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High-resolution imaging reveals a large morphological variety ofprotoplanetary disks. To date, no constraints on their global evolution havebeen found from this census. An evolutionary classification of disks wasproposed based on their IR spectral energy distribution, with the Group Isources showing a prominent cold component ascribed to an earlier stage ofevolution than Group II. Disk evolution can be constrained from the comparisonof disks with different properties. A first attempt of disk taxonomy is nowpossible thanks to the increasing number of high-resolution images of HerbigAe/Be stars becoming available. Near-IR images of six Group II disks inscattered light were obtained with VLT/NACO in Polarimetric DifferentialImaging, which is the most efficient technique to image the light scattered bythe disk material close to the stars. We compare the stellar/disk properties ofthis sample with those of well-studied Group I sources available from theliterature. Three Group II disks are detected. The brightness distribution inthe disk of HD163296 indicates the presence of a persistent ring-like structurewith a possible connection with the CO snowline. A rather compact (less than100 AU) disk is detected around HD142666 and AK Sco. A taxonomic analysis of 17Herbig Ae/Be sources reveals that the difference between Group I and Group IIis due to the presence or absence of a large disk cavity (larger than 5 AU).There is no evidence supporting the evolution from Group I to Group II. GroupII are not evolved version of the Group I. Within the Group II disks, verydifferent geometries (both self-shadowed and compact) exist. HD163296 could bethe primordial version of a typical Group I. Other Group II, like AK Sco andHD142666, could be smaller counterpart of Group I unable to open cavities aslarge as those of Group I.

Evolution of protoplanetary disks from their taxonomy in scattered light: Group I vs. Group II