Monotypic Lineage Research Articles

Evolutionary relationships, hybridization and diversification under domestication of the locoto chile (Capsicum pubescens) and its wild relatives.

Patterns of genetic variation in crops are the result of multiple processes that have occurred during their domestication and improvement, and are influenced by their wild progenitors that often remain understudied. The locoto chile, Capsicum pubescens, is a crop grown mainly in mid-highlands of South-Central America. This species is not known from the wild and exists only as a cultigen. The evolutionary affinities and exact origin of C. pubescens have still not been elucidated, with hypotheses suggesting its genetic relatedness and origin to two wild putative ancestral Capsicum species from the Central Andes, C.eximium and C. cardenasii. In the current study, RAD-sequencing was applied to obtain genome-wide data for 48 individuals of C. pubescens and its wild allies representing different geographical areas. Bayesian, Maximum Likelihood and coalescent-based analytical approaches were used to reconstruct population genetic patterns and phylogenetic relationships of the studied species. The results revealed that C. pubescens forms a well-defined monotypic lineage closely related to wild C. cardenasii and C. eximium, and also to C. eshbaughii. The primary lineages associated with the diversification under domestication of C. pubescens were also identified. Although direct ancestor-descendant relationship could not be inferred within this group of taxa, hybridization events were detected between C. pubescens and both C.cardenasii and C. eximium. Therefore, although hybrid origin of C. pubescens could not be inferred, gene flow involving its wild siblings was shown to be an important factor contributing to its contemporary genetic diversity. The data allowed for the inference of the center of origin of C. pubescens in central-western Bolivia highlands and for better understanding of the dynamics of its gene pool. The results of this study are essential for germplasm conservation and breeding purposes, and provide excellent basis for further research of the locoto chile and its wild relatives.

First report of Fusarium sporotrichioides causing Fusarium fruit rot on peaches in Pakistan.

Peach (Prunus persica) is an important stone fruit crop cultivated on 14,350 hectares in temperate areas of Pakistan, where post-harvest fungal rots cause major economic losses for growers. During April-August 2019, rotted peaches were observed in fruit markets of Rawalpindi district (33° 37' 33.8052'' N and 73° 4' 17.1912'' E), Punjab Province, Pakistan. Symptomatic fruit were surface sterilized for 3 min in 0.5% NaClO and 1 min in 70% ethanol, then rinsed three times in sterilized distilled water and air-dried for 30 minutes on filter paper. Tissue segments were excised from the margins of rot lesions and placed on potato dextrose agar (PDA), followed by incubation for one week at 25 +1o C. Furthermore, to maintain original sporodochial morphology and conidial description tissue segments were also grown on carnation leaf agar (CLA) and synthetic nutrient agar (SNA) (Sever et al., 2012). A total of 22 isolates were obtained from different fruit markets; colonies were fast-growing with pinkish-white, fluffy mycelia. Microconidia were abundant, 7.5 to 11.3 × 2.1 to 4.1 μm, oval to spindle-shaped, thin-walled, and hyaline whereas, macroconidia were thick-walled, sickle-shaped, 5- to 7-septate, hyaline, and 23.5 to 39.7 × 3.7 to 7.0 μm on carnation leaf agar. Virulence intensity of fungal isolates was confirmed after pathogenicity. Based on morphological characteristics, isolates were identified provisionally as Fusarium sporotrichioides (Leslie and Summerell 2006). For molecular identification, three target gene regions (ITS, elongation factor (EF), and β-tubulin benA) were amplified for highly pathogenic fungal isolates (FUS21K, FUS9SM, and FUS63KP) (O'Donnell et al. 2015). BLAST searches of the obtained sequences indicated 100% homology with GenBank accession number MN452643, and 99.56% homology with MT635298 for the ITS region, similarly 100% identity with GenBank accession numbers MN555016, MN555126, and MN555037 for the EF gene, and 100% homology with GenBank accession numbers MK435577, MH791363, and GQ915448 for β-tubulin benA of the F. sporotrichioides species complex (O'Donnell et al. 2015). Sequences were deposited in GenBank; accession numbers for each gene were as follows: ITS, ON180670, ON180671, and ON180672; EF, ON312093, ON312094, and ON312095; and β-tubulin benA, ON312090, ON312091, and ON312092. Maximum likelihood analysis on RPB1 and RPB2 nucleotide sequences of various fusaria was conducted which revealed that F. sporotrichioides formed a monophyletic relationship to terminal fusarium clade (TFC) comprising 22 strongly supported species complexes and 10 monotypic lineages, which were provisionally recognized as Fusarium. To complete Koch's postulates, 10μl aliquots of spore suspensions (106 spores/ml) of each FUS21K, FUS9SM and FUS63KP were pipetted individually onto six ripe, asymptomatic peaches. Sterile distilled water was applied as a negative control on four fruit. Fruit were incubated at 25 ± 1°C for one week in a sterile moist chamber, and the trial was conducted three times. Rot symptoms associated with pinkish-white fluffy mycelia were observed on inoculated fruits after 72 hours, whereas no mycelium was observed on the negative controls. The cultures on PDA, CLA and SNA from each of the inoculated fruit were morphologically identical to the original culture. The pathogen was confirmed as a member of F. sporotrichioides species complex based on pinkish-white mycelium, with red color on the underside of petri plates and the manner in which conidia are born on conidiophores. This is the first report of F. sporotrichioides on peaches from Pakistan, providing an important foundation for peach growers, agricultural advisers, plant pathologists, and plant breeders to improve the management of this economically damaging disease.

New Species of Large-Spored Alternaria in Section Porri Associated with Compositae Plants in China.

Alternaria is a ubiquitous fungal genus including saprobic, endophytic, and pathogenic species associated with a wide variety of substrates. It has been separated into 29 sections and seven monotypic lineages based on molecular and morphological data. Alternaria sect. Porri is the largest section, containing the majority of large-spored Alternaria species, most of which are important plant pathogens. Since 2015, of the investigations for large-spored Alternaria species in China, 13 species were found associated with Compositae plants based on morphological comparisons and phylogenetic analyses. There were eight known species and five new species (A. anhuiensis sp. nov., A. coreopsidis sp. nov., A. nanningensis sp. nov., A. neimengguensis sp. nov., and A. sulphureus sp. nov.) distributed in the four sections of Helianthiinficientes, Porri, Sonchi, and Teretispora, and one monotypic lineage (A. argyranthemi). The multi-locus sequence analyses encompassing the internal transcribed spacer region of rDNA (ITS), glyceraldehydes-3-phosphate dehydrogenase (GAPDH), Alternaria major allergen gene (Alt a 1), translation elongation factor 1-alpha (TEF1), and RNA polymerase second largest subunit (RPB2), revealed that the new species fell into sect. Porri. Morphologically, the new species were illustrated and compared with other relevant large-spored Alternaria species in the study. Furthermore, A. calendulae, A. leucanthemi, and A. tagetica were firstly detected in Brachyactis ciliate, Carthamus tinctorius, and Calendula officinalis in China, respectively.

Pulverulina, a New Genus of Agaricales for Clitocybe ulmicola

A new genus, Pulverulina, is described to accommodate the monotypic lineage Clitocybe ulmicola in the Porotheleaceae. Pulverulina ulmicola is characterized by small, clitocyboid, pileate-stipitate basidiomata with a tough, pruinose stipe; distant decurrent lamellae; smooth inamyloid basidiospores; long, abundant caulocystidia; interwoven lamellar trama, and lignicolous habit on bark of living trees. A taxonomic description and illustrations are provided together with molecular phylogenetic analysis of 14 genera of Porotheleaceae. One new taxon and 3 new combinations are proposed: Pulverulina gen. nov. and Pulverulina ulmicola comb. nov., Hydropus rugosodiscus comb. nov., and Leucoinocybe auricoma comb. nov.

<p><strong><em>Alternaria</em></strong><strong> <em>ershadii</em> <em>sp. nov</em>. a new species isolated from wheat black head mold in Iran</strong></p>

In the continuation of studies on Alternaria species from wheat plants with black head mold symptoms, 10 isolates with typical characteristics of the section Pseudoalternaria were isolated and studied by a combined approach based on morphological characteristics and phylogenetic analyses using sequence data sets of the internal transcribed spacer of ribosomal DNA (ITS-rDNA), glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and plasma membrane adenosine triphosphatase (ATPase) genes. These isolates represented a new and previously undescribed species in this section which is illustrated and described here as Alternaria ershadii sp. nov. Also based on our phylogenetic analyses, it was revealed that Alternaria brassicifolii, which was recently described from Brassica rapa subsp. pekinensis in Korea and placed in this section, formed a well separated monotypic lineage distinct from the other members in the section Pseudoalternaria. Comparisons of three-dimensional sporulation patterns and conidial characteristics supported the molecular results. So, at present, Alternaria section Pseudoalternaria contains only seven species viz. Alternaria altcampina, A. arrhenatheri, A. ershadii, A. inflata, A. kordkuyana, A. parvicaespitosa and A. rosae. Morphological comparisons of Alternaria ershadii with other species in the section Pseudoalternaria and with Alternaria brassicifolii is also provided.

New biogeographical makeup for colonisation of the Baja California Peninsula, with the description of a new Onthophagus (Coleoptera: Scarabaeidae: Scarabaeinae)

ABSTRACTThe dung beetles of the Onthophagus chevrolati species group are preponderantly associated to montane habitats and high plains in the Mexican Transition Zone. Herein, we describe O. bajacalifornianus new species, the first of this species group from the southern Baja California Peninsula, which inhabits xeric shrublands near the sea level from the sandy foothills of the Sierra de la Laguna. The new species corresponds to a new monotypic phyletic lineage among the American Onthophagus. The multiple biogeographical origins of the Baja Californian endemic biota are briefly discussed. The need for recognising two new biogeographical elements is highlighted: the Baja Californian Paleoamerican sub-pattern (Miocenic Holarctic affinities) and the Neotropical Baja Californian pattern (Miocenic Neotropical affinities).http://www.zoobank.org/urn:lsid:zoobank.org:pub:7840ECCA-4CCC-4DB1-A30D-560FEE84AABF

Discovery of a deeply divergent new lineage of vine snake (Colubridae: Ahaetuliinae: Proahaetulla gen. nov.) from the southern Western Ghats of Peninsular India with a revised key for Ahaetuliinae.

The Western Ghats are well known as a biodiversity hotspot, but the full extent of its snake diversity is yet to be uncovered. Here, we describe a new genus and species of vine snake Proahaetulla antiqua gen. et sp. nov., from the Agasthyamalai hills in the southern Western Ghats. It was found to be a member of the Ahaetuliinae clade, which currently comprises the arboreal snake genera Ahaetulla, Dryophiops, Dendrelaphis and Chrysopelea, distributed in South and Southeast Asia. Proahaetulla shows a sister relationship with all currently known taxa belonging to the genus Ahaetulla, and shares ancestry with Dryophiops. In addition to its phylogenetic position and significant genetic divergence, this new taxon is also different in morphology from members of Ahaetuliinae in a combination of characters, having 12–13 partially serrated keels on the dorsal scale rows, 20 maxillary teeth and 3 postocular scales. Divergence dating reveals that the new genus is ancient, dating back to the Mid-Oligocene, and is one of the oldest persisting monotypic lineages of snakes in the Western Ghats. This discovery adds to the growing list of ancient lineages endemic to the Agasthyamalai hills and underscores the biogeographic significance of this isolated massif in the southern Western Ghats.

Near-Complete Genome Assembly of Alternaria brassicae-A Necrotrophic Pathogen of Brassica Crops.

Alternaria brassicae, a necrotrophic fungal pathogen, causes Alternaria blight, an important disease of brassica crops. Although many Alternaria spp. have been sequenced, no genome information is available for A. brassicae, a monotypic lineage within the Alternaria genus. A highly contiguous genome assembly of A. brassicae has been generated using Nanopore MinION sequencing with an N50 of 2.98 Mb, yielding nine full chromosome-level sequences. This study adds to the current genomic resources available for the genus Alternaria and will provide opportunities for further analyses to unravel the mechanisms underlying pathogenicity of this important necrotrophic pathogen.

The Immature Stages, Biology, and Phylogenetic Relationships of Rotunda rotundapex (Lepidoptera: Bombycidae).

The life history, morphology, and biology of the immature stages and phylogenetic relationships of Rotunda rotundapex (Miyata & Kishida, 1990) are described and illustrated for the first time. The species is univoltine: eggs hatch in spring (March or April) and the life cycle from egg to adult is completed in about 3 wk, with larvae developing rapidly on young leaves of the host plants, Morus australis and to a lesser extent Broussonetia monoica (Moraceae), and adults emerging in April–May. Eggs are laid in clusters on twigs of the host plant, are covered by scales during female oviposition, and remain in diapause for the remainder of the year (i.e., for 10–11 mo). Larvae (all instars) are unique among the Bombycidae in that they lack a horn on abdominal segment 8. A strongly supported molecular phylogeny based on six genes (5.0 Kbp: COI, EF-1α, RpS5, CAD, GAPDH, and wgl) representing seven genera of Bombycinae from the Old World revealed that Rotunda is a distinct monotypic lineage sister to Bombyx. This phylogenetic position, together with morphological data of the immature stages (egg and larval chaetotaxy), supports the current systematic classification in which the species rotundapex has been placed in a separate genus (Rotunda) from Bombyx in which it was previously classified.

Uncovering the diversity of the neotropical genus Elaphopsocus (‘Psocoptera’: Psocidae: Amphigerontiinae): from one to ten species

For 75 years, the genus Elaphopsocus was considered a monotypic lineage of neotropical psocids. As a result of recent work in South America, this genus presently includes seven species from Brazil and Colombia. We here describe three new species from the East Colombian high Andes.

Fusarium agapanthi sp. nov., a novel bikaverin and fusarubin-producing leaf and stem spot pathogen of Agapanthus praecox (African lily) from Australia and Italy

This study was conducted to characterize a novel Fusarium species that caused leaf and stem spot on Agapanthus praecox (Agapanthus, African lily) in northern Italy and leaf rot and spot on the same host in Melbourne, Australia. Formally described as Fusarium agapanthi, this pathogen was analyzed using phenotypic, phytopathogenic, secondary metabolite, molecular phylogenetic and genomic data. Five strains were characterized, including one isolated in 1999 from symptomatic A. praecox in Saluzzo, Italy, and four in 2010 from diseased leaf tissue from the same host exhibiting leaf rot and spot symptoms in the Melbourne Gardens, Royal Botanic Gardens Victoria, Australia. Maximum parsimony and maximum likelihood molecular phylogenetic analyses of portions of six individual genes and the combined dataset all strongly supported F. agapanthi either as the earliest diverging genealogically exclusive lineage in the American Clade of the F. fujikuroi species complex, or alternatively a novel monotypic lineage sister to the American Clade. Koch’s postulates were completed on dwarf blue- and large white-flowering varieties of A. praecox, where two isolates of F. agapanthi produced slowly spreading necrotic lesions when inoculated onto leaves and flower stems. Fusarium agapanthi is distinguished from other fusaria by the production of densely branched aerial conidiophores with polyphialides throughout the aerial mycelium on synthetic nutrient-poor agar. BLASTn searches of the F. agapanthi NRRL 31653 and NRRL 54464 (= VPRI 41787) genome sequences were conducted to predict sexual reproductive mode and mycotoxin potential. Results indicated that they possessed MAT1-2 and MAT1-1 idiomorphs, respectively, indicating that this species might be heterothallic. Furthermore, based on the presence of homologs of the bikaverin and fusarubin biosynthetic gene clusters in the F. agapanthi genomes, liquid chromatography-mass spectrometry analysis was conducted and confirmed production of these secondary metabolites in rice and corn kernel cultures of the fungus.

Arktocara yakataga, a new fossil odontocete (Mammalia, Cetacea) from the Oligocene of Alaska and the antiquity of Platanistoidea.

The diversification of crown cetacean lineages (i.e., crown Odontoceti and crown Mysticeti) occurred throughout the Oligocene, but it remains an ongoing challenge to resolve the phylogenetic pattern of their origins, especially with respect to stem lineages. One extant monotypic lineage, Platanista gangetica (the Ganges and Indus river dolphin), is the sole surviving member of the broader group Platanistoidea, with many fossil relatives that range from Oligocene to Miocene in age. Curiously, the highly threatened Platanista is restricted today to freshwater river systems of South Asia, yet nearly all fossil platanistoids are known globally from marine rocks, suggesting a marine ancestry for this group. In recent years, studies on the phylogenetic relationships in Platanistoidea have reached a general consensus about the membership of different sub-clades and putative extinct groups, although the position of some platanistoid groups (e.g., Waipatiidae) has been contested. Here we describe a new genus and species of fossil platanistoid, Arktocara yakataga, gen. et sp. nov. from the Oligocene of Alaska, USA. The type and only known specimen was collected from the marine Poul Creek Formation, a unit known to include Oligocene strata, exposed in the Yakutat City and Borough of Southeast Alaska. In our phylogenetic analysis of stem and node-based Platanistoidea, Arktocara falls within the node-based sub-clade Allodelphinidae as the sister taxon to Allodelphis pratti. With a geochronologic age between ∼29–24 million years old, Arktocara is among the oldest crown Odontoceti, reinforcing the long-standing view that the diversification for crown lineages must have occurred no later than the early Oligocene.

From Clinging to Digging: The Postembryonic Skeletal Ontogeny of the Indian Purple Frog, Nasikabatrachus sahyadrensis (Anura: Nasikabatrachidae).

The Indian Purple frog, Nasikabatrachus sahyadrensis, occupies a basal phylogenetic position among neobatrachian anurans and has a very unusual life history. Tadpoles have a large ventral oral sucker, which they use to cling to rocks in torrents, whereas metamorphs possess adaptations for life underground. The developmental changes that underlie these shifts in habits and habitats, and especially the internal remodeling of the cranial and postcranial skeleton, are unknown. Using a nearly complete metamorphic series from free-living larva to metamorph, we describe the postembryonic skeletal ontogeny of this ancient and unique monotypic lineage. The torrent-dwelling larva possesses a dorsoventrally flattened body and a head with tiny dorsal eyes, robust lower and upper jaw cartilages, well-developed trabecular horns, and a definable gap between the trabecular horns and the tip of the snout. Unlike tadpoles of many other frogs, those of Nasikabatrachus retain larval mouthparts into late metamorphic stages. This unusual feature enables the larvae to maintain their clinging habit until near the end of metamorphosis. The subsequent ontogenetic shift from clinging to digging is correlated with rapid morphological changes and behavioral modifications. Metamorphs are equipped with a shortened tibiafibula and ossified prehallical elements, which likely facilitate initial digging using the hind limbs. Subsequently, the frogs may shift to headfirst burrowing by using the wedge-shaped skull, anteriorly positioned pectoral girdle, well-developed humeral crests and spatula-shaped forelimbs. The transition from an aquatic life in torrents to a terrestrial life underground entails dramatic changes in skeletal morphology and function that represent an extreme in metamorphic remodeling. Our analysis enhances the scope for detailed comparative studies across anurans, a group renowned for the diversity of its life history strategies.

Towards a natural classification of Astrosphaeriella-like species; introducing Astrosphaeriellaceae and Pseudoastrosphaeriellaceae fam. nov. and Astrosphaeriellopsis, gen. nov.

Astrosphaeriella sensu lato is a common genus occurring on bamboo, palms and stout grasses. Species of Astrosphaeriella have been collected from various countries in tropical, subtropical or temperate regions. In Asia, species have been collected in Brunei, China, Indonesia, Japan, Philippines and Vietnam. There have been several morphological studies on Astrosphaeriella, but molecular work and phylogenetic analyses are generally lacking. Taxa included in Astrosphaeriella were characterized in three main groups 1) typical Astrosphaeriella species (sensu stricto) having carbonaceous, erumpent, conical ascostromata 2) atypical Astrosphaeriella species (sensu lato) having immersed, coriaceous ascostromata with short to long papilla and 3) lophiostoma-like species having immersed ascostromata with slit-like openings. Some of the latter Astrosphaeriella species, having slit-like openings, have been transferred to Fissuroma and Rimora in Aigialaceae. In this study five type specimens of Astrosphaeriella were loaned from herbaria worldwide and re-examined and are re-described and illustrated. Collections of Astrosphaeriella were also made in Thailand and morphologically examined. Pure cultures were obtained from single spores and used in molecular studies. The asexual morph was induced on sterile bamboo pieces placed on water agar. Phylogenetic analyses of combined LSU, SSU and TEF1 sequence data of astrosphaeriella-like species using Bayesian, Maximum parsimony (MP) and Randomized Accelerated Maximum Likelihood (RAxML) analyses were carried out. Phylogenetic analyses show that species of Astrosphaeriella can be distinguished in at least three families. Species of Astrosphaeriella sensu stricto with erumpent, carbonaceous ascostromata, form a strongly supported clade with Pteridiospora species and a new family, Astrosphaeriellaceae, is introduced to accommodate these taxa. The genera are revised and Astrosphaeriella bambusae, A. neofusispora, A. neostellata, A. thailandica, A. thysanolaenae and Pteridiospora chiangraiensis are introduced as new species. Astrosphaeriella exorrhiza is reported on a dead stem of Thysanolaena maxima and is the first record for Thailand. Reference specimens for A. fusispora and A. tornata are designated to stabilize the taxonomy of Astrosphaeriella. The coelomycetous asexual morph of A. bambusae is reported and forms hyaline, globose to subglobose, aseptate conidia. Species of Astrosphaeriella sensu lato with immersed, coriaceous ascostromata, with short to long papilla and striate ascospores, form a sister clade with Tetraplosphaeriaceae. The genus Pseudoastrosphaeriella is introduced to accommodate some of these taxa with three new species and three new combinations, viz. P. aequatoriensis, P. africana, P. bambusae, P. longicolla, P. papillata and P. thailandensis. A new family Pseudoastrosphaeriellaceae is introduced to accommodate this presently monotypic lineage comprising Pseudoastrosphaeriella. The asexual morph of P. thailandensis is described. Astrosphaeriella bakeriana forms a distinct clade basal to Aigialaceae. Astrosphaeriella bakeriana is excluded from Astrosphaeriella and a new genus Astrosphaeriellopsis, placed in Dothideomycetes genera incertae sedis, is introduced to accommodate this taxon. Fissuroma aggregata (Aigialaceae) is re-visited and is shown to be a cryptic species. Three new species of Fissuroma and a new combination are introduced based on morphology and phylogeny viz. F. bambusae, F. fissuristoma, F. neoaggregata and F. thailandicum.

Communities of Cultivable Root Mycobionts of the Seagrass Posidonia oceanica in the Northwest Mediterranean Sea Are Dominated by a Hitherto Undescribed Pleosporalean Dark Septate Endophyte.

Seagrasses, a small group of submerged marine macrophytes, were reported to lack mycorrhizae, i.e., the root-fungus symbioses most terrestrial plants use for nutrient uptake. On the other hand, several authors detected fungal endophytes in seagrass leaves, shoots, rhizomes, and roots, and an anatomically and morphologically unique dark septate endophytic (DSE) association has been recently described in the roots of the Mediterranean seagrass Posidonia oceanica. Nevertheless, the global diversity of seagrass mycobionts is not well understood, and it remains unclear what fungus forms the DSE association in P. oceanica roots. We isolated and determined P. oceanica root mycobionts from 11 localities in the northwest Mediterranean Sea with documented presence of the DSE association and compared our results with recent literature. The mycobiont communities were low in diversity (only three species), were dominated by a single yet unreported marine fungal species (ca. 90 % of the total 177 isolates), and lacked common terrestrial and freshwater root mycobionts. Our phylogenetic analysis suggests that the dominating species represents a new monotypic lineage within the recently described Aigialaceae family (Pleosporales, Ascomycota), probably representing a new genus. Most of its examined colonies developed from intracellular microsclerotia occupying host hypodermis and resembling microsclerotia of terrestrial DSE fungi. Biological significance of this hitherto overlooked seagrass root mycobiont remains obscure, but its presence across the NW Mediterranean Sea and apparent root intracellular lifestyle indicate an intriguing symbiotic relationship with the dominant Mediterranean seagrass. Our microscopic observations suggest that it may form the DSE association recently described in P. oceanica roots.

Recovering the evolutionary history of Africa’s most diverse viper genus: morphological and molecular phylogeny of Bitis (Reptilia: Squamata: Viperidae)

Assessing evolutionary relationships among wide-ranging species can be particularly beneficial to our understanding of speciation patterns and biogeography of taxa, with broad implications for conservation and applications for human health. Integrative phylogenetic analyses that incorporate multiple independent datasets (e.g., DNA, protein, phenotype) can resolve many problematic issues in systematics such as cryptic diversity and incongruence between datasets. Vipers in the genus Bitis are widely distributed throughout much of sub-Saharan Africa, filling a variety of ecological niches and presenting an important public health problem. However, evolutionary relationships among this medically and ecologically important genus have not been fully resolved due to inadequate taxon sampling and lack of informative characters. Here, we conduct the first phylogenetic study incorporating complete sampling of known species within the genus Bitis. Using morphological, molecular, and combined approaches under multiple criteria, we recovered many of the species groups detected by previous investigators, further validating four currently recognized subgenera. Bitis arietans and Bitis worthingtoni appear to be early-diverging, monotypic lineages, while the “big Bitis” group and the small southern African species form distinct clades. Although our study provides additional information regarding the interspecific relationships within Bitis, the placement of Bitis albanica, Bitis heraldica, and Bitis inornata remains problematic. This study enhances our understanding of the evolutionary history of species within the genus Bitis incorporating a combined evidence approach to phylogenetics.

A new species of Paramunida Baba, 1988 from the Central Pacific Ocean and a new genus to accommodate P. granulata (Henderson, 1885).

The genus Paramunida belongs to the most diverse family of galatheoids and it is commonly reported from the continental slope across the Indian and Pacific Oceans. Examination of material collected by the NOAA RV Townsend Cromwell Cruise near Christmas (Kiritimati) Island, Kiribati, revealed the existence of a new species of Paramunida (P. haigae), which represents the fourth record of the genus for the Central Pacific. Furthermore, recent efforts to unravel phylogenetic relationships and diversification patterns in Paramunida revealed P. granulata (Henderson, 1885) to be the most basally diverging taxon within the genus. This species is clearly distinguished from other species of Paramunida by the spinulation of the carapace and the length of the distomesial spine of the second antennal peduncle article, which in combination with a high level of genetic divergence suggest that this species represents a separate monotypic lineage. A new genus, Hendersonida gen. n., is proposed to accommodate this species based on morphological and molecular evidence. An updated dichotomous identification key for all species of Paramunida is presented.

Colletotrichum caudatum s.l. is a species complex.

Colletotrichum caudatum sensu lato is a widespread fungal pathogen of warm-season grasses. The fungus is easily differentiated from other Colletotrichum species through the presence of a unique filiform appendage at the apex of the conidium. Multi-locus phylogenetic analysis of four DNA sequence markers from 21 isolates of C. caudatum s.l. from six grass hosts recovered the morphospecies as a well-supported monophyletic group. Although closely related to other Colletotrichum species pathogenic to warm-season grasses (e.g. C. sublineola, C. falcatum, C. navitas, C. graminicola), the sister taxon placement of C. caudatum remained unclear. Four major subgroups and three monotypic lineages were identified from the C. caudatum s.l. isolates. Despite the presence of localized, taxon-specific incongruence between gene trees and evidence for recombination in the dataset, application of genealogical concordance species recognition criteria diagnosed the four subgroups as phylogenetic species. Traditional morphology-based species concept defines C. caudatum as one species with a broad host range; however, multi-locus phylogenetic analyses refuted this model. Instead, isolates from different hosts were mainly segregated into different lineages. In particular, isolates from the type locale and host (USA, Sorghastrum nutans) collected within a 400 km radius were divided into three distinct species that corresponded with the three sampling sites. These data established that traditional morphological and ecological features are not informative for recognition of taxa within C. caudatum s.l., although there is some evidence that some species may be host specific. To stabilize the application of the name C. caudatum, DNA sequence data from the lectotype was generated, an epitype strain consistent with the type was designated and illustrated, and an emended description of C. caudatum sensu stricto is provided. Colletotrichum alcornii, C. baltimorense, C. somersetense, and C. zoysiae are described as new morphologically cryptic species related to C. caudatum s.s.

Life history traits and patterns of diversification in oceanic archipelagos: a meta-analysis

Ecological conditions, such as high habitat diversity and the absence of competitors, have been proposed as key determinants of the patterns of speciation observed in oceanic island floras. However, the relationship between plant traits and lineage diversification has received less attention. Here, we review 120 published phylogenetic and population genetic studies of three well-studied oceanic archipelagos (Canary Islands, Galapagos and Hawai'i) to investigate potential associations between life history characters (growth form and fruit type) and patterns of diversification. The available data suggest that the phenotypic syndrome 'herbaceous-dry fruited' was predominant among ancestors of species-rich lineages, although the Hawaiian flora also shows a substantial proportion of 'woody-fleshy fruited' ancestors. Growth form, unlike fruit type, is shown to be a labile character strongly selected for woodiness, particularly in radiating lineages. Dry fruits, although representative of diverse dispersal modes and efficacies, are generally associated with a low incidence of inter-island colonization, and the analysis of population genetic data confirms strong genetic differentiation among islands for dry fruited species of radiating lineages. In contrast, fleshy fruited species of monotypic lineages typically show widespread distributions coupled with extensive gene flow among islands, which probably impedes speciation. Our analyses suggest that fruit types associated with limited evidence of dispersal promote recurrent speciation within lineages, although particular character states related to speciation appear to be context dependent. This study reinforces the idea that plant traits associated with island colonization and population persistence are, in addition to ecological conditions, important factors in understanding the patterns of diversification on islands. © 2013 The Linnean Society of London.

Resolving deep lineage divergences in core corvoid passerine birds supports a proto-Papuan island origin

It is well established that the global expansion of songbirds (Oscines) originated in East Gondwana (present day Australo-Papua), and it has been postulated that one of the main constituent groups, the “core Corvoidea”, with more than 750 species, originated in the first islands that emerged where New Guinea is now located. However, several polytomous relationships remained within the clade, obstructing detailed biogeographical interpretations. This study presents a well-resolved family-level phylogeny, based on a dataset of 22 nuclear loci and using a suite of partitioning schemes and Maximum Likelihood and Bayesian inference methods. Resolving the relationships within the core Corvoidea provides evidence for three well-supported main clades, which are in turn sister to the New Zealand genus Mohoua. Some monotypic lineages, which have previously been considered Incertae sedis, are also placed in a phylogenetic context. The well-resolved phylogeny provides a robust framework for biogeographical analyses, and provides further support for the hypothesis that core corvoids originated in the proto-Papuan island region that emerged north of Australia in the late Oligocene/early Miocene. Thus, the core Corvoidea appear to represent a true island radiation, which successfully colonized all continents except Antarctica.