Neoprotoparmelia gen. nov. and Maronina (Lecanorales, Protoparmelioideae): species description and generic delimitation using DNA barcodes and phenotypical characters.

Garima Singh,Jürgen Otte,Ana Crespo,Pradeep K Divakar,Víctor J Rico,H Thorsten Lumbsch,Imke Schmitt,Marcela Eugenia Da Silva Cáceres,André Aptroot

doi:10.3897/mycokeys.44.29904

Abstract

Multilocus phylogenetic studies revealed a high level of cryptic diversity within the lichen-forming fungal genus Maronina (Protoparmelioideae, Parmeliaceae). Coalescent-based species delimitation suggested that most of the cryptic molecular lineages warranted recognition as separate species. Here we study the morphology and chemistry of these taxa and formally describe eight new species based on phenotypical and molecular characters. Further, we evaluate the use of ITS rDNA as a DNA barcode for identifying species in this genus. For the first time, we obtained an ITS sequence of Maroninaaustraliensis, the type species of the genus and showed that it is phylogenetically not closely related to species currently placed in Maronina or Protoparmelia. We assembled a dataset of 66 ITS sequences to assess the interspecies genetic distances amongst the twelve Maronina species using ITS as DNA barcode. We found that Maronina and Protoparmelia form a supported monophyletic group whereas M.australiensis is sister to both. We therefore propose a new genus Neoprotoparmelia to accommodate the tropical-subtropical species within Protoparmelioideae, with Neoprotoparmeliacorallifera as the type, N.amerisidiata, N.australisidiata, N.brasilisidiata, N.capensis, N.crassa, N.pauli, N.plurisporibadia and N.siamisidiata as new species and N.capitata, N.isidiata, N.multifera, N.orientalis and N.pulchra as new proposed combinations. We provide a key to Neoprotoparmelia and confirm the use of ITS for accurately identifying species in this group.

Highlights

The taxonomic status of the genus Maronina and its phylogenetic relationships have been a matter of debate
Protoparmelia and Maronina s.l. are supported as sister groups, whereas Maronina australiensis is sister to the Protoparmelia-Maronina s.l. clade
The authors suggested Maronina s.str. to be a strictly Australian genus, comprising M. australiensis and M. hesperia only. We support this hypothesis, based on molecular evidence, which confirms that M. australiensis and M. multifera are not closely related

Summary

Introduction

The taxonomic status of the genus Maronina and its phylogenetic relationships have been a matter of debate. Kraichak et al (2017) suggested the use of a temporal banding approach for a consistent grouping of taxa at higher taxonomic levels, i.e. at family and genus level, for lichen-forming fungi. This approach identifies a divergence time of ~102–112 Ma for families and 29–33 Ma for genera (Kraichak et al 2017). A recent study aimed at molecular identification of species in Maronina and Protoparmelia, based on a multilocus dataset and species delimitation analysis, included these six species and two putatively novel species (Singh et al 2015). We include the type specimen M. australiensis, which has not been sequenced before

Materials and methods

Molecular methods

Results and discussion

Taxonomic conclusions