A molecular phylogenetic approach to the systematics of Cylindropuntieae (Opuntioideae,Cactaceae)

Previous taxonomic schemes for the Cylindropuntieae were re‐evaluated in the light of a molecular phylogeny derived from a Bayesian, maximum‐likelihood and parsimony reconstructions with three plastid regions (atpB‐rbcL, psbA‐trnH and trnK/matK data sets). The reconstruction revealed that Corynopuntia and Grusonia as currently defined were polyphyletic. Quiabentia, Micropuntia, Pereskiopsis and Cylindropuntia were the only genera recovered as monophyletic. Grusonia s.s. (only including G. bradtiana) is nested in a polytomy with the rest of the species of Corynopuntia. Grusonia s.l. (G. bradtiana plus Corynopuntia) and Corynopuntia as currently defined are polyphyletic because G. pulchella is sister to Pereskiopsis. Some previous taxonomic proposals for Cylindropuntia and Grusonia recognized polyphyletic series and subgenera that do not conform to the strongly supported monophyletic groups here recovered. This study proposes redefining the polyphyletic Grusonia excluding G. pulchella in order to recognize a strongly supported monophyletic genus and the acceptance of a monotypic Micropuntia (G. pulchella) avoiding a new combination into Pereskiopsis. The infrageneric classification for Grusonia is discussed and the recognition of only four monophyletic strongly supported series (Bigelovianae, Imbricatae, Leptocaules and Ramosissimae) for Cylindropuntia is presented.     

Isolation and characterization of microsatellite loci in Paspalum notatum Flüggé (Poaceae)

Paspalum notatum is a forage grass recognized as one of the major constituents of the native grasslands in the New World. The knowledge of the genetic diversity and structure of P. notatum populations is fundamental for the conservation and germplasm management of this species. About 11 microsatellite markers were isolated from P. notatum and characterized in 25 accessions. The average number of alleles per locus was 7.9 and the PIC ranged from 0.36 to 0.89. The data demonstrated that the most of markers are suitable to detect polymorphism and to study the genetic diversity in the P. notatum species. Moreover, the transferability of these microsatellite were tested on other three congeneric species.     

Host preference and offspring performance are linked in three congeneric hyperparasitoid species

1. The optimisation theory predicts that insect mothers should oviposit on resources on which they attain the highest exclusive fitness. The development of parasitoid wasps is dependent on limited host resources that are often not much larger than the adult parasitoid. 2. In the present study preference and development in three congeneric species of secondary hyperparasitoids attacking cocoons of two congeneric primary parasitoids that differ significantly in size were compared. Gelis agilis (Fabricius) and G. acarorum (L.) are wingless hyperparasitoids that forage in grassy habitats, whereas G. areator (Panzer) is fully winged and forages higher in the canopy of forbs. 3. The three species were reared on cocoons containing pupae of a small gregarious endoparasitoid, Cotesia glomerata (L.), and a larger solitary species, C. rubecula (Marshall), both of which develop in the caterpillars of pierid butterflies. 4. Adult mass was correlated with initial cocoon mass in all three species, whereas development time was unaffected. Wasps were larger when developing in C. rubecula. However, for a given host mass, wasps were larger when developing on the smaller host, C. glomerata. This suggests that there is a physiological limit to hyperparasitoid size that was exceeded when C. rubecula served as host. 5. All three hyperparasitoids strongly preferred to attack cocoons of the larger species, C. rubecula, often avoiding cocoons of C. glomerata entirely. 6. Preference and performance are correlated in the three Gelis species. However, owing to variation in the distribution and thus abundance of their hosts, it is argued that cumulative fitness may be still higher in the smaller host species.     

Does relatedness of natives used for soil conditioning influence plant-soil feedback of exotics?

The naturalisation hypothesis has been gaining attention recently as a possible mechanism to explain variations in invasion success. It predicts that exotic genera with native representatives should be less successful because of an overlap in resource use and of the existence of common specialised enemies. In this study, we tested whether native congenerics have more negative impact on exotic species than heterogenerics by increasing the effects of soil pathogens. We sampled soil in populations of three exotic species (Epilobium ciliatum, Impatiens parviflora and Stenactis annua) at sites with and without respective congeneric species. This soil was used as an inoculum for cultivating the first plant cohort, which included exotics, as well as native congenerics and heterogenerics. The conditioned soil was subsequently used for cultivating the second cohort of plants (exotics only). We found no consistent impact of relatedness of conditioning species on exotic growth. Although soil conditioned by congeneric E. hirsutum had the largest reduction on the performance of E. ciliatum, the final biomass of S. annua was lowest when grown in soil conditioned by itself. There was no effect of stimulating species on the biomass of I. parviflora. In both experimental phases, performance of exotics was improved when cultivated with sterilised inoculua, indicating the dominance of soil generalist pathogens. However, the biomass of S. annua was increased most by congeneric-stimulated inoculum from congeneric sites, suggesting a possible role for specialised symbionts. Our results suggest that variations in invasion success of at least some exotics may be affected by species-specific interactions mediated by the soil biota.     

Development and characterization of microsatellite markers for a mangrove tree species Sonneratia caseolaris (L.) Engler (Lythraceae sensu lato)

Sonneratia caseolaris is a typical non-viviparous mangrove species and a key component of mangrove community in the Indo-West Pacific region. Here we isolated nine microsatellite simple sequence repeat (SSR) loci from the genome of S. caseolaris. Our isolated loci provided SSR markers with polymorphism of 2–6 alleles per locus. The expected and observed heterozygosities ranged from 0.242 to 0.745 and from 0.083 to 0.417, respectively. Cross-species amplification in S. alba and S. ovata showed that a subset of these markers holds promise for these congeneric species. These polymorphic SSR markers would be useful tools for population genetics studies on S. caseolaris as well as other congeneric species.     

Eleven new microsatellite markers for the tropical sea urchin Tripneustes gratilla and cross‐amplification in Tripneustes ventricosa

We describe the isolation, characterization, and application of 11 polymorphic microsatellite loci from the tropical sea urchin Tripneustes gratilla. We genotyped a total of 73 individuals in three subpopulations (two in Hawaii, and one in the Philippines) and found between eight and 33 alleles per locus. We found significant heterozygote deficits within at least one subpopulation at seven out of 11 loci. We were successful at cross‐amplifying four loci in the congeneric Tripneustes ventricosus. When used appropriately, this set of loci will be useful for quantifying population structure in Tripneustes urchins across broad geographical ranges.     

Genetic and reproductive evidence for two species of ornate wobbegong shark Orectolobus spp. on the Australian east coast

This study reports on evidence for reproductive isolation among Orectolobus ornatus and Orectolobus halei, two previously cryptic and recently redescribed species of wobbegong shark (Orectolobiformes: Orectolobidae) from the east coast of Australia. The evidence is based on disparity in size at sexual maturity, diagnostic nuclear and mitochondrial DNA variants, and marked phylogenetic divergence. Plots of total length (L_T) and maturity for the two species were non‐overlapping and illustrative of statistically significant size dimorphism. Genetic analyses and phylogenetic reconstruction did not provide indication of hybridization between O. ornatus and O. halei. In fact, sequence divergence between them was higher than in comparisons with another congeneric and largely co‐distributed wobbegong species (Orectolobus maculatus). The assumption of a molecular clock revealed that the two species have evolved in isolation for c. 3·9 million years. These results challenge a paradigm often mentioned in the biodiversity literature that most cryptic species are the product of recent speciation events and will contribute to the development of effective management strategies for wobbegong sharks.     

Microsatellite loci for the Australian field cricket Teleogryllus oceanicus and their cross‐utility in Teleogryllus commodus

Microsatellite loci were isolated from the Australian field cricket Teleogryllus oceanicus. Seven polymorphic loci were found with an observed number of alleles ranging from eight to 17 and observed heterozygosities between 0.26 and 0.94. One locus was found to be X‐linked. These seven loci were also tested for amplification and polymorphism in the congeneric species Teleogryllus commodus. The loci will be used for paternity studies in these species.     

Polymorphic microsatellites in two different species of the genus Zoogoneticus Meek, 1902 (Goodeidae,Actynopterygii)

This report describes the characterization of 13 microsatellites in Zoogoneticus tequila, a goodeid fish that is extinct in nature and exists only in captivity. We also present a preliminary survey of the variability of nine of these microsatellites in both Z. tequila and the congeneric wild species Z. quitzeoensis. Variability was found to be low in Z. tequila (three polymorphic loci with two alleles each), and highest in Z. quitzeoensis (five polymorphic loci with a mean of 4.6 alleles). These genetic markers have applications in the study and management of both species.     

Male Killing and Incomplete Inheritance of a Novel <Emphasis Type="Italic">Spiroplasma</Emphasis> in the Moth <Emphasis Type="Italic">Ostrinia zaguliaevi</Emphasis>

Bacteria of the genus Spiroplasma are widely found in plants and arthropods. Some of the maternally transmitted Spiroplasma endosymbionts in arthropods are known to kill young male hosts (male killing). Here, we describe a new case of Spiroplasma-induced male killing in a moth, Ostrinia zaguliaevi. The all-female trait caused by Spiroplasma was maternally inherited for more than 11 generations but was spontaneously lost in several lineages. Antibiotic treatment eliminated the Spiroplasma infection and restored the 1:1 sex ratio. The survival rates and presence/absence of the W chromosome in the embryonic and larval stages of O. zaguliaevi showed that males were selectively killed, exclusively during late embryogenesis in all-female broods. Based on phylogenetic analyses of 16S rRNA, dnaA and rpoB gene sequences, the causative bacteria were identified as Spiroplasma belonging to the tick symbiont Spiroplasma ixodetis clade. Electron microscopy confirmed bacterial structures in the follicle cells and follicular sheath of adult females. Although many congeneric Ostrinia moths harbor another sex ratio-distorting bacterium (Wolbachia), only O. zaguliaevi harbors Spiroplasma.     

Molecular phylogenetic analyses of the Japanese Ulva and Enteromorpha (Ulvales, Ulvophyceae), with special reference to the free-floating Ulva

In order to elucidate the species composition of free‐floating Ulva that cause green tide in several bays in Japan, and to clarify the generic status of Ulva and Enteromorpha (Ulvales, Ulvophyceae), the nuclear encoded internal transcribed spacer (ITS) region including the 5.8S gene and the plastid encoded large subunit of ribulose‐1, 5‐bisphosphate carboxylase/ oxgenase (rbcL) gene sequences for 15 species were determined. Both ITS and rbcL analyses indicate that free‐floating Ulva samples are divided into four different lineages that correspond to Ulva lactuca Linnaeus, U. pertusa Kjellman, U. armoricana Dion etal. and U. fasciata Delile. These four species are distinguished by cell morphology including the arrangement of cells, the shape and size of cells and the position of chloroplasts. Molecular data also indicated that Ulva and Enteromorpha are not separated as respective monophyletic groups within a large monophyletic clade and congeneric as shown by previous molecular studies using the ITS sequences alone. This strongly suggests that these genera are congeneric and Enteromorpha should be reduced to the synonym of Ulva.     

Phylogeny and taxonomic reassessment of pikas Ochotona pallasii and O. argentata (Mammalia,Lagomorpha)

We examined a cranial morphometric data set consisting of 186 specimens from the entire distribution range of Ochotona pallasii sensu lato and O. argentata, as well as 67 complete sequences of the COI gene and 28 sequences of the MGF and PRKCI introns from these and closely allied species. Our results show that the two allopatric morphologically similar taxa composing O. pallasii sensu lato – from Mongolia and adjacent territories and Kazakhstan – are paraphyletic relative to O. argentata. Genetic distances between these three taxa are larger than the intraspecific variation known for the subgenus Pika, in which the species under consideration belong; these distances are even larger than the interspecific differences among closely related species such as O. hyperborea, O. mantchurica and O. hoffmanni. Thus, the three focal taxa are recognized here as distinct species. Inspection of the type specimen of O. pallasii indicated that this specimen was not collected in Kazakhstan, has previously been theorized. The most probable place of the holotype's origin is Russian south‐eastern Altai (Chuyskaya Steppe); whatever its exact origin, it definitively originates from the ‘Mongolian’ taxon. Based on this evidence, the senior synonym for the Kazakh pika is O. opaca Argyropulo, 1930. Thus, we propose to recognize three separate species in the O. pallasii species group: O. pallasii (Mongolia and adjacent territories), O. opaca (eastern Kazakhstan) and O. argentata (Helan Shan Range, China).     

The evolution of social parasitism in <Emphasis Type="Italic">Acromyrmex</Emphasis> leaf-cutting ants: a test of Emery’s rule

Summary Emerys rule predicts that social parasites and their hosts share common ancestry and are therefore likely to be close relatives. Within the leaf-cutting ant genus Acromyrmex, two taxa of social parasites have been found, which are thought to occupy opposite grades of permanent social parasitism, based on their contrasting morphologies: Acromyrmex insinuator differs little in morphology from its free-living congeneric host species and produces a worker caste, and is thus thought to represent an early grade of social parasitism. At the other extreme, Pseudoatta spp. exhibit a very specialised morphology and lack a worker caste, both of which are characteristics of an evolutionarily derived grade of social parasitism. Here we present a molecular phylogeny using partial sequences of cytochrome oxidase I and II of about half of the known Acromyrmex species including two social parasites, their hosts and all congeneric species occurring sympatrically. We show that the two inquiline parasites represent two separate origins of social parasitism in the genus Acromyrmex. The early-grade social parasite A. insinuator is highly likely to be the sister species of its host Acromyrmex echinator, but the derived social parasite Pseudoatta sp. is not the sister species of its extant host Acromyrmex rugosus.Received 18 November 2002; revised 16 July 2003; accepted 24 July 2003.     

Microsatellite DNA loci from the drought desert plant Calligonum mongolicum Turcz. (Polygonaceae)

Calligonum mongolicum Turcz. (Polygonaceae) is a typical drought desert plant which can tolerate extreme drought, cold, and other stress in the northern extreme drought desert of China. They are playing an important role in maintaining the local ecosystems in these regions. In order to understand the adaptive evolution and develop effective conservation methods of this species in the arid habitats, it is important to know its genetic structure. In this study, 14 polymorphic microsatellite loci were isolated and characterized from an enrichment genomic library of this species. We further assessed the polymorphisms of each locus in 18 individuals from six geographically distant populations. The number of alleles per locus ranged from three to six. The observed and expected heterozygosity ranged from 0.24 to 0.35 and 0.38 to 0.57, respectively. These markers have been crossed checked in another congeneric species, C. mongolicum. These microsatellite markers will be useful for investigating the genetic structure and devising conservation strategies of this species, and morphological divergence between and it and the closely related species.     

Isolation and characterization of polymorphic microsatellite loci in the field vole,Microtus agrestis,and their cross‐utility in the common vole,Microtus arvalis

We developed nine polymorphic microsatellite loci for the field vole, Microtus agrestis. The number of alleles ranged from five to 15 and observed heterozygosities ranged from 0.40 to 1.00. We also tested the microsatellite loci for amplification and polymorphism in the congeneric species Microtus arvalis. Five of the nine loci were successfully analysed in this species. The microsatellite markers will be employed in studies of reproductive success and fine‐scale spatial genetic structure.     

Isolation and characterization of polymorphic microsatellite markers in <Emphasis Type="Italic">Cupressus </Emphasis><Emphasis Type="Italic">chenggiana</Emphasis> S. Y. Hu (Cupressaceae)

Cupressus chenggiana S. Y. Hu (Cupressaceae) is an endemic and endangered conifer species in southwest China. In order to study the population genetics and design the effective conservation methods, we aimed to develop microsatellite primers for this species in the present study. We developed eight new microsatellite loci for this species through biotin capture method. Polymorphism of each locus was further assessed in 18 individuals from three geographically distant populations. The number of alleles per locus ranged from 6 to 11 with an average of 8.13. The observed and expected heterozygosities ranged from 0.219 to 0.296 and from 0.374 to 0.470, with averages of 0.254 and 0.417, respectively. We further found that three of nine microsatellite loci developed previously for another congeneric species showed polymorphic banding patters. We performed primer-crossing tests of these loci in the other two congeneric species which are closely related to C. chenggiana (C. gigantea and C. duclouxiana). These microsatellite markers would be effective for analyzing genetic diversity and population genetic structure of this species and its morphological differentiation with the close relatives.     

Microsatellite Loci from Lanyu Scops Owl (Otus elegans botelensis) and their Cross-Species Application in Four Species of Strigidae

We developed six new microsatellite markers containing tetranucleotide repeat motifs (GATA/CTAT) for Lanyu scops owl (Otus elegans botelensis) from an enriched partial library. All these loci are polymorphic and conform to Hardy–Weinberg equilibrium. We cross-species tested these and 12 other microsatellite primer pairs previously developed from O. elegans on four other species of owls (O. lettia, O. spilocephalus, O. scops, and Ninox scutulata). Results showed that the degree of polymorphism decreased with increasing phylogenetic distance to O. elegans. Most loci (66.7, 83.3, and 100%) were polymorphic in the three Otus owls but only five (27.8%) were polymorphic in N. scutulata. These microsatellites should be very useful genetic markers in studying the mating system, population genetics, and conservation of other little studied Old World Otus owls.     

A set of polymorphic nuclear intron markers for conservation genetics and phylogeography of <Emphasis Type="Italic">Euphorbia</Emphasis> species (<Emphasis Type="Italic">Pedilanthus</Emphasis> clade)

We developed seven nuclear intron markers for Euphorbia lomelii. New exon-primed intron-crossing (EPIC) oligonucleotides were used for initial amplification and sequencing, then locus-specific primers and restriction-fragment-length polymorphism genotyping assays were designed. Loci showed no significant deviation from Hardy–Weinberg and linkage equilibrium, and they cross-amplify in at least three congeneric species. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Highlighting convergent evolution in morphological traits in response to climatic gradient in African tropical tree species: The case of genus Guibourtia Benn.

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