Genetic connectivity of two marine gastropods in the Mediterranean Sea: seascape genetics reveals species-specific oceanographic drivers of gene flow.

Oceanographic features such as currents, waves, temperature and salinity, together with life history traits, control patterns and rates of gene flow and contribute to shaping the population genetic structure of marine organisms. Seascape genetics is an emerging discipline that adopts a spatially explicit approach to examine biotic and abiotic factors that drive gene flow in marine environments. In this study, we examined factors that contribute to genetic differentiation in two coastal Mediterranean gastropods whose geographical ranges overlap but which inhabit different environments. The two species differ in several life history traits and in their dispersal capabilities. Genetic differentiation was relatively low for the trochid species Gibbula divaricata (FST  =0.059), and high for the vermetid species Dendropoma lebeche (FST  =0.410). Salinity emerged as the most important variable explaining the genetic structure of both species; sea surface temperature was also important for G. divaricata. For the more sessile D. lebeche, the coastline was predicted to provide important pathways for stepping-stone connectivity and gene flow. Our results provide a greater understanding of the factors influencing marine population connectivity, which may be useful to guide marine conservation and management in the Mediterranean.

Asexual reproduction in bad times? The case of Cladocora caespitosa in the eastern Mediterranean Sea.

We analysed the patterns of genetic variability of eastern Mediterranean populations of the scleractinian coral Cladocora caespitosa, from the Aegean and Levantine seas, using 19 polymorphic microsatellite loci, 11 of which were newly characterized. The observed genetic pattern reflects a scenario of isolation by environment: F ST comparisons showed a higher degree of genetic differentiation between the two Cypriot populations that are separated by only 11 km than between these two Levantine populations and the Aegean population in Greece, which are separated by 1300 km. We hypothesize that local-scale oceanographic factors influenced the dispersal of planulae between the geographically close populations, playing a crucial role in the genetic structure of this coastal coral. Yet, despite being characterized as a species with limited dispersal and high self-recruitment, large-scale migration does eventually occur as first-generation migrants were identified between the most distant populations. In line with previous findings of reproductive plasticity in C. caespitosa, we also found localized differences in reproduction mode (sexual vs. asexual) within a geographically limited context. Several individuals were identified as clones, indicating the predominance of asexual reproduction in one of the Cypriot populations. We interpret this predominance either as a direct response to or as an indirect consequence of perturbations suffered by this C. caespitosa population. These perturbations are caused by unfavourable environmental conditions that threatened local survival, in particular water temperature changes and windstorm swells. Asexual reproduction may be a mechanism used by C. caespitosa to counteract mortality events and recolonize devastated areas, and likely accounts for the occasional high levels of clonality and low levels of genetic diversity. Local adaptations such as these should therefore be considered in conservation and management strategies to maintain and preserve the gene pool of this endangered species. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at (10.1007/s00338-020-02040-3).

Isolation of microsatellite loci for the endangered vermetid gastropod Dendropoma lebeche using Illumina MiSeq next generation sequencing technology.

Dendropoma petraeum, considered the primary vermetid reef-building species in the Mediterranean, has recently been shown to be a species complex of at least four cryptic species. These species have highly restricted, non-overlapping distributions, causing concern for their conservation status. To better study the genetic diversity of these populations, we selected one of these species, Dendropoma lebeche (Templado et al. in Mediterr Mar Sci 17(1):13-31, 2016), which is restricted to the western Mediterranean, for microsatellite marker development using Illumina MiSeq. We provide an initial survey of 29 polymorphic microsatellite loci for D. lebeche. Genetic analyses identified 2-11 alleles per locus across the 30 samples examined. Observed and expected heterozygosities ranged from 0.067 to 0.800 and 0.064 to 0.770, respectively. None of the loci deviated from Hardy-Weinberg equilibrium or showed signs of being under selective pressure. Significant linkage disequilibrium was found between two loci. We also show the cross-species amplification of these microsatellite markers in the other three species of the complex, the Tyrrhenian-Sicilian lineage, D. cristatum (Biondi, 1859), the Levantine lineage, D. anguliferum (Monterosato, 1878) and Dendropoma sp. found along the Ionian-Aegean coasts, suggesting their potential utility for future phylogenetic and evolutionary studies.

Merging scleractinian genera: the overwhelming genetic similarity between solitary Desmophyllum and colonial Lophelia.

BACKGROUND: In recent years, several types of molecular markers and new microscale skeletal characters have shown potential as powerful tools for phylogenetic reconstructions and higher-level taxonomy of scleractinian corals. Nonetheless, discrimination of closely related taxa is still highly controversial in scleractinian coral research. Here we used newly sequenced complete mitochondrial genomes and 30 microsatellites to define the genetic divergence between two closely related azooxanthellate taxa of the family Caryophylliidae: solitary Desmophyllum dianthus and colonial Lophelia pertusa. RESULTS: In the mitochondrial control region, an astonishing 99.8 % of nucleotides between L. pertusa and D. dianthus were identical. Variability of the mitochondrial genomes of the two species is represented by only 12 non-synonymous out of 19 total nucleotide substitutions. Microsatellite sequence (37 loci) analysis of L. pertusa and D. dianthus showed genetic similarity is about 97 %. Our results also indicated that L. pertusa and D. dianthus show high skeletal plasticity in corallum shape and similarity in skeletal ontogeny, micromorphological (septal and wall granulations) and microstructural characters (arrangement of rapid accretion deposits, thickening deposits). CONCLUSIONS: Molecularly and morphologically, the solitary Desmophyllum and the dendroid Lophelia appear to be significantly more similar to each other than other unambiguous coral genera analysed to date. This consequently leads to ascribe both taxa under the generic name Desmophyllum (priority by date of publication). Findings of this study demonstrate that coloniality may not be a robust taxonomic character in scleractinian corals.

Surviving the Messinian Salinity Crisis? Divergence patterns in the genus Dendropoma (Gastropoda: Vermetidae) in the Mediterranean Sea.

Four genetically distinct clades were recently described under the name Dendropoma petraeum, a Mediterranean endemic vermetid gastropod. The aim of this work is to date the processes that drove to the diversification within this taxon and to relate them to the corresponding historical events occurred in the Mediterranean Sea. Sequences from mitochondrial and nuclear markers were obtained from specimens collected in 29 localities spanning over 4000km across the entire distribution range of D. petraeum species complex. The phylogenetic and coalescent-based analyses confirmed the four well-supported and largely differentiated lineages of D. petraeum, clearly delimited geographically along a west-east axis within the Mediterranean Sea: Western, Tyrrhenian-Sicilian, Ionian-Aegean and Levantine lineages. Divergence time estimates, obtained using a range of known substitution rates for other marine gastropods, indicated two main stages of diversification. In the first period (between 9.5 and 4.5mya), the ancestral D. petraeum diverged into the current four lineages. The most recent period occurred between 3.72 and 0.66mya in the late Pliocene-early Pleistocene, and included the main within-lineage diversification events. Therefore, if the divergence time between the major lineages of Dendropoma in the Mediterranean actually predated or coincided with the Messinian Salinity Crisis, then they should have survived to this dramatic period within the Mediterranean, as supported by Bayes Factors model comparison. Conversely, if the divergence started after the crisis, congruent with the idea that no true marine organism survived the Messinian Salinity Crisis, then our results indicate substitution rates of Dendropoma much higher than usual (5.16% per million years for COI, 3.04% for 16S). More recent climate changes seem to have conditioned the demographic history of each lineage differently. While Western and Tyrrhenian-Sicilian lineages both underwent an increase in their effective population sizes from 1.5 to 0.6mya coinciding with a long interglacial period, the Ionian-Aegean and Levantine lineages showed constant effective population sizes since 2-2.5mya, suggesting that these eastern lineages might represent small and relict populations surviving the subsequent Quaternary glaciations in isolated refugia.

Carinina ochracea (Palaeonemertea: Tubulanidae) Reaches Its Southernmost Distribution: New Morphological and Molecular Data.

New data for Carinina ochracea Sundberg et al., 2009 are provided for the Iberian Peninsula, establishing the southernmost limit of its known distribution. This species was previously known from only two localities: the type locality in Tjärnö (Sweden) and Pouldohan (Brittany, France). The material examined here was obtained during a faunal survey in the Villaviciosa Estuary (Asturias, northern Iberian Peninsula). The identity of the new specimen was confirmed both by DNA barcoding and anatomical examination. The molecular divergence of all available sequences of this species for four molecular markers, cytochrome c oxidase subunit I (COI), 16S, 18S and 28S rDNA, is discussed. For COI, four polymorphic sites were found, indicating: 1) a nuclear pseudogene; 2) heteroplasmy; or 3) gene duplication of a region of the mitochondrial genome. Two previously overlooked morphological characters were found: the presence of a colour ring and a postfixation staining band (pigmented band), which is histologically characterized. This species is the 12th palaeonemertean and the 75th nemertean reported from Iberian waters.

Malacobdella arrokeana: Parasite or Commensal of the Giant Clam Panopea abbreviata?

We examined trophic relationship between the nemertean Malacobdella arrokeana and its host, the edible geoduck Panopea abbreviata by studying the diets of both species by direct (stomach contents) and indirect methods (stable-isotope analysis of C and N). In addition to these methods, the feeding behavior of M. arrokeana within the host and the morphology of its feeding organs were examined. The feeding behavior of M. arrokeana did not exhibit parasitic characteristics, and the proboscis morphology indicates it is unable to injure host tissues. Analysis of stomach contents revealed a diet consisting mainly of microalgae and diatoms. Panopea abbreviata and M. arrokeana shared similar trophic levels, presenting no differences in the spread of the isotopic niches and high overlap (SEAB overlapped 63%). Consistent with this, our results showed no differences in δ(15)N or δ(13)C values between the two species. The combination of direct and indirect approaches revealed that M. arrokeana has a diet similar to that of its host, confirming a commensal relationship.

Species Diversity of Ramphogordius sanguineus/Lineus ruber-Like Nemerteans (Nemertea: Heteronemertea) and Geographic Distribution of R. sanguineus.

Heteronemerteans, such as Lineus ruber, L. viridis, Ramphogordius sanguineus, R. lacteus, Riseriellus occultus, and Micrura varicolor, share many similar external characters. Although several internal characters useful for distinguishing these nemertean species have been documented, their identification is based mostly on coloration, the shape of the head, and how they contract, which may not be always reliable. We sequenced the mitochondrial COI gene for 160 specimens recently collected from 27 locations around the world (provisionally identified as the above species, according to external characters and contraction patterns, with most of them as R. sanguineus). Based on these specimens, together with sequences of 16 specimens from GenBank, we conducted a DNA-based species delimitation/identification by means of statistical parsimony and phylogenetic analyses. Our results show that the analyzed specimens may contain nine species, which can be separated by large genetic gaps; heteronemerteans with an external appearance similar to R. sanguineus/Lineus ruber/L. viridis have high species diversity in European waters from where eight species can be discriminated. Our 42 individuals from Vancouver Island (Canada) are revealed to be R. sanguineus, which supports an earlier argument that nemerteans reported as L. ruber or L. viridis from the Pacific Northwest may refer to this species. We report R. sanguineus from Chile, southern China, and the species is also distributed on the Atlantic coast of South America (Argentina). In addition, present analyses reveal the occurrence of L. viridis in Qingdao, which is the first record of the species from Chinese waters.

Development of Microsatellite Markers in the Deep-Sea Cup Coral Desmophyllum dianthus by 454 Sequencing and Cross-Species Amplifications in Scleractinia Order.

Microsatellite loci were isolated for the first time for the deep-sea coral Desmophyllum dianthus, using 454 GS-FLX Titanium pyrosequencing. We developed conditions for amplifying 24 markers in 10 multiplex reactions. Three to 16 alleles per locus were detected across 25 samples analyzed from Santa Maria di Leuca coral province (Mediterranean Sea). For the 24 polymorphic loci, observed and expected heterozygosities ranged from 0.211 to 0.880 and 0.383 to 0.910, respectively; 3 loci deviated from Hardy-Weinberg equilibrium, after null allele and sequential Holm-Bonferroni corrections. These newly isolated microsatellites are very useful genetic markers that provide data for future conservation strategies. Cross-amplification of these microsatellites, tested in 46 coral species, representing 40 genera, and 10 families of the phylum Cnidaria, produced informative allelic profiles for 1 to 24 loci. The utility of extending analyses to cross-species amplifications is also discussed.

DNA barcoding and morphology revealed the existence of seven new species of squat lobsters in the family Munididae (Decapoda, Galatheoidea) in the southwestern Pacific.

Specimens of squat lobsters belonging to the family MunididaeAhyong et al., 2010, representing the genera Garymunida Macpherson & Baba, 2022, Trapezionida Macpherson & Baba, 2022 and Typhlonida Macpherson & Baba, 2022, were collected during several cruises around New Caledonia and Papua New Guinea, Southwest Pacific. The integrative study of these specimens revealed the presence of one new species in Garymunida, five in Trapezionida and one in Typhlonida. We describe and illustrate these new species, providing some new data on the taxonomy of several rare or scarcely studied species of Trapezionida. Molecular data from different markers (mitochondrial and nuclear) was also included, based on data availability, to support the taxonomic status of different species. Finally, a key to species for each genus is also provided.

Unravelling the relationships among Madrepora Linnaeus, 1758, Oculina Lamark, 1816 and Cladocora Ehrenberg, 1834 (Cnidaria: Anthozoa: Scleractinia).

Despite the widespread use of integrative taxonomic approaches, many scleractinian coral genera and species remain grouped in polyphyletic families, classified as incertae sedis or simply understudied. Oculinidae Gray, 1847 represents a family for which many taxonomic questions remain unresolved, particularly those related to some of the current genera, such as Oculina Lamark, 1816 or recently removed genera, including Cladocora Ehrenberg, 1834 and Madrepora Linnaeus, 1758. Cladocora is currently assigned to the family Cladocoridae Milne Edwards & Haime, 1857 and a new family, Bathyporidae Kitahara, Capel, Zilberberg & Cairns, 2024, was recently raised to accommodate Madrepora . However, the name Bathyporidae is not valid because this was not formed on the basis of a type genus name. To resolve taxonomic questions related to these three genera, the evolutionary relationships are explored through phylogenetic analyses of 18 molecular markers. The results of these analyses support a close relationship between the species Oculina patagonica and Cladocora caespitosa , indicating that these may belong to the same family (and possibly genus), and highlighting the need for detailed revisions of Oculina and Cladocora . By contrast, a distant relationship is found between these two species and Madrepora oculata , with the overall evidence supporting the placement of Madrepora in the resurrected family Madreporidae Ehrenberg, 1834. This study advances our knowledge of coral systematics and highlights the need for a comprehensive review of the genera Oculina , Cladocora and Madrepora .

Living on the mountains: patterns and causes of diversification in the springsnail subgenus Pseudamnicola (Corrosella) (Mollusca: Caenogastropoda: Hydrobiidae).

Hydrobiidae is one of the largest families of freshwater gastropods comprised of approximately 400 genera and 1000 species. Despite this high level of diversity, most hydrobiid species inhabit fragile ecosystems in restricted distribution areas. In this work, we analyze modes of speciation and causes of diversification in the hydrobiid springsnail subgenus Pseudamnicola (Corrosella). Species of this group typically live in nutrient poor springs and streams and are restricted to mountainous regions of the Iberian Peninsula (Spain) and Southern France. Previous morphological and molecular (based only on the cytochrome c oxidase subunit I (COI) gene) studies revealed 11 nominal Corrosella species. In this study, we enhance published molecular results by generating new data from mitochondrial (16S rRNA and COI) and nuclear ribosomal regions (18S and 28S rRNA) from 50 Corrosella populations. As a result of this study we have identified one new species, making a total of twelve recognized species in the subgenus Corrosella. Our phylogenetic results also reveal the existence of three lineages within the subgenus, and the estimation of time divergence indicates the occurrence of three main speciation events during the upper Miocene to Pleistocene. We test the influence of several geographical and ecological variables and observe that diversification patterns are related to habitat fragmentation rather than environmental conditions. This result suggests that the high level of diversity observed within the subgenus may have resulted from a non-adaptive radiation. The formation of the Iberian Peninsula mountain ranges (the Pyrenees in the north and the Betic Cordillera in the south) and the configuration of the Iberian current hydrographic system played important roles in Corrosella speciation. Additionally, during the Miocene the Iberian Peninsula experienced a gradient of increasing temperature and dryness from north to south, which together with a high level of tectonic activity, may have caused the majority of the diversity found in the southern Iberian Peninsula.

On the conservation of white-clawed crayfish in the Iberian Peninsula: Unraveling its genetic diversity and structure, and origin.

European crayfish species are a clear example of the drastic decline that freshwater species are experiencing. In particular, the native species of the Iberian Peninsula, the white clawed-crayfish (WCC) Austropotamobius pallipes, is listed as "endangered" by the IUCN and included in Annex II of the EU Habitat Directive and requires especially attention. Currently, implemented conservation management strategies require a better understanding of the genetic diversity and phylogeographic patterns, as well as of its evolutionary history. For this purpose, we have generated the largest datasets of two informative ribosomal mitochondrial DNA regions, i.e., cytochrome oxidase subunit I and 16S, from selected populations of the WCC covering its geographical distribution. These datasets allowed us to analyze in detail the (i) genetic diversity and structure of WCC populations, and (ii) divergence times for Iberian populations by testing three evolutionary scenarios with different mtDNA substitution rates (low, intermediate, and high rates). The results indicate high levels of haplotype diversity and a complex geographical structure for WCC in the Iberian Peninsula. The diversity found includes new unique haplotypes from the Iberian Peninsula and reveals that most of the WCC genetic variability is concentrated in the northern and central-eastern regions. Despite the fact that molecular dating analyses provided divergence times that were not statistically supported, the proposed scenarios were congruent with previous studies, which related the origin of these populations with paleogeographic events during the Pleistocene, which suggests an Iberian origin for these WCC. All results generated in this study, indicate that the alternative hypothesis of an introduced origin of the Iberian WCC is highly improbable. The result of this study, therefore, has allowed us to better understand of the genetic diversity, structure patterns, and evolutionary history of the WCC in the Iberian Peninsula, which is crucial for the management and conservation needs of this endangered species.

A horizon scan exercise for aquatic invasive alien species in Iberian inland waters.

As the number of introduced species keeps increasing unabatedly, identifying and prioritising current and potential Invasive Alien Species (IAS) has become essential to manage them. Horizon Scanning (HS), defined as an exploration of potential threats, is considered a fundamental component of IAS management. By combining scientific knowledge on taxa with expert opinion, we identified the most relevant aquatic IAS in the Iberian Peninsula, i.e., those with the greatest geographic extent (or probability of introduction), severe ecological, economic and human health impacts, greatest difficulty and acceptability of management. We highlighted the 126 most relevant IAS already present in Iberian inland waters (i.e., Concern list) and 89 with a high probability of being introduced in the near future (i.e., Alert list), of which 24 and 10 IAS, respectively, were considered as a management priority after receiving the highest scores in the expert assessment (i.e., top-ranked IAS). In both lists, aquatic IAS belonging to the four thematic groups (plants, freshwater invertebrates, estuarine invertebrates, and vertebrates) were identified as having been introduced through various pathways from different regions of the world and classified according to their main functional feeding groups. Also, the latest update of the list of IAS of Union concern pursuant to Regulation (EU) No 1143/2014 includes only 12 top-ranked IAS identified for the Iberian Peninsula, while the national lists incorporate the vast majority of them. This fact underlines the great importance of taxa prioritisation exercises at biogeographical scales as a step prior to risk analyses and their inclusion in national lists. This HS provides a robust assessment and a cost-effective strategy for decision-makers and stakeholders to prioritise the use of limited resources for IAS prevention and management. Although applied at a transnational level in a European biodiversity hotspot, this approach is designed for potential application at any geographical or administrative scale, including the continental one.

Genetic Structure of the Endangered Coral Cladocora caespitosa Matches the Main Bioregions of the Mediterranean Sea.

Population connectivity studies are a useful tool for species management and conservation planning, particular of highly threatened or endangered species. Here, we evaluated the genetic structure and connectivity pattern of the endangered coral Cladocora caespitosa across its entire distribution range in the Mediterranean Sea. Additionally, we examined the relative importance of sexual and asexual reproduction in the studied populations and their genetic diversity. A total of 541 individuals from 20 localities were sampled and analysed with 19 polymorphic microsatellite markers. Of the genotyped individuals, 482 (89%) had unique multilocus genotypes. Clonality percentages of the populations varied from 0% (in eight populations) to nearly 69% (in one population from Crete). A heterozygosity deficit and a high degree of inbreeding was the general trend in our data set. Population differentiation in C. caespitosa was characterised by significant pairwise F ST values with lower ones observed at an intraregional scale and higher ones, between populations from different biogeographic regions. Genetic structure analyses showed that the populations are divided according to the three main sub-basins of the Mediterranean Sea: the Western (Balearic, Ligurian and Tyrrhenian seas), the Central (Adriatic and Ionian seas) and the Eastern (Levantine and Aegean seas), coinciding with previously described gene flow barriers. However, the three easternmost populations were also clearly separated from one another, and a substructure was observed for the other studied areas. An isolation-by-distance pattern was found among, but not within, the three main population groups. This substructure is mediated mainly by dispersal along the coastline and some resistance to larval movement through the open sea. Despite the low dispersal ability and high self-recruitment rate of C. caespitosa, casual dispersive events between regions seem to be enough to maintain the species' considerable genetic diversity. Understanding the population connectivity and structure of this endangered scleractinian coral allows for more informed conservation decision making.

House sparrows do not exhibit a preference for the scent of potential partners with different MHC-I diversity and genetic distances.

MHC genes play a fundamental role in immune recognition of pathogens and parasites. Therefore, females may increase offspring heterozygosity and genetic diversity by selecting males with genetically compatible or heterozygous MHC. In birds, several studies suggest that MHC genes play a role in mate choice, and recent evidence suggests that olfaction may play a role in the MHC-II discrimination. However, whether olfaction is involved in MHC-I discrimination in birds remains unknown. Previous studies indicate that house sparrow females with low allelic diversity prefer males with higher diversity in MHC-I alleles. Here, we directly explored whether female and male house sparrows (Passer domesticus) could estimate by scent MHC-I diversity and/or dissimilarity of potential partners. Our results show that neither females nor males exhibit a preference related to MHC-I diversity or dissimilarity of potential partners, suggesting that MHC-I is not detected through olfaction. Further studies are needed to understand the mechanisms responsible for mate discrimination based on MHC-I in birds.

The shrunk genetic diversity of coral populations in North-Central Patagonia calls for management and conservation plans for marine resources.

The Chilean Patagonia is a complex puzzle of numerous fjords, channels, bays, estuaries, and islands. The largest part of it is very remote, hampering the generation of scientific knowledge and effective management planning that could balance conservation of the marine resources with the increasing development of aquaculture activities. The present study focuses on the deep-water emergent cold-water coral Desmophyllum dianthus, dwelling in Chilean Patagonia, with the aim to illustrate its population genetic structure, demography and adaptation of the species along this coast. Microsatellite loci analysis included D. dianthus individuals from twelve sampling localities along bathymetric and oceanographic gradients from the latitude 40°S to 48°S. The results showed a lack of genetic structure with an asymmetric dispersion of individuals, and relevant heterozygosity deficiency in some populations. This study also analyses the natural and human impacts affecting the region (e.g., climate change, increasing salmon farming activities), and stresses the importance of including genetic information in the process of management and conservation of marine resources. In particular, the relevance of using interdisciplinary approaches to fill the gaps in scientific knowledge especially in remote and pristine areas of western Patagonia. Therefore, information on genetic spatial distribution of marine fauna could become pivotal to develop a holistic ecosystem-based approach for marine spatial planning.

Climate warming triggers the emergence of native viruses in Iberian amphibians.

The number of epizootics in amphibian populations caused by viruses of the genus Ranavirus is increasing worldwide. Yet, causes for pathogen emergence are poorly understood. Here, we confirmed that the Common midwife toad virus (CMTV) and Frog virus 3 (FV3) are responsible for mass mortalities in Iberia since the late 1980s. Our results illustrate the Iberian Peninsula as a diversity hotspot for the highly virulent CMTV. Although this pattern of diversity in Europe is consistent with spread by natural dispersal, the exact origin of the emergence of CMTV remains uncertain. Nevertheless, our data allow hypothesizing that the Iberian Peninsula might harbor the ancestral population of CMTVs that could have spread into the rest of Europe. In addition, we found that climate warming could be triggering the CMTV outbreaks, supporting its endemic status in the Iberian Peninsula.

Development of microsatellite markers as a molecular tool for conservation studies of the Mediterranean reef builder coral Cladocora caespitosa (Anthozoa, Scleractinia).

Cladocora caespitosa is a reef-building zooxanthellate scleractinian coral in the Mediterranean Sea. Mortality events have recurrently affected this species during the last decade. Thus, knowledge of its genetic structure, population diversity, and connectivity is needed to accomplish suitable conservation plans. In order to obtain a better understanding of the population genetics of this species, 13 highly variable microsatellites markers were developed from a naturally bleached colony. The developed primers failed to amplify zooxanthella DNA, isolated from C. caespitosa, verifying that these markers were of the coral and not algal symbiont origin. The degree of polymorphism of these loci was tested on tissue samples from 28 colonies. The allele number for each loci ranged from 2 to 13 (mean N(a) = 5.4), with an average observed heterozygosity of 0.42 (H(e) = 0.43) and all loci were in Hardy-Weinberg equilibrium. These new markers should be useful in future conservation genetic studies and will help to improve the resolution of the individual identification within this coral species. Primers were also tested in Oculina patagonica, with successful amplifications of several loci.

Revision of the squat lobsters of the genus Phylladiorhynchus Baba, 1969 (Crustacea, Decapoda, Galatheidae) with the description of 41 new species.

The genus Phylladiorhynchus Baba, 1969 currently contains 11 species, all occurring in the shallow waters and on the continental shelf of the Indian and Pacific oceans. Recent expeditions in these oceans have resulted in the collection of numerous new specimens in need of analysis. We have studied this material using an integrative approach analysing both morphological and molecular (COI and 16S) characters. We describe 41 new species and resurrect three old names: P. integrus (Benedict, 1902) and P. lenzi (Rathbun, 1907), previously synonymized with P. pusillus (Henderson, 1885), and P. serrirostris (Melin, 1939), previously synonymized with P. integrirostris (Dana, 1852). Most species of the genus are described and illustrated. Some species are barely discernible on the basis of morphological characters but are highly divergent genetically. Species of Phylladiorhynchus are mainly distinguishable by the number of epigastric spines and lateral spines of the carapace, the shape and the armature of the rostrum, the number and pattern of the ridges on the carapace and pleon, the shape of thoracic sternite 3 and the armature of the P24 dactyli. A dichotomous identification key to all species is provided.