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The successful management of coral reefs necessitates understanding the genetic characteristics of reefs' populations since levels of genetic diversity play a critical role in their resilience, enabling them to withstand environmental changes with greater efficacy. To assess the genetic diversity and connectivity of the widespread Indo-Pacific coral, Stylophora pistillata, eight microsatellite loci were employed on 380 tissue samples collected from eight sites along the northern Gulf of Eilat, Red Sea. We documented deviations from the Hardy–Weinberg equilibrium and observed low heterozygosity and high values of expected heterozygosity (0.59 and 0.82, respectively). The relatively high FST values and STRUCTURE analysis results showed population fragmentation along the short coastline (<12 km). These results signify isolation by distance, low gene flow between most populations, and possible non-random mating. These results are connected to this species' sexual reproduction traits, a brooding coral species with planulae that settle shortly upon release with limited connectivity that are most probably further exacerbated by anthropogenic impacts imposed on Eilat's reefs. This study provides insights into the connectivity and population genetics of S. pistillata residing in an urbanized northern Red Sea reef and reinforces the need for better management of the current MPA, employing future active coral reef restoration in the area. [ABSTRACT FROM AUTHOR]

The rhizostomatid scyphozoan Rhopilema nomadica is one of the most notorious marine invasive species established in the eastern Mediterranean Sea. Using seven microsatellite loci, here, we examined the population genetic structures on 587 individual tissue samples collected from 21 sites along the Mediterranean coast of Israel over a period of 16 years. The results indicate unique microsatellite landscapes for all samples, which belong to a single unstructured population. The >20 alleles found in most loci, low fixation index (F) values (average 0.106), and high heterozygosity (average 0.667) suggest random or assortative mating. Additionally, the low overall differentiation (Fst) values (0.043) and pairwise Fst values between the samples collected in different years indicated gene flow and random mating over the years, potentially due to the long-lasting podocytes, scyphistomae, and adults causing a population overlap between the sampled months/years. Likewise, analyses were conducted between seasons, sites, and early/intermediate/late periods of collecting years. These results support the previous analyses performed on the mitochondrial gene cytochrome oxidase subunit I (COI) sequences, altogether indicating a highly polymorphic single unstructured R. nomadica population in the Levant, possibly backed by independent introductions. The results hint to the existence of highly functional connectivity with a genetically highly diverse source population. [ABSTRACT FROM AUTHOR]

The world's oceans and seas host >100 known strains of thraustochytrids, a common group of marine eukaryotic unicellular protists, residing in diverse marine habitats, with many others to be isolated and cultivated. The thraustochytrids have become of considerable industrial interest due to health benefits gained from their high percentages of valuable bioactive compounds, revealing the needs for the isolation of new potential strains. Employing a recently developed isolation methodology (use of cell culture medium), we assess initial culture conditions and growth paces of newly isolated thraustochytrid cells (thraustochytrid sp. BSH), originated from the colonial tunicate Botryllus schlosseri, residing on Helgoland Island, Germany. Cells were cultivated under static versus agitated conditions, along with two inoculation sizes (0.5 × 106 and 1 × 106 cells/dish) and in three vessel types (35 mm Petri dishes and T25 and T75 flasks; containing 3, 5 and 15 mL medium, respectively). Cultures were observed under regular microscopy, confocal microscopy and H&E staining. While cells in all conditions grew fast, results revealed the superiority of agitated cultivation in T75 flasks inoculated with 0.5 × 106 cells/dish (6.41 ± 1.91-fold increase/week). Further, 18S rDNA revealed high similarities (99.5–99.8) of strain BSH to two thraustochytrid strains from Monterey, California (USA), B. schlosseri colonies, elucidating a new understanding of these animals-protists associations. [ABSTRACT FROM AUTHOR]

Nineteen microsatellite loci, obtained by the whole genome sequencing approach, were developed and validated for the 'smooth cauliflower' coral Stylophora pistillata, a widespread Indo Pacific branching coral species. A sample size of 40 colonies collected at five reef sites along the northern Gulf of Eilat, the Red Sea, were genotyped, revealing loci reproducibly and suitable outcomes for wide applications, including population genetic studies. The 19 new microsatellite loci in this sample were composed of 4–20 alleles/locus, of which 10 microsatellites are highly polymorphic (≥10 alleles/locus). The observed and expected heterozygosity ranged between 0.289 and 0.957 (mean 0.597) and 0.101 and 0.911 (mean 0.726), respectively, and the Fixation Index (F), which also indicates the inbreeding coefficient, ranges between −0.174 and 0.569 (mean 0.207). The polymorphic information content (PIC) ranges between 0.100 and 0.904 (mean 0.699). This new set of microsatellite loci will be employed for population genetics studies as for identifying the distribution of various genotypes within S. pistillata chimeras. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ydbio.2007.09.005 Byline: Yuval Rinkevich (a), Jacob Douek (b), Omer Haber (a), Baruch Rinkevich (b), Ram Reshef (a) Keywords: Innate immunity; Ascidians; Botrylloides; Development; Serine protease; Regeneration; EST library; Urochordates Abstract: The phenomenon of whole body regeneration (WBR) from minute soma fragments is a rare event in chordates, confined to the subfamily of botryllid ascidians and is poorly understood on the cellular and molecular levels. We assembled a list of 1326 ESTs from subtracted mRNA, at early stages of Botrylloides leachi WBR, and classified them into functional categories. Sixty-seven (15%) ESTs with roles in innate immunity signaling were classified into a broad functional group, a result supported by domain search and RT-PCR reactions. Gene ontology analysis for human homologous to the immune gene category, identified 22 significant entries, of which 'peptidase activity' and 'protease inhibitor activity', stood out as functioning during WBR. Analyzing expressions of serine protease Bl-TrSP, a representative candidate gene from the 'peptidase activity' subgroup, revealed low transcript levels in naA[macron]ve vasculature with upregulated expression during WBR. This was confirmed by in situ hybridization that further elucidated staining restricted to a circulating population of macrophage cells. Furthermore, Bl-TrSP was localized in regeneration niches within vasculature, in regenerating buds, and in buds, during blastogenesis. Functional inhibition of serine protease activity disrupts early remodeling processes of the vasculature microenvironment and hinders WBR. Comparison of genome-wide transcription of WBR with five other developmental processes in ascidians (including metamorphosis, budding and blastogenesis), revealed a broad conservation of immune signaling expressions, suggesting a ubiquitous route of harnessing immune-related genes within a broader range of tunicate developmental context. This, in turn, may have enabled the high diversity of life history traits represented by urochordate ascidians. Author Affiliation: (a) Faculty of Biology, Technion-Israel Institute of Technology, Haifa, Israel (b) Israel Oceanography and Limnological Research, National Institute of Oceanography, Tel Shikmona, Haifa 31080, Israel Article History: Received 9 April 2007; Revised 28 August 2007; Accepted 6 September 2007

The accurate taxonomic identity for the worldwide-distributed invasive ascidian Botryllus schlosseri has not been resolved. Employing molecular tools, primarily mtDNA, previous studies unveiled five divergent clades (A–E), suggesting a complex of five cryptic species. A recent study allocated clades A and E to different species. Here, worldwide B. schlosseri's COI distribution map has been drawn, based on 2927 specimens, elucidating 160 haplotypes (100 singletons). Clade A emerged as the most abundant and globally widespread, while other clades had more limited distributions (primarily B, C). Inter-clade and intra-clade divergences were similar, with no clear barcoding gaps between the clades, illuminating no more than two putative OTUs. Network analyses for the genetic similarities among the clades' haplotypes identified different groups, depending on threshold values and away from the suggested clades' boundaries. Three additional genetic markers (H3, 18S, 28S) disclosed clade A, segregating from other clades and clades D and E strongly integrating. Allorecognition assays between clades resulted in indifference and rejection outcomes, characteristics of the within-species allorecognition repertoire. The question as to whether Botryllus schlosseri is a single species or a species complex is further discussed, leading to the assertion that while it is a widely variable species, there is not enough evidence for its designation as a species complex. [ABSTRACT FROM AUTHOR]

Lophoura edwardsi, a rarely recorded deep-water parasitic copepod, is reported for the first time from the Eastern Mediterranean Sea. We document its incidence of infection in hauls made between 2014 and 2020 on the Israeli upper slope, southeastern Mediterranean Sea. All 15 post-metamorphic females parasitized the deep-water macrourid Coelorinchus caelorhincus. Molecular analysis of 5 specimens revealed four 18S rRNA and four COI haplotypes. Comparisons of 18S rRNA to the Siphonostomatoida sequences available in NCBI confirm L. edwardsi is closely related to the cofamilial Tripaphylus elongatus. The recent emergence of a small but stable population may augur changes in the Levantine slope ecosystem. [ABSTRACT FROM AUTHOR]

An outbreak of the widely invasive mytilid mussel Perna perna is reported off Israel, long after its previously documented ephemeral occurrence in the mid-1960s. No contemporary populations are known east of the Gulf of Tunis, in the central Mediterranean Sea. Four molecular markers, the mitochondrial cytochrome c oxidase subunit I (COI), ribosomal 18S, 28S subunits (18S rRNA, 28S rRNA) and histone H3 have been used to validate samples identities. COI haplotype diversity suggests that the Israeli population is highly polymorphic, originating from multiple propagules. The present extensive beds in Haifa Bay, home to Haifa port, may point to vessel-transported introduction. The dense beds of P. perna may change intertidal habitats and their communities, and cause fouling of coastal infrastructure (e.g. marine outfalls, seawalls, jetties), as well as offshore infrastructure (e.g. offshore terminals, energy production platforms), and may incur heavy maintenance costs. [ABSTRACT FROM AUTHOR]

A single specimen of a pelagiid jellyfish collected next to Ashdod port, Israel, is referred to the genus Chrysaora Péron and Lesueur, 1810 based on molecular examinations. Despite the inability to check morphological features of diagnostic value, molecular analyses based on the mitochondrial barcoding gene cytochrome oxidase sub unit I (COI), 16S and 28S ribosomal DNA reveal marked dissimilarities from both the Northeast Atlantic-Mediterranean native Chrysaora hysoscella (Linnaeus, 1767) and the closest GeneBank/BoLD available congener, the West African C. africana (Vanhöffen, 1902). It is suggested that the species is new to science and non-native to the Mediterranean Sea, possibly the sixth introduced scyphozoan species reported in the Levant Sea. [ABSTRACT FROM AUTHOR]

Based on mtCOI sequences comparisons, recent studies reassigned the ‘dwarf Botrylloides leachii’ from the Levant as Botrylloides nigrum. Here we conducted a survey of the literature and of deposited mtCOI sequences of botryllid ascidians, elucidating ambiguities in their taxonomy. We found that the species, dwarf morph of Botrylloides leachii, Botrylloides nigrum, Botryllus aster and Botryllus arenaceus are grouped together on a single molecular taxon. Then, results of three additional markers (18S, 28S, H3) contradicted literature suggestions, revealing minute distances between Botrylloides leachii and the ‘dwarf Botrylloides leachii’. Moreover, only Botrylloides leachii and the ‘dwarf Botrylloides leachii’ develop giant ampullae as an allorecognition response. Our results raise the possibility that inadequate identification, together with faults in molecular assignment, including queries regarding the efficacy of the mtCOI as the exclusive barcoding tool in botryllid ascidians, is the major culprits responsible for the emerged inconsistencies between the mtCOI sequences and traditional taxonomy. Thus, we assign the Levantine dwarf form as Botrylloides aff. leachii. [ABSTRACT FROM AUTHOR]

This study evaluates the utility of DNA barcoding (mitochondrial cytochrome oxidase subunit I; COI) as a biodiversity and conservation applied tool for identifying fish fauna from the southeastern Mediterranean (the continental coast of Israel), a hot-spot area for biological invasion, also with an eye to establish the foundation for follow-up studies that will use environmental DNA (eDNA) tracks of native and invasive species, and for the application of eDNA concepts and methodologies in nature conservation. We established a dataset of 280 DNA barcodes, representing 110 marine fish species (all identified by a taxonomist), belonging to 75 native and 35 Lessepsian migratory species that were tested within and against the BOLD system database. Most of the query sequences showed 98% matches with reference DNA barcodes in the BOLD system excluding two Trachurus species, three Dasyatis pastinaca and two Rhinobatos rhinobatos individuals. Relatively high intraspecific genetic distances were observed in two Elasmobranchii species (8.83%-18%), suggesting possible cryptic species. In contrast, relatively low interspecific genetic distances were found between two Actinopterygii species (1.54%). Gobiidae family members were observed as being the most scattered on the Bayesian tree. Out of the 110 fish species, 48 were taxonomically discordant with the BOLD BINs (4 at the family level, 15 at the genus level and 29 at the species level), 53 were concordant and 9 were singletons. Discordancy was noted for some Diplodus and Fistularia species during the BOLD BIN analysis. Apogon queketti, Champsodon nudivittis and Cheilodipterus novemstriatus were uploaded to the BOLD system for the first time. We elucidated 177 haplotypes, 122 for the native fish species and 55 for the Lessepsian species. The results will allow the evaluation of invasive species success and will help developing improved policies for the conservation of Mediterranean biodiversity. [ABSTRACT FROM AUTHOR]

Fluorescent-amplified fragment length polymorphism (FAFLP) fingerprinting assay was used to compare the genetic diversity within and between tadpole shrimps (Notostraca) populations ofLepidurus apus(n=7) andTriops cancriformis(n=2) from rain pools in Israel. Each ephemeral water body has revealed a unique fingerprint pattern with an entailed genetic drift between nearby ponds. High similarity of genotypic diversity within each geographic area led to three clusters of water bodies, north, south and center of Israel. FAFLP assays on several newly hatched individuals ofT. cancriformisrevealed high identity amongst kin, as compared toL. apuswhere newly hatched from the same maternal source showed high diversity. Results indicate thatT. cancriformispopulations from Israel are probably parthenogenetic as indicated by clonal structures. The higher genetic variability in theL. apuspopulations and in laboratory-hatched specimens indicates the existence of sexual reproduction. [ABSTRACT FROM AUTHOR]

In a recent article, Malaquias et al. (2016) use molecular tools to test the conspecificity of the aglajid sea slug Chelidonura fulvipunctata Baba, 1938 populations from two sites in the Mediterranean (Cyprus, Italy) and the Indo-West Pacific (Mozambique, Lizard Island, Australia, and Marshall Islands). The authors then postulate that the species has entered the Red Sea from the Mediterranean Sea through the Suez Canal, the latter acting as a “revolving door” that can allow species of Indo-Pacific origin to enter the Mediterranean, and species established in the Mediterranean to move into the Red Sea. In this response evidence is offered that questions, if not refutes, the authors’ premises. The veracity and accuracy of the geographic origin and the pathways of introduction are of major importance for management of bioinvasions. For appropriate management measures to be prioritized, devised, and implemented, care should be taken to provide scientists, regulators and stakeholders with as accurate information as possible. [ABSTRACT FROM AUTHOR]

The patterning of the modular body plan in colonial organisms is termed astogeny, as distinct from ontogeny, the development of an individual organism from embryo to adult. Evolutionarily conserved signaling pathways suggest shared roots and common uses for both ontogeny and astogeny. Botryllid ascidians, a widely dispersed group of colonial tunicates, exhibit an intricate modular life form, in which astogeny develops as weekly, highly synchronized growth/ death cycles termed blastogenesis, abiding by a strictly regulated plan. In these organisms both astogeny and ontogeny form similar body structures. Working on Botryllus schlössen, and choosing a representative gene from each of three key Signal Transduction Pathways (STPs: Wnt/ß-catenin; TGF-ß, MAPK/ERK), we explored and compared gene expression at different stages of ontogeny and blastogenesis. Protein expression was studied via immunohistochemistry, ELISA and Western blotting. Five specific inhibitors and an activator for the selected pathways were used and followed to assess their impact during the blastogenic cycle and the development of distinctive phenotypes. Outcomes show that STPs are activated and function (while not necessarily co-localized) during both ontogeny and astogeny. Cellular patterns in blastogenesis, such as colony architecture, are shaped by these STPs. These results are further supported by administering Wnt agonist and anatagonist, TGF-fS receptor antagonists and inhibitors of Mek1/Mek2. Independent of their expression during ontogeny, some of the spatiotemporal patterns of STPs developed within short blastogenic windows. The results support the notion that while the same molecular machinery is functioning in Botryllus schlössen astogeny and ontogeny, astogenic development is not an ontogenic replicate. [ABSTRACT FROM AUTHOR]

Codium parvulum is a green seaweed (Bryopsidales, Chlorophyta) originally described from the Red Sea. It has not previously been reported from the Mediterranean. Since 2004, however, several blooms of this seaweed have been recorded for the northern shores of Israel. Although C. parvulum may have been present in the eastern Mediterranean and overlooked until now, it seems more likely to be a recent Lessepsian migrant. A collection from the Red Sea (El Gouna, Egypt) is designated the epitype of C. parvulum. [ABSTRACT FROM AUTHOR]

The hyperiidean amphipod Brachyscelus rapacoides Stephensen, 1925 is recorded from the scyphozoan jellyfish Rhopilema nomadica Galil, 1990, a new record of association for the genus Brachyscelus, as well as the first record of hyperiid infestation of a non-indigenous scyphozoan host. Because of some past confusion concerning the status of B. rapacoides and the closely related species B. rapax (Claus, 1871) a redescription of B. rapacoides and molecular analysis are provided in order to validate it as a species distinguished from B. rapax.

A single adult specimen of Gonioinfradens giardi, a portunid crab known from the Red Sea, Gulf of Oman and Arabian Gulf, was recently collected off the southern Israeli coast, in the southeastern Mediterranean Sea. Morphological characters, as well as molecular analyses based on the mitochondrial barcoding gene cytochrome oxidase sub unit I (COI), support its distinction from the widely distributed G. paucidentata. Therefore, G. giardi is reinstated as a valid species, and withdrawn from its synonymy with G. paucidentata. Previous Mediterranean records of the latter species are misidentifications and should be referred to G. giardi. The species is described, illustrated, and differentiated from its cogener.