Family. Equisetaceae
Fam: Equisetaceae
Genus: Equisetum L.
English Name: Equisetaceae, Horsetail familyDescription:
Equisetaceae, sometimes called the horsetail family, is the only extant family of the order Equisetales, with one surviving genus, Equisetum, which comprises about twenty species.[1]
Evolution and systematics
Equisetaceae is the only surviving family of the Equisetales, a group with many fossils of large tree-like plants that possessed ribbed stems similar to modern horsetails. Pseudobornia is the oldest known relative of Equisetum; it grew in the late Devonian, about 375 million years ago and is assigned to its own order.
All living horsetails are placed in the genus Equisetum. But there are some fossil species that are not assignable to the modern genus. Equisetites is a "wastebin taxon" uniting all sorts of large horsetails from the Mesozoic; it is almost certainly paraphyletic and would probably warrant being subsumed in Equisetum. But while some of the species placed there are likely to be ancestral to the modern horsetails, there have been reports of secondary growth in other Equisetites, and these probably represent a distinct and now-extinct horsetail lineage. Equicalastrobus is the name given to fossil horsetail strobili, which probably mostly or completely belong to the (sterile) plants placed in Equisetites.[2]
From Wikipedia, the free encyclopedia
Genera
1. The vagina with 3 to 5 large teeth. Spore-bearing stems are chlorophyll-free and simple, later turn green and branch. The branches
branched drooping, gathered in many vertebrae .............................................................................................. ( 5) E. sylvaticum L.
1*. Vaginas with six or more tiny teeth; plants with other characteristics .......................................................................................... 2.
2. The stems are chlorophyll-free and simple. Infertile chlorophyll-bearing and branched ............................................................... 3.
2*. Spore-bearing stems green, resembling barren ......................................................................................................................... 4.
3 Vaginas with 6 to 12 lanceolate teeth ............................................................................................................ (1) E. arvense L.
3*. Vaginas with 20 to 30 awl teeth .............................................................................................................. (2) E. telmateia Ehrh.
4 Spore-bearing class at the tip obtuse; stem smooth or almost .smooth ....................................................................................... 5.
4*. The spor bearing class with a sharp tip; the stem is usually rough ............................................................................................... 6.
5 Vagina funnel-shaped, non-adjacent, with up to 10 teeth, with white membranous edge .................................... (4) E. palustre L.
5*. Vagina almost cylindrical with 15 - 30 teeth, almost without white edge, black .....................……………….... (3) E. limosum L.
6 Vaginas, extended upwards, back conical, ending in teeth, extended in a filamentous, white, membranous, deciduous tip; stem
strongly branched. ............................. ................................................................................................ ... (6) E. ramosissimum Desf.6*. Upper vagina adjacent to the stem, cylindrical, with very short, blunt and black teeth; stem unbranched ......…… (7) E. hiemale L.
From: „Флора на България”, Н. Стоянов, Б. Стефанов, Б. Китанов, том I, Изд. „Наука и Изкуство”, София, (1966)
Distribution in Bulgaria: (Conspectus of the Bulgarian Vascular Flora) = conspectus&gs_l= Zlc.
Distribution:
References: Wikipedia, the free encyclopedia, „Флора на България”, Н. Стоянов, Б. Стефанов, Б. Китанов, том I, Изд. „Наука и Изкуство”, София, (1966)
GENERA:
Genus Equisetum L. - Horsetail
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