Molecular Phylogenetics and Biogeography of the Caribbean-Centered <Emphasis Type="Italic">Croton</Emphasis> Subgenus <Emphasis Type="Italic">Moacroton</Emphasis> (Euphorbiaceae s.s.)

Initial molecular phylogenetic studies established the monophylly of the large genus Croton (Euphorbiaceae s.s.) and suggested that the group originated in the New World. A denser and more targeted sampling of Croton species points to a South American origin for the genus. The nuclear and chloroplast genomes indicate a different rooting for the phylogeny of Croton. Although we favor the rooting indicated by the chloroplast data our conclusions are also consistent with the topology inferred from the nuclear data. The satellite genera Cubacroton and Moacroton are embedded within Croton. These two genera are synonimized into Croton and a new subgenus, Croton subgenus Moacroton, is circumscribed to include them and their allied Croton species. Croton subgenus Moacroton is morphologically characterized by a primarily lepidote indumentum, bifid or simple styles, and pistillate flowers with sepals that are connate at the base. This newly circumscribed subgenus is found from North America to South America, and in contrast to the majority of Croton species most of its members are found in mesic habitats. The group is most diverse in the greater Caribbean basin. A molecular clock was calibrated to the phylogeny using the available Euphorbiaceae fossils. The timing and pattern of diversification of Croton is consistent with both the GAARlandia and Laurasian migration hypotheses. A single species, Croton poecilanthus from Puerto Rico, is placed incongruently by its nuclear and chloroplast genomes. The possibility of this species being of hybrid origin is discussed.      

Diversification of Lupinus (Leguminosae) in the western New World: derived evolution of perennial life history and colonization of montane habitats

Previous phylogenetic studies of Lupinus (Leguminosae) based on nuclear DNA have shown that the western New World taxa form a monophyletic group representing the majority of species in the genus, with evidence for high rates of recent diversification in South America following final uplift of the Andes 2–4 million years ago (Mya). For this study, three regions of rapidly evolving non-coding chloroplast DNA (trnL intron, trnS–trnG, and trnT–trnL) were examined to estimate the timing and rates of diversification in the western New World, and to infer ancestral states for geographic range, life history, and maximum elevation. The western New World species (5.0–9.3 Mya, 0.6–1.1 spp./My) comprise a basally branching assemblage of annual plants endemic to the lower elevations of western North America, from which two species-rich clades are recently derived: (i) the western North American perennials from the Rocky Mountains, Great Basin, and Pacific Slope (0.7–2.1 Mya, 2.0–5.9 spp./My) and (ii) the predominantly perennial species from the Andes Mountains of South America and highlands of Mexico (0.8–3.4 Mya, 1.4–5.7 spp./My). Bayesian posterior predictive tests for association between life history and maximum elevation demonstrate that perennials are positively correlated with higher elevations. These results are consistent with a series of one or more recent radiations in the western New World, and indicate that rapid diversification of Lupinus coincides with the derived evolution of perennial life history, colonization of montane habitats, and range expansion from North America to South America.     

High connectivity and migration potentiate the invasion of Limnoperna fortunei (Mollusca: Mytilidae) in South America

Even after almost 30 years of Limnoperna fortunei introduction into South America, it is still unclear how the source and propagules are connected. Here, we present genetic evidence of population connectivity and gene flow of L. fortunei propagules from Asia into South America, proposing the main invasion routes into South America. To achieve that we expanded the sampling effort to cover all occurrence points of L. fortunei in South America. We sequenced the mtDNA COI gene and genotyped eight microsatellite loci (ML), and we evaluated the genetic source of the recently introduced population in Sobradinho hydroelectric power plant reservoir in Northeast Brazil. Our results revealed that China is the main genetic source of propagules for the Sobradinho population. We also found COI haplotypes and ML genotypes unique to South American populations, demonstrating a bridgehead effect likely caused by local mutation, adaptation, and admixture patterns that are maintained by high levels of gene flow among them. However, two genetic barriers were also detected. We concluded that L. fortunei is a well-established invader and is still rapidly expanding in Brazil, and the Amazon hydrographic basin is under an alarming threat of invasion.

     

A Global Review of Causes of Morbidity and Mortality in Free-Living Vultures

Vulture species worldwide play a key role in ecosystems as obligate scavengers, and several populations have had precipitous declines. Research on vulture health is critical to conservation efforts including free-living vultures and captive breeding programs, but is limited to date. In this systematic review, we determined the reported causes of free-living vulture species morbidity and mortality worldwide. The most commonly reported cause of mortality was from toxins (60%), especially lead and pesticides, followed by traumatic injury (49%), including collisions with urban infrastructure and gunshot. Neglected areas of research in free-living vulture health include infectious diseases (16%), endocrine and nutritional disorders (6%), and neoplasia (<?1%). Almost half of the studies included in the review were conducted in either Spain or the USA, with a paucity of studies conducted in South America and sub-Saharan Africa. The highest number of studies was on Griffon (Gyps fulvus) (24%) and Egyptian vultures (Neophron percnopterus) (19%), while half of all vulture species had five or fewer studies. Future investigations on free-living vulture health should focus on neglected areas of research, such as infectious diseases, and areas with gaps in the current literature, such as South America, sub-Saharan Africa, and under-studied vulture species.

     

Molecular phylogeny and phylogeography ofLupinus (Leguminosae) inferred from nucleotide sequences of therbcL gene and ITS 1 + 2 regions of rDNA

Total DNA was extracted from 55 species of theLeguminosae (including 29 species ofLupinus). The chloroplast generbcL and the ITS 1 + 2 regions of nuclear RNA genes were amplified by polymerase chain reaction (PCR) and sequenced directly. The sequences obtained were evaluated with character state (Maximum Parsimony) and distance methods (Neighbour Joining). Phylogenetic trees obtained with both data sets and methods are mostly congruent.Genisteae andCrotalarieae are sister groups and share ancestry with theThermopsideae/Podalyrieae. The genusLupinus, which forms a monophyletic clade within theGenisteae, shows a distinct Old-New World disjunction and appears to be divided into several more or less distinct groups: (1) The species from the eastern part of South America. (2) The homogeneous rough-seeded group (Scabrispermae) of the Old World species which is well distinguished from the smooth-seeded group (Malacospermae). (3) Within the rather heterogeneous smooth-seeded lupins a smaller subgroup withL. angustifolius, L. hispanicus andL. luteus is recognized. (4) Also separated are North American lupins and South American species with a western distribution. Genetic distances imply that the genusLupinus evolved during the last 12–14 million years, ruling out the hypothesis that the present Old-New World disjunction can be interpreted as a result of the continental drift. The genetic data suggest an origin in the Old World and an independant colonisation of the Eastern parts of South America as opposed to North America and the Western parts of South America.     

Neutral and functionally important genes shed light on phylogeography and the history of high‐altitude colonization in a widespread New World duck

Phylogeographic studies often infer historical demographic processes underlying species distributions based on patterns of neutral genetic variation, but spatial variation in functionally important genes can provide additional insights about biogeographic history allowing for inferences about the potential role of adaptation in geographic range evolution. Integrating data from neutral markers and genes involved in oxygen (O₂)‐transport physiology, we test historical hypotheses about colonization and gene flow across low‐ and high‐altitude regions in the Ruddy Duck (Oxyura jamaicensis), a widely distributed species in the New World. Using multilocus analyses that for the first time include populations from the Colombian Andes, we also examined the hypothesis that Ruddy Duck populations from northern South America are of hybrid origin. We found that neutral and functional genes appear to have moved into the Colombian Andes from both North America and southern South America, and that high‐altitude Colombian populations do not exhibit evidence of adaptation to hypoxia in hemoglobin genes. Therefore, the biogeographic history of Ruddy Ducks is likely more complex than previously inferred. Our new data raise questions about the hypothesis that adaptation via natural selection to high‐altitude conditions through amino acid replacements in the hemoglobin protein allowed Ruddy Ducks to disperse south along the high Andes into southern South America. The existence of shared genetic variation with populations from both North America and southern South America as well as private alleles suggests that the Colombian population of Ruddy Ducks may be of old hybrid origin. This study illustrates the breadth of inferences one can make by combining data from nuclear and functionally important loci in phylogeography, and underscores the importance of complete range‐wide sampling to study species history in complex landscapes.     

中国新发现外来入侵害虫——南美番茄潜叶蛾(鳞翅目:麦蛾科)

2017年8月,在新疆维吾尔自治区伊犁哈萨克自治州露地鲜食番茄上发现一种鳞翅目害虫,以幼虫潜食叶肉、蛀食果实,经鉴定为南美番茄潜叶蛾。该害虫原产南美洲的秘鲁,2006年入侵欧洲的西班牙,截至2017年5月,已在南美洲、欧洲、非洲、中美洲和亚洲的80多个国家和地区发生,严重危害鲜食番茄、加工番茄和樱桃番茄/圣女果,产量损失最高可达80%～100%。本文提供了南美番茄潜叶蛾的危害情况及主要形态鉴定特征,提出了防范其进一步扩散危害的措施建议以及今后应开展的主要研究方向,包括植物检疫、发生分布调查、生物学生态学特性研究、天敌资源挖掘利用等,以为积极应对南美番茄潜叶蛾对我国农业生产安全的威胁提供参考。     

Phylogeny and biogeography of the hollies (Ilex L., Aquifoliaceae)

The holly genus, Ilex L., in the monogeneric Aquifoliaceae, is the largest woody dioecious genus (>664 spp.), with a near‐cosmopolitan distribution in mesic environments. We constructed a phylogeny based on two nuclear genes, representing 177 species spread across the geographical range, and dated using macrofossil records. The five main clades had a common ancestor in the early Eocene, much earlier than previously suggested. Ilex originated in subtropical Asia and extant clades colonized South America by 30 Ma, North America by 23 Ma, Australia by 8 Ma, Europe by 6 Ma, and Africa by 4 Ma. South and North America were colonized multiple times. Ilex also reached Hawaii (10 Ma) and other oceanic islands. Macrofossil and pollen records show the genus has tracked mesic climates through time and space, and had a wider distribution before late Miocene global cooling. Our phylogeny provides a framework for studies in comparative ecology and evolution.     

First confirmed case of pseudocopulation in terrestrial orchids of South America: Pollination of Geoblasta pennicillata (Orchidaceae) by Campsomeris bistrimacula (Hymenoptera, Scoliidae)

The attraction of male pollinating insects by sexual deception is known for several orchids from the Mediterranean, Australia, South Africa and South America. The sexual delusion may be so enticing in some species that it elicits males to attempt copulation with insect-like structures of the labellum. Pollination by such a pseudocopulation mechanism is reported here for the terrestrial orchid Geoblasta penicillata (Chloraeinae) from subtropical South America. Observations of the pollination process were carried out in two wild populations 560 km distant from each other. The only pollinators seen in both populations were male Campsomeris bistrimacula (Scoliidae) wasps. They attempted copulation with the insect-like labellum by directing the genitalia to its base whereby pollinia got attached to the dorsal surface of the metasoma. The present case of pseudocopulation, which is in South America the second known and the first recorded in wild populations, represents a striking parallel to the Australian Calochilus campestris also pollinated by male scoliid wasp of the genus Campsomeris.     

Mapping the observed and modelled intracontinental distribution of non-marine ostracods from South America

Ecological niche modelling (ENM) has been used to quantify the potential occurrence of species, by identifying the main environmental factors that determine the presence of species across geographical space. We provide a large-scale survey of the distribution of ostracod species in South America, by using the domains of 25 river basins. From 221 known ostracod species, we estimate the potential distribution of 61 species, using ENM. Ten clusters of potential distribution patterns were found. Clusters 8 and 9 grouped most of the species, which presented high similarity of niche between them. Heterocypris paningi Brehm, 1934 (group 1) obtained higher niche variability. The minimum temperatures of the coldest month and the mean elevation of the river basin were most important to predict the potential distribution of ostracods of most groups. South America has a complex pattern of elevation, which affects species distributions indirectly through changes in local factors. For instance, the Andes mountains might impose a barrier for ostracod distribution in the southern part of South America because of the low temperatures and precipitation. The ENM indicated that some regions and/or basins of South America might be susceptible to the entry of several ostracod species, presently absent, including non-native species.

     

Molecular phylogeny supports a Northern Hemisphere origin of Golovinomyces (Ascomycota: Erysiphales)

Golovinomyces is a strictly herb-parasitic genus in the Erysiphaceae. Host–parasite co-speciation was reported recently between the genus Golovinomyces and Asteraceae from molecular phylogenetic analyses. The Asteraceae originated in South America and latterly expanded their geographic distribution into the Northern Hemisphere. If the co-speciation between Golovinomyces and Asteraceae originated in South America, the geographic origin of Golovinomyces could be assumed to be South America. To address this question, Golovinomyces species from hosts of the tribe Mutisieae, an asteraceous tribe endemic to South America, were collected and the ITS and 28S rDNA regions sequenced. Results indicate that Oidium mutisiae and Golovinomyces leuceriae isolated from the Mutisieae do not belong at the base of the Golovinomyces tree. Instead, they are situated separately within two different clades of Golovinomyces isolates from the Northern Hemisphere. Therefore, the tribe Mutisieae is not the most early host of Golovinomyces. Present results suggest that Golovinomyces originated in the Northern Hemisphere, and not in South America. The new species Oidium reginae for the previous O. mutisiae on Mutisia decurrens is proposed.     

Is Drosera meristocaulis a pygmy sundew? Evidence of a long-distance dispersal between Western Australia and northern South America

Background and aims

South America and Oceania possess numerous floristic similarities, often confirmed by morphological and molecular data. The carnivorous Drosera meristocaulis (Droseraceae), endemic to the Neblina highlands of northern South America, was known to share morphological characters with the pygmy sundews of Drosera sect. Bryastrum, which are endemic to Australia and New Zealand. The inclusion of D. meristocaulis in a molecular phylogenetic analysis may clarify its systematic position and offer an opportunity to investigate character evolution in Droseraceae and phylogeographic patterns between South America and Oceania.

Methods Drosera meristocaulis

was included in a molecular phylogenetic analysis of Droseraceae, using nuclear internal transcribed spacer (ITS) and plastid rbcL and rps16 sequence data. Pollen of D. meristocaulis was studied using light microscopy and scanning electron microscopy techniques, and the karyotype was inferred from root tip meristem.

Key Results

The phylogenetic inferences (maximum parsimony, maximum likelihood and Bayesian approaches) substantiate with high statistical support the inclusion of sect. Meristocaulis and its single species, D. meristocaulis, within the Australian Drosera clade, sister to a group comprising species of sect. Bryastrum. A chromosome number of 2n = approx. 32–36 supports the phylogenetic position within the Australian clade. The undivided styles, conspicuous large setuous stipules, a cryptocotylar (hypogaeous) germination pattern and pollen tetrads with aperture of intermediate type 7–8 are key morphological traits shared between D. meristocaulis and pygmy sundews of sect. Bryastrum from Australia and New Zealand.

Conclusions

The multidisciplinary approach adopted in this study (using morphological, palynological, cytotaxonomic and molecular phylogenetic data) enabled us to elucidate the relationships of the thus far unplaced taxon D. meristocaulis. Long-distance dispersal between southwestern Oceania and northern South America is the most likely scenario to explain the phylogeographic pattern revealed.     

Erratum to: Phylogeny and biogeography of the genus Stevia (Asteraceae: Eupatorieae): an example of diversification in the Asteraceae in the new world

The genus Stevia comprises approximately 200 species, which are distributed in North and South America, and are representative of the species diversity of the Asteraceae in the New World. We reconstructed the phylogenetic relationships using sequences of ITS and cpDNA and estimated the divergence times of the major clade of this genus. Our results suggested that Stevia originated in Mexico 7.0–7.3 million years ago (Mya). Two large clades, one with shrub species and another with herb species, were separated at about 6.6 Mya. The phylogenetic reconstruction suggested that an ancestor of Stevia was a small shrub in temperate pine–oak forests and the evolutionary change from a shrub state to a herb state occurred only once. A Brazilian clade was nested in a Mexican herb clade, and its origin was estimated to be 5.2 Mya, suggesting that the migration from North America to South America occurred after the formation of the Isthmus of Panama. The species diversity in Mexico appears to reflect the habitat diversity within the temperate pine–oak forest zone. The presence of many conspecific diploid–polyploid clades in the phylogenetic tree reflects the high frequency of polyploidization among the perennial Stevia species.

     

Carnivore taphonomy in South America: a review of actualistic studies and their implications in the southern Neotropics

Abstract

Actualistic studies on mammalian carnivore taphonomy in southern South America are reviewed here, including pumas, small cats, foxes, and other, smaller carnivores. Patterns for different carnivore taxa and their variation are elicited. Also temporal and spatial variability is analysed, and comparisons are made to other carnivores and regions. While generally these Neotropical carnivores produce low damage intensity, stronger modifications and their implications are described as well. These patterns and their variation are put in context by taking into account the particular physical and biotic conditions in the southern Neotropics.     

North American Glyptodontines (Xenarthra, Mammalia) in the Upper Pleistocene of northern South America

The Glyptodontidae is one of the most conspicuous groups in the Pleistocene megafauna of the Americas. The Glyptodontinae were involved in the Great American Biotic Interchange (GABI) and their earliest records in North America are about 3.9 Ma, suggesting an earlier formation of the Panamanian landbridge. Taxonomically it is possible to recognize two Pleistocene genera of Glyptodontinae:Glyptodon (ca. 1.8 – 0.008 Ma), restricted to South America, andGlyptotherium (ca. 2.6 – 0.009 Ma), including records in both North and Central America. Here we present the first report of the genusGlyptotherium in South America, from the Late Pleistocene of several fossil localities in Falcón State, northwestern Venezuela. A comparative analysis of the material, represented by cranial and postcranial parts, including the dorsal carapace and caudal rings, suggests a close affinity withGlyptotherium cylindricum (Late Pleistocene of Central Mexico). This occurrence in the latest Pleistocene of the northernmost region of South America Supports the bidirectional faunal migration during the GABI and the repeated re-immigration from North America of South American clades, as has been reported in other members of the Cingulata (e.g., Pampatheriidae).      

Observation of brown-throated three-toed sloths: mating behaviour and the simultaneous nurturing of two young

Bradypus variegatus is a member of the Order Pilosa, Family Bradypodidae, and is distributed in many subtropical and tropical countries in South and Central America. However, studies on this species in the wild are relatively limited and many aspects of its reproductive behaviour are unknown or unclear. The current report presents new observations of the reproductive behaviour of B. variegatus in its natural environment. These include details of both a male–female copulation and the simultaneous nurturing of two young sloths.     

Nuclear ribosomal internal transcribed spacer 1 (ITS1) variation in the Anastrepha fraterculus cryptic species complex (Diptera,Tephritidae) of the Andean region

The nuclear ribosomal internal transcribed spacer 1 (ITS1) was sequenced for Anastrepha fraterculus (Wiedemann, 1830) originating from 85 collections from the northern and central Andean countries of South America including Argentina (Tucumán), Bolivia, Perú, Ecuador, Colombia, and Venezuela. The ITS1 regions of additional specimens (17 collections) from Central America (México, Guatemala, Costa Rica, and Panamá), Brazil, Caribbean Colombia, and coastal Venezuela were sequenced and together with published sequences (Paraguay) provided context for interpretation. A total of six ITS1 sequence variants were recognized in the Andean region comprising four groups. Type I predominates in the southernmost range of Anastrepha fraterculus. Type II predominates in its northernmost range. In the central and northern Andes, the geographic distributions overlap and interdigitate with a strong elevational effect. A discussion of relationships between observed ITS1 types and morphometric types is included.     

Identification of priority areas in South America for exploration of natural enemies for classical biological control of Tetranychus evansi (Acari: Tetranychidae) in Africa

The red spider mite Tetranychus evansi Baker and Pritchard is a pest of tomato in East and Southern Africa. It is probably native to South America. Three models were established to identify priority areas for the search of natural enemies in South America for classical biological control of this pest in Africa. The models were based on the concept of “fundamental ecological niche”, predicting regions in South America that have similar environmental conditions to areas where the mite is a problem in Africa, using Desktop-GARP (Genetic Algorithm for Rule-set Production). Based on the model established with data sets from Kenya and Zimbabwe, it was determined that priority areas include areas in Brazil, Argentina, Paraguay and Uruguay, as well as some restricted areas in other South American countries.     

Eccremidium (Ditrichaceae) new to South America

Abstract

The occurrence of Eccremidium, a rare pygmy moss, in Brazil, South America, is reported. Though it is conspecific with the recently described E. floridanum Crum the differences are highlighted for a better understanding of the variable nature of the species and its relationship with the Australian and South African E. exiguum.