family Family I, philum cyanobacteria.] Both sequences found very little similarity with our probe pairs, with internal mismatches and a different base in the discriminating position. Anyway, the probe pair itself was successfully tested on the synthetic template. The failure of ORMAdesigned Anabaena + Aphanizomenon probe pair suggests the possibility of making a re-design in the near future, increasing the number of sequences of the database and improving the information content of the dataset. Another strategy could be designing probe pairs on subclusters of Anabaena + Aphanizomenon, building new consensuses from more homogeneous groups; in this way, the presence of such two species would be assessed by multiple probe pairs and not only by one.