Thapsia (plant)

Thapsia, commonly known as the deadly carrots, is a small genus of poisonous plants in the family Apiaceae. Their center of diversity is around the western Mediterranean, extending into the Atlantic coasts of Portugal and Morocco. Some species are used in traditional medicine.

Description
Species of Thapsia are herbaceous perennials, growing 50 to 200 cm high. The inflorescences are large, regularly distributed umbels. The seeds have four wings, and are the main characteristic of the genus, which is distributed in the Mediterranean, on the Iberian peninsula, and North Africa.

The generic name Thapsia is derived from the Ancient Greek name θαψία (thapsía) for the members of the genus. The Greeks believe it to have originated from ancient Thapsos in Sicily. It has a long history of being used in ancient traditional medicine. Algerians used it as a pain-reliever though they recognized that the plant was deadly to camels. The Greek colony of Cyrene exported a medicinal plant known as silphion, used as a purgative and emetic. Although its exact identity remains contentious today, some historians believe that the plant may have been Thapsia garganica.

Cancer research
The chemical compound thapsigargin has been isolated from Thapsia garganica. A synthetic prodrug of thapsigargin called "G-202" is in preliminary clinical trials for cancer treatment. The active constituent kills tumor cells by destroying their calcium balance. A biotech company called GenSpera, Inc. in San Antonio, TX is studying methods of delivering thapsigargin directly to cancer cells, avoiding damage to other cells in the body of the patient.

Antiviral research
This same chemical compound thapsigargin is now being looked at as an antiviral to use against SARS-coV-2, the coronavirus virus that causes COVID-19. It has not yet reached the clinical trial stage.

Species
About 21 species of Thapsia are currently recognized. It is, however, a complex genus, and some authors may recognize different numbers of species. <!--IPNI is an aggregator, not very reliable The list of species is taken from the IPNI (International Plant Names Index).
 * Thapsia asclepium
 * Thapsia cinerea A.Pujadas
 * Thapsia decussata Lag.
 * Thapsia eliasii
 * Thapsia foetida
 * Thapsia garganica L.
 * Thapsia gummifera
 * Thapsia gymnesica Rosselló & A.Pujadas
 * Thapsia meoides
 * Thapsia minor Hoffmans & Link
 * Thapsia nestleri
 * Thapsia nitida Lacaita
 * Thapsia pelagica
 * Thapsia platycarpa Pomel
 * Thapsia scabra
 * Thapsia smittii
 * Thapsia tenuifolia
 * Thapsia thapsioides
 * Thapsia transtagana Brot.
 * Thapsia villosa L.
 * Thapsia annua (A.Chev.) M.Hiroe (1979) (synonym : Melanoselinum annuum A.Chev. )
 * Thapsia bischoffii (Schmidt) M.Hiroe (1979) (synonym : Tornabenea bischoffii Schmidt)
 * Thapsia cinerea A.Pujadas (2003) (Morocco)
 * Thapsia decipiens Hook.f. (1867) (Madeira)
 * Thapsia decussata Lag. (1816)
 * Thapsia dissecta (Boiss.) Arán & Mateo (2002) (synonym : Thapsia villosa var. dissecta Boiss. )
 * Thapsia edulis G.Nicholson (1887) (Madeira)
 * Thapsia garganica L. (1767) (synonyms : Thapsia lineariloba Pomel, Thapsia marocana Pomel , Thapsia silphia St.-Lag. , Thapsia stenocarpa Pomel )
 * Thapsia garganica subsp. gymnesica (Rosselló & A.Pujadas) Romo (1994) (synonym : Thapsia gymnesica Rosselló & A.Pujadas )
 * Thapsia garganica subsp. messanensis (Guss.) Brullo, Guglielmo, Pasta, Pavone & Salmeri (2009) (Sicily)
 * Thapsia hirta (Schmidt) M.Hiroe (1979) (synonym : Tornabenea hirta)
 * Thapsia insularis (Parl. & Webb.) M.Hiroe -(1979) (synonym : Tetrapleura insularis)
 * Thapsia intermedia Lag. (1821) (Spain)
 * Thapsia melanoselina Masf. (1881)
 * Thapsia minor Hoffmanns. & Link (1834) (Portugal)
 * Thapsia moniza Masf (1881) (Canaries)
 * Thapsia nitida Lacaita (1928) (Spain)
 * Thapsia nitida subsp. meridionalis (A.Pujadas) Rivas Mart. (2002)
 * Thapsia pelagica Brullo, Guglielmo, Pasta, Pavone & Salmeri (2009)
 * Thapsia platycarpa Pomel (species recently differentiated from Thapsia garganica)
 * Thapsia polygama Desf. (1798) (North Africa)
 * Thapsia praealta d'Urv. (1822) (Kos – Dodecanese)
 * Thapsia tenuissima (A.Chev.) M.Hiroe (1979) (synonym : Melanoselinum tenuissimum A.Chev. )
 * Thapsia transtagana Brot. (1804) (Portugal)
 * Thapsia villosa L. (1753) (synonyms :, Thapsia microcarpa Pomel, Thapsia stenoptera Pomel) (Iberian peninsula)
 * Thapsia villosa var. laciniata (Rouy) O.Bolòs & Vigo (1974) (synonym : Thapsia laciniata Rouy )
 * Thapsia villosa subsp. maxima (Mill.) O.Bolòs & Vigo (1974) (synonym : Thapsia maxima Mill. )
 * Thapsia villosa var. platyphyllos Franco & P.Silva. (1971) -->