Hladnikia

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Asterids
Cladus: Campanulids
Ordo: Apiales

Familia: Apiaceae
Subfamilia: Apioideae
Tribus: Careae
Genus: Hladnikia
Species: H. pastinacifolia
Name

Hladnikia Rchb. ex Rchb. Iconogr. Bot. Pl. Crit. 9: 9. (1831)

monotypic taxon

References

Reichenbach, H.G.L. 1831. Iconographia Botanica seu Plantae Criticae 9: 9.
Hassler, M. 2018. Hladnikia. World Plants: Synonymic Checklists of the Vascular Plants of the World In: Roskovh, Y., Abucay, L., Orrell, T., Nicolson, D., Bailly, N., Kirk, P., Bourgoin, T., DeWalt, R.E., Decock, W., De Wever, A., Nieukerken, E. van, Zarucchi, J. & Penev, L., eds. 2018. Species 2000 & ITIS Catalogue of Life. Published on the internet. Accessed: 2018 Sept. 19. Reference page.
International Plant Names Index. 2018. Hladnikia. Published online. Accessed: Sept. 18 2018.
Tropicos.org 2018. Hladnikia. Missouri Botanical Garden. Published on the internet. Accessed: 2018 Sept. 19.

Hladnikia is a monotypic genus of flowering plants belonging to the family Apiaceae.[3] Its sole species, Hladnikia pastinacifolia, is a Slovenian paleoendemite,[4][5] restricted to the area of only 4 km2, located in Trnovo Forest Plateau, karst plateau of Western Slovenia.[6] German botanist Heinrich Gottlieb Ludwig Reichenbach named the genus after Carniolan botanist and founder of Ljubljana Botanical Garden Franz Hladnik.[4][7]
Description

Hladnikia pastinacifolia is a monocarpic herbaceous perennial plant, which takes a few vegetation periods to develop into a flowering plant.[6] Individuals, which have erect flowering stem, can reach from 15 to 30 centimetres of height.[8] At first plant's leathery and glossy leaves are simple shaped and arranged into rosettes. Later on, as their area increases, leaves also change shape into lobate.[6][8] Hladnikia pastinacifolia resembles well-known celery (Apium graveolens), but has thicker foliage and shorter leaf stems.[4] The species' root is long and lignified. The plant's flower has white, heart-shaped and 1 mm long petals.[8]

Not much is known about the plant's exact breeding system. This plant species is entomophilous and has multiple different pollinators. It is thought that outcrossing happens occasionally.[6] The species flowering period is between Mai and July.[4] After successful pollination seeds that don't have any special dispersal adaptation develop between the end of August and into September. A fruit is a schizocarp, which after maturing splits into two 4 mm sized mericarps,[6] 2 mm wide.[8]

Hladnikia pastinacifolia chromosome number is 2n = 22.[8]
Distribution and conservation

The plant is a Slovenian paleoendemic species restricted to small area (4 km2) in Trnovski gozd. There these plants grow only on southern slopes of the plateau and two isolated areas located 9 km away on the northern slopes.[6] As the plant species is not a habitat specialist its growing areas are various; Hladnikia pastinacifolia was found on stony grasslands, rock crevices and screes. Laboratory molecular analyses have shown that Hladnikia pastinacifolia is a Pleistocene survivor in situ.[8]

Even though its population trend is labeled as stable by IUCN Red list, it has data deficient (DD) conservation status.[9][1] Among mentioned threats are human intrusions and disturbance (such as recreational activities) as well as natural system modifications.[1] The Trnovo Forest Plateau is listed as Natura 2000 site.[9][10] Because of its small area of distribution and different threats the species is studied for possible cryopreservation.[5][11][12]
References

Bilz, M. (2011). "Hladnikia pastinacifolia". IUCN Red List of Threatened Species. 2011: e.T162082A5530927.
"Hladnikia pastinacifolia Rchb". www.gbif.org. Retrieved 2021-08-15.
"Hladnikia Rchb. | Plants of the World Online | Kew Science". Plants of the World Online. Retrieved 14 May 2021.
"Hladnikia pastinacifolia (rebrinčevolistna hladnikija)". www.botanicni-vrt.si (in Slovenian). Retrieved 2021-08-15.
Ciringer, Terezija (2016). Krioprezervacija rebrinčevolistne hladnikovke (Hladnikia pastinacifolia Rchb.) z optimizacijo inkapsulacijske dehidracije in vitrifikacije [Cryopreservation of Hladnikia pastinacifolia Rchb. with optimization of encapsulation dehydration and vitrification] (Thesis) (in Slovenian). OCLC 958133505. S2CID 125730341.
Šajna, Nina; Kavar, Tatjana; Šuštar-Vozliè, Jelka; Kaligariè, Mitja (1 January 2012). "Population Genetics of the Narrow Endemic Hladnikia Pastinacifolia RCHB. (Apiaceae) Indicates Survival in Situ During the Pleistocene". Acta Biologica Cracoviensia Series Botanica. 54 (1). doi:10.2478/v10182-012-0009-8.
"Info in English | Botanično društvo Slovenije" (in Slovenian). Retrieved 2021-08-15.
Sajna, Nina; Šuštar-Vozlič, Jelka; Kaligarič, Mitja (28 October 2014). "New Insights into the Anatomy of an Endemic Hladnikia Pastinacifolia Rchb". Acta Botanica Croatica. 73 (2): 375–384. doi:10.2478/botcro-2014-0005. S2CID 36596271.
"Hladnikia pastinacifolia - Rchb". eunis.eea.europa.eu. Retrieved 2021-08-15.
"ArcGIS Web Application". natura2000.eea.europa.eu. Retrieved 2021-08-15.
Mujakić, Jakup (2016). Vpliv velikosti vcepka in gojišča na regeneracijo brstov rebrinčevolistne hladnikovke (Hladnikia pastinacifolia Rchb.) v tkivni kulturi [Influence of graft size and culture medium on regeneration of Hladnikia pastinacifolia Rchb. in tissue culture] (Thesis) (in Slovenian). OCLC 958134229.
Ciringer, Terezija (2010). Mikropropagacija in krioprezervacija z inkapsulacijsko dehidracijo rebrinčevolistne hladnikovke (Hladnikia pastinacifolia Rchb.) : magistrsko delo [Micropropagation and cryopreservation with encapsulation dehydration of Hladnikia pastinacifolia Rchb] (Thesis) (in Slovenian). OCLC 781469120.