In this study, we propose C. confusus, new species, an Andean slug of the genus Colosius Thomé, 1975, and a newly recognized pest of coffee and cultivated flowers from Colombia, Ecuador and Peru. We compare it with C. pulcher (Colosi, 1921), a poorly known species with which it has been confused. Our study is based on morphological analysis of a large number of specimens, including interceptions on cut-flowers and live plants by federal agricultural inspectors of the United States Department of Agriculture (USDA) and the Department of Homeland Security (DHS), and material from eight museum collections. Genetic diversity within C. confusus, n. sp. and C. pulcher is also analysed based on fragments of cytochrome oxidase I (COI), and 16S rRNA. They are differentiated by reproductive characters and genes studied. In C. confusus, n. sp., the phallus has a deep longitudinal groove from the base, near the retractor muscle, to its distal region, close to the papilla. In C. pulcher, there is an oval to rectangular swelling on the basal region of the phallus. Some important differences between these species are also found in the digitiform gland and bursa copulatrix. We describe, illustrate and discuss the color variation, morphological similarities, diagnostic characters and its variation, habitat and distribution for each species. Genetic diversity within C. confusus, n. sp., and C. pulcher is low. In order to analyze their relationship with C. propinquus (Colosi, 1921) (currently a junior synonym of C. pulcher) and C. lugubris (Colosi, 1921) (type-species of Colosius), fragments of COI, 16S, and 28S rRNA genes are also analyzed in a sample of these species. C. confusus, n. sp., is a distinct lineage within the genus Colosius. It is not a sister species of C. pulcher, which has C. propinquus as a sister species, here recognized as valid. Colosius confusus, n. sp., is closer to the clade that includes C. pulcher and C. propinquus than it is to C. lugubris. Based on the phylogenetic reconstruction, C. lugubris is sister to all the other Colosius, although additional studies are required to formally test phylogenetic placements and monophyly of the genus. Associated imports and number of interceptions per year of C. confusus, n. sp., by agricultural inspectors are also presented.

We studied changes of terrestrial snail assemblages over a gradient of soil moisture using 60 sampling plots in the White Carpathian Mountains of the south-eastern Czech Republic. We used within-site design to control for confounding effects of site characteristics other than humidity, and we directly measured soil moisture along nine transects at distinct locations. Each transect had from 4 to 16 plots, and it was laid down from wet calcium-rich spring fen habitats to semi-dry meadows in the fen surroundings. We observed a sharp moisture gradient along each transect, with the measured soil moisture varying from 97% in fen plots to 19% in semi-dry grassland plots. Altogether 29 land snail species and 4,213 live individuals were collected. Species richness of land snails varied from 2 to 11 species per plot. However, we did not observe any significant linear or unimodal response of species richness or total abundances to measured soil moisture. In contrast, sharp compositional changes along studied transects were found, suggesting differences in species preference to soil moisture conditions at fine, within-site scale. Among 21 species with the frequency higher than five, 10 (after a Bonferroni correction) showed a significant response to soil moisture. Three species expressed significant affinity to drier plots, five species were more abundant in moister plots and only two species preferred middle values. In several previous studies, both linear and hump-shaped relation between soil moisture and number of land snail species were documented. This raised questions about general response of land snails to soil moisture and the importance of possible bias caused either by using only estimated values of site moisture or sampling in distinct sites differing also in other environmental factors that might potentially overtopped importance of soil moisture for land snail distribution.

The invasive freshwater mussel, the mytilid Limnoperna fortunei (Dunker, 1857), has a great capacity for colonizing a wide range of aquatic environments because of its dispersal ability, high fecundity and wide range of physiological tolerances. Most of the biological and ecological studies of L. fortunei, having been restricted to specific locations, lack comparative analyses among different habitats. In this investigation, we examined the differences in larval density, density in settlement plates, shell allometry, and growth between two populations from the Rio de la Plata basin, Argentina. One of the populations inhabited a heavily polluted area, whereas the other a moderately polluted area. We predicted that the density and growth of the golden mussel would be lower in the heavily polluted environment, expecting therefore to find variations in shell allometry as a consequence of differences in density and environmental conditions between the sites investigated. We accordingly found that the larval density, the density of settled individuals, and the growth were lower in the more polluted environment. We also observed allometric differences because the individuals from the moderately polluted area with higher population densities were more elongated (i.e., with a higher shell length-to-width ratio). The golden mussel tolerates a wide range of environmental conditions and can survive in many polluted water bodies where other invasive species cannot. The findings presented here support the idea that L. fortunei can inhabit heavily polluted environments, but at the expense of a significant decrease in its biologic potential.

Intertidal communities from rocky shores of the southwestern Atlantic are dominated by two small-sized mussels of the genus Brachidontes, B. rodriguezii (d'Orbigny, 1846) and B. purpuratus (Lamarck, 1819). Their generic placement, separation of specimens based on external conchological characters and geographic distribution are problematic. We conducted a comparative study based on extensive collections and observations at 14 sites along the coasts of the southwestern Atlantic, complemented by the study of materials from museum collections. Well-preserved specimens of the two species are distinguishable on the basis of shell characters, some of them previously ignored, over their combined latitudinal range.

The reproductive biology of Eledone cirrhosa (Lamarck, 1798) was studied for the first time in the northern and eastern region of Tunisia. Monthly samples were provided from surveys carried out on board the Tunisian oceanographic vessel “Hannibal” and from commercial catches of bottom-trawl operating in this area from October 2005 to September 2006. Although specimens have been collected at a wide depth range, E. cirrhosa shows the greatest abundance between 100 and 300 m. The sex ratio was estimated at 0.94 with no significant difference (P > 0.05). Length-weight relationships calculated for each sex and the whole sample showed negative allometric growth (b < 3). The allometric coefficient in immature individuals revealed an allometric growth (b < 3) and isometric growth (b = 3) in maturing and mature individuals. A three-stage maturity scale was intended to distinguish between immature, maturing and fully mature animals. The reproductive season for females extended from April to August, with a spawning peak from June to August, and for males from January to August with a peak from April to August. The dorsal mantle length (DML) at maturity, corresponding to the size class when 50% of individuals were mature, was estimated at 6.88 cm in males, and 8.80 cm in females. The juveniles were mainly found in between 100 and 200 m where a nursery area for the species is probably present, while mature individuals were mostly fished at a depth greater than 200 m, which represents the spawning area of Eledone cirrhosa. Potential fecundity, estimated from 37 mature females, was 4171 ± 1216 oocytes. The number of spermatophores ranged from 42 to 121, with a mean length of 51.34 ± 4.86 mm.

Two species of geoduck clams, Panopea, are known from the Pacific coast of Mexico: P. generosa, also present in the temperate areas along the western coast of North America, and P. globosa, originally considered endemic to the Gulf of California. Often regarded as a temperate and a tropical species, their respective distributions were assumed to be clearly separate. However, commercial interests recently found populations in the temperate-tropical transition zone, thus raising doubts regarding their taxonomic identity and the distribution limits of each species. Discriminant function analysis was used to examine the morphological characteristics of the shells of individuals from nine locations to identify their species and to re-examine the distribution limits of Panopea spp. in this region. Results show that the tropical limit in the distribution of P. generosa is the western coast of the Baja California Peninsula, south to at least Punta Canoas (29°43′N). It was found that the distribution of P. globosa not only includes the Gulf of California but extends to at least Bahía Magdalena (24°38′N) on the western coast of the peninsula. This is the first report of P. globosa outside of the Gulf of California, thus extending its distribution to more temperate areas.

Microhabitat requirements of five vertiginid species — Vertigo angustior, V. moulinsiana, V. pygmaea, V. substriata and Columella edentula — were studied in two wetland areas of western Poland; two of the species, V. angustior and V. moulinsiana, are respectively listed as “near threatened” and “vulnerable” according to the IUCN red list. Data on the species and their habitats were collected biweekly during spring and summer months in 2008 and 2009 along four permanent transects at each site. Factors influencing the distribution of vertiginids were examined using Canonical Correspondence Analysis and Canonical Varieties Analysis. A variance partitioning approach was used to determine the influence of groups offactors.

The small-scale distribution of the vertiginids was strongly influenced by specific environmental conditions. Both abiotic microhabitat characteristics and vegetation structure significantly influenced the composition of the studied malacocenoses. The most important factors were: litter moisture, shading, ground water level and the abundance of the following plants species: Carex acutiformis, Thelypteris palustris, Lysimachia vulgaris and Urtica dioica. Within the habitats covered by the study, abiotic factors were more important than vegetation composition, although the influence of two groups of variables was partially overlapping.

The organic matrix proteins of molluscan nacre are known to engage biocompatible and osteoinductive properties. In this study, we aimed to extract Haliotis diversicolor nacreous proteins and assayed their effect on pre-osteoblastic cell differentiation. We found that acid extracted nacreous proteins (AEP) consisted primarily of a major protein band of 25 kDa and three other minor proteins. AEP enhanced alkaline phosphatase (ALP) activity of MC3T3-E1 cells both in time- and concentration-dependent manners. Transcriptional up-regulation of osteogenic markers, including collagen type I (COL-I), osteopontin (OPN) and osteocalcin (OCN), was also apparent in days 7 and 14 upon AEP treatments. At the translational level, higher protein expression of COL-I was evident in AEP treated cells, and the protein was presumably laid down as extracellular matrix. Further de novo sequencing of an AEP major protein revealed a match with the abalone mantle protein sometsuke. Conclusively, we demonstrated that H. diversicolor AEP contains a factor, potentially the mantle protein sometsuke, which may impart in the osteoblastic cell differentiation.

Commercially available radioimmunoassays (RIA) with ¹²⁵I-labeled hormones were adapted, developed and validated to quantify progesterone and testosterone in gonad extracts of Octopus maya, considered an easily domesticated species with potential in aquaculture. Development of the RIAs was divided into four phases: (1) extraction of progesterone and testosterone from gonads, (2) preparation of gonad extracts for RIA, (3) standards preparation, and (4) RIA procedure. Hormones were extracted twice with 15 mL of diethyl-ether each time. The recovered hormone and the solvent effect on extraction were evaluated. RIAs were validated based on specificity, sensitivity, accuracy, precision and reproducibility. Serially diluted gonad extracts were parallel to the standard curves of each hormone, indicating specificity. Sensitivities for both hormones were less than 0.1 ng·g^-1, and did not change by more than 20% during the ¹²⁵I half-life. Accuracy was 102.25 ± 11.22% for progesterone and 81.62 ± 6.24% for testosterone. For both hormones, precision was close to 13% and reproducibility 17%. The precision/reproducibility ratio indicated a system with good stability. The amounts of the hormones recovered increased when the number of extractions was increased. Hormone concentrations also increased when the volume of diethyl-ether used per extraction was increased. The range of progesterone and testosterone concentrations quantified in this study is in agreement with the range found in other octopuses. Finally, the developed and validated RIAs meet the requirements for quantification of progesterone and testosterone in Octopus gonad extracts and show that it is possible to use ¹²⁵I-labeled hormone as well as the plastic coated-tubes from commercial RIA kits to analyse variations in hormone levels associated with gonad developmental stages and the reproductive cycle of octopuses, allowing exploration of their possible functions.

We provide here a catalogue of all available species nomina of Orthalicoidea occurring in Argentina. Ongoing taxonomic revisions on the genera Bostryx Troschel, 1847, Clessinia Doering, 1874, Pilsbrylia Hylton Scott, 1952, and Spixia Pilsbry & Vanatta, 1898, highlighted the necessity of an updated catalogue for the region. A total of 101 orthalicoidean species classified into four families, Bothriembryontidae, Bulimulidae, Odontostomidae and Simpulopsidae are present in Argentina. The catalogue provided here is based on examination of primary literature, available revisions and monographs, comparative studies within and among species and revision of museum data, including most type specimens. Additional collection of specimens in various localities of the country was carried out for more than a decade to be able to accurately state distributional information on the species treated. Nomenclatural details are provided for all nominal species. Name-bearing types were located for 86 species-group taxa, and six lectotypes were designated for the stabilization of the taxonomy. We propose the following nine new combinations: Bulimulus fourmiersi (d'Orbigny, 1835), Clessinia cordovana (Pfeiffer, 1855), Drymaeus flossdorfi (Holmberg, 1909), Cyclodontina (Ventanía) avellanedae (Doering, 1881), Simpulopsis (Eudioptus) eudioptus (Ihering in Pilsbry, 1897), Spixia champaquiana (Doering, 1875), S. charpentieri(Grateloup in Pfeiffer, 1850), S. minor (d'Orbigny, 1837) and S. parodizi (Hylton Scott, 1951). The following four new synonymies are proposed: Bostryx sophieae Breure, 1979, with Bulimus cordillerae (Strobel, 1874) (current name Bostryx cordillerae); Cyclodontina (Clessinia) gracilis Hylton Scott, 1956, with Bulimus cordovanus Pfeiffer, 1855 (current name Clessinia cordovana); Spixia estherae Fernández, 1971, with Odontostomus (Spixia) costellifer Hass, 1936 (current name Spixia costellifer); Kuschelenia simulans Hylton Scott, 1951, with Helix tupacii d'Orbigny, 1835 (current name Scutalus tupacii). Bulimulus sporadicus gracilis Hylton Scott, 1948, is changed from subspecific to specific status.

Traces of predation by drilling gastropods and peeling crabs provide important insights about predator-prey interaction in ecological as well as evolutionary times. Predation on turritelline gastropods, in this context, has been frequently discussed in literature. Here, we have estimated the intensity of predation (both drilling and peeling) on Recent turritelline gastropods from the Indian subcontinent, which has been underrepresented in previous studies. Our samples include our own collections from several Indian coasts as well as a vast collection which was locked in the archive of the Zoological Survey of India (ZSI) in Kolkata for the past 150 years. It includes samples from different parts of the Indian subcontinent as well as from many other countries. Drilling frequency (DF) of Indian turritelline species is low compared to average values of global data. We suggest that this is mainly because most of the Indian species are larger (> 4 cm) than species living elsewhere. Smaller species show higher DF and lower values of peeling frequency. Size selectivity of drill holes shows both intra- and interspecific variation. Shell thickness and ornamentation appear to be antipredatory in nature.

We have compared our results with a revised global database. Distribution of intensity of predation shows latitudinal variation where both drilling and peeling frequencies increase towards the tropics.

Life history parameters, including size-age, production, mortality and size at reproductive maturity, were studied on the edible snail Adelomelon ancilla to provide useful management data. Stable oxygen isotope ratios confirmed semiannual formation of internal growth marks. Adelomelon ancilla can reach up to 18 years at a size of 150 mm, fitting to a Gompertz growth model. Size at which 50% of the population matured was 73.5 mm in males (7 years) and 93.5 mm in females (9 years). The long lifespan of this species is comparable to other large gastropods, in particular volutids from southern Atlantic Ocean. Longevity, low somatic production, low population density, late reproductive maturity and direct development with few embryos, makes A. ancilla a vulnerable resource that will require a proper management approach incorporating estimates of these life history parameters.

Sphaeriids represent a highly diverse family of small bivalves inhabiting freshwater habitats worldwide. They are recognized for their high dispersal capacity as well as for a high capability to adapt to such extreme environments as high mountain regions over 4,000 m above sea level (a.s.l.). The Tibetan Plateau, located in central Asia, is such a high elevation area. Here, we present the first broad spatial sampling of sphaeriids from the Tibetan Plateau, which allowed us to describe the Recent fauna as well as their biogeographical background. Our study revealed six sphaeriid species inhabiting various habitats on the Tibetan Plateau: Pisidium nitidum, P. stewarti, P. subtruncatum, P. zugmayeri, Pisidium sp. I and Musculium kashmirensis. Four species are newly recorded for this region. Based on phylogenetic analyses using molecular information from three different genes (COI, 16S and 28S) we conclude that the extant diversity of Tibetan Plateau sphaeriids might have been caused by multiple colonization events. Furthermore, the zoogeographic affinities of Tibetan Plateau sphaeriids are mostly related to the Palearctic. Similar patterns have been observed in previous studies of other freshwater molluscan taxa in the area.

The mechanisms of sperm transfer, storage, utilization and digestion are crucial for understanding processes of postcopulatory sexual selection. Previous studies analysing postcopulatory processes have generally focused only on the ultimate outcome of the interactions between male and female sexual selection (paternity patterns). For a mechanistic understanding of the fate of received sperm and the involved patterns of postcopulatory sexual selection new techniques are required. Here we present an improved immunolabelling technique to track the fate of 5-bromo-2′-deoxyuridine (BrdU)-labelled sperm in the female reproductive organs of gastropods. The technique was tested in individuals of the simultaneously hermaphroditic land snail Arianta arbustorum (Linnaeus, 1758). We determined the percentage of labelled sperm in spermato-phores delivered and assessed the reliability of detecting labelled sperm in the spermatheca (sperm storage organ) and bursa copulatrix (sperm digestion organ) of the recipients. In our tests, the proportion of sperm labelled among the sperm produced by an individual averaged 99.3%. Furthermore, labelled sperm could be consistently visualized in both the sperm storage and sperm digestion organ of all recipients examined. Combined with a traditional sperm staining technique, we showed that the BrdU-labelling technique allows usto distinguish between sperm from two males in the female reproductive tract of double-mated snails. In a controlled growth experiment, we found that repeated BrdU-application slightly retarded shell growth of juvenile snails, but did not influence their adult size, survival, number of sperm delivered and mating frequency. The technique presented could be adjusted to other gastropod species providing insight into mechanisms of sperm competition and cryptic female choice.

The morphology of Calliostoma adspersum, C. depictum and C. hassler, from the Brazilian coast, were studied in detail. Their anatomy has particularities that may be unique to the genus, such as: presence of an ampulla in the female; reduction or loss of the cephalic lappets; presence of a pseudoproboscis; occurrence of the intestinal loop outside the head-foot haemocoel. At species level, we conclude that C. vinosum is a synonym of C. hassler, because specimens identifiable as both species occur within a single ontogenetic series. Calliostoma hassler can be distinguished by: lack of the left dorsal esophageal fold, absence of a gastric spiral caecum and presence of an intestine with two wide loops. Based on anatomical evidence, we concluded that C. depictum is not a synonym of C. adspersum, differing by strongly convex whorls and a distinct suture; a marked groove near the columella; an odontophore partially covered by the mid-esophagus; absence of the pair of odontophore muscles m8a; a ventral esophageal fold of the same size as the dorsal folds; and a reduced spiral caecum with 0.5 whorl.