Molecular phylogeny of Camponotus ants in Korea

The molecular phylogeny of 12 species of Camponotus ants in Korea was examined using random amplified polymorphic DNA (RAPD) markers as inputs for an analysis of molecular variance (AMOVA) and cluster analysis to describe the relationships between species. For comparison, morphometric data (based on 10 morphological characters) were also gathered for phylogenetic analysis. Assessments of similarity between species were made, and the results of these assessments are compared for the molecular and morphological data sets. In the morphometric analysis, the following groups were identified: (i) C. atrox, C. kiusuensis, C. japonicus and C. concavus (93% similarity); (ii) C. sp. 1 (be diverging at 80% similarity); (iii) C. jejuensis, C. sp. 3, C. itoi, C. nawai and C. tokioensis (94.5% similarity); and (iv) C. nipponensis and C. quadrinotatus (94.5% similarity). Formica fusca was 73.5% similar to the 12 Camponotus species studied here. The group comprising C. nawai and C. tokioensis had the highest similarity index (97.36%), followed by the group comprising C. jejuensis and C. sp. 3 (95%), then C. atrox and C. kiusuensis (94.5%), and then C. nipponensis and C. quadrinotatus (93.5%). In the molecular analysis the following groups were identified: (i) C. atrox and C. jejuensis (30% similarity); (ii) C. concavus, C. japonicus and C. itoi (25% similarity); (iii) C. kiusuensis, C. nawai, C. sp. 3, C. nipponensis, C. quadrinotatus and C. sp. 1 (24% similarity); and (iv) C. tokioensis (be diverging at 23% similarity). The most closely related group in the molecular analysis was C. nawai and C. sp. 3 (75% similarity), followed by C. concavus and C. japonicus (50.5% similarity), then C. atrox and C. jejuensis (30%), and then C. quadrinotatus and C. sp. 1. Camponotus tokioensis was the least closely related to other species among the 12 species studied. Although C. jejuensis and C. tokioensis were found to be 93.6% similar on the basis of morphometric data, molecular data indicated only 23% similarity, the lowest similarity index between any two species considered here. Camponotus jejuensis has marked morphological similarities to C. tokioensis, but on the basis of molecular data gathered in the present study, we refute the proposal that they are synonyms or sister species.     

Redescription of Favella ehrenbergii (Claparède and Lachmann, 1858) Jörgensen, 1924 (Ciliophora: Choreotrichia), with Phylogenetic Analyses Based on Small Subunit rRNA Gene Sequences

ABSTRACT. The identification of Favella ehrenbergii, a marine planktonic ciliate, has largely been based on its lorica features. This approach is potentially problematic given the polymorphic lorica during this organism's life cycle. We isolated a population of F. ehrenbergii from the coastal waters of Incheon, Korea, and revealed its infraciliature using the protargol staining method. Phylogenetic analysis based on small subunit rRNA gene sequences was also performed. Results showed that this population possessed 16 collar membranelles (CM) and about 100 somatic kineties. These features are highly conserved, even in later dividers. As such, the number of CM and somatic kineties can be used as key characteristics for identification of Favella species.     

Burkholderia species are ancient symbionts of legumes

Burkholderia has only recently been recognized as a potential nitrogen-fixing symbiont of legumes, but we find that the origins of symbiosis in Burkholderia are much deeper than previously suspected. We sampled 143 symbionts from 47 native species of Mimosa across 1800 km in central Brazil and found that 98% were Burkholderia . Gene sequences defined seven distinct and divergent species complexes within the genus Burkholderia . The symbiosis-related genes formed deep Burkholderia -specific clades, each specific to a species complex, implying that these genes diverged over a long period within Burkholderia without substantial horizontal gene transfer between species complexes.     

Molecular cloning and expression profiles of calreticulin gene from the diamondback moth,Plutella xylostella

Calreticulin (CRT) plays pivotal roles in Ca²⁺ homeostasis, molecular chaperoning, infection, inflammation and innate immunity. In an attempt to study the involvement of CRT in innate immunity, the full-length cDNA of calreticulin (PxCRT) was cloned from the diamondback moth, Plutella xylostella. It consists of 1674 bp (excluding poly-A tail) with a longest open reading frame (ORF) of 1197 bp encoding 398 amino acids. In silico analysis of PxCRT ORF reveals that it has various repeat motifs and endoplasmic reticulum retention signal found in all the calreticulin proteins. As expected, high amino acid sequence identities were found from other CRTs identified from Bombyx mori (87%), Galleria mellonella (87%), Apis mellifera (74%), Anopheles gambiae (74%), Tribolium castaneum (73%), Culex quinquefasciatus (73%), Rhodnius prolixus (72%), Nasonia vitripennis (71%), Drosophila melanogaster (71%) and Haemaphysalis qinghaiensis (68%). During development, P. xylostella expressed PxCRT predominantly in the pupal stage. In addition, spatial expression pattern analysis indicates that PxCRT was highly expressed in the silk gland. PxCRT mRNA, furthermore, was strongly induced 3 to 6 h after laminarin treatment, suggesting that PxCRT appears to be involved in immune responses and also plays an important role in the silk gland.     

Miscanthus×giganteus plant regeneration: effect of callus types,ages and culture methods on regeneration competence

The perennial rhizomatous grass, Miscanthus×giganteus is an ideal biomass crop due to its rapid vegetative growth and high biomass yield potential. As a naturally occurring sterile hybrid, M. ×giganteus must be propagated vegetatively by mechanically divided rhizomes or from micropropagated plantlets. Plant regeneration through somatic embryogenesis is a viable approach to achieve large‐scale production of plantlets in tissue culture. Effect of the callus types, ages and culture methods on the regeneration competence was studied to improve regeneration efficiency and shorten the period of tissue culture in M. ×giganteus. Shoot‐forming calli having a yellow or white compact callus with light‐green shoot‐like structures showed the highest regeneration frequency. Percentage of shoot‐forming callus induction from immature inflorescence explants was 41% on callus induction medium containing 13.6 μM 2,4‐d and 0.44 μM benzyladenine (BA). The use of a regeneration medium containing 1.3 μM NAA and 22 μM BA was effective at shortening the incubation period required for plantlet regeneration, with 69% of total regenerated plantlets obtained within 1 month of incubation on regeneration medium. Embryogenic‐like callus morphotype could maintain regeneration competency for up to 1 year as suspension cultures. Field grown regenerated plants showed normal phenotypic development with DNA content and plant heights comparable to rhizome propagated plants. Winter survival rates of the regenerated plants planted in 2006 and 2007 at the University of Illinois South Farm, Urbana‐Champaign, Illinois, were 78% and 56%, respectively.     

Daily and seasonal vertical migration rhythms in Daphnia

1. Clones of Daphnia longispina (O.F.M.), collected from ponds with different levels of predation, were monitored using video techniques in order to test the effects of temperature and visual cues on vertical migration behaviour.
2. Endogenous rhythms were found to have a part in the control of vertical migration in some clones but responses were highly variable.
3. Low temperature caused a marked increase in the amplitude of vertical migration in D. longispina , consistent with field studies.
4. Clones from ponds with fish predators had larger vertical migration amplitudes than clones from ponds with no fish, providing further evidence for the genetic basis of this mechanism.     

Tintinnophagus acutus n. g., n. sp. (Phylum Dinoflagellata), an Ectoparasite of the Ciliate Tintinnopsis cylindrica Daday 1887, and Its Relationship to Duboscquodinium collini Grassé 1952

ABSTRACT. The dinoflagellate Tintinnophagus acutus n. g., n. sp., an ectoparasite of the ciliate Tintinnopsis cylindrica Daday, superficially resembles Duboscquodinium collini Grassé, a parasite of Eutintinnus fraknoii Daday. Dinospores of T. acutus are small transparent cells having a sharply pointed episome, conspicuous eyespot, posteriorly positioned nucleus with condensed chromosomes, and rigid form that may be supported by delicate thecal plates. Dinospores attach to the host via a feeding tube, losing their flagella, sulcus, and girdle to become spherical or ovoid cells. The trophont of T. acutus feeds on the host for several days, increasing dramatically in size before undergoing sporogenesis. Successive generations of daughter sporocytes are encompassed in an outer membrane or cyst wall, a feature not evident in trophonts. Tintinnophagus acutus differs from D. collini in host species, absence of a second membrane surrounding pre‐sporogenic stages, and failure to differentiate into a gonocyte and a trophocyte at the first sporogenic division. Phylogenetic analyses based on small subunit (SSU) ribosomal DNA (rDNA) sequences placed T. acutus and D. collini in the class Dinophyceae, with T. acutus aligned loosely with Pfiesteria piscicida and related species, including Amyloodinium ocellatum, a parasite of fish, and Paulsenella vonstoschii, a parasite of diatoms. Dubosquodinium collini nested in a clade composed of several Scrippsiella species and Peridinium polonicum. Tree construction using longer rDNA sequences (i.e. SSU through partial large subunit) strengthened the placement of T. acutus and D. collini within the Dinophyceae.     

Little known Eucinetidae (Coleoptera: Scirtoidea) in Korea

The beetle family Eucinetidae, represented by Eucinetus haemorrhoidalis (Germar), is newly recorded from southern parts of the Korean Peninsula, extending its distributional range by several hundred kilometers to the south. A habitus photo and illustrations of the diagnostic characters of species are provided.