Need for split: integrative taxonomy reveals unnoticed diversity in the subaquatic species of Pseudohygrohypnum (Pylaisiaceae, Bryophyta)

On the Cryptic Speciation in the Mosses with East Asia-East North America Disjunction: A Case Study of Two Poorly Understood Mosses from the Southern Extremity of the Russian Far East

A survey of the moss flora of the southernmost part of the Russian Primorsky Territory yielded several intriguing taxa, whose identity is assessed herein based on an integrative morpho-molecular approach. Bellibarbula recurva was previously known in inland Asia only from the Sino-Himalayan region and the new locality is distant from the earlier known ones to ca. 3000 km. Despite the morphological uniformity, Russian specimens are remarkably distinct in sequences of all three obtained DNA markers, approaching an American specimen in the rps4 sequence. Another probable relic, Symblepharis cf. crispifolia, appeared to be fairly common in the southern part of the Primorsky Territory, where low mountains are covered with hard-leaved forests. Russian specimens of Symblepharis cf. crispifolia var. brevipes show significant divergence from S. crispifolia s.str., which also has complex phylogenetic structure, obscuring further taxonomic implications. The description and illustrations of both taxa based on Russian specimens are provided, and the area, where both species occur, is briefly characterized; it includes numerous thermophilous species, which are rare or do not occur northwards. Our case study uncovers the problem of cryptic speciation within species distributed in temperate climate and is considered to represent relics of Arcto-Tertiary flora.

Integrative Taxonomy Reveals Hidden Diversity in the Aloina catillum Complex (Pottiaceae, Bryophyta)

Aloina catillum is a variable moss typical of xerophytic environments in the Neotropics, characterized against other closely allied Aloina species with well-differentiated leaf border by its setae twisted to the left throughout. In order to clarify its variability and its relationships with the allied species with differentiated leaf border A. brevirostris, A. obliquifolia, and A. rigida, we performed an integrative study including sequence data from four markers (nuclear ITS, plastid atpB-rbcL, trnG, trnL-F), morphometry, and species assembling by automatic partitioning (ASAP) algorithm. Our data suggest that A. catillum consists of at least three species: A. calceolifolia (an earlier name for A. catillum), and two species described here as a new, A. bracteata sp. nov. and A. limbata sp. nov. This latter species includes the specimens previously identified as A. obliquifolia from South America. Additionally, some morphological and molecular variability was also detected in A. limbata, but was not consistent enough to be recognized taxonomically. The study supports the presence of A. brevirostris in the Neotropics and A. rigida is tentatively excluded from South America. Full descriptions of the A. catillum s.l. species and a diagnostic key to this complex in South America are provided.

New Taxonomic Arrangement of Dicranella s.l. and Aongstroemia s.l. (Dicranidae, Bryophyta)

The recent molecular phylogenetic study of the families Aongstroemiaceae and Dicranellaceae, which resolved the genera Aongstroemia and Dicranella as polyphyletic, indicated the need for changes in their circumscription and provided new morphological evidence to support the formal description of newly recognized lineages. Following up on these results, the present study adds another molecular marker, the highly informative trnK-psbA region, to a subset of previously analyzed taxa and presents molecular data from newly analyzed austral representatives of Dicranella and collections of Dicranella-like plants from North Asia. The molecular data are linked with morphological traits, particularly the leaf shape, tuber morphology, and capsule and peristome characters. Based on this multi-proxy evidence, we propose three new families (Dicranellopsidaceae, Rhizogemmaceae, and Ruficaulaceae) and six new genera (Bryopalisotia, Calcidicranella, Dicranellopsis, Protoaongstroemia, Rhizogemma, and Ruficaulis) to accommodate the described species according to the revealed phylogenetic affinities. Additionally, we amend the circumscriptions of the families Aongstroemiaceae and Dicranellaceae, as well as the genera Aongstroemia and Dicranella. In addition to the monotypic Protoaongstroemia that contains the newly described dicranelloid plant with a 2-3-layered distal leaf portion from Pacific Russia, P. sachalinensis, Dicranella thermalis is described for a D. heteromalla-like plant from the same region. Fourteen new combinations, including one new status change, are proposed.