Exceptional diversity of mouse lemurs (Microcebus spp.) in the Makira region with the description of one new species

Although the number of described lemur species has increased considerably over the last 20 years, detailed biogeographic data are still lacking from many geographic regions, in particular in the eastern part of Madagascar. This study investigated mouse lemur species diversity in a previously unstudied Inter-River-System in the eastern Makira region. Three sites were visited and 26 individuals were sampled and characterized with 13 external morphometric measurements. Standard phylogenetic analyses were performed on the basis of sequences of three mitochondrial loci by including representatives of all other published mouse lemur species for comparison. The analyses revealed the presence of three mouse lemur species in one study site, two of which were previously undescribed. The two new species are genetically distinct and belong to the larger-bodied mouse lemur species on the island, whereas the third species, Microcebus mittermeieri, belongs to the smaller-bodied mouse lemur species. The study fully describes one of the new species. This study and other lemur inventories suggest that the Makira region is particularly rich in lemur species and the lack of any protected zone in this area should now attract the urgent attention of conservation stakeholders.     

Maintenance of clinal variation for shell colour phenotype in the flat periwinkle Littorina obtusata

Clines can signal spatially varying selection and therefore have long been used to investigate the role of environmental heterogeneity in maintaining genetic variation. However, clinal patterns alone are not sufficient to reject neutrality or to establish the mechanism of selection. Indirect, inferential methods can be used to address neutrality and mechanism, but fully understanding the adaptive significance of clinal variation ultimately requires a direct approach. Ecological model systems such as the rocky intertidal provide a useful context for direct experimentation and can serve as a complement to studies in more traditional genetic model systems. In this study, we use indirect and direct approaches to investigate the role of environmental heterogeneity in the maintenance of shell colour polymorphism in the flat periwinkle snail, Littorina obtusata. We document replicated clines in shell colour morph frequencies over thermal gradients at two spatial scales, contrasting with patterns at previously reported microsatellite loci. In addition, experimental results demonstrate that that shell colour has predictable effects on shell temperature and that these differences in temperature, in turn, coincide with patterns of survivorship under episodic thermal stress. Direct manipulation of shell colour revealed that shell colour, and not a correlated character, was the target of selection. Our study provides evidence that spatially varying selection via thermal regime contributes to the maintenance of shell colour phenotype variation in L. obtusata in the sampled areas of the Gulf of Maine.     

The Madagascan genus <Emphasis Type="Italic">Vaughania</Emphasis> is reduced to synonymy under <Emphasis Type="Italic">Indigofera</Emphasis> (<Emphasis Type="Italic">Leguminosae-Papilionoideae-Indigofereae</Emphasis>)

Summary  Eleven species comprising the Madagascan genus Vaughania are subsumed within the large pantropical genus Indigofera. Six new combinations are made; the remaining species were originally described in Indigofera.     

The Edible Mushrooms of Madagascar: An Evolving Enigma

The Edible Mushrooms of Madagascar: An Evolving Enigma. This paper on the most significant edible wild mushrooms of Madagascar is organized in the following four categories: (1) mushrooms of introduced eucalypt plantations, (2) mushrooms of introduced pine plantations, (3) mushrooms of native forests and woodlands, and (4) mushrooms found in fields, agricultural waste and other altered, non–forest habitats. Eucalyptus robusta plantations yield by far the bulk of edible mushrooms that are sold, especially species of Russula and Cantharellus. Some Suillus species of northern hemisphere origin have been introduced with pine plantations and are locally important, forming the basis of a small canning industry. In native woodland areas on the central plateau, several ectomycorrhizal mushrooms—very similar to those on the African mainland—are collected and consumed. With the exception of the widely marketed Cantharellus platyphyllus ssp. bojeriensis, these are only of local importance in the villages and smaller markets of the area. Denser forests in the mountains or on the east coast as well as manmade habitats such as fields, pastures, and agricultural wastes are searched for saprobic mushrooms of various types. Some of these saprobic mushrooms show considerable potential for cultivation. The variety of ectomycorrhizal mushrooms found in eucalypt plantations is unprecedented outside of Australia and, for the most part, do not appear to be of Australian origin. Possible reasons for this are briefly discussed. Two economically important species, Russula prolifica sp. nov. and R. edulis sp. nov., are newly described.     

Coastal sponge communities of the West Indian Ocean: taxonomic affinities, richness and diversity

Sponges assemblages were sampled in four coastal study regions (Malindi, Kenya; Quirimba Archipelago, northern Mozambique; Inhaca Island, Southern Mozambique and Anakao, Madagascar) in the west Indian Ocean. Sponge species were counted in multiple 0.5 m² quadrats at depths of between 0 and 20 m at a number of sites within localities within each region. Despite the relatively small areas sampled, sponge samples comprised a total of 130 species and 70 genera of the classes Demospongiae and Calcarea. Sponges are clearly a major taxon in these regions in terms of numbers of species, percentage cover or biomass, although their ecology in the west Indian Ocean is virtually unknown. Nearly half of the genera, e.g. Iotrochota, found were species with a so‐called Tethyan distribution. Most of the other genera were cosmopolitan, e.g. Clathria, but some were cold water (Coelosphaera), Indo‐Australian (Ianthella) or circum‐African (Crambe). Many of the species encountered in the present study occurred in at least two study regions, many in more and could occupy large areas of substratum. Some of these, e.g. Xestospongia exigua, are commonly found throughout the Indo‐west Pacific region where they also occupy much space. The endemicity of the shallow water sponge faunas in East Africa (20–25%) seem to be high within the Indo‐Pacific realm but are lower than northern Papua New Guinea. The tropical regions (Kenya and Northern Mozambique) were more speciose than subtropical regions (southern Mozambique and Madagascar) but not significantly more diverse (Shannon H′). Although latitude was not a major influence on sponge community patterns, hard substratum assemblages did form a cline from the tropics to Southern Mozambique, linked by Madagascar. Substratum nature (habitat) was most important in influencing the suite and number of species present. Sponge assemblages of soft substrata were much more dissimilar, both within and between habitats, than those on hard substrata. There was a predictable variability in species richness between hard substratum habitats: coral reefs being speciose and caves being less so. Our findings showed that both patterns and influences on species richness may be decoupled from those influencing diversity. In our data species richness, but not diversity, showed striking regional and bathymetric trends. In addition, sponge species richness mainly split at coral reef vs. non‐reef habitats, whilst diversity divided principally into assemblages on hard and soft substrata. We consider this dichotomy of findings between species richness and diversity values to be important, as these are two principal measures used for the interpretation of biodiversity.     

An Ethnoarchaeological Study of Mobility, Architectural Investment, and Food Sharing among Madagascar's Mikea

Ethnoarchaeology is a field of study that aims to provide the information needed to draw reliable behavioral inferences from archaeological data. In this study, data from four settlement types (permanent villages, forest hamlets, seasonal hamlets, and foraging camps) of a forager–farmer population in southwestern Madagascar are examined from an archaeological perspective. Doing so shows that house size, house post diameter variability, outdoor workspace, trash disposal, and feature diversity jointly sort out settlements of different lengths of occupation. However, the relationship between mobility and material culture is not simply a product of the length of stay; it is also affected by differences in the social environments of settlements of different occupational lengths. Using the behavioral ecology of food sharing, we show that certain architectural changes that ensure privacy are expected to occur as settlements become larger and more permanent. These observations from Madagascar should be applicable to other areas.