Recent molecular studies have clarified the phylogenetic relations within the family Reticulariaceae (Myxomycetes, Myxogastrea), allowing to reconstruct the ways of the morphological evolution within the family. We conclude, that the general tendency of the sporophore evolution in Reticulariaceae was the transformation of the stalked forms to the sessile ones, followed by the development of the metameric sporophores, called pseudoaethalia and aethalia, from the separate sporocarps. The common ancestor of the family was similar to Alwisia lloydiae having stalked sporocarps and tubular capillitium. At least four evolutionary lineages originated form this ancestor: 1) Alwisia → Tubifera, 2) Alwisia → Rigidotubula (and probably Siphoptychium), 3) Alwisia → (Lycogala) → Thecotubifera, 4) Alwisia → Lycogala → Reticularia. In each of these branches, the processes like a loss of stalks, transition from spherical to elongated sporothecae, transformation of solitary sporocarps to grouped ones, a loss of capillitium and formation of pseudocapillitium, have occurred independently. Therefore, the type of the fruiting body, and presence of capillitium or pseudocapillitium, cannot be considered as sufficient criteria for separating myxomycete genera.
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