Antirrhinum majus m. m. var. striatum/pseudomajus
- Phenotype shifts across the transition zone mirror genotypic gradients.
- Hybrid marker values shift gradually from near zero to nearly 1.
- Both subspecies share an identical chloroplast genome.
- The hybrid peak is moving uphill.
- Evidence points to an internal mechanism, not hybridization between the two subspecies.
Distribution of Antirrhinum majus m. var. striatum
The white-green circles mark the Avellanet and Planoles populations in transition. There may be additional transitional populations in France and Spain along the southern border of the subspecific striatum's distribution range.
For a quick overlook of this "hybrid" or transition zone West of Planoles, press here:
https://www.antspec.org/hz (2013) Phenotype counts in 2013
a state observed in 2013. However, the situation has changed significantly by 2025.
1) There are more and more truly magenta-flowered pseudomajus individuals with perfect white-yellowish mouthparts as of 2013.
2) The ROS1/sulf - Front has been shifted to the West on both roads for at least 100 meters.
3) Along "Carr. de Dorria," individuals with yellow flowers are still in the majority, but there appears to be an increasing number of individuals with colors in between or even magenta.
That's what one can see during the last eight years along the roads. There is also a bloom in the second half of September, when parts of the plants start to bloom.
Plot of readings according to the "Snapdragon-Group". Additionally the
Centers of the hybrid zones along EiX and GIV are marked (our contribution). There has been a slow shift to the West for these centers on both roads in the last seven years (HZ18 -> HZ25).
Genetic markers perform the hybrid index.
Symbolic picture, see Fig. 2 in 2025K:
Mean hybrid index (x) of all demes is [0 < x < 1]. In each deme, a smaller or bigger part of the opposite alleles is always present. It follows that this "hybrid" system cannot be described with absolute certainty by regular evolutionary theories. - Unusually high mention of the term «Selection» does not simply clarify the foundations; rather, it is a vague term.
However, one can assume that the phenotypic cline follows the genetic cline for ROS1, EL, and SULF.
Chloroplast Genome
The chloroplast genomes of the two varieties of the subspecies pseudomajus and striatum are 100% identical with respect to the coding regions of over 120 genes along the circular DNA strand. A few intergenic spacer regions differ in the length of their short tandem repeats, indicating slightly different regulation of the neighboring genes. Another fact is that, as long as one has 100% identical chloroplast genomes, it is hard to imagine a second contact between these two subspecies because cp-genome changes are the last to occur. In other words, if there is no substantial difference between the two chloroplast genomes, there cannot be a considerable time in separation. Separation over a long time means always differentiation.
Two versions of the CP data display:
A) Data from the subspecies pseudomajus and striatum
 | A_psd:str_CP.docx (429.37KB) |
| A_psd:str_CP.docx (429.37KB) |
B) Data from A. majus majus
One could find all four STRs in all CP genomes.
see; MISOPATES
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04-05-'26 rolfy