Monetaria Annulus Research Articles

Community structure of macroinvertebrates in protected and exploited areas of Baganga, Davao Oriental, Philippines

Macroinvertebrates are vital in coastal marine environments, which function as ecologically (e.g., food chain) and socio-economically (e.g., income generation for coastal gleaners). Different anthropogenic activities, including unregulated gleaning, pose potential threats to the assemblages of macroinvertebrates. However, studies related to assessing and comparing the community structures of macroinvertebrates in protected and exploited areas are poorly documented in the Philippines. Hence, this study aims to provide valuable information to formulate proper fisheries management, including the protection and conservation of macroinvertebrates and their supporting habitats. Fishery-independent and fishery-dependent surveys were conducted in three coastal barangays of Baganga, Davao Oriental, Philippines: one protected (control site) in Ban-ao and two exploited (gleaning grounds) in San Victor and Kinablangan to determine macroinvertebrate community structure and document local gleaning activities. Seventeen (17) macroinvertebrates were recorded, comprising nine (9) mollusks, three (3) crustaceans, and five (5) echinoderms. Four species (4) were abundant in the study sites: Dardanus sp., Monetaria annulus, Thalamita crenata, and Trochus maculatus. The community structure of macroinvertebrates in both exploited areas was influenced by gleaning of the coastal residents, resulting in lower species richness, density, and diversity compared to the protected area where collection was highly restricted. There is a need to ensure the sustainability of gleaning in these areas by providing protection on the existing macroinvertebrates in the area through a formulation of local subsistence fisheries management.

Chemical Synthesis and Characterization of Hydroxyapatite Prepared from Cypraea Annulus

In the last decade, the processes involved in biomineralization has greatly developed, leading to the production of a new generation of biomaterials. Calcium phosphate ceramic materials attract special interest due to their bioactive and biocompatible properties in biomaterials. Most of marine structures contains calcium carbonate (calcite or aragonite) and they can be easily converted to bioceramic material. The application of calcium phosphate ceramics as useful biocompatible materials largely depends on the purity and morphology of the powder. In this study calcium phosphate bioceramics (as raw materials for bone-scaffolds) were obtained via hot-plate, ultrasound-assisted, and microwave assisted method using the sea shell Cyprae Annulus as a calcium source. The characterization of the produced materials was carried out via FT-IR, SEM, XRD analysis. It was found that the calcium phosphate powders (hydroxyapatite) produced by three different methods were predominantly monetite and hydroxyapatite as the secondary phase. According to the SEM results, the overall morphology for CaP powder bioceramics shows the regular distribution of spherical and rice-shaped and CP powders produced by microwave assisted method have better morphology. The used methods are safe and inexpensive. Moreover, the raw materials (Cypraea Annulus) feature the advantages of the unlimited source as well as the biological origin. These methods were compared takes attention due to it is economical and easy method to obtain hydroxyapatite.

Distribution of Cowries in the Different Ecological Habitats in the Selected Sites in Davao Occidental

Aims: The primary aim of this study was to assess the species of cowries in the different ecological habitats of Barangay Buhangin, Tubalan, and Tanglad, Davao Occidental. Specifically, it sought to identify species of cowries found in the study area, population density, abundance, and diversity.
 Place and Duration of Study: Barangay Buhangin, Tubalan, and Tanglad, Davao Occidental, April 10 – 30, 2022.
 Methodology: The study employed a transect-line-quadrat method. There were three stations were established in the selected areas. The quadrat was used to determine the density, abundance, dominance, and diversity of cowries. A 1m x 1m quadrat was thrown randomly on the established layout of 50 ㎡ (25m x 2m) parallel to the shore. Gears, such as diving goggles and snorkel were used to determine the cowries inside the quadrat and were hand-picked for species identification.
 Results: The study revealed that there were ten (10) species of cowries recorded and identified. In Station 1 (Barangay Buhangin), seven species were found namely: Monetaria annulus (Gold ring cowry), Cypraea tigris (Tiger cowry), Mauritia arabica (Arabian cowry), Monetaria caputserpentis (Serpent’s head cowry), Naria erosa (Eroded cowry), Monetaria moneta (Money cowry) and Luria isabella (Fawn-coloured cowry). In Station 2 (Barangay Tubalan) two species were recorded and identified, namely: Cypraea tigris (Tiger cowry) and Mauritia arabica (Arabian cowry), while in Station 3 (Barangay Tanglad), eight species were recorded and identified, these were: Monetaria annulus (Gold ring cowry), Cypraea tigris (Tiger cowry), Mauritia arabica (Arabian cowry), Naria erosa (Eroded cowry), Monetaria moneta (Money cowry), Lyncina vitellus (Calf cowry), Lyncina lynx (Eyed cowry), and Palmadusta asellus (Littleass cowry). In Station 1, Coral Reef Habitat has the most diverse species with five (5) species found, while the seagrass bed habitat is the most abundant in terms of population with nine (9) cowries found, and the mangrove habitat only houses one (1) species of cowry with a population of three (3).
 Conclusion: Station 3 was the most diverse in terms of cowry species with 8 species identified. Station 1 and Station 2 have the highest population of juvenile cowry species with a total of 127 juvenile species, and Station 2 has the highest population of adult cowry species with a total of 17 adult species. There were four (4) cowry species found in the mangrove habitat, four (4) cowry species were also found in the seagrass bed habitat and nine (9) cowry species were found in the coral reef habitat thus making it the most diverse among all ecological habitats.

Community distribution and utilization of gastropods in the Coastal Area of Liki Island, Sarmi District, Papua, Indonesia

Abstract. Sujarta P, Mailissa MG, Keiluhu HJ, Hadisusanto S, Yuliana S. 2022. Community distribution and utilization of gastropods in the Coastal Area of Liki Island, Sarmi District, Papua, Indonesia. Biodiversitas 23: 5001-5011. Gastropods and snails are mollusk phylum animals with diverse species that inhabit and spread in various marine ecosystems. The main objective of this study was to determine the structure of gastropod communities and their utilization in the coastal area of Liki Island, Sarmi District, Papua, Indonesia. Samples of gastropods were collected through descriptive-quantitative surveys using the line-transects technique. In addition, information on the utilization of gastropods was collected from surveys with semi-structural interviews with selected respondents from Liki Island, the outermost island in East Indonesia, with a total area of 1318.54 ha. The result showed a total of 1812 living specimens from 63 species of gastropods from 23 families, collected from six sampling stations, with 182-603 specimens on average. There were five species of gastropods encountered in all sampling stations, namely Conus litteratus (family of Conidae), Monetaria moneta, Monetaria annulus (Cypraeidae), Oxymeris crenulata (Terebridae), and Polinices flemingianus (Naticidae). The highest Importance Value Index (IVI) belonged to Nerita albicilla (Neritidae) from Station 1 (IVI 58.45). In contrast, the lowest belonged to the species of Nassarius limnaeiformis (Nassariidae), Oliva caerulea, and Oliva oliva (Olividae) from Station 4 (each IVI 2.56), with the moderate value of Shannon-Wiener Diversity Index and low value of Dominance Index. People in the coastal area of Liki Island use 12 species of gastropod as wall ornaments and consume 12 species of gastropod, as well. In general, the people of Liki Island use gastropods wisely based on the socio-cultural characteristics of the local community.

Stringing Together Cowrie Shells in the African Archaeological Record with Special Reference to Southern Africa

Archaeological explorations of the meaning of ‘trade objects’, such as glass beads and cowrie shells, remain hampered by theoretical and methodological limitations in both their analyses and interpretations. In this paper, we develop a methodology for critically engaging in multi-scalar questions of the circulation, exchange, and value of cowrie shells in African archaeological contexts. Species, size, dorsal modifications, and depositional contexts were compared across five sites from South Africa dating between 750 and 1350 CE. These results were positioned within a review of cowries from archaeological sites in the region and compared to the documented distribution of cowries from wider African archaeological contexts. Monetaria annulus were the prevalent cowrie species in southern African archaeological contexts over the last 2000 years, with a notable absence of Monetaria moneta, prevalent at contemporaneous sites in West Africa, as well as a variety of endemic southern African species. Breakage patterns on the dorsal surface correspond to different modification techniques, such as chipping and grinding. Combined analyses of modification, use-wear, and depositional patterns show variation, revealing a diversity in the biographies of individual cowries. While a comparison of the distribution of cowries across the continent confirms the circulation of cowries through known trade routes, such as the trans-Saharan trade network and the European mercantile network, they also reveal new pathways for exchange that highlight the need for further exploration of intra African networks. Finally, the breadth of the results of this study demonstrates the value of a focus on a specific artefact to address a wide range of themes, from exchange to the archaeology of everyday life.

High temperature stress does not distort the geochemical thermometers based on biogenic calcium carbonate: Stable oxygen isotope values and Sr/Ca ratios of gastropod shells in response to rearing temperature

Quantitative profiles of stable isotopes and trace elements in biogenic carbonates have received considerable attention for the purpose of reconstructing past temperatures. The relationships between temperature and the geochemical parameters of carbonates are often subject to both inter- and intraspecific variations, which critically impair the accuracy of temperature estimation. One of the issues that must be addressed to improve temperature estimation is enhancing our understanding of the influence of the kinetic effect. This effect matters because the purely thermodynamic effect to geochemical profiles cannot be effectively separated from the effect of temperature-driven calcification rate. Cowries (Mollusca, Gastropoda, Cypraeidae) may provide a good model system for quantitatively investigating these two effects, because they undergo a callus-building stage in which aragonitic shell formation exclusively occurs to monotonically increase the thickness outward. We reared a total of 230 juvenile individuals of Monetaria annulus under six constant thermal regimes, ranging from the minimum growing temperature (21 °C) to the maximum tolerated long-term temperature (34 °C). The portions of the shells built in the callus-building stage were analyzed to quantify isotopic and elemental compositions. Shell growth rate positively depended on temperature from 21 °C to 33 °C, but dramatically decreased at 34 °C, presumably because of high temperature stress. Nevertheless, the heat stress did not make any impact on the thermal dependences (and among-individual variabilities within the same temperature) of either δ18Oc or Sr/Ca. A linear relationship exists between temperature and the stable oxygen isotope value of the shells (δ18Oc) across the entire thermal range (n = 103), whereas the shell Sr/Ca ratio increased exponentially with increasing temperature (n = 227). These results strongly suggest that any chemical processes responsible for quantitative incorporation of 18O and Sr into aragonite crystals were not impacted by heat stress at temperatures up to 34 °C. Within-temperature residual correlations between shell growth rates and δ18Oc were weakly positive, which is compatible with a widely accepted hypothesis that carbonic anhydrase suppresses the kinetic effect in molluscs. Likewise, we found no association between shell growth rates and Sr/Ca, which rejected the possibility that faster CaCO3 precipitation caused the positive relationship between temperature and Sr/Ca. A large proportion of among-individual variability in shell Sr/Ca was caused by unspecified factors other than temperature. This makes it difficult to accurately estimate the past temperature by measuring the Sr/Ca value of a single shell specimen.

Molecular Phylogenetic Analysis of Turbo brunneus (R.1798), Cypraea annulus (L.1758) and Babylonia spirata (L.1758)

Over the past few decades, biologists from many disciplines have turned to phylogenetic analyses to interpret variation in biological systems. Phylogenetic relationships with a high potential in the absence of sufficient morphological characters can be resolved by molecular phylogenetic techniques according to coded characters. A number of mtDNA genes have been targeted in marine gastropods for phylogenetic purpose; these include the ribosomal RNA genes 28S, 18S, 16S and 12S, Cytochrome oxidase I (COI) and cytochrome b (Cyt-b). In the present study, SSU rRNA in Turbo brunneus, 18S rRNA in Cypraea annulus and COI gene in Babylonia spirata were successfully amplified and sequenced. Phylogenetic tree of the three species were constructed by using neighbor-joining tree. The optimal tree with the sum of branch length = 1.47445020 was observed. Turbo brunneus was phylogenetically closer to the clade of Cypraea annulus than that of Babylonia spirata. The mitochondrial genomes are informative for mollusc phylogeny, which give a proper phylogenetic approach.

Home for Marine Species: Seagrass Leaves as Vital Spawning Grounds and Food Source

Seagrass beds provide nursery habitats for marine species. Seagrass leaves, in particular, are used as spawning grounds and food source for fishes and invertebrates, but direct evidence of spawning in seagrass leaves is rare. It is also very challenging to identify eggs through morphological analysis, since the eggs of many marine species appear similar. To accurately identify the eggs on the leaves of the dominant seagrass species in the South China Sea, and evaluate seasonal contribution of seagrass leaves as food source, DNA barcoding and stable isotope technique were conducted. Interestingly, Monetaria annulus was found to spawn on the leaf sheath of Thalassia hemprichii in Li'an gang, Hainan Island. This selection of oviposition site might increase embryo survival compared to the other parts of the seagrass leaves. Meanwhile, the eggs of Stethojulis trilineata were deposited on the entire leaf of Halophila ovalis in Liusha Bay, Guangdong Province. The small fingernail-shaped leaves of H. ovalis might be beneficial for S. trilineata to lay eggs as they are closer to the sediment surface than other seagrass leaves. Based on the stable carbon and nitrogen isotope analyses, the primary food source of M. annulus in summer and in winter were particulate organic matter and seagrass, respectively. The results suggest that seagrass leaf is not only important for fish and invertebrates as a spawning site, but also as a food source. The findings of the present study may support the urgent requirement of the conservation of seagrass beds for sustaining the productivity of marine fisheries.

Species density and shell morphology of gold ring cowry (Monetaria annulus, Linnaeus, 1758) (Mollusca: Gastropoda: Cypraeidae) in the coastal waters of Ambon Island, Indonesia

Abstract. Latupeirissa LN, Leiwakabessy F, Rumahlatu D. 2020. Species density and shell morphology of gold ring cowry (Monetaria annulus, Linnaeus, 1758) (Mollusca: Gastropoda: Cypraeidae) in the coastal waters of Ambon Island, Indonesia. Biodiversitas 21: 1391-1400. The purpose of this research was to examine environmental factors, species density, and the shell morphology of Monetaria annulus. The samples were collected by using the line transect method at 6 research stations. The data of the environmental factors (temperature, salinity, and pH of seawater) as well as species density of M. annulus were collected with in-situ technique, while the shell morphology of M. annulus was measured at Laboratory of the Deep-Sea Research Center, Indonesian Institute of Sciences (LIPI) Ambon. The results of the measurements of the environmental factors in the coastal waters of Ambon Island showed some fluctuations in the measurement values. The seawater temperature ranged between 29.78-30.05 ºC, the salinity of seawater ranged from 32.12-32.33‰, and the pH of the seawater ranged from 8.34-8.49. The density of M. annulus at the research stations from the highest to the lowest was at Tanjung Tiram station, Suli station, Seri station, Hutumuri station, Halong station, and Latuhalat station (0.27 > 0.24 > 0.23 > 0.19 > 0.14 > 0.12 ind/m2). The results of the measurement of the shell morphology showed many variations in the size and shape of the shell of M. annulus with a total number (N) of 294 individuals. The length, the width, and the height of the shell, the length of the blotches, the width of the blotches, and the total weight of M. annulus from each research station were significantly different (p<0.005). These results indicate that the differences in the shell morphology of M. annulus at each research station were influenced by waves, the strength of the currents sea waves, and the different substrate of water. In addition, the variation of shell morphology can be a reason for characterization in the taxonomy of the Cypraeidae family.

Cataloging Cowries: A Standardized Strategy to Record Six Key Species of Cowrie Shell from the West African Archaeological Record

Two species of the cowrie shell, Monetaria moneta (Linnaeus, 1758) and Monetaria annulus (Linnaeus, 1758), repeatedly occur in archaeological contexts across West Africa. Despite their archaeological and ethnographic importance, these shells remain poorly and inconsistently reported in the archaeological literature. The absence of standardized data on species composition, size, and condition of cowrie assemblages, and whether and how the shells were modified, make it difficult to examine their significance in a regional and chronological framework. To address this problem, we propose a set of standardized criteria and coding system for recording cowrie assemblages—in particular, species, size, condition, and state of modification. We aim to enable nonshell specialists within the wider archaeological community to securely identify intact or modified specimens of M. annulus and M. moneta, showing how these can be distinguished from four cowrie species native to West Africa—Luria lurida (Linnaeus, 1758), Zonaria zonaria (Gmelin, 1791), Zonaria sanguinolenta (Gmelin, 1791), and Trona stercoraria (Linnaeus, 1758). We demonstrate how accurate species identification and the assessment of proportions of different sizes of shells within suitably large assemblages can provide insight into their provenance. This information can enhance our appreciation of the exchange networks within which these shells moved. We also identify five different strategies documented in the archaeological record that were used to modify cowries, detailing how these can be differentiated and classified. The aim here is to suggest a recording strategy that will enable comparisons of the use and value of cowries in West Africa and elsewhere.

GASTROPODS COMMUNITIES IN THE MANGROVE ECOSYSTEM WAISISIL BEACH SAPARUA DISTRICT MALUKU

The gastropods community in the mangrove ecosystem on the Waisisil beach, Saparua District, Maluku consists of 14 gastropod species, namely Clypeomorus batillariaeformis, Cypraea annulus, C. moneta, Hebra corticata, Littorina scabra, Morula margariticola, Nasarius olivaceus, Natica euzona, Nerita chamaeleon, N, signata, Otoplueura auriscati, Pyrene ocellata, Strombus labiatus, Terebralia sulcata. The species with the highest number of individuals was C. batillariaeformis and the species with the lowest number of individuals was C. annulus. The gastropod community in the mangrove ecosystem on the Waisisil beach has a species diversity index (H') = 1.8, evenness index (E) = 0.7, and dominance index (D) = 0.3.

The mitochondrial genome of the gold-ringed cowry Monetaria annulus (Mollusca: Gastropoda: Cypraeidae) determined by whole-genome sequencing

The mitochondrial genome of the cowry snail Monetaria annulus (Caenogastropoda: Cypraeoidea: Cypraeidae) was determined by whole-genome next-generation sequencing. The mitogenome is composed of 13 protein-coding genes (PCGs), 2 ribosomal RNA (12S and 16S) genes, and 22 transfer RNA genes (tRNAs). This gene order is consistent with the previously published mitochondrial genomes of other species belonging to the order Littorinimorpha. The superfamily Cypraeoidea was recovered as a sister clade to the group of Tonnoidea and Neogastropoda.

ASOSIASI GASTROPODA DENGAN TUMBUHAN MANGROVE PADA EKOSISTEM PANTAI DI NEGERI TIOUW DAN NEGERI HARIA KECAMATAN SAPARAUA KABUPATEN MALUKU TENGAH

Background: Mangrove forests are one of the unique natural ecosystems with high ecological value. Mangrove ecosystems are one of the areas with high productivity because there are litter and decomposition of litter and detritus occurs. This study was conducted to determine the association between gastropods and mangrove plants.
 Method: Research on gastropod association with mangrove plants in the coastal waters of Tiouw Village and Haria Village was conducted in January 2018.
 Results: This study found from gastropods 6 species namely variabilis strombus, microurceus strombus, Nassarius luridus, Strombus urceus, Cypraea annulus, Strombus, Strombus, Nerita squamulata. From the mangrove plants, 10 species were found: Avicennia eucalyptifolia, Avicennia lanata, Bruguiera sexangula, Rhizophora apiculata, Bruguiera hainessi, Aegiceras floridum R, Aegiceras curniculatum L, Bruguiera palviflora, Bruguiera exaristafa, Ceriops tagal.
 Conclusion: Association values ​​ranged from 0.741-0.9773 with positive and negative types. This means that both types of seagrass are often found together or not found together in the observation location

ASOSIASI GASTROPODA DENGAN TUMBUHAN LAMUN DI PERAIRAN PANTAI NEGERI TIOUW KECAMATAN SAPARUA KABUPATEN MALUKU TENGAH

Background: Seagrasses are flowering plants (Angiosperms) that are able to adapt fully in waters with high salinity or live immersed in water. Seagrass has true rhizomes, leaves and roots like plants on land. Seagrasses usually form fields called seagrass beds, especially in tropical and sub-tropical regions. The existence of seagrasses is known to support fishing activities, shellfish communities and other invertebrate biota.
 Method: This study is a descriptive study to reveal information about environmental characteristics, and associations of seagrasses with gastropods.
 Results: The study found a class of gastropods, 10 species namely Strombus variabilis, Strombus microurceus, Nassariusl uridus, Nassarius dorsatus, Strombus urceus, Cypraea annulus, Strombus labiatus, Strombus marginatus, Neritas quamulata, Cypraeratigris. Of the seagrass plants found 4 species, namely Enhalus acoroides, Thalassia hemprichii, Halophila ovalis, Cymodocea rotundata. Association values ​​ranged from 4.159-8.85 with positive and negative types. This means that both types of seagrass are often found together or not found together in each observation box.
 Conclusion: There is a weak association between seagrass and gastropods in the coastal waters of Tiouw State. The association of gastropod types with seagrass species is found in 10 types of gastropods and 4 types of seagrasses in the waters of the Tiouw State coast

Struktur Komunitas Moluska di Padang Lamun Perairan Kepulauan Padaido dan Aimando Kabupaten Biak Numfor, Papua

<strong>Community Structure of Mollusca in Seagrass Beds Padaido and Aimando Islands Biak Numfor Regency, Papua.</strong> Mollusca is one of marine biota which is commonly found in seagrass beds and largely utilized by inhabitants in Biak. However, information about the diversity and abundance of mollusca in Padaido Aimando Islands, Biak Papua is still limited. The research about mollusca composition in the seagrass beds of Padaido Aimando Islands, Biak was conducted in April – October 2014. Sampling method using quadrat transect from the beach toward the sea at 15 stations. Mollusca samples preserved in alcohol 40%, then it was cleaned and identified in the laboratory. In this research was found 239 species of mollusca, which consists of 177 species from Gastropods and 62 species from Bivalves. Mollusks gastropod that have high distribution is <em>Monetaria annulus, Conomurex luhuanus</em> dan <em>Canarium urceus</em>, while of class Bivalvia is <em>Anadara antiquata</em>. The highest value index of species diversity (H) is found at Station 7 (3.951) and the lowest at Station 14 (3.077). Value index of species richness (d) ranged between 9.041 and 10.883 and evenness index value (J) ranged between 0.768 and 0.99. While the dominancy index ranged from 0.020 to 0.092. Based on similarity index, Station 3 has a high similarity with station 4. This research provides valuable information on the diversity and abundance of mollusca which can be useful for decision making aimed at the management of mollusca resource in Biak.

DIVERSITY, COMPOSITION AND UTILIZATION OF MOLLUSC IN SAPARUA ISLAND, CENTER MOLUCCA

Saparua Island is one of the islands in the Central Moluccas that has a complete ecosystem, unfortunately records on mollusk research is very limited. The aim of this research is to know the composition, diversity and utilization of mollusk. The objectives of the study are to determine the composition, diversity and utilization of mollusks using square transect and free collection method which conducted on April and September 2016. Water analysis is also done to determine the environmental hydrographic condition. Temperature and salinity indicate the presence of freshwater input through rivers, especially in St-2 2 (Waisisil). Concentrations of nutrients show a fairly high value, ranging from 0.001 to 0.114 mg L-1 for phosphate; 0.012 - 0.023 mg L -1 for nitrate and 0.140 - 0.443 mg L -1 for silicate. There are 641 individual mollusks of 107 species consisting of 85 species of Gastropoda and 22 species of Bivalves. Species found mostly by Littoraria scabra (Littorinidae), Cypraea annulus (Cypreidae), Terebralia sulcata (Potamididae); Clypeomorus battilariaeformis (Cerithiidae); and Nerita chamaeleon (Neritidae). The existing mollusk community has moderate and uniform diversity with low species dominance. There are at least 35 species of mollusks that can be utilized into various commodities such as food products, accessories/decorations and raw materials of drugs.

Phenetic Relationship Study of Gold Ring Cowry, Cypraea Annulus (Gastropods: Cypraeidae) in Mollucas Islands Based on Shell Morphological

This study aims to construct taxonomic character of Cypraea annulus based on shell morphological; analyzed the developmental stages of the snail shell and investigated the similarities and phenotypic distances of snails with numerical taxonomic approaches. This research lasted four years on island of Larat and Ambon. The sample used was 2926. Construction of morphological taxonomic characters using binary data types with 296 test characters and ordinal types with 173 test characters; and 32 specimens of operational taxonomic units. The data is processed and analyzed on Lasboratory of Maritime and Marine Study Centre, University of Pattimura. The results of this study indicate that the development stages of C. annulus shell: juvenile stage (11.00-14.99 mm), sub adult (15.00-18.99 mm), adult (19.00-22.99 mm) and post adult (>23.00 mm). The distribution of similarity coefficient and phenetic distance values between 32 OTU C. annulus has a morphological phenetic similarity in the range of values above 95% and the phenetic distance in the range of less than 1.0. C. annulus numerical taxonomic based on morphological taxonomic character with 296 characters of test at binary data type, obtained two taxa phenotypes at a taxonomic phenon similarity level of 94%; Whereas with 173 character test of ordinal data type, obtained three taxa phenotype at taxonomic correlation level 0.970.

Intraspecific variations in shell calcification across thermal window and within constant temperatures: Experimental study on an intertidal gastropod Monetaria annulus

The relationship between temperature and shell growth was examined by rearing an intertidal cowrie species, Monetaria annulus (Gastropoda, Cypraeidae), at seven constant temperatures between 21°C and 34°C over four experimental years. Data on shell growth were collected during the callus-building stage, in which calcification exclusively occurs around the spiral shell constructed in the juvenile stage. Our experiments elucidated some clear trends among temperatures, although careful consideration is required to interpret the results obtained under the potential confounding factors between temperature and experimental year. Calcification was accelerated by increasing temperature in the range between 21°C and 33°C, and drastically slowed down at 34°C probably due to heat stress. No relationship was found between body size and callus growth rates. The duration of callus-building indicated a negative exponential relationship with rearing temperature. However, no simple relationship was found between temperature and final shell thickness; the final shell thickness described two peaks around 21°C and 30°C. This finding strongly suggests that a physiological control by calcifiers cannot be ignored to explain the thermal response of calcification rates. Our results also suggest that considering the thermal seasonality as well as the difference in mean temperature, is required to explain the negative latitudinal clines in shell thickness frequently observed in molluscan species. We also focused on the variation among the individuals reared at the same temperatures. Statistical analyses suggested that the final shell thickness and the duration of calcification were better described by the normal and lognormal distributions, respectively. The distribution of shell growth rates did not considerably deviate from the normal distribution with respect to skewness and kurtosis. However, their heteroscedasticity among temperatures was inherent and significant; its variance positively depended not on the mean but on temperature. The observed pattern might be an evidence that possible stabilization selection on calcification rates is more relaxed at warmer temperatures.

Reproductive seasonality of Monetaria annulus (Linnaeus, 1758) (Mollusca: Gastropoda: Cypraeidae) in a temperate area

The objectives of this study are: (1) to detect the developmental stages in the gonads of Monetaria annulus through histological analysis; (2) to determine the spawning season of this species in a temperate area through seasonal changes in the proportion of each gonadal stage; and (3) to analyse the sex ratio and sexual dimorphism through gonad histology. Samples were obtained randomly from an intertidal rocky shore in Hanazesaki, Ibusuki, Kagoshima Prefecture, Japan (31 11′30.10″N, 130 30′29.70″E) every 2 months from February 2011 to June 2012. Reproductive stages were identified and classified as Stage 1 (initial maturity), Stage 2 (peak maturity) and Stage 3 (spawned). Stage 2 males and females were found during more than half of the year, but their proportion varied seasonally. Although the reproductive peak was slightly different year by year in the temperate area, M. annulus seemed to have two reproductive seasons, in spring and from late summer to winter. The sex ratio was biased towards females, but it was not statistically significant. The mean shell length of females was significantly larger than that of males, though they overlapped widely.

Higher calcification costs at lower temperatures do not break the temperature-size rule in an intertidal gastropod with determinate growth

The vast majority of ectothermic organisms grow larger when developing at cooler environmental temperatures, a pattern frequently referred to as the temperature-size rule (TSR). Assuming that this reaction norm has adaptive significance, life history theory predicts that converse patterns may evolve if favored by natural selection, namely if the costs associated with complying to the TSR outweigh the benefits. Calcifying ectotherms may comprise such an exception not following the TSR, because calcification is expected to be more costly at lower temperatures thus increasing associated costs. To test this hypothesis, we reared wild-caught juveniles of the intertidal gastropod Monetaria annulus and compared their shell sizes at the end of the juvenile stage between two rearing temperatures. Contrary to our prediction, M. annulus does follow the TSR, suggesting that increased calcification costs at lower temperatures are not high enough to break the TSR. Such plastic responses should be considered when interpreting geographical patterns such as latitudinal size clines, which may be caused at least partly by phenotypic plasticity.