Bryum atrovirens Brid. complex (Bryaceae, Bryophyta) of China, including a new species record

Abstract

The Bryum atrovirens Brid. complex in China was critically revised based on morphological evidence, with a focus on the tubers. The aim of the study is to clarify the morphological delimitation, and geographical distribution for each recognized species of this complex in China. The results show that: (1) Nine species are recognized for the complex in China, namely B. apiculatum Schwägr., B. atrovirens Brid., B. bornholmense Wink. & R. Ruthe, B. clavatum (Schimp.) Müll. Hal., B. radiculosum Brid., B. rubens Mitt., B. sauteri Bruch & Schimp., B. stellituber Arts and B. tuberosum Mohamed & Damanhuri. B. stellituber represents a new record for China, whereas sporophytes are for the first time recorded in two populations of the new record, and the rhizoidal tubers of B. atrovirens and B. rubens are first documented from Chinese material. (2) Species of the B. atrovirens Brid. complex are ‘ephemeral’ colonists adapted to the exploitation of short-lived habitat gaps. Asexual reproduction by means of tubers was observed to be common and numerous. Identification of species within the complex relies heavily on the tuber characteristics, including its distribution (along short or long rhizoids, clustered or not), color, shape, size, cell wall thickness, presence of surface protuberance, and degree of protuberance when present. (3) The distribution at global and Chinese provincial levels for each species is summarized. An identification key to species of the B. atrovirens Brid. complex in China is presented. In conclusion, the species identification of the B. atrovirens Brid. complex can be rapidly accomplished based on the morphological characteristics exhibited by the tuber. The species newly record adds data for the moss in China.

Keywords

• bryum stellituber arts
• tubers
• bryum
• new record
• taxonomy