Extreme morphologies of mantis shrimp larvae

Larvae of stomatopods (mantis shrimps) are generally categorized into four larval types: antizoea, pseudozoea (both representing early larval stages), alima and erichthus (the latter two representing later larval stages). These categories, however, do not reflect the existing morphological diversity of stomatopod larvae, which is largely unstudied. We describe here four previously unknown larval types with extreme morphologies. All specimens were found in the collections of the Zoological Museum, University of Copenhagen and were collected during the Danish Dana Expedition round the world 1928-30. These new larval types all represent erichthus-type larvae, especially differing in their shield morphologies. The shield morphology ranges from almost spherical to rather disc-like, with sometimes extremely elongated spines, but only a general systematic assignment of the larvae was possible. Further investigations of these larvae are crucial to understand their life habits and ecological impact, especially as stomatopod and other crustacean larvae might have a much more important position in the marine ecosystems than their corresponding adults

A Metabolic Dependency for Host Isoprenoids in the Obligate Intracellular Pathogen Rickettsia parkeri Underlies a Sensitivity to the Statin Class of Host-Targeted Therapeutics.

Gram-negative bacteria in the order Rickettsiales have an obligate intracellular growth requirement, and some species cause human diseases such as typhus and spotted fever. The bacteria have evolved a dependence on essential nutrients and metabolites from the host cell as a consequence of extensive genome reduction. However, it remains largely unknown which nutrients they acquire and whether their metabolic dependency can be exploited therapeutically. Here, we describe a genetic rewiring of bacterial isoprenoid biosynthetic pathways in the Rickettsiales that has resulted from reductive genome evolution. Furthermore, we investigated whether the spotted fever group Rickettsia species Rickettsia parkeri scavenges isoprenoid precursors directly from the host. Using targeted mass spectrometry, we found that infection caused decreases in host isoprenoid products and concomitant increases in bacterial isoprenoid metabolites. Additionally, we report that treatment of infected cells with statins, which inhibit host isoprenoid synthesis, prohibited bacterial growth. We show that growth inhibition correlates with changes in bacterial size and shape that mimic those caused by antibiotics that inhibit peptidoglycan biosynthesis, suggesting that statins lead to an inhibition of cell wall synthesis. Altogether, our results describe a potential Achilles' heel of obligate intracellular pathogens that can potentially be exploited with host-targeted therapeutics that interfere with metabolic pathways required for bacterial growth.IMPORTANCE Obligate intracellular pathogens, which include viruses as well as certain bacteria and eukaryotes, are a subset of infectious microbes that are metabolically dependent on and unable to grow outside an infected host cell because they have lost or lack essential biosynthetic pathways. In this study, we describe a metabolic dependency of the bacterial pathogen Rickettsia parkeri on host isoprenoid molecules that are used in the biosynthesis of downstream products, including cholesterol, steroid hormones, and heme. Bacteria make products from isoprenoids, such as an essential lipid carrier for making the bacterial cell wall. We show that bacterial metabolic dependency can represent a potential Achilles' heel and that inhibiting host isoprenoid biosynthesis with the FDA-approved statin class of drugs inhibits bacterial growth by interfering with the integrity of the cell wall. This work supports the potential to treat infections by obligate intracellular pathogens through inhibition of host biosynthetic pathways that are susceptible to parasitism

A new species of Paramunida Baba, 1988 from the Central Pacific Ocean and a new genus to accommodate P. granulata (Henderson, 1885)

18 páginas, 4 figuras.The genus Paramunida belongs to the most diverse family of galatheoids and it is commonly reported from the continental slope across the Indian and Pacific Oceans. Examination of material collected by the NOAA RV Townsend Cromwell Cruise near Christmas (Kiritimati) Island, Kiribati, revealed the existence of a new species of Paramunida (P. haigae), which represents the fourth record of the genus for the Central Pacific. Furthermore, recent efforts to unravel phylogenetic relationships and diversification patterns in Paramunida revealed P. granulata (Henderson, 1885) to be the most basally diverging taxon within the genus. This species is clearly distinguished from other species of Paramunida by the spinulation of the carapace and the length of the distomesial spine of the second antennal peduncle article, which in combination with a high level of genetic divergence suggest that this species represents a separate monotypic lineage. A new genus, Hendersonida gen. n., is proposed to accommodate this species based on morphological and molecular evidence. An updated dichotomous identification key for all species of Paramunida is presented.PC was funded by Research and Collections, Natural History Museum of Los Angeles County.Peer reviewe

Chapter 11: Vulnerability of benthic invertebrates of the Great Barrier Reef to climate change

This chapter deals with benthic invertebrates inhabiting the extensive inter-reef soft bottom habitats and those occurring on the reef, excluding corals. For the remainder of the chapter, the term ‘benthic invertebrate’ refers to all invertebrates excluding corals. An assessment of the impacts of climate change on non-coral benthic invertebrates poses particular challenges: i) benthic invertebrates include an extraordinary diversity of marine organisms, including many microscopic, infaunal, boring or ephemeral species that can be difficult to sample and are poorly known taxonomically; ii) benthic invertebrates employ a diversity of reproductive strategies, broadly including planktotrophy (development through feeding larvae), lecithotrophy (development through non-feeding larvae) and direct development (release of post-metamorphic juveniles), as well as asexual reproduction, making broad generalisations of dispersal capabilities difficult; iii) factors determining species distributions are poorly known for most species; iv) benthic invertebrates exhibit a tremendous variety of lifestyles and forms, including colonial, sedentary and errant species; v) many species include either a pelagic larval or adult stage, so effects of climate change may vary during their lives (see McKinnon et al. chapter 6 for comments on planktonic forms); and, vi) research on the biogeography of benthic invertebrates on the Great Barrier Reef (GBR) is strongly biased towards commercial or destructive species.This is Chapter 11 of Climate change and the Great Barrier Reef: a vulnerability assessment. The entire book can be found at http://hdl.handle.net/11017/13

Climate Change and invasibility of the Antarctic benthos

Benthic communities living in shallow-shelf habitats in Antarctica (<100-m depth) are archaic in their structure and function. Modern predators, including fast-moving, durophagous (skeleton-crushing) bony fish, sharks, and crabs, are rare or absent; slow-moving invertebrates are the top predators; and epifaunal suspension feeders dominate many soft substratum communities. Cooling temperatures beginning in the late Eocene excluded durophagous predators, ultimately resulting in the endemic living fauna and its unique food-web structure. Although the Southern Ocean is oceanographically isolated, the barriers to biological invasion are primarily physiological rather than geographic. Cold temperatures impose limits to performance that exclude modern predators. Global warming is now removing those physiological barriers, and crabs are reinvading Antarctica. As sea temperatures continue to rise, the invasion of durophagous predators will modernize the shelf benthos and erode the indigenous character of marine life in Antarctica

Catalogue of squat lobsters of the world (Crustacea: Decapoda: Anomura-families Chirostylidae, Galatheidae and Kiwaidae)

220 páginas, 5 figuras, 1 tabla.[EN] This adaptation text reproduces Anexo I of the dissertation “Results”: Sistemática e historia evolutiva de la Familia Galatheidae (Crustacea: Anomura) en el Pacífico Sur, of Patricia Cabezas (2010) http://hdl.handle.net/10261/134771[ES] Este artículo es una adaptación del Anexo I de la tesis doctoral: Sistemática e historia evolutiva de la Familia Galatheidae (Crustacea: Anomura) en el Pacífico Sur, of Patricia Cabezas (2010) http://hdl.handle.net/10261/134771Taxonomic and ecological interest in squat lobsters has grown considerably over the last two decades. A checklist of the 870 current valid species of squat lobsters of the world (families Chirostylidae, Galatheidae and Kiwaidae) is presented. The compilation includes the complete taxonomic synonymy and geographical distribution of each species plus type information (type locality, repository and registration number). The numbers of described species in the world’s major ocean basins are summarised.Peer reviewe

A new genus and two new species of Caprellidae (Crustacea: Amphipoda) from mesophotic and deep-sea waters of Australia

Caprellids from mesophotic and deep-sea waters from Australia have been scarcely studied. A new genus Pseudoliropus gen. nov., and two new species Pseudoliropus keablei and Pseudoprotella australiensis sp. nov. are described based on material collected from 56 to 1125 m deep during surveys on board the vessels RV Sprightly (1973), FRV Kapala (1977–1986) and RV Southern Surveyor (2005) along the coast of the Northern Territory, Queensland, New South Wales, Victoria and Tasmania. Pseudoliropus is superficially very close to Liropus but can be readily distinguished by the absence of a mandibular molar (present in Liropus) and 2-articulate mandibular palp (3-articulate in Liropus). Pseudoprotella australiensis can be differentiated from all the remaining species of Pseudoprotella mainly on the basis of the unique body ornamentation (acute projection on the head, pereonites with abundant tiny tubercles scattered over the surface, and rows of lateral tubercles on the proximal end of pereonites 2–4). Further collections in deep ecosystems are mandatory to properly understand global amphipod diversity in Australian waters.Ministerio de Ciencia, Innovación y Universidades de España. Programa “Salvador Madariaga

Global cooling as a driver of diversification in a major marine clade

Climate is a strong driver of global diversity and will become increasingly important as human influences drive temperature changes at unprecedented rates. Here we investigate diversification and speciation trends within a diverse group of aquatic crustaceans, the Anomura. We use a phylogenetic framework to demonstrate that speciation rate is correlated with global cooling across the entire tree, in contrast to previous studies. Additionally, we find that marine clades continue to show evidence of increased speciation rates with cooler global temperatures, while the single freshwater clade shows the opposite trend with speciation rates positively correlated to global warming. Our findings suggest that both global cooling and warming lead to diversification and that habitat plays a role in the responses of species to climate change. These results have important implications for our understanding of how extant biota respond to ongoing climate change and are of particular importance for conservation planning of marine ecosystems

Gnathophyllum taylori, a new species of caridean shrimp from south-eastern Australia (Crustacea: Decapoda: Gnathophyllidae)

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The candidate antimalarial drug MMV665909 causes oxygen-dependent mRNA mistranslation and synergises with quinoline-derived antimalarials

To cope with growing resistance to current antimalarials, new drugs with novel modes of action are urgently needed. Molecules targeting protein synthesis appear to be promising candidates. We identified a compound (MMV665909) from the MMV Malaria Box of candidate antimalarials that could produce synergistic growth inhibition with the aminoglycoside antibiotic paromomycin, suggesting a possible action of the compound in mRNA mistranslation. This mechanism of action was substantiated with the yeast cell model using available reporters of mistranslation and other genetic tools. Mistranslation induced by MMV665909 was oxygen-dependent, suggesting a role for reactive oxygen species (ROS). Overexpression of Rli1 (a ROS-sensitive, conserved FeS protein essential in mRNA translation) rescued inhibition by MMV665909, consistent with the drug’s action on translation fidelity being mediated through Rli1. The MMV drug also synergised with major quinoline-derived antimalarials which can perturb amino acid availability or promote ROS stress: chloroquine, amodiaquine and primaquine. The data collectively suggest translation-fidelity as a novel target of antimalarial action and support MMV665909 as a promising drug candidate