Genus Astrophytum
key to the species
key to the species
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Section Austrastrophytum 1)
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fruits splitting starlike on the top
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| 1...plants with spines | A. ornatum |
| 2...plants spines wanting | A. myriostigma |
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Section Septentriastrophytum 2)
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fruits bursting at the base, longitudinal or not bursting
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| 1...fruits bursting at the base: | |
| 1.1.plants with spines | A. capricorne |
| 1.2.plants wanting spines | A. coahuilense |
| 2...fruits not bursting: | A. asterias |
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Subgenus Stigmatodactylus D. Hunt
fruits bursting irregular, longitudinal |
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| only one species | A. caput-medusae |
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key to the varieties
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| Astrophytum ornatum | |
| Astrophytum myriostigma | |
| Astrophytum capricorne | |
| Astrophytum caput-medusae - no varieties are known until today | |
| Astrophytum coahuilense - no valid varieties | |
| Astrophytum asterias - no valid varieties | |
| Gattung / genus Astrophytum |
| Astrophytum asterias |
| Astrophytum capricorne |
| Astrophytum caput-medusae |
| Astrophytum coahuilense |
| Astrophytum myriostigma |
| Astrophytum ornatum |
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collection Heinz Hoock
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Following the rules of ICBN this section should be named "Astrophytum" because it contains the type A. myriostigma. But in this work the old Megata name is prefered (see below).
2) Septentriastrophytum is named by the Latin word "septentrio" (= septemtrio) which means northern.
For the division of the sections the nomenclature used by Megata (1944) is taken because it points out the natural area distribution. The species key is not only orientated at the characteristic of the opening of the fruit, Backeberg (1960) but also reflects the crossing barrier between the sections and the evolution development steps.
Astrophytum coahuilense obviously derives from a natural crossing between the precursors of Astrophytum myriostigma and Astrophytum capricorne. It owns the generative characteristics from the section Septentriastrophytum and the vegetative ones from the section Austrastrophytum.
Key to the species by other authors:
spines Schumann (1903)
spines Britton et Rose (1922, 1937)
fruit opening and flower throat-colour Backeberg (1937)
flower, fruit, seed Megata (1944)
spines others (1941-1960)