TY - JOUR JF - Acarologia T1 - Is 7-hydroxyphthalide a natural compound of oil gland secretions? – Evidence from Archegozetes longisetosus (Acari, Oribatida) VL - 51 IS - 2 SP - 229 EP - 236 PY - 2011 SN - 0044-586X SN - 2107-7207 PB - Les Amis d'Acarologia AU - Heethoff, M. AU - Raspotnig, G. UR - https://doi.org/10.1051/acarologia/20112004 DO - 10.1051/acarologia/20112004 DA - 2011-06-30 ET - 2011-06-30 KW - gamma-acaridial KW - 7-hydroxyphthalide KW - chemical ecology KW - artifact AB - The monophyly of a clade consisting of Astigmata and some of the glandulate Oribatida is supported by a synapomorphic set of five oil gland-derived secretion compounds (neral, geranial, neryl formate, 2-hydroxy-6-methylbenzaldehyde (=2,6-HMBD) and 2-formyl-3-hydroxybenzaldehyde (=gamma-acaridial)), known as ‘Astigmata compounds’. Another aromatic compound, 7-hydroxyphthalide, was reported for Astigmata and Oribatida, but is not known from any other source in nature. It was discussed whether this compound was a ‘natural’ part of oil gland secretions (and thus probably of phylogenetic significance) or an artifact. Here, we show that 7-hydroxyphthalide is the result of a post-extraction chemical transformation of gamma-acaridial, and not a natural compound of oil gland secretions. We compared time series of raw extracts from Archegozetes longisetosus stored at -20°C with extracts stored at +23°C and show that storage at room temperature conditions promotes the transformation. However, since this reaction is quantitatively coherent, summing the amounts of both components seems to be a suitable approximation for the quantity of gamma-acaridial in natural secretions, even if 7-hydroxyphthalide is found in the analyses. ER -