Canonical Correspondence Analysis. Hypogean fauna related to environmental factors and mineral substratum A classes of ground fauna B orders of ground fauna (Arachnida, Entognatha and Insecta) with a number of specimens exceeding 5% of each considered class total C classes of parietal fauna D orders of parietal fauna (Arachnida and Insecta) with a number of specimens exceeding 5% of each considered class total.