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Section Austrastrophytum
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Section Septentriastrophytum
and subgenus Stigmatodactylus |
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| fertility | only plants of the section can be crossed | only plants of the section can be crossed* *obviously A. caput-medusae cannot be crossed *A. coahuilense with Astrophytum capricorne v. senile limited (natural hybrid!) |
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| geography |
habitat south
|
habitat north
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| trend |
evolutionary older
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evolutionary younger
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| species | A. ornatum | A. myriostigma | A. coahuilense | A. capricorne | A. caput-medusae | A. asterias |
| field distance to A. ornatum |
- | little | medium | medium bis groß | wide | very wide |
| height | very tall | medium | medium | medium | small | small |
| spines | yes | no | no | yes | yes | no |
| mimikry | no | stones | stones | grass | shrubs | environment |
| fruit | little fleshy | little fleshy | little fleshy | little fleshy | nearly dry | nearly dry |
| fruit opening | at the top | at the top | at the bottom | at the bottom | at the side | irregular |
| number of seeds |
little
|
many | many | little | medium | |
| reduction of the cotyledons | little | a little more | very | very | at least | most |
| succulence of the hypocotyl | little | a little more | high | high | at least | highest |
| secondary warts | no | no | no | no | yes | no |
| serial division of the areole | no | no | no | no | yes | no |
| pollen-deformity | 5 % ?? | 5-20 % | 8-21 % natural hybrid! |
4-16 % | ? | 5-15 % |
| flower throat | yellow | yellow | red-orange | red-orange | red-orange | red-orange |
| maturity |
late
|
medium | early? | early | ||
The species of the genus Astrophytum point in the presentation from left to right thr more specialized, more sophisticated features and are evolutionarily younger. The distribution area correlates so from south to north. Basically, all cacti in the evolution do shortening of the vegetative phase, (body size, maturity). The specialization in mimikry, flower and the thorn loss supplement these findings. The posibility of crossing the species among themselves may not be used, as has already been executed elsewhere. If pollen-deformity is significant, can not decided today because there are only few investigations. (MEGATA, 1944).
Astrophytum caput-medusae of the subgenus Stigmatodactylus has very sophisticated features, but even relatively primitve (in the table pink background)
BUXBAUM (1950-55) wrote in his Morphology of Cacti auf S. 30 "...TROLL found that seedlings of Astrophytum asterias form ribs almost immediately...". Daraus wurde später in HAAGE / SADOVSKY, dass BUXBAUM brieflich mitteilt, Astrophytum asterias bilde ohne vorher Mamillen zu besitzen sofort Rippen. Die Autoren oder BUXBAUM haben leider das Wort "almost" vergessen??
TAYLOR, N. P., CLARK, J. Y. come for the geographical direction of evolutionary development of the genus Ferocactus also to a South> North proliferation (old> young) as they seem to match with Astrophytum.
literature:
BUXBAUM, F. (1963b): Die Kakteenblüte und das "Gesetz der Verkürzung der vegetativen Phase", Kakt. and. Sukk. 14 (1): 2-5
BUXBAUM, F. (1963c): Die Kakteenblüte und das "Gesetz der Verkürzung der vegetativen Phase" (Schluß), Kakt. and. Sukk. 14 (2): 22-25
BUXBAUM, F. (1950-55): Morphology of Cacti, Abbey Garden Press, Pasadena
HAAGE, W.; SADOVSKY, O. (1957): Kakteen-Sterne, die Astrophyten, Neumann-Verlag, Radebeul
HOOCK, H. ( 1993): Ist Astrophytum coahuilense (MOELLER) KAYSER ein Naturhybrid?, Kakt. and. Sukk. 44(2): 37-44
MEGATA, M. (1944): An Account of the Genus Astrophytum LEMAIRE in: Memoirs of the College of Agriculture, No. 56, Kyoto Imperial University
TAYLOR, N. P.; CLARK, J. Y. (1983): Seed-morphology and classification in Ferocactus subg. Ferocactus, Bradleya 1/1983 p. 3-16
genus Astrophytum
The evolution of der Astrophyten
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