Au dernières nouvelles, il n'est pas possible de faire la différence entre abruptibulbus, essettei, et sylvicola sur base de caractères macro ou microscopiques...
Pour citer L Parra In "Agaricus vol II, 2013" p196
"In fact, both A. abruptibulbus and A. essettei as well as A. sylvicola may exhibit either a cylindraceous to clavate stipe or it can be more or less bulbous,..."
pp 224-225
"Among these species (each including several collections) sequenced for this study, Agaricus sylvicola, A. essettei, A. macrocarpus and A. greuteri, are those morphologically, most similar to A. abruptibulbus, but they are phylogenetically rather distant. In point of fact, macroscopic characters cannot be used to distingish them from A. abrutibulbus, and even microanatomy is of no great help since the cheilocystidia are very similar in all of them, and the spore measures of A. abruptibulbus overlap to a large extent those of the other four taxa..."
La seule méthode valable et décrite est le séquençage d'une région nommé ITS1+2 et la comparaison des délétions et remplacements de paires de base après alignements de séquences.
Poor lonesome mushroom hunter...
