Mesoplophora michaeliana Berlese , 1904
Mesoplophora Michaeliana Berlese, 1904b, p. 23, pl. 2 fig. 51.
Phtiracarus (Phtiracarulus) perexiguus Berlese, 1920a, p. 149.
Meshoplophora michaeliana, Lombardini, 1936, p. 44.
Until recently, M. michaeliana (the type-species of the genus) had never been found again. Although the original description is sufficient for identification, new material of the type-species was indispensable in order to give a detailed definition of the genus.
In the Berlese Collection several specimens of the species are present. By means of the catalogue I found the following preparations: 26/36, 209/16, 214/2 (all from the garden of the "Stazione di Entomologia Agraria" at Florence); 70/6, 7, 8, 9 (from the Boboli Gardens, Florence); 214/1 (Cascine, Florence); 209/14, 15 (Florence). None of them is designated as type, for which reason I select no. 26/36 as such; consequently the garden of the "Stazione di Entomologia Agraria" (Florence) must be considered the type-locality. In this small garden I collected indeed a number of topotypic specimens, the detailed redescription of which will be published in a monograph on the Mesoplophoridae .
Apart from adults of M. michaeliana, slide no. 70/7 contains some small ptychoid specimens that Berlese identified with Phtiracarus minimus (now Pseudotritia minima); the preparation did not permit of a definite conclusion.
I found also two slides (nos. 209/19, 20, from the garden of the "Stazione di Entomologia Agraria", Florence) with the types of Phtiracarus (Phtiracarulus) perexiguus . Because these specimens appear to be juveniles of Mesoplophora michaeliana, the subgenus Phtiracarulus (of which perexiguus is the type) becomes a synonym of Mesoplophora, whilst the species must be placed in the synonymy of M. michaeliana . In slide no. 209/20 I distinctly recognized a deutonymph. The specimen described by Berlese as a hexapod nymph is of course a larva. I remark that the juveniles of Mesoplophora are scleritized; they remind of adult ptychoids.