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Panulirus argus (Latreille in Ann Mus Hist Nat Paris 3:388-395, 1804) is the lobster of greatest economic importance throughout its distribution. In this study, mitochondrial (Cytochrome Oxidase I and 16S ribosomal genes) and nuclear (Adenine Nucleotide Transporter gene) sequences were used to evaluate the taxonomic status of P. argus sampled from five sites in the Caribbean Sea and nine sites in the Southwest Atlantic. Phylogenetic analyses indicate that lobsters from the two regions form two monophyletic groups with a molecular divergence similar to that observed between distinct congeneric lobster species and much larger than that found between conspecific lobster populations. Therefore, the Caribbean and the Southwest Atlantic lobster populations originally attributed to P. argus belong to different species, with an estimated time of isolation of around 16 Million years. An important consequence of these findings is that the fisheries of spiny lobsters from the Caribbean and the Southwest Atlantic species must be managed separately., Introduction The spiny lobster P. argus (Latreille 1804) occurs from North Carolina (USA) to Rio de Janeiro (Brazil) and supports valuable fisheries throughout its distribution, where it is the lobster [...]

Marine sponges are an ecologically important and highly diverse component of marine benthic communities, found in all the world's oceans, at all depths. Although their commercial potential and evolutionary importance is increasingly recognized, many pivotal aspects of their basic biology remain enigmatic. Knowledge of historical biogeographic affinities and biodiversity patterns is rudimentary, and there are still few data about genetic variation among sponge populations and spatial patterns of this variation. Biodiversity analyses of tropical Australasian sponges revealed spatial trends not universally reflected in the distributions of other marine phyla within the Indo-West Pacific region. At smaller spatial scales sponges frequently form heterogeneous, spatially patchy assemblages, with some empirical evidence suggesting that environmental variables such as light and/or turbidity strongly contribute to local distributions. There are no apparent latitudinal diversity gradients at larger spatial scales but stochastic processes, such as changing current patterns, the presence or absence of major carbonate platforms and historical biogeography, may determine modern day distributions. Studies on Caribbean oceanic reefs have revealed similar patterns, only weakly correlated with environmental factors. However, several questions remain where molecular approaches promise great potential, e.g., concerning connectivity and biogeographic relationships. Studies to date have helped to reveal that sponge populations are genetically highly structured and that historical processes might play an important role in determining such structure. Increasingly sophisticated molecular tools are now being applied, with results contributing significantly to a better understanding of poriferan microevolutionary processes and molecular ecology.

Research has been conducted on the marine sponge Chondrosia reniformis. The analysis of the populations of this sponge from the western Mediterranean and the West Atlantic has been carried out via the use of allozyme electrophoresis for the enzyme loci and the results indicate that the gene identities between the populations of these locations are low.

The application of genetic techniques to invertebrate fisheries is in many ways essentially similar to that in vertebrate (i.e. finfish) fisheries, for which there is already an extensive body of published data. However, there are also relative differences which lead to particular problems in the use of genetic data to study commercially important invertebrate species. The main role for genetics of both vertebrates and invertebrates has been, and is likely to continue to be, the identification of groups of interbreeding individuals as the basis for a fishery. It is in the identification of the breeding unit that the genetic differences between vertebrates and invertebrates can be of practical significance. The genetic breeding unit, usually called a 'stock' in fisheries biology, generally shows a certain uniformity of size in most marine fish which have been studied. Smaller or less mobile fish (e.g. flatfish) may only range a few tens of kilometres to their breeding grounds, whilst in more mobile, particularly migratory pelagic species (e.g. Scombridae), the area occupied by a stock islikely to be far greater and for a few (e.g. large pelagic elasmobranchs), a single unit of stock may be almost circumglobal. However, marine fish generally, particularly those large or plentiful enough to be of commercial interest, are likely to be fairly mobile and in manycases the order of mobility is likely to be in the region we might predict from our knowledge of the biology and habits of the species. In the genetic assessment of 'stocks' for invertebrate fisheries, we face a number of additional problems, mostly related to the large evolutionary range of invertebrates exploited and their widely different biology. Although in Europe and North America marine invertebrate fisheries may be thought of as being mainly for decapod crustaceans and bivalve molluscs, globally commercially important marine invertebratefisheries range from sponges to squid and include such diverse groups a [ABSTRACT FROM AUTHOR]

Details the genetic confirmation of Triatoma petrochii species in Brazil. Similarity between T. petrochii and T. brasiliensis; Invasion on the domestic vector of Trypanosoma cruzi; Morphological differences between the Triatoma species.