Svartburkni
Asplenium trichomanes ) er sjaldgæf burknategund (á Íslandi).

Undirtegundir
Asplenium trichomanes er með tvílitna (diploid), tetraploid og sexlitna (hexaploid) cytotype, sem hafa verið tilnefndar til að vera sjálfstæðar tegundir. Þrílitna (triploid) cytotype (ófrjór blendingur á milli tvílitna og fimmlitna arfgerða) þekkjast einnig. Innan þessara arfgerða (cytotypes) eru nokkrar undirtegundir viðurkenndar, þar á meðal

Asplenium trichomanes subsp. trichomanes  Diploid.
Asplenium trichomanes subsp. quadrivalens  Tetraploid.
Asplenium trichomanes subsp. pachyrachis (syn. Asplenium csikii)  Tetraploid.
Asplenium trichomanes subsp. coriaceifolium (syn. Asplenium azomanes): Majorca, Spain, Morocco. Tetraploid.
Asplenium trichomanes subsp. hastatum. Tetraploid.
Asplenium trichomanes subsp. inexpectans. Diploid.
Asplenium trichomanes subsp. maderense. Madeira, Azores. Hexaploid. Hexaploids koma einnig fyrir í Ástralíu og Nýja Sjálandi.
Asplenium trichomanes nothosubsp. staufferi. Tetraploid (pachyrachis × quadrivalens).
Asplenium trichomanes nothosubsp. barraraense. Tetraploid (coraceifolium × quadrivalens).
Asplenium trichomanes nothosubsp. lovisianum. Tetraploid (hastatum × quadrivalens).
Asplenium trichomanes nothosubsp. moravicum. Tetraploid (hastatum × pachyrachis).
Asplenium trichomanes nothosubsp. melzeranum. Triploid (hastatum × inexpectans).
Asplenium trichomanes nothosubsp. melzeri. Triploid (quadrivalens × inexpectans).
Asplenium trichomanes nothosubsp. tadei-reichsteinii. Triploid (pachyrachis × inexpectans).
Asplenium trichomanes nothosubsp. lusaticum. Triploid (trichomanes × quadrivalens).
Asplenium trichomanes nothosubsp. malacitense. Triploid (coraceifolium × inexpectans).

Tilvísanir

Flora of North America. Asplenium trichomanes. Accessed 13 August 2008.
Hutchinson, G. (1996) Welsh Ferns, National Museums and Galleries of Wales.
Page C. N. (1982) The Ferns of Britain and Ireland, Cambridge University Press.
Preston, C. D. & Pearman, D. A. (2002) New Atlas of the British and Irish Flora, Oxford University Press.
Stace, Clive A. (1997) New Flora of the British Isles, Cambridge University Press.
Tutin, T. G. et al. (1964) Flora Europaea, Volume 1. Cambridge University Press.

Ytri tenglar
BSBI Maps: Distribution in Britain and Ireland
Plants for a Future database

Burknar
Burknar