Mawenzhangia thamnobryoides: A new species of Moss from Shangri-la.

Mosses (Bryophytes) are simple plants which lack vascular systems to pump water and nutrients from a root system, instead relying on what they can absorb through their leaves, and generally only reaching a few cm in height. This means that they are at their most diverse in moist habitats, though some species are surprisingly drought-tolerant. Despite their simple nature, Mosses are an important part of ecosystems the world over, creating a water-holding layer which covers soil, rocks, trees and some animals, inside which entire miniature communities of organisms thrive. Mosses also differ from vascular plants in that they are haploid (have one set of chromosomes) rather than diploid (have paired chromosomes); though they have a diploid spore stage used to propagate the species in the same way that the (haploid) pollen of vascular plants is.

In a paper published in the journal Phytotaxa on 6 April 2018, Johannes Enroth of the Department of Biological Sciences and Botany Unit at the Finnish Museum of Natural History, James Shevock of the Department of Botany at the California Academy of Sciences, and Michael Ignatov of the Main Botanical Garden of the Russian Academy of Sciences, describe a new species of Moss from the Niru River watershed in the Hengduan Mountains of Shangri-la County in Yunnan Province, China.

The Hengduan Mountains form the southeastern tip of the Himalayas, stretching from eastern Sichuan Province through northern Yunnan and southeaster Tibet into southern Myanmar. The range comprises a series of parallel north-south mountain ridges with south-flowing rivers between. The area is considered to be one of the world's biodiversity hotspots, with sharp divisions in flora and fauna both between the valleys of the range and at different altitudes on the mountains, leading to a very high number of endemic species.

The new species is placed in a new genus, Mawenzhangia, named in honour of Wen Zhang Ma, the Curator of Bryophytes at the Kunming Institute of Botany, and given the specific name thamnobryoides, in reference to the thickened dendroid erect shoots and branches of younger plants. The species was found growing on metamorphic boulders along the banks of the Niru River in a Pine/Oak forest. The individual plants grow up to 5 cm in height, and are yellowish green or brownish-grey and slightly glossy, with branching fronds.

 Mawenzhangia thamnobryoides. (1)−(2) Habit. (3) Portion of flagelliform branch. (4) Portion of leafy flagella. (5) Portion of leaf stipe. (6)−(8) Main branch leaves. (9)−(10) Secondary branch leaves. (11)−(12) Stipe leaves. (13) Perichaetium. (14) Inner perichaetial leaf. (15) Innermost perichaetial leaf with archegonia. (16) Perigonium. (17) Inner perigonial bract. (18) Innermost perigonial bract with antheridia. Scale bars: (a) 0.5 cm (3); (b) 1 mm (14)−(15), (17)−(18); (c) 1 mm (11)−(12); (d) 1 cm (1)−(2) and 1 mm (13), (16); (e) 1 mm (6)−(10); (f) 1 mm (5); (g) 100 μm (4). Enroth et al. (2018).

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Hoolock tianxing: A new species of Hoolock Gibbon from China and Myanmar.

Gibbons, Hylobatidae, are small Apes found across East, South and Southeast Asia. There are currently 19 species of Gibbons divided into four genera. Hoolock Gibbons, Hoolock spp., also known as Hoolocks or White-browed Gibbons, are found in the northwestern part of this total range, across parts of northeast India, Bangladesh, Myanmar and Yunnan Province, China. They are distinguished from other Gibbons by a number of genetic and morphological features, but most obviously by the presence of the distinctive white eyebrows that give the group its common name. The genus is currently split into two species, living on either side of the Chindwin River in Myanmar. Major rivers commonly provide barriers between Gibbon species, not simply because Gibbons cannot swim, but because the type of trees in river basins are not suitable environments for Gibbons. This has led to speculation that other river valleys may form barriers between undetected Gibbon species.

In a paper published in the American Journal of Primatology on 10 January 2016, a team of scientists led by Peng-Fei Fan of the School of Life Sciences at Sun Yat-sen University and Institute of Eastern-Himalaya Biodiversity Research at Dali University, describe a new species of Hoolock Gibbon from eastern Myanmar and southwestern China.

The new species is named Hoolock tianxing, where 'tianxing' means 'Skywalker' in Chinese, in reference to the unique brachiating motion of Gibbons. It was identified by morphological and genetic examination of museum specimens and living animals bred in Zoos and confiscated from smugglers, as well as photographs of wild animals and genetic material from stool specimens collected from the wild. In keeping with current Chinese law and the ethical guidelines of the American Society of Primatologists, no live animals were killed or collected during the study.

The new species can be distinguished on a number of morphological characteristics, but most obviously their fur, which is brown in the males and yellow in the females, with the white eyebrows of the males thinner and more widely spaced than in any other species and that of the females downturned and with more white between the eyes than any other species.

Male Hoolock tianxing. Fan et al. (2016).

The species was found in the areas between the Nmai Hka and Salween rivers (tributaries of the Irawady) in parts of Shan, Kayah and Kayin states in Myanmar and Yunnan Province in China. This area around Mount Gaoligong in the westernmost part of the Hengduan Mountain Chain, an extension of the Himalayas. This population has previously been thought to belong to the species Hoolok leuconedys, (the Eastern Horlook), which is considered to be Vulnerable under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species, with an estimated population of 310 000–370 000 individuals. However the new species has a much more limited range and consequently a lower population. In addition it is subject to illegal hunting and destruction, degradation and fragmentation of its habitat throughout its range. It is estimated that about 200 of these Gibbons survive in China, with around 50 000 in Shan State in Myanmar and about 16 000 in Kayah and Kayin States. For this reason the new species is assessed to be Endangered under the terms of the Red List.

Female Hoolock tianxing. Fan et al. (2016).

Fan et al. also developed a genetic phylogeny for the new species, using mitochondrial genetic samples from 10 Gibbon species, two Gorilla species, two Chimpanzee species, two Orangutan species, three Macaque species, and Humans. This was given a chronological framework by the inclusion of fossil species thought to have been close to the branching points between modern lineages, namely Rukwapithecus fleaglei from the Miocene Nsungwe Formation of Tanzania, thought to be the oldest Great Ape fossil known, and the oldest Caterrhine (the group that includes Old World Monkeys and Great Apes) that can be placed in any modern group, Sivapithecus indicus from the Miocene Chinji Formation of Pakistan, which has been identified as a member of the Ponginae (the group that includes modern Orangutans), and Sahelanthropus tchadensis from the Late Miocene Nawata Formation of Toros Menalla in northern Chad, thought to be an Hominin (the group that includes modern Humans) that lived shortly after the split with the Chimpanzees. No fossil Gibbons were included in the study, as the relationships of the few fossil Gibbons known to modern Gibbons are far from clear. This study suggests that Hoolock tianxing split from its closest related species (Hoolok leuconedys) about 1.14 million years ago, in the Middle Pleistocene.

A juvenile male of Hoolock tianxing from Mt. Gaoligong jumping across trees. Lei Dong in Fan et al. (2016).

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Didymodon hengduanensis: A new species of Moss from the Hengduan Mountains of southwest China.

The Hengduan Mountains form the southeastern tip of the Himalayas, stretching from eastern Sichuan Province through northern Yunnan and southeaster Tibet into southern Myanmar. The range comprises a series of parallel north-south mountain ridges with south-flowing rivers between. The area is considered to be one of the world's biodiversity hotspots, with sharp divisions in flora and fauna both between the valleys of the range and at different altitudes on the mountains, leading to a very high number of endemic species.

In a paper published in the journal Phytotaxa on 21 September 2016, Juan Jiménez of the Departamento de Biología Vegetal (Botánica) at the Universidad de Murcia, David Long of the Department of Botany at the California Academy of Sciences, James Shevok of the Royal Botanical Garden iEdinburgh and Juan Guerra, also of the Departamento de Biología Vegetal (Botánica) at the Universidad de Murcia, describe a new species of Moss from the Hengduan Mountains of Sichuan and Yunnan provinces.

The new Moss is placed in the widespread and specious genus Didymodon, and given the specific name hengduanensis, meaning 'from Henduan'. The species is described from five specimens from Lushu, Heqing, Gongshan, and Shangri-la counties in Yunnan Province and Yajiang County in Sichuan Province, collected by Davd Long and James Shevock during a series of joint expeditions with the Chinese Academy of Sciences. The moss grows in dense tufts reaching 3.7 cm in height, and yellowish green in colour. It is distinguished from other Mosses in the genus Didymodon by its long, pointed leaves and by the presence of a leaf margin, made up of cells distinct from those of the rest of the leaf.

Habit of Didymodon hengduanensis in dry state. Jiménez et al. (2016).

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