Fig. 11From: Life as a fortress – structure, function, and adaptive values of morphological and chemical defense in the oribatid mite Euphthiracarus reticulatus (Actinotrichida)A schematic evolutionary scenario for the development of oil gland compounds and defensive secretion amounts in the Ptyctima (Euphthiracaroidea and Phthiracaroidea) and the proposed outgroup - the Collohmannioidea - summarizing currently available data. The dashed line connecting Euphthiracaridae and Oribotritiidae denotes unsolved phylogenetic relationships among both taxa. Furthermore, the Synichotritiidae, a euphthiracaroid family that has lost the glands (see text), is omitted. I = δ-acaridial; II = β-springene; a = chrysomelidial; b = 2-hydroxy-6-methylbenzaldehyde; c = citral (geranial/neral); d = γ-acaridial; e = neryl formateBack to article page