British Bryological Society Expedition to Mulanje Mountain,Malawi 2. Checklist of Malawi bryophytes

Abstract

A checklist of all bryophytes identified from Malawi at May 1991 is presented, with synonyms and references. The list is derived from literature and unpublished collections, and contains 197 mosses and 106 hepatics. The checklist was produced to provide a basis for describing plants new to Malawi, particularly for the British Bryological Society Expedition to Mulanje Mountain, Malawi in 1991. Distribution information is included, and the species accounts include published references and collection numbers where known. All information is held on a computer database.     

British Bryological Society Expedition to Mulanje Mountain,Malawi 3. Erpodiaceae (Musci)

Abstract

Four members of the moss family Erpodiaceae, Aulacopilum trichophyllum, Erpodium beccarii, E. coronatum and E. grossirete, collected during the 1991 British Bryological Society expedition to Mulanje Mountain, are recorded as new for Malawi.     

Genetic structure of mosses Pleurozium schreberi (Willd. ex Brid.) Mitt. and Racomitrium lanuginosum (Hedw.) Brid. along altitude gradients in Hokkaido,Japan

Abstract

The families Pterigynandraceae and Rigodiaceae are reviewed for Africa with reference to the collections made by the BBS Expedition to Mt Mulanje, Malawi in 1991. The single African species of Rigodium (Rigodiaceae) is reported to be quite frequent on Mt Mulanje, and three of the four species of Trachyphyllum (Pterigynandraceae) found in Africa (T. gastrodes, T. dusenii and T. inflexum) are reported, the latter two for the first time from Malawi. On present limited evidence, Malawi seems to be a centre of diversity of the genus.     

Recent Bryological Literature, 68

Abstract

Five species of Colura are reported from Mulanje Mountain, of which four, C. ealyptrifolia (Hook.) Dum., C. digitalis (Mitten) Steph., C. hattoriana Pócs and C. tenuicornis (Evans) Steph. are new for Malawi. C. hattoriana is also reported new for mainland Africa. A key to sub-Saharan taxa is provided.     

New records of bryophytes from the Canary Islands

Abstract

Two members each of the Adelanthaceae and Schistochilaceae and three of the Porellaceae are recorded from Mulanje Mountain, of which Adelanthus lindenbergianus (Lehm.) Mitt., Porella abyssinica (Nees) Trev. var. hoehnelii (Steph.) Pócs, Porella capensis (Gott.) Mitt. and P. subdentata (Mitt.) Steph. are first records for Malawi.     

Tropical African cedars (Widdringtonia, Cupressaceae): systematics, ecology and conservation status

Phenetic analyses of 24 morphological characters, collected in the field for 150 trees of Widdringtonia in Malawi, Zimbabwe, Mozambique and northern South Africa, show two distinct clusters. One can be identified as W. whytei , a tall, wide-crowned forest tree endemic to Mt Mulanje in Malawi, while the other is W. nodi/bra , a multi-stemmed shrub or narrow-crowned tree, which is common on Mulanje and widespread in southern Africa. These two sympatric species are distinct on phenetic, phylogenetic, ecological and biological grounds. The distinguishing characters of the two species are analysed and discussed and the differences are related to different responses to fire. Widdringtonia whytei is a forest pioneer with limited fire survival ability, while W. nodiflora coppices after fire and is common in fire-prone heathlands. To date it has been assumed that there is a single species of Widdringtonia on Mt Mulanje, and this has led to faulty management and exploitation decisions. Extensive plantations of the economically useless W. nodiflora have been established, in the belief that they are the economically desirable Mulanje cedar, W. whytei , which is now in danger of extinction.     

Kniphofia monticola (Liliaceae), a new species from Malawi

Kniphofia monticola Blackmore sp. nov., from Mulanje Mountain in Malawi is described. This new species is most closely related to K. splendida E. A. Bruce, a widely distributed species in tropical and southern Africa.     

Neglected refugia of biodiversity: mountainous regions in Mozambique and Malawi yield two novel freshwater crab species (Potamonautidae: Potamonautes)

Phylogenetic relationships amongst the southern African freshwater crab fauna are reinvestigated following the recent collection of morphologically distinct Potamonautes specimens from remote mountainous regions in Malawi and Mozambique. Specimens were subjected to DNA sequencing of three mtDNA loci, cytochrome c oxidase subunit I (COI), 12S rRNA, and 16S rRNA and compared to the 14 described species from the region. Phylogenetic analysis using maximum parsimony and Bayesian inference revealed the presence of two novel evolutionary lineages. The phylogeny demonstrates that Potamonautes obesus (A. Milne‐Edwards, 1868) is sister to a morphologically distinct novel species from Mount Namuli in Mozambique. Two sympatric and genetically distinct species from Mount Mulanje, in Malawi (forms A and B) were recognized. Form B is sister to the large‐bodied South African riverine freshwater crabs and represents a novel lineage whereas the remaining species (form A) from Mulanje, in Malawi was sister to samples from Mounts Inago and Mabu, and in Mozambique was identified as Potamonautes choloensis (Chace, 1953). The two novel evolutionary lineages were genetically distinct and morphologically different from the described species in each of the respective regions. Two new freshwater crab species Potamonautes namuliensis sp. nov. and Potamonautes mulanjeensis sp. nov. , are described in the present study. The samples from Mount Mulanje in Malawi, and Mounts Mabu and Inago in Mozambique represent new distribution records for Potamonautes choloensis. © 2012 The Linnean Society of London, Zoological Journal of the Linnean Society, 2012, 164 , 498–509.     

第六次北极科学考察海洋沉积物可培养细菌的多样性分析

【目的】研究北极海洋沉积物可培养细菌的菌种资源多样性。【方法】采用海水Zobell2216E培养基和涂布平板法对第六次北极科学考察获得的海洋沉积物开展细菌分离培养,通过16S rRNA基因系统发育分析了解可培养细菌的多样性。【结果】根据菌落形态特征,从40个站位的北极海洋沉积物样品中共分离并获得16S rRNA基因有效序列的细菌达445株;基于16S rRNA基因的相似性分析与系统发育研究结果表明,分离获得的细菌分属于细菌域的4个门、6个纲、13个目、28个科、49个属、91个种,其中γ-Proteobacteria占大多数;有12株与模式菌株的16S rRNA基因序列相似性小于97%,可能代表了6个潜在的细菌新物种;此次获得的细菌种类组成与以往第五次北极科考获得的相比,在属水平上差异较大。【结论】北极海洋沉积物中存在着丰富的微生物菌种资源,具有很多新型微生物仍未被发现,是亟待开发的微生物资源宝库。     

British Bryological Society Expedition to Mulanje Mountain,Malawi. 17 Sematophyllaceae (Bryopsida): Part 1

Abstract

The family Sematophyllaceae is a difficult family to treat in Africa because of the large number of species described without any subsequent revision or monography and, despite the many collections mentioned in this paper, only two species had previously been identified from Malawi. A total of four species in four genera (Gammiella, Mρacrohymenium, Radulina and Wijkia) are recorded in this paper, all but one new to Malawi. The two remaining genera (Sematophyllum and Trichosteleum) present additional difficulties of identification, and will be dealt with separately.     

Studies on high altitude saxicolous-Cyanophyta XI - On the morphology of Petalonema borzii sp. nov.

Abstract

The morphology of a new species of Petalonema Berk collected under a saxicolous habitat at 2900 m above sea level in the Singalila Range, Eastern Himalayas, during the Botanical Expedition of May 1974, was critically studied and named as Petalonema borzii sp. nov. The same alga was collected again on 28 Nov. 1982 from the Singalila Range at an altitude of 2500 m above sea level.     

Germination response and viability of an endangered tropical conifer Widdringtonia whytei seeds to temperature and light

The tropical conifer Widdringtonia whytei Rendle is an endangered species endemic to Mulanje Mountain in Malawi. A study was conducted for the first time under controlled conditions in order to assess the effects of temperature and light on germination and viability of W. whytei seeds. Seeds incubated at a constant temperature of 20 °C attained the highest cumulative germination percentage (100%) followed by 87% germination under fluctuating temperatures of 15 °C night/25 °C day. No seed germination occurred at temperatures below 15 °C. Seeds that failed to germinate at temperatures below 15 °C showed the highest (> 90%) viability compared to the seeds incubated at 25 °C (60%). Across temperature regimes, germination was significantly higher under light (44.7%) than dark (35.6%) conditions. It is concluded that temperature is one of the critical factors for germination of W. whytei seed. The ability of W. whytei seeds to germinate both in light and darkness implies that the species would unlikely form a persistent soil seed bank, an attribute which is common in species that survive in habitats frequently disturbed by fires.     

AN ASSESSMENT OF THE GROWTH RATE OF MPASA,OPSABIDIUM MICROLEPIS (GUNTHER, 1864) (PISCES: CRYPRINIDAE), BY LENGTH FREQUENCY ANALYSIS

SUMMARY

The mpasa, Opsaridium microlepis, is an important commercial species in areas of Lake Malawi near major inflowing rivers during annual spawning migrations. Plots of length frequency data collected over a series of years from mpasa catches in the Bua and North Rukuru Rivers show consistent peaks and these are believed to represent year classes. Growth in length is approximately linear, about 11 cm per year, until about five years of age. Males and females have similar growth rates.

Catch per unit effort is positively related to river level at time of sampling, and to river levels in earlier years, thus high river levels improve recruitment.     

Collection and evaluation of pearl millet (Pennisetum) germplasm from Malawi

A germplasm collecting trip to Malawi was launched during March/April 1979, resulting in the collection of 260 traditional cultivars of pearl millet (Pennisetum americanum), 11 intermediate forms, and 6 accessions of wild Pennisetum. Most of the cultivated pearl millet samples were obtained from the hot lowlands of the lower Shire Valley, with a few samples from the cool highlands of Mulanje and Mangochi. A mixture of different types that varied in plant height, maturity, and spike characters were observed in farmers’ fields. In the south, early types with loose, thin, cylindrical spikes and in the north, late-maturing types producing many tillers with stout spikes having long bristles were found. The grain is used to prepare a thick porridge, nsima, or to brew local beer, chimera. When the collection was evaluated at ICRISAT Center, Patancheru, considerable variation was observed for days to 50% flowering and plant height, but not for spike and grain characters. During the rainy season, the majority of the accessions flowered early (70 days), grew very tall (250 cm), and produced thin (22 mm), short (22 cm) spikes with small, obovate to elliptical, corneous grey grain. In the postrainy season, most of the accessions flowered a week earlier accompanied by reduction in plant height. Millet germplasm from Malawi belongs to the race typhoides and serves as a good source of genes for earliness, tillering, and corneous endosperm.     

基于生态安全格局的山水林田湖草生态保护修复优先区识别——以四川省华蓥山区为例

优先区识别,是科学有序推进山水林田湖草生态保护修复工作的重要基础。以山水林田湖草生态保护修复工程之一的四川华蓥山区为例,基于生态系统服务重要性提取生态源地共1392.63 km²,占华蓥山区总面积的35.60%;结合土地覆被类型与地质灾害敏感性构建生态阻力面,并利用最小累积阻力模型与电路模型提取生态廊道共84条,夹点区域0.1 km²,含夹点廊道10条;生态保护优先区主要分布在景观破碎化较为严重的广安区境内,以及华蓥山西南端的夹点廊道。以生态修复模拟方法识别障碍点,确定生态修复优先区93.86 km²,大致分两片。其中,广安区境内受到人类活动干扰的破碎化生态空间,主要生态修复策略为植被恢复与退耕还林;华蓥山、铜锣山、明月山等滑坡、泥石流地质灾害频发区,主要生态修复策略是矿山地质修复与植被恢复。本研究提出生态安全格局构建与生态修复模拟的思路,为山水林田湖草生态保护修复工作提供了可行的定量方法。     

Fissidens monguilloni Thér. in England

Abstract

The 1996 Chagos Expedition provided an opportunity to study the archipelago's bryophyte flora: 25 of the 55 islands were ecologically investigated, some in more detail than others, and lists and representative collections of mosses, hepatics and other cryptogamic plants were assembled for many of them. Although the islands have a low biodiversity for most of these groups, as would be expected in terms of their relatively young age, remoteness and small terrestrial surface areas, those organisms that are present are often found in abundance and play significant ecological roles. Where the status of taxa on islands has been determined, there appears to be a good correlation between bryophyte biodiversity and island size. Epiphytic bryophytes were not host specific and no epiphyllous species was observed. Biogeographic details are provided, where possible, for the 19 taxa recorded, of which four are new to the Indian Ocean and seven are new to the Chagos Archipelago. A new taxon, Cololejeunea planissima var. chagosensis Pócs var. nov. is described, and notes and illustrations of a probably new Lejeunea species are provided.     

Lichens of Barla Mountain in Isparta,Turkey: Diversity study and ecological assessment of the area

This study reports on 230 infrageneric lichenized and lichenicolous taxa from Barla Mountain, Isparta, Turkey and assesses the ecological features of the area using the distribution of the lichens in the region and their poleophoby and solar irradiation ecological indicator values. One lichenized fungus, Protoblastenia terricola, and one lichenicolous fungus, Zwackhiomyces dispersus, are recorded as new in Turkey and 194 taxa are reported for the first time from Barla Mountain. After this research, number of the lichenized and lichenicolous fungi taxa of Barla Mountain rose to 241. Based on assessments using the ecological indicator values, the area is dominated by natural or semi-natural and well-preserved habitats.     

Elevated mtDNA diversity in introduced populations of Cynotilapia afra (Günther 1894) in Lake Malawi National Park is evidence for multiple source populations and hybridization

Genetic variation in many invasive species shows little or no signs of a founder event, suggesting that high genetic diversity may facilitate establishment success. The rocky‐shore, plankton‐feeding cichlid fish Cynotilapia afra is endemic to Lake Malawi, but naturally absent from many suitable sites. In the 1960s, this species was introduced to the southern areas of the lake, presumably as a result of the aquarium fish trade. It has now become established on a number of rocky areas within the Lake Malawi National Park. Here, we analysed DNA sequence variation in the mitochondrial control region of six native and four introduced populations of C. afra, and three populations of the closely‐related and hybridizing Pseudotropheus zebra. In contrast to previous studies of Lake Malawi rock dwelling cichlids, network analyses suggested that native populations of C. afra showed high levels of lineage sorting in mtDNA. Introduced populations showed higher sequence and haplotype diversity than their native counterparts. Our analyses suggested that the elevated gene diversity was largely attributed to the fact that the introduced C. afra populations were derived from several genetically distinct and geographically separate populations, and to a lesser extent because of introgressive hybridization with native P. zebra. The establishment and spread of C. afra may be partly because of its ability to occupy a vacant ecological niche, but it may also have been facilitated by its enhanced genetic diversity.     

An ecological study of the relationship between two living fossils in Malawi: the Mulanje Tiger Moth (Callioratis grandis) and the Mulanje Cycad (Encephalartos gratus)

The Mulanje tiger moth (Callioratis grandis) has recently been discovered feeding solely on the Mulanje Cycad, Encephalartos gratus. In its type locality Encephalartos gratus is severely threatened through habitat destruction and human population growth. As a result the first detailed demographic survey of Encephalartos gratus on Mount Mulanje was undertaken with particular emphasis on the relationship between E. gratus and Callioratis grandis. What is unusual about C. grandis is that the males exhibit lekking behaviour, for which aposematism may be a prerequisite. Cycads were surveyed in a systematic manner. Both the biotic and abiotic parameters were recorded from 532 wild Encephalartos gratus. Results showed the morphological range of measurements differed from that of previously published literature on this species. Results also showed that the incidence of Callioratis larval damage was related to the maturity of the wild cycads – moth damage was greater on more mature plants. Approximately 50% of surveyed cycads showed evidence of Callioratis moth damage, however, there was no apparent preference from the moth to select either male or female cycads as food plants for the larvae. In some cases there was severe damage to cycad fronds, but this did not seem to affect the production of reproductive cones or even the survival of individual cycads.