A new species of Diplocladiella (Ascomycota) from the lower Holocene of Argentina: new insight into the palaeoecological and palaeoclimatic history of the fossil genus Triporicellaesporites

Abstract

Mycopalynology offers the possibility of describing new fossil fungal species, and re-evaluating existing fossil taxa based on their nearest living relatives. Ecological analysis of fossil fungal communities also informs palaeoclimate reconstructions. The current study describes a new species of Diplocladiella from the early Holocene of South America, proposes the synonymy of the fossil genera Triporicellaesporites and Diplocladiella, and provides three new name combinations.The occurrence of Diplocladiella arambarriae sp. nov. in the Argentine Mesopotamia region contributes to our knowledge of the palaeomycological diversity of this area. The description of this new freshwater fungus and synonymization of the fossil genera Triporicellaesporites and Diplocladiella allows us to reinterpret the palaeoecological value of fossil stauroconidia. The palaeoenvironment of the Mesopotamian region of Argentina in the early Holocene is reconstructed as being warmer and more humid than at present. Synonymization of the genera extends the range of Diplocladiella to 66 Ma and offers the possibility of using these fungi as complementary palaeoenvironmental proxies.