Faculty of Agriculture and Life Science, Hirosaki University, 3 Bunkyo-cho, Hirosaki, Aomori 036-8561, Japan.
Mycologia. 2010 May-Jun;102(3):729-46. doi: 10.3852/09-230.
Massarina ingoldiana occurs worldwide on a variety of dead plant substrates in aquatic habitats. This species has been accommodated in Massarina or Lophiostoma in Pleosporales, Dothideomycetes, but the validity of either of these taxonomic placements has not been confirmed with molecular data. In addition morphological variations occur among different populations of this species causing problems in identification. To evaluate the generic placement and monophyly of M. ingoldiana and the taxonomic usefulness of variable morphological features, phylogenetic analyses based on SSU and LSU sequences of ribosomal DNA were conducted for 10 putative strains of this species and its relatives. Phylogenies revealed that M. ingoldiana sensu lato is polyphyletic and comprises two distinct lineages within Pleosporales. Neither lineage was congeneric with either Massarina or Lophiostoma. Based on molecular data and a reevaluation of morphology, two new genera, Lindgomyces and Tingoldiago, are established for the two lineages of M. ingoldiana sensu lato. Lindgomyces includes four species, L. ingoldianus comb. nov. (= M. ingoldiana sensu stricto), L. rotundatus sp. nov. (= M. ingoldiana sensu lato), L. cinctosporae sp. nov. and L. breviappendiculatus comb. nov. (= Lophiostoma breviappendiculatum). A new aquatic family, Lindgomycetaceae, is proposed for Lindgomyces and its sister taxon, Massariosphaeria typhicola. Isolates of a fungus from submerged Phragmites, with ascospores similar to those of M. ingoldiana, occurred in an additional single species lineage distant from that of M. ingoldiana (Lindgomyces). This fungus is described as Tingoldiago graminicola gen. & sp. nov. The discovery that Tingoldiago, which occurs in a lineage distantly related to Lindgomyces but has morphologically similar ascospores and ascospore sheaths, suggests that the elaborate ascospore sheath in M. ingoldiana has arisen in two separate lineages as a result of convergent evolution in response to the aquatic environment. The large gelatinous sheath previously was considered one of the most distinctive and stable features for species identification of M. ingoldiana.
麦粒赤霉广泛存在于水生栖息地各种死亡植物基质上，遍布全球。麦粒赤霉菌在 Pleosporales，Dothideomycetes 中被归入 Massarina 或 Lophiostoma 中，但这些分类群的有效性尚未通过分子数据得到证实。此外，该种不同种群之间存在形态变异，导致鉴定困难。为了评估麦粒赤霉菌的属的位置和单系性，以及可变形态特征的分类学用途，对该种的 10 个假定菌株及其亲缘种进行了核糖体 DNA 的 SSU 和 LSU 序列的系统发育分析。系统发育分析表明，广义麦粒赤霉菌是多系的，包含 Pleosporales 中的两个不同谱系。这两个谱系与 Massarina 或 Lophiostoma 都没有同源关系。基于分子数据和形态学的重新评估，建立了两个新属，Lindgomyces 和 Tingoldiago，用于广义麦粒赤霉菌的两个谱系。Lindgomyces 包括四个种，L. ingoldianus comb. nov.（=麦粒赤霉菌）、L. rotundatus sp. nov.（=麦粒赤霉菌）、L. cinctosporae sp. nov. 和 L. breviappendiculatus comb. nov.（= Lophiostoma breviappendiculatum）。为了包括 Lindgomyces 及其姐妹分类群 Massariosphaeria typhicola，提出了一个新的水生科 Lindgomycetaceae。从水下的芦苇中分离到的一种真菌，其分生孢子类似于麦粒赤霉菌，出现在与麦粒赤霉菌（Lindgomyces）不同的单独种谱系中。这种真菌被描述为 Tingoldiago graminicola gen. & sp. nov.。Tingoldiago 的发现表明，它与 Lindgomyces 没有亲缘关系，但具有形态相似的分生孢子和分生孢子鞘，这表明麦粒赤霉菌复杂的分生孢子鞘是由于对水生环境的趋同进化而在两个不同的谱系中产生的。以前认为，大的胶状鞘是识别麦粒赤霉菌的最具特色和最稳定的特征之一。
