Espèce
Ajouter à vos listes :
J'en propose
   
J'en cherche
   
Une de mes préférées
    aide sur les listes

Espèce proposée par :
Aucun membre ¯\_(ツ)_/¯

Fiche no 65505.
Auteurs : Modifier - Effacer - Changer en espèce

encyclo_admin@cactuspro.com

Sponsor du CF
Agenda
20 et 21 avril 2024
Foire aux plantes du château de la Ferté (Saint-Ambreuil, 71, France)
J'y vais
20 et 21 avril 2024
Printemps aux Jardins (Aiffres, 79, France)
J'y vais
20 et 21 avril 2024
Printemps du Bourgailh (Pessac, 33, France)
J'y vais
20 et 21 avril 2024
Courtanvaux côté jardin (Bessé sur Braye, 72, France)
J'y vais
20 et 21 avril 2024
JardiPlantes (Garlan, 29, France)
J'y vais
20 et 21 avril 2024
Marché aux Fleurs - La Baule (La Baule-Escoublac, 44, France)
J'y vais
Toutes les dates

Opuntia margaritana (J.M.Coulter) E.M. Baxter 1931

Publication Notes on Opuntia pycnantha, Journal of the Cactus and Succulent Society of America (Los Angeles) 2(7) : 388 (386-) (1931).
Basionyme Opuntia pycnantha v. margaritana J.M.Coulter 1896

Synonyme de

Opuntia pycnantha Engelmann ex J.M.Coulter 1896

Commentaires

Publication originale (E.M.Baxter 1931) :
« DISTRIBUTION: Opuntia pycnantha is found only in the region of Magdalena Bay, the mainland plants probably having come from the islands—Santa Margarita and Magdalena. At Puerto Chale is found the plant in its typical form. Further north, near Medanos Amarillos, Howard Gates of Anaheim collected some plants growing deep in the sand hills close to the coast. Although not definitely reported, it can be expected to be found between these two points. The two small islands do not have it as they are little more than tidal flats and are covered with mangrove trees.
In their "Cactaceae," Volume I, Drs. Britton and Rose say that Opuntia pycnantha is found ONLY on Magdalena Island and that the variety margaritana is found ONLY on Margarita Island. Probably an incomplete collection was made because at the present time the distribution of both is quite wide over both islands.
Dr. Rose collected specimens at Santa Maria Bay in 1911. The shaded area on the map shows the extreme reported limits of the species.
DESCRIPTION: On Margarita Island it grows in its typical form, i.e., yellow spines and glochids, spines l/4 to l/2 inch long, aciculate, several to an areole; glochids large, numerous; areoles large and closely set; joints oblong to orbicular, 8 to 10 inches (20-25 cm.) long, thick, nearly hidden by the spines; flowers yellow.
It is described by Brandegee as "a plant resembling Opuntia chlorotica and probably the same."
The same form is found on Magdalena Island with another form in addition. It is found growing alongside of the type. It has fewer areoles, but the remarkable difference is in the length and size of its spines. These are one or two to an areole, two inches long, flattened, and reflexed close against the stem. It bears also the typical spines.
There are no intermediate stages between the two and as the one may grow intermingled with the other it would seem to not be a geographical or climatical variety. This second form is not found on Margarita Island. As to whether or not this form should receive varietal distinction I do not wish to say. That it is different, I am sure; but that these differences may not also appear in plants of the true type I am not so certain, and must wait for the results of experiments to know.
Opuntia pycnantha was first described by Engelmann in 1889. The variety margaritana was described, as a variety, by Coulter in 1896. The distinction is in the color of spines. Opuntia pycnantha has spines and glochids of a canary yellow color. Those of the variety Opuntia pycnantha margaritana are dark red or red-brown in color. There are no plants with graduated or intermediate colors between the two.
Only a few flowers were seen. Those of the variety were more cream colored than the bright yellow of Opuntia pycnantha. The old flowers of Opuntia pycnatha margaritana are a deep maroon color, strong enough to stain the fingers when bruised. I did not see any old flowers of the type species.
Both the species and the variety have the long-spined form mentioned before. With the two spine forms in both varieties, there are four distinct forms of Opuntia pycnantha on Magdalena Island.
The growth is generally bush-like, branching from a common stem only one or two joints above the ground. It is three feet high and spreads to a diameter of five feet, although very irregular. Quite often it is found creeping on the ground with two to five branches from the stem pad growing radially with a single, chainlike series of pads in each branch. This characteristic is sometimes found combined with a bushy plant above it. These growths were found only on elevated portions of the gravelly beach along the bay coast and is probably caused by the insufficient supply of water that they receive in that position. A photograph of Opuntia pycnantha is reproduced on page 324, Volume II, Number 4, of the Journal.
Whenever a character is permanent in any member of a genus, that is, is present under every circumstance of climate, geography, reproduction, etc., it must be considered a specific character of that plant. When, in addition, it maintains the distinction while having every opportunity (apparently) through close contact to cross with another variety of quite similar characteristics, then we are bound to grant it specific distinction.
The stability of the characteristic difference of the variety margaritana leads me to suggest that they are of specific quality and that the variety should be made a species; that it should precede Opuntia pycnantha in the Basilares series, and take the varietal name for its specific designation.
To many, who feel overburdened with lengthy and minutely differentiated names and divisions, this suggestion will not be welcome. I believe, though, as someone before has said, that "organization is division," decrying at the same time the granting of specific rank to imperfectly known or carelessly studied varieties.
Opuntia margaritana would then be described as follows:
Opuntia margaritana (Coulter) sp. nov.
Bushy, 2 to 4 feet high, branching from near the ground. Spines and glochids red-brown; spines l/4 to l/2 inch long, aciculate, several to an areole; glochids large, numerous. Areoles large and closely set. Joints flattened, oblong to orbicular, 8 to 10 inches (20-25 cm.) long, thick, papillose. Flowers, cream-yellow when fresh, deep maroon when old. Stems grayish-green in color, appearing red-brown from a distance because of the dense covering of spines. »

Étymologie

- Opuntia : Du nom d'une plante citée par Théophraste (vers 371-288 av. J.C.) dans son Histoire des plantes, repris par Pline l'ancien (23-79) dans son Histoire Naturelle, plante qui poussait près de la ville d'Oponte dans la Grèce antique, et qui se reproduisait par bouture de feuille.
- margaritana : en référence à la localité d’origine, l’île de Santa Margarita, en Basse Californie du Sud au Mexique.

Numéros de collecte

Vous pouvez chercher les numéros de collecte pour cette espèce dans :

Forum

Vous pouvez faire une recherche sur le forum.

Auteur

philippe (contacter l'auteur ou écrire aux admins de l'encyclopédie)
Fiche créée le 16/05/2018.


Fiches de botanistes :

image disponible Coulter, John Merle

Fiche du genre :

image disponible Opuntia (Linné) Miller 1754

Synonymes :

Aucune fiche.

Espèces du même genre :

image disponible Opuntia aciculata Griffiths
image disponible Opuntia aequatorialis Britton & Rose
image disponible Opuntia ammophila Small 1919
image disponible Opuntia austrina Small 1933
image disponible Opuntia bakeri Madsen
image disponible Opuntia basilaris v. basilaris Engelmann & Bigelow 1857
image non disponible Opuntia basilaris v. brachyclada (Griffiths) Munz 1935
image non disponible Opuntia basilaris v. humistrata (Griffiths) W.T.Marshall 1941
image disponible Opuntia chaffeyi Britton & Rose
image disponible Opuntia ficus-indica (L.) Miller 1768
image disponible Opuntia humifusa (Rafinesque) Rafinesque
image disponible Opuntia leucotricha de Candolle
image disponible Opuntia microdasys (Lehmann) Pfeiffer
image disponible Opuntia monacantha (Willdenow) Haworth
image disponible Opuntia pubescens H.L.Wendland
image disponible Opuntia pycnantha Engelmann ex J.M.Coulter 1896
image disponible Opuntia quimilo K.Schumann
image disponible Opuntia quitensis F.A.C.Weber
image disponible Opuntia rastrera F.A.C.Weber
image disponible Opuntia robusta H.L.Wendland
image disponible Opuntia rufida
image disponible Opuntia salmiana J.Parmentier ex Pfeiffer 1837
image non disponible Opuntia tenuiflora Small 1933
image non disponible Opuntia tuna (Linné) Miller
image disponible Opuntia turbinata Small 1933
image disponible Opuntia undulata Griffiths