A Taxonomic Revision of the Mascarene Hibiscus sect. Lilibiscus (Malvaceae), with Morphometric Analysis and Description of Two New Species

Background: The Lethrinidae (emperors) include many important food fish species. Accurate determination of species and stocks is important for fisheries management. The taxonomy of the genus Lethrinus is problematic, for example with regards to the identification of the thumbprint emperor Lethrinus harak. Little research has been done on L. harak diversity in the Pacific and Indian Oceans. This study aimed to evaluate the morphometric and genetic characters of the thumbprint emperor, L. harak (Forsskål, 1775) in the Pacific and Indian Oceans. Methods: This research was conducted in the Marine Biology Laboratory, Faculty of Marine Science and Fisheries, Hasanuddin University, and Division of Fisheries Science, University of Miyazaki. Morphometric character measurements were based on holotype character data, while genetic analysis was performed on cytochrome oxidase subunit I (COI) sequence data. Morphometric data were analysed using principal component analysis (PCA) statistical tests in MINITAB, and genetic data were analysed in MEGA 6. Results: Statistical test results based on morphometric characters revealed groupings largely representative of the Indian and Pacific Oceans. The Seychelles was separated from other Indian Ocean sites and Australian populations were closer to the Pacific than the Indian Ocean group. The genetic distance between the groups was in the low category (0.000 - 0.042). The phylogenetic topology reconstruction accorded well with the morphometric character analysis, with two main L. harak clades representing Indian and Pacific Ocean, and Australia in the Pacific Ocean clade. Conclusions: These results indicate that the morphological character size of L. harak from Makassar and the holotype from Saudi Arabia have changed. Genetic distance and phylogeny reconstruction are closely related to low genetic distance.

Background: The Lethrinidae (emperors) include many important food fish species. Accurate determination of species and stocks is important for fisheries management. The taxonomy of the genus Lethrinus is problematic, for example with regards to the identification of the thumbprint emperor Lethrinus harak. Little research has been done on L. harak diversity in the Pacific and Indian Oceans. This study aimed to evaluate the morphometric and genetic characters of the thumbprint emperor, L. harak (Forsskål, 1775) in the Pacific and Indian Oceans. Methods: This research was conducted in the Marine Biology Laboratory, Faculty of Marine Science and Fisheries, Hasanuddin University, and Division of Fisheries Science, University of Miyazaki. Morphometric character measurements were based on holotype character data, while genetic analysis was performed on cytochrome oxidase subunit I (COI) sequence data. Morphometric data were analysed using principal component analysis (PCA) statistical tests in MINITAB, and genetic data were analysed in MEGA 6. Results: Statistical test results based on morphometric characters revealed groupings largely representative of the Indian and Pacific Oceans. The Seychelles was separated from other Indian Ocean sites and Australian populations were closer to the Pacific than the Indian Ocean group. The genetic distance between the groups was in the low category (0.000 - 0.042). The phylogenetic topology reconstruction accorded well with the morphometric character analysis, with two main L. harak clades representing Indian and Pacific Ocean, and Australia in the Pacific Ocean clade. Conclusions: These results indicate that the morphological character size of L. harak from Makassar and the holotype from Saudi Arabia have changed. Genetic distance and phylogeny reconstruction are closely related to low genetic distance.

Background: The Lethrinidae (emperors) include many important food fish species. Accurate determination of species and stocks is important for fisheries management. The taxonomy of the genus Lethrinus is problematic, for example with regards to the identification of the thumbprint emperor Lethrinus harak. Little research has been done on L. harak diversity in the Pacific and Indian Oceans. This study aimed to evaluate the morphometric and genetic characters of the thumbprint emperor, L. harak (Forsskål, 1775) in the Pacific and Indian Oceans. Methods: This research was conducted in the Marine Biology Laboratory, Faculty of Marine Science and Fisheries, Hasanuddin University, and Division of Fisheries Science, University of Miyazaki. Morphometric character measurements were based on holotype character data, while genetic analysis was performed on cytochrome oxidase subunit I (COI) sequence data. Morphometric data were analysed using principal component analysis (PCA) statistical tests in MINITAB, and genetic data were analysed in MEGA 6. Results: Statistical test results based on morphometric characters revealed groupings largely representative of the Indian and Pacific Oceans. The Seychelles was separated from other Indian Ocean sites and Australian populations were closer to the Pacific than the Indian Ocean group. The genetic distance between the groups was in the low category (0.000 - 0.042). The phylogenetic topology reconstruction accorded well with the morphometric character analysis, with two main L. harak clades representing Indian and Pacific Ocean, and Australia in the Pacific Ocean clade. Conclusions: These results indicate that geographical and environmental factors can affect the morphometric and genetic characteristics of L. harak.

The time-space evolution of the El Niño-Southern Oscillation in sea surface temperature (SST) and heat storage of the upper 400 m (HS400) for the Pacific, Indian, and Atlantic Oceans is investigated for 13 years (1979–1991). EOF and rotated EOF (Varimax or VRX) analyses are performed using the time series of normalized anomalies for each ocean separately and then for the global ocean. In the Pacific and Indian Oceans, the two dominant EOF modes for both SST and H5400 are associated with ENSO. For SST they account for 49% of the total variance in each mean, while for H5400 they account for over 35% of the total variance in each ocean. In the Pacific Ocean, the first EOF modes for SST and HS400 display peak values during spring-summer of 1983 and 1987. They are characterized by maximum positive loadings (or warmer temperature) in the eastern and central Pacific Ocean straddling the equator. These modes represent the peak phase of El Niño off the west coast of South America. The second modes for SST and HS400 are precursor modes with maximum positive loadings in the western and central Pacific Ocean both on and off the equator. The peak values in HS400 second mode lead peak values in HS400 first mode by 6–9 months. Taken together, SST and HS400 first two modes are associated with slow equatorial and eastward propagation of ENSO signals, more clearly though in HS400 than in the SST. In the Indian Ocean, the dominant EOF modes for SST display peak values in summer-fall of 1983 and summer of 1987, while peak values for HS400 are found during fall of 1982 and summer of 1987. Corresponding positive SST loadings are found in the central Indian Ocean while positive HS400 loadings are found in the western Indian Ocean. Maximum values are both straddling the equator. As in the Pacific Ocean, the second EOF modes for SST and HS400 in the Indian Ocean are precursor modes to the first modes. They occur 9–15 months earlier, with warmer SST in the Arabian Sea, colder SST northwest of Australia, and colder H5400 in the vicinity of the boreal winter ITCZ. Taken together, thew two modes suggest a slow equatorial and eastward propagation of ENSO signals in SST and HS400, very similar to those in the Pacific Ocean. This propagation can he seen extending eastward south of Indonesia and on into the Timor Sea. There the anomalies have the same sign as the anomalies found in the Philippine and Coral Seas in the western tropical Pacific Ocean during the peak phase of El Niño. In the Atlantic Ocean, ENSO is represented by the third SST VRX mode but not at all in HS400. As such, the Atlantic ENSO signal at the equator is a passive response to a globally perturbed atmosphere. It lags by approximately 18 months the dominant Pacific ENSO mode.

The genome size, protein (24 loci) and morphological variation in three currently recognized species of the Bufo bufo group was studied. Among common toads of the Caucasian Isthmus, two distinct groups were revealed. The main territory of the Caucasian region, including the Great Caucasian Range and the Caucasus Minor, is inhabited by the Caucasian toad, B. verrucosissimus , whereas the Talysh Mountains, geographically isolated in the south-east of the region, harbor another toad. Genetic distances between these forms were higher ( D = 0.411) than that between B. verrucosissimus and European B. b. bufo ( D = 0.138). Based on genome size and allozyme data, we recognized the Talysh toad as a new distinct species, Bufo eichwaldi , sp. nov. The time of origin of the species estimated on the basis of molecular data, roughly corresponds to relict character of the Hyrcanian forest of the Talysh region (the late Miocene). West Palearctic species ( B. bufo , B. verrucosissimus , B. eichwaldi , sp. nov.) form joint cluster which is separated from another phylogenetic lineage with the Far Eastern B. gargarizans . Taxonomic status of B. verrucosissimus and B. b. spinosus is discussed. The Caucasian toad was treated tentatively as an allopatric species in respect to B. b. bufo of boreal Europe. Common toads of Anatolian Turkey previously recognized as B. b. spinosus were assigned to B. verrucosissimus . The Balkan common toads seems to be a distinct taxon which is the sister lineage of the B. verrucosissimus cluster. Toads from Apennine Peninsula were allocated to distinct subspecies B. b. palmarum . North African (Tunisian) B. b. spinosus was separated as a distinct phyletic lineage forming with B. eichwaldi , sp. nov., the sister group of other West Palearctic common toads. Further resolution of the taxonomic position of that and some other members of the Bufo bufo group needs careful examination of samples from Mediterranean area, including the type locality of B. b. spinosus .

Eriophyoid species belonging to the genus Trisetacus are economically important as pests of conifers. A narrow host specialization to conifers and some unique morphological characteristics have made these mites interesting subjects for scientific inquiry. In this study, we assessed morphological and genetic variation of seven Trisetacus species originating from six coniferous hosts in Poland by morphometric analysis and molecular sequencing of the mitochondrial cytochrome oxidase subunit I gene and the nuclear D2 region of 28S rDNA. The results confirmed the monophyly of the genus Trisetacus as well as the monophyly of five of the seven species studied. Both DNA sequences were effective in discriminating between six of the seven species tested. Host-dependent genetic and morphological variation in T. silvestris and T. relocatus, and habitat-dependent genetic and morphological variation in T. juniperinus were detected, suggesting the existence of races or even distinct species within these Trisetacus taxa. This is the first molecular phylogenetic analysis of the Trisetacus species. The findings presented here will stimulate further investigations on the evolutionary relationships of Trisetacus as well as the entire Phytoptidae family.

On the influence of the Norwegian-Greenland and Weddell seas upon the bottom waters of the Indian and Pacific oceans

In the last decade, a great deal of attention has been paid to the irregular interannual oscillation, known to the acronym writers as ENSO, or El Niño–Southern Oscillation. Algorithms have been developed which model the interaction between the ocean and the atmosphere, and because of the dependency of such modelling on the state of the oceans, various attempts have been made to predict the sea‐surface temperature (SST) anomalies and, further, to understand the relationship between the oceans and their role in the global propagation of the ENSO signal. To this end, a statistical study, using singular value decomposition (SVD), has been made of the relationship between the SSTs of the Pacific and Indian Oceans in the last 4 decades and, in particular, the changes which have taken place, especially in the Indian Ocean. The point of using SVD is that it enables the user to compare the Pacific and Indian Oceans as two separate entities with different dimensions, not one as an adjunct of the other. For the purpose of this analysis, it is assumed that the two oceans are distinct and have separate characteristics. A simple EOF analysis treating the two oceans as one tropical system, for example, would not accomplish this objective. While SVD analyses in meteorology and climatology have mainly been applied to two different meteorological parameters, for example SST and sea level pressure, in the same area, there is no valid reason why SVD should not be applied to the same (or different) parameter(s) in different regions. Although the Indian and Pacific Oceans are of different dimensions, SVD does not weight the result in favour of either the smaller or the larger of the two. SVD is a statistical tool which gives results comparable with canonical correlation analysis, though several authors warn against its indiscriminate use. It is found that the Indian Ocean SSTs have a strong association with Pacific Ocean SSTs, particularly when the Indian Ocean lags the Pacific Ocean by one season in mid‐summer. It is also found that there is a distinct change in the SST patterns in the equatorial Indian Ocean in the second half (1977–1996) of the period under study. Copyright © 2001 Royal Meteorological Society

Baculoviruses (Baculoviridae) are double-stranded DNA viruses which infect the larval stages of insects belonging to the orders Lepidoptera, Hymenoptera and Diptera. Due to their narrow host range and high virulence to target insects, different baculoviruses have been used as biological control agents in pest control. Severe soil pests of many agricultural and horticultural crops, which are difficult to be controlled, are larvae of the genus Agrotis (Lepidoptera: Noctuidae), also called cutworms. Their habitat is the soil or soil surface where they feed on seedlings, stems, and other parts of plants. So far, cutworms are mainly control by chemical pesticides, but biological control agents would be highly desirable for environmental reasons. Two of the most important cutworm pests are the common cutworm, Agrotis segetum (Denis & Schiffermuller), and the black cutworm, A. ipsilon (Hufnagel). At least four distinct baculovirus species, three of the genus Alphabaculovirus and one of the genus Betabaculovirus, were isolated from these two cutworm species. The alphabaculoviruses are the Agrotis segetum nucleopolyhedrovirus A (AgseNPV-A), Agrotis segetum nucleopolyhedrovirus B (AgseNPV-B), and Agrotis ipsilon nucleopolyhedrovirus (AgipNPV). The Agrotis segetum granulovirus (AgseGV) represents the betabaculovirus. Together with their two host species, from which they were first isolated and characterized, they form the so-called Agrotis baculovirus complex. Agrotis baculoviruses have the potential to be used as biological control agents for the control of Agrotis cutworms. However, in-depth knowledge and a full characterization of their biology, molecular setup, and virulence parameters are required for a successful registration and application in the field. In this study the genome sequence of AgseNPV-B was fully sequenced. Its genome is 148,981 bp in length and codes for 150 putative open reading frames. Whole genome comparisons with AgseNPV-A and AgipNPV, whose genome sequences have been published previously, suggested that AgseNPV-B belongs to a new species of the Agrotis baculovirus complex. Phylogenetic analysis indicated a very close relationship to AgipNPV and it could be concluded that both viruses are two distinct species at an early stage of separation. Whole genome alignments revealed a different number of viral enhancing factor (vef) gene copies in AgseNPV-A, AgseNPV-B and AgipNPV as one of the most striking distinguishing features between their genomes. VEFs are known to affect the virulence of baculoviruses. A putative site of genomic recombination was found in the region of the cathepsin and chitinase genes where the high co-linearity of the genomes of all three Agrotis nucleopolyhedroviruses was interrupted by inversions, deletions, or insertions. A putative fifth Agrotis baculovirus, the Agrotis exclamationis nucleopolyhedrovirus (AgexNPV), was suggested to be an isolate of AgseNPV-B due to high nucleotide sequence similarities of partial genomic regions. Based on the genome sequences of AgseNPV-A, AgseNPV-B, AgipNPV and AgseGV a multiplex PCR based method for the identification of these Agrotis baculoviruses was established. Highly specific oligonucleotide primers specific for the polyhedrin (polh) or granulin (gran) genes of the four viruses were developed and resulted in discriminating PCR fragments. Furthermore, this method allowed the quantitation of AgseGV and AgseNPV-B by quantitative PCR (qPCR). Since co-infections of AgseGV and AgseNPV-B have been observed and a combination of both viruses was considered as a combined biological control agent, the potential interaction of both viruses in mixed infections was investigated. Potential interactions between AgseNPV-B and AgseGV were examined in activity studies using single virus as well as combined virus infections of neonate A. segetum larvae. Mortality rates were determined and the virus progeny produced in individual larvae was quantified by using the newly established qPCR method of quantitation of AgseNPV-B and AgseGV. As a result, combinations of AgseNPV-B and AgseGV did not exhibit an advantageous effect in terms of pest control. Neither an increase in mortality rates in mixed virus treatments in comparison with single virus treatments, nor an increase in production of AgseNPV-B or AgseGV progeny in coinfected larvae was observed. On the contrary, a competitive behavior of both viruses in mixed infections could be concluded. The present thesis contribute to the biological control of Agrotis cutworms by providing extensive insight into the molecular setup of these viruses and the characterization of AgseNPV-B as a new Alphabaculovirus species. The use and registration of baculoviruses as biocontrol agents rely on such virus characterizations as well as on virus activity studies that were performed for AgseNPV-B and AgseGV. The new technique in Agrotis baculovirus detection and quantitation will facilitate future single and mixed infection studies of AgseNPV-B and AgseGV, as well as other combinations of Agrotis baculoviruses. Auf Wunsch des Autors / der Autorin ist diese Dissertation nur als Druckausgabe verfugbar.

Genetic diversity and morphological variation in African boxthorn (Lycium ferocissimum) – Characterising the target weed for biological control

Hybrid zones are natural laboratories for investigating the dynamics of gene flow, reproductive isolation, and speciation. A predominant marine hybrid (or suture) zone encompasses Christmas Island (CHR) and Cocos (Keeling) Islands (CKE), where 15 different instances of interbreeding between closely related species from Indian and Pacific Oceans have been documented. Here, we report a case of hybridization between genetically differentiated Pacific and Indian Ocean lineages of the three‐spot dascyllus, Dascyllus trimaculatus (Rüppell, 1829). Field observations indicate there are subtle color differences between Pacific and Indian Ocean lineages. Most importantly, population densities of color morphs and genetic analyses (mitochondrial DNA and SNPs obtained via RADSeq) suggest that the pattern of hybridization within the suture zone is not homogeneous. At CHR, both color morphs were present, mitochondrial haplotypes of both lineages were observed, and SNP analyses revealed both pure and hybrid genotypes. Meanwhile, in CKE, the Indian Ocean color morphs were prevalent, only Indian Ocean mitochondrial haplotypes were observed, and SNP analysis showed hybrid individuals with a large proportion (~80%) of their genotypes assigning to the Indian Ocean lineage. We conclude that CHR populations are currently receiving an influx of individuals from both ocean basins, with a greater influence from the Pacific Ocean. In contrast, geographically isolated CKE populations appear to be self‐recruiting and with more influx of individuals from the Indian Ocean. Our research highlights how patterns of hybridization can be different at scales of hundreds of kilometers, due to geographic isolation and the history of interbreeding between lineages.

The Pacific and Indian Oceans are connected by an oceanic passage called the Indonesian Throughflow (ITF). In this setting, modes of climate variability over the two oceanic basins interact. El Niño–Southern Oscillation (ENSO) events generate sea surface temperature anomalies (SSTAs) over the Indian Ocean that, in turn, influence ENSO evolution. This raises the question as to whether Indo-Pacific feedback interactions would still occur in a climate system without an Indonesian Throughflow. This issue is investigated here for the first time using a coupled climate model with a blocked Indonesian gateway and a series of partially decoupled experiments in which air–sea interactions over each ocean basin are in turn suppressed. Closing the Indonesian Throughflow significantly alters the mean climate state over the Pacific and Indian Oceans. The Pacific Ocean retains an ENSO-like variability, but it is shifted eastward. In contrast, the Indian Ocean dipole and the Indian Ocean basinwide mode both collapse into a single dominant and drastically transformed mode. While the relationship between ENSO and the altered Indian Ocean mode is weaker than that when the ITF is open, the decoupled experiments reveal a damping effect exerted between the two modes. Despite the weaker Indian Ocean SSTAs and the increased distance between these and the core of ENSO SSTAs, the interbasin interactions remain. This suggests that the atmospheric bridge is a robust element of the Indo-Pacific climate system, linking the Indian and Pacific Oceans even in the absence of an Indonesian Throughflow.

The transitions (from relatively strong to relatively weak monsoon) in the tropospheric biennial oscillation (TBO) occur in northern spring for the south Asian or Indian monsoon and northern fall for the Australian monsoon involving coupled land–atmosphere–ocean processes over a large area of the Indo-Pacific region. Transitions from March–May (MAM) to June–September (JJAS) tend to set the system for the next year, with a transition to the opposite sign the following year. Previous analyses of observed data and GCM sensitivity experiments have demonstrated that the TBO (with roughly a 2–3-yr period) encompasses most ENSO years (with their well-known biennial tendency). In addition, there are other years, including many Indian Ocean dipole (or zonal mode) events, that contribute to biennial transitions. Results presented here from observations for composites of TBO evolution confirm earlier results that the Indian and Pacific SST forcings are more dominant in the TBO than circulation and meridional temperature gradient anomalies over Asia. A fundamental element of the TBO is the large-scale east–west atmospheric circulation (the Walker circulation) that links anomalous convection and precipitation, winds, and ocean dynamics across the Indian and Pacific sectors. This circulation connects convection over the Asian–Australian monsoon regions both to the central and eastern Pacific (the eastern Walker cell), and to the central and western Indian Ocean (the western Walker cell). Analyses of upper-ocean data confirm previous results and show that ENSO El Niño and La Niña events as well as Indian Ocean SST dipole (or zonal mode) events are often large-amplitude excursions of the TBO in the tropical Pacific and Indian Oceans, respectively, associated with anomalous eastern and western Walker cell circulations, coupled ocean dynamics, and upper-ocean temperature and heat content anomalies. Other years with similar but lower-amplitude signals in the tropical Pacific and Indian Oceans also contribute to the TBO. Observed upper-ocean data for the Indian Ocean show that slowly eastward-propagating equatorial ocean heat content anomalies, westward-propagating ocean Rossby waves south of the equator, and anomalous cross-equatorial ocean heat transports contribute to the heat content anomalies in the Indian Ocean and thus to the ocean memory and consequent SST anomalies, which are an essential part of the TBO.

This study investigated the occurrence and distribution of cis-eicosenoic acid (c-20:1) positional isomers in fishes from the Indian Ocean and compared to those from the Pacific and Atlantic Ocean. Lipids were extracted from the edible part of the fish and then methylated. The eicosenoic acid methyl ester fraction was separated from total fatty acid methyl esters by reversed-phase HPLC and quantitatively analyzed using a GC-FID fitted with the SLB-IL111 highly polar GC column. c14-20:1 was used as an internal standard. The results indicated that the highest levels of c-20:1 positional isomers were found in fishes from the Pacific Ocean (saury, 166.95±12.4 mg/g of oil), followed by the Atlantic Ocean (capelin, 162.7±3.5 mg/g of oil), and lastly in fishes from the Indian Ocean (goatfish, 34.39 mg/g of oil). With only a few exceptions, the most abundant 20:1 positional isomer found in fishes of the Indian and Atlantic Ocean was the c11-20:1 isomer (>50%) followed by the c13-20:1 isomer (<25%). Unusually, the c7-20:1 isomer was predominantly found in a few fishes such as the tooth ponyfish, longface emperor, and commerson's sole. The c9, c5, and c15-20:1 isomers were the least occurring in fishes from the Indian and Atlantic Ocean. In contrast, the c9-20:1 isomer was the principal isomer identified in fishes from the Pacific Ocean. The results revealed that the content and distribution of c-20:1 positional isomers varied among fishes in different oceans. The data presented in the current study are the first to report on the distribution of c-20:1 positional isomers in fishes from the Indian Ocean.

The relative contributions of the Indian Ocean and Pacific Ocean sea surface temperatures (SSTs) to the rainfall variability over eastern central, and southern Africa during the austral spring‐summer are examined. The variability of African rainfall is statistically related to both oceans, but the variability in the two oceans is also related. To separate the effects of the Indian and Pacific Oceans, a suite of numerical model simulations is presented: GOGA, the atmosphere is forced by observed SSTs globally; IOGA, the atmosphere is forced by observed SSTs only in the Indian Ocean basin; and POGA, the atmosphere is forced by observed SSTs only in the tropical Pacific basin. While the SST variability of the tropical Pacific exerts some influence over the African region, it is the atmospheric response to the Indian Ocean variability that is essential for simulating the correct rainfall response over eastern, central, and southern Africa. Analyses of the dynamical response(s) seen in the numerical experiments and in the observations indicate that the Pacific and Indian Oceans have a competing influence over the Indian Ocean/African region. This competition is related to the influence of the two oceans on the Walker circulation and the consequences of that variability on low‐level fluxes of moisture over central and southern Africa. Finally, given the high correlation found between SST variability in the Indian and Pacific Oceans with the Pacific leading by ∼3 months, we speculate on an approach to long‐lead dynamical climate prediction over central‐east and southern Africa.