Multilocus-phylogeny of the lichen-forming genus Bacidia s. str. (Ramalinaceae, Lecanorales) with special emphasis on the Russian Far East

Abstract

To clarify deep relationships among species lineages within Bacidia s. str., and to investigate the robustness of the deeper branches, we combined data from three traditionally used RNA-coding genes (nrITS, nrLSU and mtSSU) with two protein-coding genes (RPB1 and RPB2). The multigene phylogeny contained 48 newly generated sequences from the Russian Far East and all Bacidia s. str. sequences from GenBank (131 sequences). We subjected the alignments for the single and concatenated data sets to Bayesian inference (BI) and two maximum likelihood (ML) analyses (RAxML and IQ-TREE). The topologies of phylogenetic trees recovered from BI and ML analyses were highly concordant. The multilocus phylogeny of Bacidia s. str. was congruent with previous results based on nrITS sequences from the Russian Far East but with considerably higher support values for most of the deeper branches. A correlation between the recovered clades and apothecial pigments in the upper part of the hymenium and lateral exciple was observed. Based on morphological and molecular evidence, Bacidia obtecta is described as new to science. It was recovered as the sister lineage of B. elongata. The two species are alike in having up to four enlarged lumina cells along the exciple edge, but B. obtecta differs in the abundant crystals found in the upper hymenium and lateral exciple, and by having spores with fewer septa.

High diversity of Bacidia (Ramalinaceae, Lecanorales) species in the Caucasus as revealed by molecular and morphological analyses

“…The main groups obtained from single and concatenated data in both ML and BI analyses are congruent and correspond to those obtained from the previous phylogenies (Ekman 2001;Gerasimova et al 2018Gerasimova et al , 2021b. Furthermore, similar to previous results, our phylogenies revealed two highly supported major clades in the two-and three-locus phylogenies.…”

“…with BSr ≥ 70%, PP ≥ 0.95 and BSi ≥ 80%). However, in the multilocus trees poor support was retrieved for the sister relationship of the Suffusa and Heterochroa groups (BSr/PP/ BSi: 62/0.92/65, and 71/0.94/72), the subclades of the Schweinitzii group (not present in the Caucasus, discussed in detail in Gerasimova et al (2021b)), the position of the Bacidia rubella s. str. clade (BSr/PP/BSi: 72/0.55/66, and 54/-/ 37), the placement of B. inconspicua ined.…”

“…In line with previous studies, we retrieved two large clades: Clade I includes the Laurocerasi, Schweinitzii and Suffusa groups, as well as the newly defined Heterochroa group (that consists of representatives from the Caucasus), and Clade II includes the Rubella, Polychroa and Arceutina groups. In a previous work, phylogenies mainly included specimens from temperate regions (Gerasimova et al 2021b), while in this study, we also included and Bagliettoa-green), or a combination thereof, in the upper part of the hymenium and lateral exciple. The herein-defined Heterochroa group from the Caucasus also supports this differentiation; the Caucasian specimens are characterized by a dark purplish epithecium corresponding to the type specimen of B. heterochroa.…”

“…To confirm the relationship between North American, Far Eastern and Caucasian representatives, we included several specimens from different parts of the Caucasus in our phylogeny (Table 1 (Gerasimova et al 2021b). Intriguingly, in our analyses, the newly sequenced Caucasian specimens of B. suffusa form a clade with the North American individuals that is sister to the Far Eastern B. suffusa clade.…”

A new species and four new records of Bacidia (Lecanorales, Ramalinaceae) from South Korea, with a key to Korean species

“…2 ). Bacidia suffusa was previously detected from North America, North Caucasus, Russian Far East and Pakistan, but rare or absent in Europe ( Otte 2007 ; Gerasimova et al 2018 , 2021 ; Adrees et al 2022 ). This is a new record to Korea.…”