[Evaluation of Psilocybe cubensis (Agaricales, Basidiomycota) toxicity over Artemia franciscana (Crustacea, Anostraca)].

Background: Psilocybe cubensis is a species with psychodysleptic action that grows on cattle dung in pastures in the tropics and subtropics. This fungus has been widely used in Mexico since ancient times both for ceremonies and rituals, as well as for healing or medicinal purposes. Artemia franciscana is a crustacean frequently used as a model organism for toxicity testing.

Aims: With the objective of determining the toxicity of P. cubensis, the results of a study with the extract of P. cubensis on nauplii and adults of the brine shrimp A. franciscana are presented.

Methods: Specimens were collected at Bahía de Banderas, Jalisco, Mexico, and were dried and homogenized in artificial sea water. Bioassays were carried out on crystal vials filled with different concentrations of the extract of P. cubensis (EAP), and with potassium dichromate as reference toxic compound. The median lethal concentration (LC(50)) in nauplii and adults and the inhibition of cysts hatching in A. franciscana were calculated.

Results: Nauplii showed a LC(50) = 135 μg/ml, while adults a LC(50) = 172 μg/ml. Cysts' hatching was inhibited by the EAP at all tested concentrations.

Conclusions: Under the conditions of this study, the extract of P. cubensis was toxic for nauplii and adults of A. franciscana.