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Figure 1 in Relationships of the haematophagous marine snail Colubraria (Rachiglossa: Colubrariidae), within the neogastropod phylogenetic framework
No full textFigure 1. Colubraria muricata (Lightfoot, 1786), the type species of the genus. A, Colubraria muricata feeding on a Siganus sp. at Santo Island (Palliculo Bay; depth, 11 m; photo S. Schiaparelli). B, the cephalic region of C. muricata from Santo Island. C, shells of C. muricata from the Philippines (photo G. & P. Poppe).Published as part of Oliverio, Marco & Modica, Maria Vittoria, 2010, Relationships of the haematophagous marine snail Colubraria (Rachiglossa: Colubrariidae), within the neogastropod phylogenetic framework, pp. 779-800 in Zoological Journal of the Linnean Society 158 (4) on page 780, DOI: 10.1111/j.1096-3642.2009.00568.x, http://zenodo.org/record/543845
Relationships of the haematophagous marine snail Colubraria (Rachiglossa: Colubrariidae), within the neogastropod phylogenetic framework
No full textThe gastropod genus Colubraria includes marine shallow-water species from tropical, subtropical, and temperate rocky coral environments. At least six species are known to feed on fish blood. Although there is general consensus in placing Colubraria in the Neogastropoda, the actual relationships and the systematic position of Colubraria and related genera are unknown. This is partly the consequence of the lack of a clear phylogenetic framework for the Neogastropoda. This study attempts to propose a phylogenetic framework for the Neogastropoda, by testing: (1) a preliminary phylogenetic arrangement for a large number of recognized neogastropod families; (2) the position of Colubraria within the neogastropods; and (3) the relationships of Colubraria within one of the major neogastropod lineages. We used two different molecular data sets. The first set included representatives of at least 14 neogastropod families, for points (1) and (2), and was based on mitochondrial (16S, 12S, and cytochrome oxidase subunit I, COI) and nuclear (28S) DNA sequences, giving a total of 3443 aligned positions. The second data set, for point (3), included 30 buccinoid sequences from mitochondrial 16S, giving a total of 1029 aligned positions. We also studied the anatomy of the type species of Colubraria and compared it with other neogastropods within the new phylogenetic framework. The results included the first phylogeny of the neogastropod based on 50% of the recognized families. This clearly indicated that the nematoglossan Cancellariidae represent a basal offshoot of the monophyletic Neogastropoda, and that the toxoglossan Conoidea are the sister group to the Rachiglossa. Within the Rachiglossa, a colubrariid clade, worthy of family ranking, showed clear buccinoid affinities. Most of the anatomy of Colubraria is congruent with a buccinoid model. The peculiar anatomical features that do not conform to the buccinoid model seem to be related to the evolution of haematophagous feeding
Neither slugs nor snails: a molecular reappraisal of the gastropod family Velutinidae
Full text linkFassio, Giulia, Stefani, Matteo, Russini, Valeria, Buge, Barbara, Bouchet, Philippe, Treneman, Nancy, Malaquias, Manuel António E., Schiaparelli, Stefano, Modica, Maria Vittoria, Oliverio, Marco (2023): Neither slugs nor snails: a molecular reappraisal of the gastropod family Velutinidae. Zoological Journal of the Linnean Society 197 (4): 924-964, DOI: 10.1093/zoolinnean/zlac091, URL: http://dx.doi.org/10.1093/zoolinnean/zlac09
The Neogastropoda: Evolutionary Innovations of Predatory Marine Snails with Remarkable Pharmacological Potential
No full textThe Neogastropoda include many familiar molluscs, such as cone snails (Conidae), purple dye snails (Muricidae), mud snails (Nassariidae), olive snails (Olividae), oyster drills (Muricidae), tulip shells (Fasciolariidae), and whelks (Buccinidae). Due to their amazing predatory specializations, neogastropods are often dominant members of the benthic community at the top of the food chain. In a dazzling display that ranges from boring holes to darting harpoons, neogastropods have developed several prey hunting innovations with specialized compounds pharmaceutical companies could only dream about. It has been hypothesized that evolutionary innovations related to feeding were the main drivers of the rapid neogastropod radiation in the late Cretaceous. The anatomical, behavioral, and biochemical specializations of neogastropod families that are promising targets in drug discovery and development are addressed within an evolutionary framework in this chapter
The anatomy and relationships of Troschelia (Neogastropoda: Buccinidae): New evidence for a closer fasciolariid-buccinid relationship?
No full textVolume: 123Start Page: 95End Page: 10
The coralliophiline (Gastropoda: Muricidae) radiation: repeated colonizations of the deep sea?
No full textThe relationships of the enigmatic gastropod Tritonoharpa (Neogastropoda): New data on early neogastropod evolution?
Full text linkVolume: 123Start Page: 177End Page: 18
DNA-barcoding of sympatric species of ectoparasitic gastropods of the genus Cerithiopsis (Mollusca: Gastropoda: Cerithiopsidae) from Croatia
No full textThe ectoparasitic gastropod genus Cerithiopsis Forbes & Hanley, 1850 was nominally based on Murex tubercularis Montagu, 1803. We have used the DNA barcode COI sequences to assay sympatric samples of morphotypes recently described as distinct species of the Cerithiopsis tubercularis-complex. Our results demonstrated that, in the Croatian waters, the gastropods usually called C. tubercularis in fact comprise a complex of cryptic species, which can be reliably diagnosed only by examining the soft parts. In the present study we have demonstrated that the colour pattern of the head-foot is diagnostic at the species level in this complex and, coupled with genetic data, may provide a sounding base for a revision of the cerithiopsids of the European coasts. Copyright © Marine Biological Association of the United Kingdom 2012
Larval strategies and connectivity in marine gastropods
No full textConnectivity is defined as the property and degree of interchange between populations. In the marine environment, this property is strongly influenced by the strategy of larval development. This is especially true for benthic organisms, which have a sessile adult lifestyle and can rely only on the larval phase for dispersal. Larval developments can be classified into two main types: planktotrophic and non-planktotrophic (mostly lecithothrophic) development. It is reasonable to hypothesize that different larval developments produce different patterns of connectivity. Several hypotheses can be tested on the relationship between genetic connectivity and duration of the larval phase: (i) isolation by distance occurs in species with non- planktotrophic development and not in species with planktotrophic development; (ii) genetic diversity and variance distribution are different in the two classes: low diversity and larger intrapopulation variance with planktotrophic development; high diversity and larger interpopulation variance with lecithothrophic development; (iii) different phylogeographic structure: phylogenetic trees not geographically structured with planktotrophic development and geographically structured with lecithothrophic development; (iv) different haplotypes networks: few haplotypes shared by most with planktotrophic development, and more haplotypes shared by geographically related groups with the lecithothrophic development. We first positively tested these hypotheses on literature datasets of three species of the genus Crepidula with different larval developments. Then we applied the same approaches on three original case studies: the sibling species Columbella rustica (Mediterranean, lecithotrophic) and C. adansoni (Atlantic, planktotrophic); and the Antarctic Capulus subcompressus and Marseniopsis spp. (both planktotrophic). All analyses positively tested the hypotheses of relationship between genetic connectivity and duration of the larval phase. Noteworthy, in Antarctica the planktotrophic development is usually severely counterselected, due the strictly seasonal presence of phytoplankton. Capulus subcompressus is the only Antarctic capulid with a planktotrophic development, and the genetics analyses confirmed the high connectivity patterns among populations as well as for species of the genus Marseniopsis
The venomous cocktail of the vampire snail Colubraria reticulata (Mollusca, Gastropoda)
Full text linkBackground: Hematophagy arose independently multiple times during metazoan evolution, with several lineages of vampire animals particularly diversified in invertebrates. However, the biochemistry of hematophagy has been studied in a few species of direct medical interest and is still underdeveloped in most invertebrates, as in general is the study of venom toxins. In cone snails, leeches, arthropods and snakes, the strong target specificity of venom toxins uniquely aligns them to industrial and academic pursuits (pharmacological applications, pest control etc.) and provides a biochemical tool for studying biological activities including cell signalling and immunological response. Neogastropod snails (cones, oyster drills etc.) are carnivorous and include active predators, scavengers, grazers on sessile invertebrates and hematophagous parasites; most of them use venoms to efficiently feed. It has been hypothesized that trophic innovations were the main drivers of rapid radiation of Neogastropoda in the late Cretaceous. We present here the first molecular characterization of the alimentary secretion of a non-conoidean neogastropod, Colubraria reticulata. Colubrariids successfully feed on the blood of fishes, throughout the secretion into the host of a complex mixture of anaesthetics and anticoagulants. We used a NGS RNA-Seq approach, integrated with differential expression analyses and custom searches for putative secreted feeding-related proteins, to describe in detail the salivary and mid-oesophageal transcriptomes of this Mediterranean vampire snail, with functional and evolutionary insights on major families of bioactive molecules. Results: A remarkably low level of overlap was observed between the gene expression in the two target tissues, which also contained a high percentage of putatively secreted proteins when compared to the whole body. At least 12 families of feeding-related proteins were identified, including: 1) anaesthetics, such as ShK Toxin-containing proteins and turripeptides (ion-channel blockers), Cysteine-rich secretory proteins (CRISPs), Adenosine Deaminase (ADA); 2) inhibitors of primary haemostasis, such as novel vWFA domain-containing proteins, the Ectonucleotide pyrophosphatase/phosphodiesterase family member 5 (ENPP5) and the wasp Antigen-5; 3) anticoagulants, such as TFPI-like multiple Kunitz-type protease inhibitors, Peptidases S1 (PS1), CAP/ShKT domain-containing proteins, Astacin metalloproteases and Astacin/ShKT domain-containing proteins; 4) additional proteins, such the Angiotensin-Converting Enzyme (ACE: vasopressive) and the cytolytic Porins. Conclusions:Colubraria feeding physiology seems to involve inhibitors of both primary and secondary haemostasis, anaesthetics, a vasoconstrictive enzyme to reduce feeding time and tissue-degrading proteins such as Porins and Astacins. The complexity of Colubraria venomous cocktail and the divergence from the arsenal of the few neogastropods studied to date (mostly conoideans) suggest that biochemical diversification of neogastropods might be largely underestimated and worth of extensive investigation. © 2015 Modica et al.}
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