# Dicranum motuoense (Bryophyta): A New Taxon from China, with Special References to Its Complete Organelle Genomes

## TL;DR

A new moss species, Dicranum motuoense, is discovered in China, and its complete chloroplast and mitochondrial genomes are sequenced to better understand its evolution and diversity.

## Contribution

The discovery of a new moss species and the sequencing of its complete organellar genomes provide insights into Dicranum taxonomy and evolution.

## Key findings

- Dicranum motuoense is a newly identified species with unique morphological traits.
- The chloroplast and mitochondrial genomes of D. motuoense are 123.94 kb and 105.77 kb in length, respectively.
- The study includes a key for identifying Dicranum species with fragile leaves.

## Abstract

Dicranum is one of the most diverse and widespread genera within the family Dicranaceae, encompassing ca. 110 accepted species worldwide. However, the taxonomy of this genus remains notoriously complex, with the circumscription of several species still unresolved, thereby limiting our understanding of the Dicranum’s diversity. During a recent survey of Dicranum in China, we found an intriguing species characterized by a unique combination of morphological traits including stiff and fragile leaves, sharply denticulate leaf apices, elongated, rectangular and porose laminal cells throughout, bistratose or partially bistratose laminal cells in the distal part, 1–2 stratose alar cells, and a transverse section of the costa in the lower portion of leaf with two stereid bands and undifferentiated epidermal layers. Morphological and molecular phylogenetic analyses, based on five chloroplast markers and one nuclear marker, support the recognition of this moss as a new species, which we described here as Dicranum motuoense sp. nov. Furthermore, we present the complete organellar genomes of this newly identified species. The chloroplast genome of D. motuoense is 123.94 kb in length, while the mitochondrial genome is 105.77 kb in length. A total of 127 genes and 66 genes were identified in the chloroplast and mitochondrial genomes, respectively. This study not only advances our understanding of species diversity with Dicranum but also contributes to the broader knowledge of its evolution. Additionally, a key for the identification of Dicranum species with fragile leaves is included.