The karyotypes of Dugesia species from Spain (Turbellaria,Tricladida)

Some species of Planarians, new to Spain, are recorded. Dugesia polychroa, D. sicula, D. iberica and D. gonocephala s. 1. have been investigated karyologically. The former possesses a diploid complement characteristic of the biotype A (2n = 8); the second is diploid with 2n = 18; diploidy and triploidy were found in sexual populations of D. iberica with n = 8. Triploidy occurred in all the asexual strains of the D. gonocephala group with a basic number of either 8 or 9. In this latter case B-chromosomes were occasionally found.     

Coalescent analyses support multiple mainland-to-island dispersals in the evolution of Malagasy Triaenops bats (Chiroptera: Hipposideridae)

Aim We investigate the directionality of mainland‐to‐island dispersals, focusing on a case study of an African‐Malagasy bat genus, Triaenops (Hipposideridae). Taxa include T. persicus from east Africa and three Triaenops species from Madagascar (T. auritus, T. furculus, and T. rufus). The evolution of this bat family considerably post‐dated the tectonic division of Madagascar from Africa, excluding vicariance as a viable hypothesis. Therefore, we consider three biogeographical scenarios to explain these species' current ranges: (A) a single dispersal from Africa to Madagascar with subsequent speciation of the Malagasy species; (B) multiple, unidirectional dispersals from Africa to Madagascar resulting in multiple, independent Malagasy lineages; or (C) early dispersal of a proto‐species from Africa to Madagascar, with later back‐dispersal of a descendant Malagasy taxon to Africa. Location East Africa, Madagascar, and the Mozambique Channel. Methods We compare the utility of phylogenetic and coalescent methodologies to address the question of directionality in a mainland‐to‐island dispersal event for recently diverged taxa. We also emphasize the application of biologically explicit demographic systems, such as the non‐equilibrium isolation‐with‐migration model. Here, these methods are applied to a four‐species haploid genetic data set, with simulation analyses being applied to validate this approach. Results Coalescent simulations favour scenario B: multiple, unidirectional dispersals from Africa to Madagascar resulting in multiple, independent Malagasy bat lineages. From coalescent dating, we estimate that the genus Triaenops was still a single taxon approximately 2.25 Ma. The most recent Africa to Madagascar dispersal occurred much more recently (c. 660 ka), and led to the formation of the extant Malagasy species, T. rufus. Main conclusions Haploid genetic data from four species of Triaenops are statistically most consistent with multiple, unidirectional dispersals from mainland Africa to Madagascar during the late Pleistocene.     

Historical biogeography of the coffee family (Rubiaceae,Gentianales) in Madagascar: case studies from the tribes Knoxieae,Naucleeae, Paederieae and Vanguerieae

Aim In Madagascar the family Rubiaceae includes an estimated 650 species representing 95 genera. As many as 98% of the species and 30% of the genera are endemic. Several factors make the Rubiaceae a model system for developing an understanding of the origins of the Malagasy flora. Ancestral area distributions are explicitly reconstructed for four tribes (Knoxieae, Naucleeae, Paederieae and Vanguerieae) with the aim of understanding how many times, and from where, these groups have originated in Madagascar. Location Indian Ocean Basin, with a focus on Madagascar. Methods Bayesian phylogenetic analyses are conducted on the four tribes. The results are used for reconstructing ancestral areas using dispersal–vicariance analyses. Phylogenetic uncertainties in the reconstructions are accounted for by conducting all analyses on the posterior distribution from the analyses. Results Altogether, 11 arrivals in Madagascar (one in Paederieae, five in Knoxieae, three in Vanguerieae, and two in Naucleeae) are reconstructed. The most common pattern is a dispersal event (followed by vicariance) from Eastern Tropical Africa. The Naucleeae and Paederieae in Madagascar differ and originate from Asia. Numerous out‐of‐Madagascar dispersals, mainly in the dioecious Vanguerieae, are reconstructed. Main conclusions The four tribes arrived several times in Madagascar via dispersal events from Eastern Tropical Africa, Southern Africa and Tropical Asia. The presence of monophyletic groups that include a number of species only found in Madagascar indicates that much endemism in the tribes results from speciation events occurring well after their arrival in Madagascar. Madagascar is the source of origin for almost all Rubiaceae found on the neighbouring islands of the Comoros, Mascarenes and Seychelles.     

Distribution and biogeography of the Paradiaptominae (Copepoda: Calanoida: Diaptomidae)

The Paradiaptominae, a subfamily of the large Diaptomidae family, is a small group of freshwater calanoids of which 24 species in four genera have been described. They are endemic to Africa with the exception of four species, Metadiaptomus asiaticus (Asia and Mongolia), M. gauthieri (Africa and Madagascar), Paradiaptomus greeni (India and Sri Lanka) and Neolovenula alluaudi (Canary Islands, North Africa, Baltic and Mediterranean countries). The North African species Metadiaptomus chevreuxi extends its range into Iraq and Iran. The Paradiaptominae are widely distributed in semi-permanent water bodies in the drier areas of Africa although most individual species have a restricted distribution. Only a few species have the ability to colonise permanent waters and these species are usually located at higher altitudes. The Paradiaptominae have not been recorded from the wet equatorial lowland areas of Africa. It seems likely that they are Gondwanian in origin as evidenced by their distribution (Africa, Madagascar, India and Sri Lanka). Neolovenula alluaudi (Mediterranean) shares morphological characters tenuously linked to the other species in the group and may either have a different origin or have branched off at an early stage in evolution of the group.     

The antiquity of Madagascar’s grasslands and the rise of C4 grassy biomes

Aim Grasslands and savannas, which make up > 75% of Madagascar’s land area, have long been viewed as anthropogenically derived after people settled on the island c. 2 ka. We investigated this hypothesis and an alternative – that the grasslands are an insular example of the post‐Miocene spread of C₄ grassy biomes world‐wide. Location Madagascar, southern Africa, East Africa. Methods We compared the number of C₄ grass genera in Madagascar with that in southern and south‐central African floras. If the grasslands are recent we would expect to find fewer species and genera in Madagascar relative to Africa and for these species and genera to have very wide distribution ranges in Madagascar. Secondly, we searched Madagascan floras for the presence of endemic plant species or genera restricted to grasslands. We also searched for evidence of a grassland specialist fauna with species endemic to Madagascar. Plant and animal species endemic to C₄ grassy biomes would not be expected if these are of recent origin. Results Madagascar has c. 88 C₄ grass genera, including six endemic genera. Excluding African genera with only one or two species, Madagascar has 86.6% of southern Africa’s and 89.4% of south‐central Africa’s grass genera. C₄ grass species make up c. 4% of the flora of both Madagascar and southern Africa and species : genus ratios are similar (4.3 and 5.1, respectively). Turnover of grasses along geographical gradients follows similar patterns to those in South Africa, with Andropogoneae dominating in mesic biomes and Chlorideae in semi‐arid grassy biomes. At least 16 monocot genera have grassland members, many of which are endemic to Madagascar. Woody species in frequently burnt savannas include both Madagascan endemics and African species. A different woody flora, mostly endemic, occurs in less frequently burnt grasslands in the central highlands, filling a similar successional niche to montane C₄ grasslands in Africa. Diverse vertebrate and invertebrate lineages have grassland specialists, including many endemic to Madagascar (e.g. termites, ants, lizards, snakes, birds and mammals). Grassland use of the extinct fauna is poorly known but carbon isotope analysis indicates that a hippo, two giant tortoises and one extinct lemur ate C₄ or CAM (crassulacean acid metabolism) plants. Main conclusions The diversity of C₄ grass lineages in Madagascar relative to that in Africa, and the presence of plant and animal species endemic to Madagascan grassy biomes, does not fit the view that these grasslands are anthropogenically derived. We suggest that grasslands invaded Madagascar after the late Miocene, part of the world‐wide expansion of C₄ grassy biomes. Madagascar provides an interesting test case for biogeographical analysis of how these novel biomes assembled, and the sources of the flora and fauna that now occupy them. A necessary part of such an analysis would be to establish the pre‐settlement extent of the C₄ grassy biomes. Carbon isotope analysis of soil organic matter would be a feasible method for doing this.     

The genus Opisthacanthus Peters, 1861 (Scorpiones: Hormuridae), a remarkable Gondwanian group of scorpions

New comments are proposed on the geographic distribution of genus Opisthacanthus, and the Gondwanian model is further supported. The diversity of the genus is extraordinary in Madagascar, with the same number of species as in continental Africa, but sub-Saharan Africa is home to six out of the nine groups currently recognized of Opisthacanthus. Given the affinities of the Opisthacanthus groups and their current distribution, a center of origin in Africa could be favored for these ancient scorpions. The proposed Gondwana model suggests that the Madagascar Opisthacanthus are closer to those of the New World, which is consistent with the affinities observed in morphological characters. A new species, Opisthacanthus titanus sp. n., is described from the Torotorofotsy Forest, located in Eastern Madagascar. The new species shows affinities with both Opisthacanthus madagascariensis Kraepelin, 1894 known from dry regions in the western portion of the island and Opisthacanthus lavasoa Lourenço, Wilmé & Waeber, 2016 only known from the extreme southeast of the island. The new species and O. madagascariensis have similar external morphologies but the morphometric values are markedly distinct. Moreover, O. madagascariensis is exclusively found in spiny forest thickets and open woodlands, whereas the new species was found in the humid forest of Torotorofotsy. The total number of species in Madagascar is now raised to twelve. Biogeographical scenarios are also proposed to infer the origin of the Opisthacanthus and better understand its distribution in the New World, in Africa and Madagascar.     

The genus Dugesia in Australia, with its phylogenetic analysis and historical biogeography (Platyhelminthes, Tricladida, Dugesiidae)

The new species Dugesia notogaea Sluys & Kawakatsu, sp. n. is described from Queensland, Australia, representing the first record of the genus Dugesia for that continent. A phylogenetic analysis of the 68 species of Dugesia resulted in the discovery of a new apomorphy for the genus, and a cladogram showing two major phyletic groups. The distributional range of one group has a western accent, whereas that of the other group has an eastern emphasis; the ranges of these two groups overlap in Africa and the Mediterranean region. We attempt to determine the ancestral area for both the Dugesiidae and Dugesia. A scenario for the historical biogeography of the genus Dugesia is discussed. In this scenario it is presumed that the geological history of the Australasian region enabled Dugesia's from southeast Asia to colonize northern Australia. © 1998 The Norwegian Academy of Science and Letters     

Wings or winds: inferring bat migration in a stepping-stone archipelago

Eocene ocean currents and prevailing winds correlate with over-water dispersals of terrestrial mammals from Africa to Madagascar. Since the Early Miocene (about 23 Ma), these currents flowed in the reverse direction, from the Indian Ocean towards Africa. The Comoro Islands are equidistant between Africa and Madagascar and support an endemic land vertebrate fauna that shares recent ancestry predominantly with Madagascar. We examined whether gene flow in two Miniopterus bat species endemic to the Comoros and Madagascar correlates with the direction of current winds, using uni- and bi-parentally inherited markers with different evolutionary rates. Coalescence-based analyses of mitochondrial matrilines support a Pleistocene (approximately 180,000 years ago) colonization event from Madagascar west to the Comoros (distance: 300 km) in the predicted direction. However, nuclear microsatellites show that more recent gene flow is restricted to a few individuals flying against the wind, from Grande Comore to Anjouan (distance: 80 km).     

New synonym of Drosophila yakuba Burla, 1954 (Diptera: Drosophilidae)

New biological and bibliographic information confirms that the widely accepted name Drosophila yakuba Burla, 1954 and the unused name Drosophila opisthomelaina are synonymous. The latter was coined by Nolte & Stoch in a 1950 work containing a disclaimer and is unavailable by strict application of Article 8b of the International Code of Zoological Nomenclature (3rd edn, 1985). In a previously overlooked publication, Nolte (1958) cites D.opisthomelaina as a senior synonym; the work also contains diagnostic information. Synonymy is not disputed but before 1958 the name was unavailable. Thus D. opisthomelaina Nolte, 1958 is treated as a junior rather than a senior synonym of D.yakuba. These nomenclatural corrections remove confusion concerning records of this species in southern Africa and will probably be met with general approval. The distribution in southern Africa and Madagascar of D.yakuba and closely related species: D.melanogaster Meigen, 1830, D.simulans Sturtevant, 1919 and D.teissieri Tsacas, 1971, are summarized.     

The compounds in Aloë leaf exudates: a review

The drug Bitter Aloes has been used for several thousands of years because of its purgative properties and later several species of the plant have been cultivated for horticultural interest. In addition, many more local therapeutic properties have been recorded. Research has been largely directed towards the physiologically active components during the 50s and 60s. Extensions to this work in the last decade have been made in Germany, Japan and South Africa. Compounds have been characterized from the dried exudate prepared for drug purposes and from a few species. A number of anthraquinones have been recognized both in the free state and as glycosides. Other compounds with phenolic groups include chromones and a phenyl-pyranone. Chromatographic methods have been developed for recognizing some of these compounds and estimating the levels of those of pharmacological interest. Distribution of some of the compounds among a number of species is described showing that among some groups it has taxonomic significance. The biology of secretion and exudation from Aloë leaves remains largely unknown although fragmentary evidence points to interesting and potentially useful activity in some of the components.     

A new citrus-feeding psyllid from the Comoro Islands, with a review of the Diaphorina amoena species group (Homoptera)

ABSTRACT. Analysis of host plant data for the seventy-one species of Diaphorina shows the genus to be unusually polyphagous, the species developing on eighteen families of dicotyledonous angiosperms. Apart from the common Asian citrus pest, Diaphorina citri , a second citrus-feeding species is described and discussed. This species belongs to the amoena species-group which is defined and a key to nine of the ten included species is given. Seven new species are described: flavipennis sp.n. and nigripennis sp.n. from East Africa on Strychnos usambarensis; huila sp.n. from Angola on Ptaeroxylon obliquum; turned sp.n., from South Africa (host unknown); orantimina sp.n. from Madagascar (host unknown); auberti sp.n. from Comoro Islands on citrus trees; and bispinulata sp.n. from Madagascar (host unknown).     

Revision of the genus Psix Kozlov & Lê (Hymenoptera: Scelionidae)

The genus Psix Kozlov & Lê (Hymenoptera: Scelionidae) is revised from a worldwide perspective. Twelve species are described as new: annulatus [Cameroon], asper [Uganda], aulax [Australia], confluus [Sri Lanka], flavicoxa [Ivory Coast, Zimbabwe], fusm [Australia], lacunatus [Pakistan east to Taiwan, south to Australia], metopa [Australia], rasilis [Ivory Coast, Gambia], sulcifer [Malaysia], viriosus [India east to Philippine Is.] and watshami [E. Africa, Madagascar] . Psix abnormis Kozlov & Lê [W. Africa east to at least India], glabris-crobus (Girault) nxomb. [Australia], olympus (Dodd) n.comb. [Australia], saccharicola (Mani) n.comb. [India], striaticeps (Dodd) n.comb. [W. Africa east to India, Madagascar] and tunetanus (Mineo and Szabó) n.comb. [Tunisia, Gambia, Ivory Coast, Saudi Arabia, S.W. Nearctic, Venezuela] are redescribed. An identification key for the species of Psix is presented. The relationships among species are discussed. The earliest derived species are generally found in Australia and southeast Asia. The more apomorphic species occur generally in Africa, southwest Asia and India. The distribution of Psix tunetanus has possibly been influenced by man. Details of the relationship with Trissolcus and Archi-phanurus are unclear; the position of Psix within the subfamily is therefore also obscure.     

Relationships of the MadagascarBignoniaceae: A striking case of convergent evolution

Most MadagascarBignoniaceae have indehiscent fruits and have been assigned to the tribeCrescentieae. As thus constituted, theCrescentieae are remarkably disjunct between Central America (and the West Indies) and Madagascar with a single monotypic genus also on continental Africa. This paper analyzes the evolutionary relationships of the MadagascarCrescentieae and concludes that they are descended from a different ancestral stock than the New WorldCrescentieae. A revised tribal taxonomy is proposed to reflect phylogenetic relationships withCrescentieae restricted to the neotropic species andColeeae resurrected for the indehiscent-fruited Madagascar species.     

Molecular phylogeny and generic‐level taxonomy of the widespread palaeotropical ‘Heteropsis clade’ (Nymphalidae: Satyrinae: Mycalesina)

The mycalesine butterfly genus Heteropsis Westwood, 1850 (Satyrinae: Mycalesina) has recently been conceived to be represented in three major palaeotropical regions (Madagascar, Africa and Asia), but there has been no formal taxonomic treatment covering this entire group. Studies aimed at understanding the evolutionary success of Mycalesina in the Old World tropics have been hampered by the lack of both a robust phylogeny and a stable nomenclature for this satyrine subtribe. Here, we present a well‐supported molecular phylogeny based on 10 genes and 133 exemplar taxa, representing almost all known species groups of Heteropsis (s.l.), and including all but four known species in Madagascar. We also combine sequences of the exemplars with a morphological matrix of 428 characters. The widespread ‘Heteropsis clade’ is confirmed as monophyletic, but lineages in different geographic regions also form endemic and well‐supported clades with deep divergences among them. Here we establish this group as comprising three genera, Heteropsis (Malagasy region only), Telinga Moore, 1880 (Asia), and Brakefieldia gen.n. (Africa). We recover the genera Telinga and Brakefieldia as sisters with high support. Each genus is taxonomically characterized and a revised synonymic checklist is appended with new combinations and some changes in rank. With a well‐resolved topology and updates to the taxonomy of the group, researchers are now in a position to explore the drivers of the spectacular radiation of the group, notably in Madagascar, where the highest phenotypic and species diversity occurs. This published work has been registered in ZooBank, http://zoobank.org/urn:lsid:zoobank.org:pub:AAF9F440‐A2D6‐4483‐BF35‐9BC074D9D29B .     

The biogeography of Miniopterus bats (Chiroptera: Miniopteridae) from the Comoro Archipelago inferred from mitochondrial DNA

The endemic fauna of the Comoro Archipelago is composed of a mixture of taxa originating from Africa and Madagascar. Bats are the only native land dwelling mammals on this archipelago, but the biogeographical origins for the vast majority of species within this group are ambiguous. We report here genetic analyses based on two mitochondrial DNA markers to infer the origin of Comorian bats belonging to a reputed species complex of Miniopterus that is further distributed across Africa and Madagascar. Phylogenetic reconstructions show that east African M. minor are not closely related to the insular Miniopterus of Madagascar and the Comoros (Grande Comore and Anjouan). The latter cluster into two distinct, monophyletic clades (Clade 1 and Clade 2). Representatives of these clades occur sympatrically both on the Comoros and on Madagascar, and are distinguished by a large genetic distance (K2P: 9.9% for cytochrome b). No haplotypes are shared between any islands, suggesting the absence of contemporary gene flow. Populations of the widespread Clade 1 are furthermore characterized by a significant inter‐island structure (Φ_CT = 0.249), and by high haplotype and nucleotide diversities (h = 0.90–0.98, π = 0.04–0.06). Demographic analyses of Clade 1 suggest secondary contact between two distinct phylogroups (Subclade 1 A and 1B) that reached Grande Comore and Anjouan, and a large, stable population with a long evolutionary history on Madagascar. These results and the current distribution of related lineages suggest that the Comoros were colonized independently at least two or three times by ancestors from Madagascar.     

Deep phylogenetic divergence between Scolytoplatypus and Remansus,a new genus of Scolytoplatypodini from Madagascar (Coleoptera,Curculionidae, Scolytinae)

Scolytoplatypodini Blandford is a monotypic tribe of ambrosia beetles found in Asia, Madagascar and Africa. Only three species are currently known from Madagascar and four additional species are here described as new to science. Phylogenetic analyses of morphological and molecular data revealed that four of the seven endemic species are deeply separated from all other species by genetic and distinct morphological characters and therefore placed in a new genus Remansus Jordal. The split between this ancient lineage and Scolytoplatypus Schaufuss was estimated to approximate Palaeocene age (63 Ma), extending the minimum age of ambrosia feeding for this tribe to the beginning of the Palaeocene‒Eocene thermal maximum (PETM). In addition to the ancient origin of Remansus in Madagascar during the Palaeocene, a second origin occurred in Scolytoplatypus no more than 13 Ma. A geographical origin of the latter in South-Eastern Africa was unequivocally inferred from the phylogenies.     

Phylogeography of the introduced species Rattus rattus in the western Indian Ocean,with special emphasis on the colonization history of Madagascar

Aim To describe the phylogeographic patterns of the black rat, Rattus rattus, from islands in the western Indian Ocean where the species has been introduced (Madagascar and the neighbouring islands of Réunion, Mayotte and Grande Comore), in comparison with the postulated source area (India). Location Western Indian Ocean: India, Arabian Peninsula, East Africa and the islands of Madagascar, Réunion, Grande Comore and Mayotte. Methods Mitochondrial DNA (cytochrome b, tRNA and D‐loop, 1762 bp) was sequenced for 71 individuals from 11 countries in the western Indian Ocean. A partial D‐loop (419 bp) was also sequenced for eight populations from Madagascar (97 individuals), which were analysed in addition to six previously published populations from southern Madagascar. Results Haplotypes from India and the Arabian Peninsula occupied a basal position in the phylogenetic tree, whereas those from islands were distributed in different monophyletic clusters: Madagascar grouped with Mayotte, while Réunion and Grand Comore were present in two other separate groups. The only exception was one individual from Madagascar (out of 190) carrying a haplotype that clustered with those from Réunion and South Africa. ‘Isolation with migration’ simulations favoured a model with no recurrent migration between Oman and Madagascar. Mismatch distribution analyses dated the expansion of Malagasy populations on a time‐scale compatible with human colonization history. Higher haplotype diversity and older expansion times were found on the east coast of Madagascar compared with the central highlands. Main conclusions Phylogeographic patterns supported the hypothesis of human‐mediated colonization of R. rattus from source populations in either the native area (India) or anciently colonized regions (the Arabian Peninsula) to islands of the western Indian Ocean. Despite their proximity, each island has a distinct colonization history. Independent colonization events may have occurred simultaneously in Madagascar and Grande Comore, whereas Mayotte would have been colonized from Madagascar. Réunion was colonized independently, presumably from Europe. Malagasy populations may have originated from a single successful colonization event, followed by rapid expansion, first in coastal zones and then in the central highlands. The congruence of the observed phylogeographic pattern with human colonization events and pathways supports the potential relevance of the black rat in tracing human history.     

Biogeography and diversification of hermit spiders on Indian Ocean islands (Nephilidae: Nephilengys)

The origin of the terrestrial biota of Madagascar and, especially, the smaller island chains of the western Indian Ocean is relatively poorly understood. Madagascar represents a mixture of Gondwanan vicariant lineages and more recent colonizers arriving via Cenozoic dispersal, mostly from Africa. Dispersal must explain the biota of the smaller islands such as the Comoros and the chain of Mascarene islands, but relatively few studies have pinpointed the source of colonizers, which may include mainland Africa, Asia, Australasia, and Madagascar. The pantropical hermit spiders (genus Nephilengys) seem to have colonized the Indian Ocean island arc stretching from Comoros through Madagascar and onto Mascarenes, and thus offer one opportunity to reveal biogeographical patterns in the Indian Ocean. We test alternative hypotheses on the colonization route of Nephilengys spiders in the Indian Ocean and simultaneously test the current taxonomical hypothesis using genetic and morphological data. We used mitochondrial (COI) and nuclear (ITS2) markers to examine Nephilengys phylogenetic structure with samples from Africa, southeast Asia, and the Indian Ocean islands of Madagascar, Mayotte, Réunion and Mauritius. We used Bayesian and parsimony methods to reconstruct phylogenies and haplotype networks, and calculated genetic distances and fixation indices. Our results suggest an African origin of Madagascar Nephilengys via Cenozoic dispersal, and subsequent colonization of the Mascarene islands from Madagascar. We find strong evidence of gene flow across Madagascar and through the neighboring islands north of it, while phylogenetic trees, haplotype networks, and fixation indices all reveal genetically isolated and divergent lineages on Mauritius and Réunion, consistent with female color morphs. These results, and the discovery of the first males from Réunion and Mauritius, in turn falsify the existing taxonomic hypothesis of a single widespread species, Nephilengys borbonica, throughout the archipelago. Instead, we diagnose three Nephilengys species: Nephilengys livida (Vinson, 1863) from Madagascar and Comoros, N. borbonica (Vinson, 1863) from Réunion, and Nephilengys dodo new species from Mauritius. Nephilengys followed a colonization route to Madagascar from Africa, and on through to the Mascarenes, where it speciated on isolated islands. The related golden orb-weaving spiders, genus Nephila, have followed the same colonization route, but Nephila shows shallower divergencies, implying recent colonization, or a moderate level of gene flow across the archipelago preventing speciation. Unlike their synanthropic congeners, N. borbonica and N. dodo are confined to pristine island forests and their discovery calls for evaluation of their conservation status.     

Phylogenetic relationships and biogeography of Ptilophora (Gelidiales,Rhodophyta) with descriptions of P. aureolusa,P. malagasya,and P. spongiophila from Madagascar

The genus Ptilophora currently includes 16 species occurring mostly in subtidal habitats of the Indo‐Pacific Ocean, but its global diversity and biogeography are poorly understood. We analyzed mitochondrial cox1, plastid rbcL and plastid psbA sequences from specimens collected in southern Madagascar during the 2010 Atimo Vatae expedition and studied their morphologies. Both morphological and molecular data sets demonstrated the presence of five species in southern Madagascar: Ptilophora hildebrandtii, P. pterocladioides, and three new species described here, P. aureolusa, P. malagasya, and P. spongiophila. Ptilophora aureolusa is distinguished by its compound pinnae with uniformly spaced pinnules. Ptilophora malagasya has an indistinct midrib and irregularly spaced pinnules. Ptilophora spongiophila, heavily coated with sponges, has cylindrical to flattened main axes, lateral and surface proliferations, and spatulate tetrasporangial sori. The species of Ptilophora found in Madagascar are endemic, except P. hildebrandtii, which also occurs in eastern Africa. Ptilophora comprises four phylogenetic groups that map to eastern Australia, Japan, western Australia/Southeast Asia/Madagascar/eastern Africa, and Madagascar/eastern Africa/Aegean Sea. Biogeographical analysis revealed that the ancestor of Ptilophora originated in Australia, but most of the species radiated from Madagascar.     

Migration, isolation and hybridization in island crop populations: the case of Madagascar rice

Understanding how crop species spread and are introduced to new areas provides insights into the nature of species range expansions. The domesticated species Oryza sativa or Asian rice is one of the key domesticated crop species in the world. The island of Madagascar off the coast of East Africa was one of the last major Old World areas of introduction of rice after the domestication of this crop species and before extensive historical global trade in this crop. Asian rice was introduced in Madagascar from India, the Malay Peninsula and Indonesia approximately 800-1400 years ago. Studies of domestication traits characteristic of the two independently domesticated Asian rice subspecies, indica and tropical japonica, suggest two major waves of migrations into Madagascar. A population genetic analysis of rice in Madagascar using sequence data from 53 gene fragments provided insights into the dynamics of island founder events during the expansion of a crop species' geographic range and introduction to novel agro-ecological environments. We observed a significant decrease in genetic diversity in rice from Madagascar when compared to those in Asia, likely the result of a bottleneck on the island. We also found a high frequency of a unique indica type in Madagascar that shows clear population differentiation from most of the sampled Asian landraces, as well as differential exchange of alleles between Asia and Madagascar populations of the tropical japonica subspecies. Finally, despite partial reproductive isolation between japonica and indica, there was evidence of indica/japonica recombination resulting from their hybridization on the island.