An examination of organic extracts of four new species of South African latrunculid sponges, Tsitsikamma pedunculata, T. favus, Latrunculia bellae, and Strongylodesma algoaensis, yielded 13 known and eight new pyrroloiminoquinone alkaloids, 3-dihydro-7,8-dehydrodiscorhabdin C (4), 14-bromo-3-dihydro-7,8-dehydrodiscorhabdin C (5), discorhabdin V (6), 14-bromo-1-hydroxydiscorhabdin V (7), tsitsikammamine A N-18 oxime (10), tsitsikammamine B N-18 oxime (11), 1-methoxydiscorhabdin D (12), and 1-aminodiscorhabdin D (13). Standard spectroscopic methods provided the structures of the pyrroloiminoquinone metabolites, while chiral GC-MS analysis of the acylated ozonolysis products of 21 confirmed the stereochemistry of the l-histidine residue in this compound. The anticancer activity of 20 pyrroloiminoquinone compounds was explored in the HCT-116 cancer cell line screen, and the DNA intercalation of the tsitsikammamines, together with their ability to cleave DNA through topoisomerase I inhibition, is discussed.

This review presents the structure, biological activity, biosynthetic studies and, where applicable, references to syntheses of 81 marine alkaloids containing either tetra-, hexa- or octa-hydrogenated variants of pyrrolo[4,3,2-de]quinoline, pyrrolo[4,3,2-de]pyrrolo[2,3-h]quinoline and pyrido[2,3-h]pyrrolo[4,3,2-de]quinoline core skeletons. The literature describing the isolation of pyrroloiminoquinones, and related metabolites, from marine sponges is littered with taxonomic inconsistencies and recent efforts to clarify the taxonomy of the sponges that produce this group of metabolites are discussed.

Background: Methicillin-resistant Staphylococcus aureus (MRSA) PK has been recently identified as a potential novel antimicrobial drug target. Results: Screening of a marine extract library led to the identification of several bis-indole alkaloids as novel potent and selective MRSA PK inhibitors. Conclusion:These results help to understand the mechanism of the antibacterial activities of marine bis-indole alkaloids. Significance: This study provides the basis for development of potential novel antimicrobials.

The NansClim project (2010–2013) represented a regional collaboration to assess the effects of climate on Benguela dynamics. Based on in situ (since the 1960s in Namibia and South Africa and 1985 in Angola) and satellite (since the 1980s) observations, the project focussed on four subsystems, namely the Angola subtropical, northern Benguela upwelling, southern Benguela upwelling and Agulhas Bank. This contribution summarizes the findings for selected key questions, ranging from changes in the physico‐chemical habitats, plankton, pelagic and demersal fish communities, to cross‐cutting evaluation at subsystem and regional scales. The results underline the overriding importance to of considering the combined effects of climate and fishing as drivers of the dynamics of the ecosystem components. Each subsystem currently continues to function largely as a separate entity as described in earlier reviews. However, some changes have been observed across several subsystems, e.g., a coherent shift from one relatively stable period to another occurred in the northern and southern Benguela in the mid‐1990s. Future climate change could weaken the boundaries between the four subystems. The findings underline the need for continued regional research collaboration and regional surveys focussed at ecosystem, rather than resource, assessment. Our conclusions include implications for ecosystem‐based fisheries management, and recommendations for future regional research.

A recent major revision of the Family Latrunculiidae (Demospongiae: Poecilosclerida) recognised four valid genera; Latrunculia du Bocage, Sceptrella Schmidt, Strongylodesma Lévi, and Tsitsikamma Samaai & Kelly, from South Africa. The major diagnostic characters of the Family Latrunculiidae are the possession of discate acanthose microrhabd microscleres called acanthodiscorhabds, or more traditionally, “chessman” spicules, that form a dense palisade in the outer ectosome, a tangential layer of styles or anisostrongyle megascleres below this, and a wispy choanosomal skeleton of the same spicules. The sponge surface almost always has areolate porefields and short fistular oscules. This paper reports new Latrunculiidae from western and southeastern South Africa, including a redescription of Latrunculia biformis (Kirkpatrick). Four key characters, including microsclere ornamentation, spicule dimensions, colouration in life, and surface aquiferous features, define three new species of Latrunculia (L. lunaviridis sp. nov., L. microacanthoxea sp. nov., and L. bellae sp. nov.), two new species of Strongylodesma (S. algoaensis sp. nov. and S. tsitsikammaensis sp. nov.), and two new species of Tsitsikamma (T. pedunculata sp. nov. and T. scurra sp. nov.).

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Free-living marine invertebrates occupy one of two environments as adults -the pelagos or the benthos. Many benthic animals nevertheless occupy the pelagos for a short period of time at some stage in their life, be it as gametes or developing larvae. These temporary components of the plankton are referred to as meroplankton, whilst organisms that remain in the plankton for the full duration of their life are known as holoplankton. The length of time that a life cycle stage is resident in the plankton is related to the trophic mode of that stage. Taxa with lecithotrophic larvae or non-feeding life cycle stages tend to be pelagic for relatively short periods of time, and dispersal is comparatively limited (e.g. Scheltema, 1986). Others have planktotrophic larvae that feed whilst in the plankton, and these may be resident for prolonged periods of time during which they undergo extensive and sometimes complex development and can disperse over much greater distances (e.g. Scheltema, 1986;Avise et al., 1987).The evolution of benthic taxa, because of their obvious association with the seabed and their relatively restricted use of the pelagos, is thought to have been strongly influenced by tectonic and climatic events, and vicariance has been suggested to be the major mechanism leading to allopatric speciation (e.g. Springer, 1982;Heads, 2005). The diversity of the marine benthos is comparatively high, and relatively few species are ABSTRACT Aim Using the genus as the unit of analysis, we examine the relationship between richness, distribution and life cycle strategy for all currently recognized marine Hydrozoa.Location The global marine environment.Methods A global dataset detailing the number of species per genus and the mean date of first description (as a proxy for geographic range size) per genus was assembled for all currently recognized marine Hydrozoa. Differences in means per genus were examined by dominant life cycle strategy (holoplanktic, meroplanktic and benthic) using nonparametric ANOVA and resampling methods.Results By comparison with benthic taxa, holopelagic genera are (on average) significantly less species rich and were described at a significantly earlier date. Taxa with meroplanktic life cycles have a richness and a date of first description that is mid-way between the two extremes.Main conclusions Following from previous work showing that there is a negative relationship between the date of first description and geographic range size, our data indicate that holopelagic taxa not only have fewer species per genus but also have a wider distribution than benthic taxa. These quantitative results are in agreement with long-standing intuitions, and should be applicable to other taxa. They run counter to some recent genetic observations that suggest taxa having planktic larvae might nevertheless show restricted distributions; we argue that this inference reflects a lack of sampling of holopelagic taxa, and a call is made to provide empirical evidence from this realm.