Diphasiastrum

Summary

Diphasiastrum is a genus of clubmosses in the plant family Lycopodiaceae. In the Pteridophyte Phylogeny Group classification of 2016 (PPG I), it is placed in the subfamily Lycopodioideae.[1] It is closely related to the genus Lycopodium, and some botanists treat it within a broad view of that genus as a section, Lycopodium sect. Complanata. Some species superficially resemble diminutive gymnosperms and have been given common names such as ground-pine or ground-cedar.

Diphasiastrum
Diphasiastrum complanatum (previously called Lycopodium complanatum).
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Lycophytes
Class: Lycopodiopsida
Order: Lycopodiales
Family: Lycopodiaceae
Subfamily: Lycopodioideae
Genus: Diphasiastrum
Holub
Species

See text

Diphasiastrum complanatum

There are 16 species, and numerous natural hybrids in the genus; many of the hybrids are fertile, allowing their occurrence to become frequent, sometimes more so than the parent species. The basal chromosome count for this genus is n=23, which is distinctively different from other lycopods.[citation needed]

Several species have been used economically for their spores, which are harvested as Lycopodium powder.

Species edit

As of January 2023, the Checklist of Ferns and Lycophytes of the World recognized the following species:[2]

Selected hybrids edit

Some species are treated as hybrids, although not by all sources:[2]

  • Diphasiastrum × habereri (House) Holub (D. digitatum × D. tristachyum)
  • Diphasiastrum × issleri (Rouy) Holub (syn. D. issleri, D. alpinum × D. complanatum)
  • Diphasiastrum × oellgaardii Stoor, Boudrie, Jérôme, K.Horn & Bennert (D. alpinum × D. tristachyum)
  • Diphasiastrum × sabinifolium (Willd.) Holub (syn. D. sabinifolium, D. sitchense × D. tristachyum)
  • Diphasiastrum × takedae Ivanenko (D. alpinum × D. sitchense)
  • Diphasiastrum × verecundum A.V.Gilman (D. complanatum × D. digitatum)
  • Diphasiastrum × zeilleri (Rouy) Holub (D. complanatum × D. tristachyum)

Distribution edit

The genus has a subcosmopolitan distribution, in much of the Northern Hemisphere, south in mountains to South America (reaching furthest south in Jujuy Province, northwest Argentina), New Guinea and the Marquesas Islands in the Pacific Ocean, but confined to climates with high humidity for most or all of the year (or, in cool climates, protected by snow cover in winter).

References edit

  1. ^ PPG I (2016), "A community-derived classification for extant lycophytes and ferns", Journal of Systematics and Evolution, 54 (6): 563–603, doi:10.1111/jse.12229, S2CID 39980610
  2. ^ a b Hassler, Michael (19 January 2023), "Diphasiastrum", World Ferns. Synonymic Checklist and Distribution of Ferns and Lycophytes of the World, 14.7

External links edit

  • Holub, J. 1975. Diphasiastrum, a new genus in Lycopodiaceae. Preslia 14: 97-100.
  • Flora of North America - Diphasiastrum
  • Photo of D. complanatum
  • Picture and information Archived 2005-02-07 at the Wayback Machine
  • Pictures