylic acid Caprylic acid (), also known under the systematic name octanoic acid or C8 Acid, is a saturated fatty acid, medium-chain fatty acid (MCFA). It has the structural formula , and is a colorless oily liquid that is minimally soluble in water with ...

Range

Occurrences of ''Rilaena triangularis'' have been recorded and aggregated in

GBIF The Global Biodiversity Information Facility (GBIF) is an international organisation that focuses on making scientific data on biodiversity available via the Internet using web services. The data are provided by many institutions from around the ...

across

Europe Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east ...

, with the exception of Spain and Portugal. It has also been observed in north-west and north-east corners of the United States.

Habitat

The species thrives in

forests A forest is an ecosystem characterized by a dense community of trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological functio ...

, floodplain forests and

fen A fen is a type of peat-accumulating wetland fed by mineral-rich ground or surface water. It is one of the main types of wetland along with marshes, swamps, and bogs. Bogs and fens, both peat-forming ecosystems, are also known as mires ...

s.Komposch C, Gruber J. Die Weberknechte Österreichs (Arachnida: Opiliones) Denisia. 2004;14:485–534.

References

Harvestmen Articles containing video clips Animals described in 1799 {{Opiliones-stub