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Sex hormones play an essential role in sexual differentiation, maintenance of sexual characteristics, gamete maturation, and mating behavior. However, very little is known about their dynamics in molluscs. We conducted a study on sex hormone (17β-estradiol, testosterone, and progesterone) concentrations in male and female Strombus pugilis to identify their variations at different gonadal stages. A total of 90 organisms (30 per month) were collected in February, September, and November 2016. The gonadal digestive gland complex of each specimen was dissected and divided into two sections. One section was set in alcoholic Bouin's fluid and processed with classic histological techniques; the second was macerated with 80% ethanol to extract steroids and analyzed by enzyme immunoassays. Histological section analysis was used to classify gonadal development into three stages: gametogenesis, mature, and undifferentiated. Mature females were observed in September. Testosterone and 17β-estradiol concentrations in both sexes were highest in the mature stage. In S. pugilis, 17β-estradiol, progesterone, and testosterone were all present, with higher concentrations associated with reproductive activity.

Aliger gigas is an economically important and vulnerable marine species. We present a new mitogenome of A. gigas from the Mexican Caribbean and use the eight publicly available Strombidae mitogenomes to analyze intra- and interspecific variation. We present the most complete phylogenomic understanding of Hypsogastropoda to date (17 superfamilies, 39 families, 85 genera, 109 species) to revisit the phylogenetic position of the Stromboidea and evaluate divergence times throughout the phylogeny. The A. gigas mitogenome comprises 15,460 bp including 13 PCGs, 22 tRNAs, and two rRNAs. Nucleotide diversity suggested divergence between the Mexican and Colombian lineages of A. gigas. Interspecific divergence showed high differentiation among Strombidae species and demonstrated a close relationship between A. gigas and Strombus pugilis, between Lambis lambis and Harpago chiragra, and among Tridentarius dentatus/Laevistrombus canarium/Ministrombus variabilis. At the intraspecific level, the gene showing the highest differentiation is ATP8 and the lowest is NAD4L, whereas at the interspecific level the NAD genes show the highest variation and the COX genes the lowest. Phylogenomic analyses confirm that Stromboidea belongs in the non-Latrogastropoda clade and includes Xenophoridea. The phylogenomic position of other superfamilies, including those of previously uncertain affiliation, is also discussed. Finally, our data indicated that Stromboidea diverged into two principal clades in the early Cretaceous while Strombidae diversified in the Paleocene, and lineage diversification within A. gigas took place in the Pleistocene.

Although protocols exist for the recovery of ancient DNA from land snail and marine bivalve shells, marine conch shells have yet to be studied from a paleogenomic perspective. We first present reference assemblies for both a 623.7 Mbp nuclear genome and a 15.4 kbp mitochondrial genome for Strombus pugilis, the West Indian fighting conch. We next detail a method to extract and sequence DNA from conch shells and apply it to conch from Bocas del Toro, Panama across three time periods: recently-eaten and discarded (n = 3), Late Holocene (984-1258 before present [BP]) archaeological midden (n = 5), and mid-Holocene (5711-7187 BP) paleontological fossil coral reef (n = 5). These results are compared to control DNA extracted from live-caught tissue and fresh shells (n = 5). Using high-throughput sequencing, we were able to obtain S. pugilis nuclear sequence reads from shells across all age periods: up to 92.5 thousand filtered reads per sample in live-caught shell material, 4.57 thousand for modern discarded shells, 12.1 thousand reads for archaeological shells, and 114 reads in paleontological shells. We confirmed authenticity of the ancient DNA recovered from the archaeological and paleontological shells based on 5.7× higher average frequency of deamination-driven misincorporations and 15% shorter average read lengths compared to the modern shells. Reads also mapped to the S. pugilis mitochondrial genome for all but the paleontological shells, with consistent ratios of mitochondrial to nuclear mapped reads across sample types. Our methods can be applied to diverse archaeological sites to facilitate reconstructions of the long-term impacts of human behaviour on mollusc evolutionary biology.

Although protocols exist for the recovery of ancient DNA from land snail and marine bivalve shells, marine conch shells have yet to be studied from a paleogenomic perspective. We first present reference assemblies for both a 623.7 Mbp nuclear genome and a 15.4 kbp mitochondrial genome for Strombus pugilis, the West Indian fighting conch. We next detail a method to extract and sequence DNA from conch shells and apply it to conch from Bocas del Toro, Panama across three time periods: recently-eaten and discarded (n=3), Late Holocene (984-1258 BP) archaeological midden (n=5), and a mid-Holocene (5711-7187 BP) paleontological fossil coral reef (n=5). These results are compared to control DNA extracted from live-caught tissue and fresh shells (n=5). Using high-throughput sequencing, we were able to obtain S. pugilis nuclear sequence reads from shells across all age periods: up to 92.5 thousand filtered reads per sample in live-caught shell material, 4.57 thousand for modern discarded shells, 12.1 thousand reads for archaeological shells, and 114 reads in paleontological shells. We confirmed authenticity of the ancient DNA recovered from the archaeological and paleontological shells based on 5.7x higher average frequency of deamination-driven misincorporations and 15% shorter average read lengths compared to the modern shells. Reads also mapped to the S. pugilis mitochondrial genome for all but the paleontological shells, with consistent ratios of mitochondrial to nuclear mapped reads across sample types. Our methods can be applied to diverse archaeological sites to facilitate reconstructions of the long-term impacts of human behavior on mollusc evolutionary biology.

In the southern Gulf of Mexico, the spotted eagle ray (Aetobatus narinari) is the second most frequently caught batoid in small-scale fisheries off Campeche. Ecological aspects of this ray are unknown in this region, hampering the understanding of the relationship between its distribution and prey availability in the fishing area. In order to study the feeding habits of this batoid and characterize its potential prey in the study area, stomachs and intestines of 154 specimens (68 females and 86 males) were analysed. The results indicated thatA. narinarinear Campeche is a specialist and selective predator that feeds mainly on gastropods (92.7% IRI), with no significant differences in the diet found between sexes, size groups, or between stomach and intestine contents. In addition, the results indicated that the most important prey species in the diet were among the most common benthic species in three of the four sampling transects positioned in or adjacent to fishing areas for rays. These most important prey species wereStrombus pugilis(53.33% IRI) andAmericoliva reticularis(25.6% IRI). Other prey species includedLobatus costatus(5.6% IRI) andPetrochirus diogenes(3.6% IRI). This study suggests that this widely distributed ray species feeds in Campeche's coastal waters and that the study of its potential prey increases the understanding of ecological aspects of the species, which emphasizes the added importance of monitoring fishery impacts on prey species (e.g. the conch fishery off Campeche) to help support integrated assessment and management of fisheries.

International audience; Crypt cells—one of the three cell types composing Strombidae digestive tubules—are characterized by the presence of numerous metal-containing phosphate granules termed spherocrystals. We explored the bioaccumulation and detoxification of metals in Strombidae by exposing wild fighting conch Strombus pugilis for 9 days to waterborne CuSO4 and ZnSO4. The total amount of Cu and Zn was determined in the digestive gland and in the rest of the body by Inductively Coupled Plasma (ICP) analyses. The digestive gland spherocrystal metal content was investigated based on the semi-quantitative energy dispersive X-ray (EDX) elemental analysis. ICP analyses of unexposed individuals revealed that 87.0 ± 5.9% of the Zn is contained in the digestive gland, where its concentration is 36 times higher than in the rest of the body. Regarding Cu, 25.8 ± 16.4% of the metal was located in the digestive gland of the control individuals, increasing to 61.5 ± 16.4% in exposed individuals. Both Cu and Zn concentrations in the digestive gland increased after exposures, pointing to a potential role of this organ in the detoxification of these metals. EDX analysis of spherocrystals revealed the presence of Ca, Cl, Fe, K, Mg, P, and Zn in unexposed individuals. No difference was found in the relative proportion of Zn in spherocrystals of exposed versus control individuals. Contrastingly, copper was never detected in the spherocrystals from controls and Zn-exposed individuals, but the relative proportion of Cu in spherocrystals of Cu-exposed individuals varied from 0.3 to 5.7%. Our results show the direct role of spherocrystals in Cu detoxification.

An important ark clam (Arca zebra) artisanal fishery takes place in the east region of Venezuela. Besides the target species, trawling extracts a significant bycatch of several mollusk species including the gastropod Voluta musica, a threatened species according to the Ven ezuelan Red List of Endangered Species. In this paper we evaluate: 1) the composition of mollusk species in the bycatch, 2) the number of individuals of V. musica caught as bycatch and, 3) the abundance and size structure of the exploited populati on. Each fishing night, about 27,830 m2 are trawled by each boat extracting on the average 607 kg of A. zebra meat and 19 kg of V. musica (whole shelled animal). This fishery activity potentially captures ~30,000 kg of ark clam meat and 922 kg of V. musica in one week (~95 snails/fishing night/boat). The size structure of the V. musica population at the ark clam bed is significantly smaller than in other nearby sites not impacted by trawling fishing activities. Non-targeted species extracted in the bycatch but consumed by the local inhabitants include the gastropods Chicoreus brevifrons, Phyllonotus margaritensis, P. pomum, Fasciolaria tulipa, Strombus pugilis, a few Trochidae species, and the bivalves Pinctada imbricata, Spondylus americanus, Anadara florid ana, A . notabilis, and Trachicardium muricatum. Individuals of V. musica along with several invertebrates are discarded. We recommend that V. musica should not be neglected as a conservation target, and despite that A. zebra fisheries are considered “artisanal”, that more strict regulations should be established on it. La pesca artesanal de la almeja arca (Arca zebra) es una de las pesquerías de mayor importancia en el oriente de Venezuela. En esta pesquería se capturan incidentalmente varias especies de moluscos, incluyendo el gasterópodo Voluta musica, considerada amenazada según el Libro Rojo de la Fauna Venezolana. En este trabajo se evalúa: 1) la composición de especies de moluscos en la captura incidental, 2) el número de individuos de V. musica capturados como pesca incidental y 3) la estructura de tallas y abundancia de la población explotada. En cada faena de pesca se arrastran 27.830 m 2 por cada barco, extrayendo en promedio 607 kg de A. zebra (sin concha) y 19 kg de V. musica (con concha). La flota completa captura ~30.000 kg de A. zebra y 922 kg de V. musica en una semana (~95 caracoles/noche de pesca/barco). La estructura de tallas de la población de V. musica en el banco de A. zebra es significativamente menor comparada con sitios cercanos no afectados por la pesca de arrastre. Otras especies capturadas incidentalmente son consumidas por los habitantes loca les e incluyen los gasterópodos Chicoreus brevifrons, Phyllonotus margaritensis, P. pomum, Fasciolaria tulipa, Strombus pugilis, y unas pocas especies de Trochidae, bivalvos Pinctada imbricata, Spondylus americanus, Anadara floridana, A . notabilis, Trachicardium muricatum. Los individuos de V. musica y otros invertebrados son desechados completamente. V. musica debe ser considerada como objeto de conservación, y a pesar que la captura de A. zebra es considerada "artesanal", se deberían establecer regulaciones más estrictas sobre esta especie. Fil: Peralta, Ana Carolina. Universidad Simón Bolívar; Venezuela Fil: Miloslavich, Patricia. Universidad Simón Bolívar; Venezuela Fil: Carranza, Alvar. Universidad de la República; Uruguay Fil: Bigatti, Gregorio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Instituto de Biología de Organismos Marinos; Argentina

Stages from oviposition to veliger hatching are described for Strombus pugilis under laboratory conditions. Two egg masses from Playa Seyba, México, (20"45' N, 91°45' W) were used (three sub-samples per mass). Each sub-sample was immersed in a 11 container at 29 ± 1°C. This description is based on stages known from Strombus gigas, which include number of: fertilized eggs, morulae, gastrulae; trochophore larvae with slow movements, larvae with primordium foot, larvae with eyes, larvae with statocyst and veliger larvae. Eggs with first division appeare d five hours after oviposition in the three replicates of each mass, although in greatest number in one of the egg masses. Trochophore larvae with slow move­ments appear after 50-54 hours and veligers hatch after 90 hours. Se describe el desarrollo embrionario de Strombus pugilis hasta la eclosión de las larvas veligeras en condi­ciones de laboratorio. Se trabajó con dos masas de huevos (tres submuestras de tres centímetros). Cada sub­muestra fue colocada en un recipiente plástico de un litro a 29 ± 1°C. Se usó diez características embiológicas de Strombus gigas: número de huevos fertilizados, huevos con la primera división celular, huevos con la segunda división celular, número de mórulas, número de gástru­ las, número de larvas trocóforas con movimientos lentos, número de larvas con primordio del pie, número de lar­vas con ojos, número de larvas con estatocistos y número de larvas velígeras recién eclosionadas. Los huevos fer­tilizados aparecieron, en general, a la media hora de la ovoposición. Los huevos con la primera división aparecieron por primera vez a la hora con cinco minu­tos en las tres submuestras, aunque en mayor número en una de ellas. Las larvas trocóforas con movimientos lentos aparecieron entre las 50 y 54 hr. La eclosión de las larvas velígeras inició a la hora con 90 minutos a partir de la ovoposición.

The combined influence of feeding schedule and photoperiod on fighting conch, Strombus pugilis (Linne, 1758) larvae growth and survival was studied using two feeding schedules (12 h and 24 h with food) and three photoperiods (0 h light, 12 h light and 24 h light). This effect of feeding and photoperiods was tested in three months (May, June and July). Shell length was measured every two days to establish growth for each treatment. For the three experiments, continuous darkness and feeding were advantageous for larvae growth with the higher growth rate (42 μm d − 1 ) while continuous light and feeding had a negative effect on growth (29 μm d − 1 ) and survival (13%). However the highest survival (44%) was obtained in 12 h light and 24 h feeding.

Introduction Jamaica was inhabited by two separate groups of pre-Columbian people. The Ostionoid, or as James Lee called them, the Redware people arrived approximately A.D 650 ± 120^sup 2^, settling several known sites on the southwestern coast and on the central northern coast of the island as well. Then a later migration of Meillacan Ostionoid pottery-making people presumably from central Hispaniola arrived, approximately 1073 B.P^sup 3^ ± 95 or A.D 948 (Allsworth- Jones, 2008, p. 99). These were the Taino. They successfully settled most of the coastal areas of the island as well as many inland sites. Both cultures were technologically Ceramic Age peoples, who used the durable materials around them to fabricate and develop their material world, the hardwood trees, natural fibres, a large variety of stones, both igneous and sedimentary, and the shells collected primarily as food, which they used secondarily in their industrial and decorative arts. However, it is the indigenous use of shells and corals which fascinated me. Having been a practicing goldsmith, I understood the skill required in turning natural raw materials into naturally fabricated things of beauty, but pre-Columbian peoples were far superior in skill and ingenuity in their use of the seashell, compared to present-day manufacturers of shell craft items. From a careful study of certain worked artefacts (presented below) it appears that the Jamaican Tainos' understanding of the natural symmetry and internal structure of various gastropod shells (Figure 1) was advanced and equal to the skill of Mesoamerican (Mayan) craftsmanship (Scheie & Miller, 1 992, plates 27, 59, 85, 113, 121), or Aztec, or indeed the Classic Taino craftsmanship as seen on the other Greater Antillean islands of Hispaniola, Eastern Cuba and Puerto Rico (Bercht et al, 1998, plates 25, 26, 34, 85, 102). Though these cultures used Gastropod shells to make fantastic works of wearable art, their artisans relied on incision techniques and carvings on the surface of the shell to convey their ideas visually. The Jamaican Taino, however, seemed to prefer the use of the natural internal structure of the shells' columellas to translate and communicate ideas and imagery. Thus in my estimation their understanding of the shells' true decorative ability was far superior to the other previously named cultures. The most often used univalve shells were classified as the true conchs (Dance, 1992, pp. 57-64). The term 'conch' is used to designate a number of shell varieties, even those that do not belong to the true conch shell gastropod family as do the Strombus gigas (Queen conch), the Strombus gallus (Rooster Tail conch), Strombus raninus (Hawk Wing conch) and the Strombus pugilis (West Indian Fighting conch), which are common Caribbean varieties of the sea snails. Living in warm shallow waters, feeding on eel grasses and scavenging through coral sands, they often move into deeper waters as they reach the end of their reproductive maturity, although never to depths of more than 70 feet. At this depth their shells, which consist primarily of calcium carbonate bonded by a protein called conchiolin, start to thicken and lose their customary rippled appearance, as in the case of the Queen conch (Strombus gigas). This rippling can be found on the larger outer lip or flare of the Strombus gigas shell (Figure 2). However as this shell ages the rippled surface starts to attain a flattened appearance. In some cases this flattening is minimal and in others the flattening is complete, leaving a smooth sloping surface. The snail can live for 20 to 40 years. This longevity also influences the amount of horizontal rippling or ridges present on the body whorl, which continues to the outermost rim of the lip as well as to the thickness of the outer lip. The Melongena melongena or West Indian Crown conchs are also a variety of sea snail, and are not considered true members of the conch family though colloquially they are called by that name. …

Fighting conch Strombus pugilis is one of six Strombidae species distributed throughout the Caribbean. It is used as food, as an aquarium organism and its shell are popular in jewelry production. Conch aquaculture has been done traditionally by extracting egg masses from wild adults. This is an issue for several conch species protected by CITES. Intensive conch culture requires good growth rates and gonad maturity under laboratory conditions using formulated feed. An evaluation was done of the effect of inclusion of the red algae Halymenia and Spirulina on gonad maturity in S. pugilis using two experimental diets containing low and high concentrations of these algae (2% and 8% of each). Each diet was fed to six groups of conch kept in 20 L aquaria at 27.5°C. They were fed twice daily at 0.1 g feed/conch for 105 days. Gonad development and digestive gland structure were analyzed with histological techniques. Analysis of gonad development and vitellus granule diameter were analyzed for the two treatments and a control (wild conch). Wild conch females exhibited a reproductive cycle with 100% maturity at the beginning of this study, followed immediately by spawning (in two peaks: 50% and 34%) and initiation of a new oogenesis cycle. Females fed the 8% H. floresii and 8% Spirulina diet exhibited two spawning peaks (75% and 100%) spaced a month apart, and larger yolk granules than those in the control and the 2% H. floresii and 2% Spirulina diet. Proteoglycan granule abundance in the digestive cells did not differ between treatments. H. floressi and Spirulina may function as a feeding stimulant, enhancing feed intake and promoting gonadal maturity in S. pugilis broodstock under laboratory conditions.

International audience; The organogenesis, histogenesis and growth of larvae of the fighting conch Strombus pugilis (Linne, 1758) were studied over a period of 30 d after hatching in laboratory culture. Early development of S. pugilis was examined by light and scanning electron microscopy. Rearing was conducted at 27 +/- 1 degrees C. Veligers were reared at 200 larvae l(-1) in 4-l containers. Larvae were fed with the microalgae Isochrysis galbana and Nanochloropsis oculata at a concentration of 1,000 cell l(-1). The protoconch at hatching measured 212 +/- 12.14 mu m in length and the shell reached 1,100 +/- 29.11 mu m 29 d after hatching. Development characteristics are described from hatching to settlement. Newly hatched veligers possess two velar lobes, a larval shell consisting of 1.5 whorls, eyespots and a single right tentacle. Late veligers (5-d old larvae) have four velar lobes and two shell whorls and the left tentacle appears. Pediveligers show a functional adult heart at 11 d. Crawling behaviour and settlement were observed from 27 to 31 d. Plantigrades were observed after 29 d, when a functioning proboscis is observed and the velar lobes are lost. This study will facilitate the identification of gastropod larval shells in the plankton and of juveniles in the meiobenthos and will aid aquaculture of Strombus species.

On the Yucatan Peninsula there is an upwelling which allows access to a body of cold water that controls temperature in this area. This modulates the ecology and distribution of organisms that inhabit the continental shelf. The objective of this study was to determine the effect of different acclimation temperatures on the thermal biology of prey as mollusc, crustacean (Melongena corona bispinosa, Strombus pugilis, Callinectes similis, Libinia dubia) and predators as fish (Ocyurus chrysurus, Centropomus undecimalis) of Octopus maya. Octopus prey preferred temperatures between 23.5°C and 26.0°C, while predators preferred temperatures 26.4-28.5°C. The species with largest thermal windows were M. corona bispinosa (328.8°C(2)), C. similis (322.8°C(2)), L. dubia (319.2°C(2)), C. undecimalis (288.6°C(2)), O. chrysurus (237.5°C(2)), while the smallest thermal window was for S. pugilis (202.0°C(2)). The acclimation response ratios (ARR) estimated for prey ranged from 0.24-0.55 in animals exposed to CTMax and 0.21-0.65 in those exposed to CTMin. Amongst predators, ARR ranged from 0.30 to 0.60 and 0.41 to 0.53 for animals exposed to CTMax and CTMin, respectively. Correlating the optimal temperature limits of prey and predators with surface temperatures on the continental shelf and those 4m deep showed that the main prey, Callinectes similis and L. dubia, shared a thermal niche and that an increase in temperature could force these species to migrate to other sites to find optimal temperatures for their physiological functions. As a consequence the continental shelf community would undergo a structural change. Predators were found to be near their optimal temperatures in surface temperatures on the continental shelf. We conclude that they would remain in the area in a warming scenario. The size of the thermal window was related to the type of ecosystem inhabited by these species. These ARR intervals allowed us to categorize the species as temperate or tropical, according to the oceanographic conditions that prevail on the Yucatan Peninsula.

The processes of gonad development through a year are analyzed for Strombus pugilis from Seybaplaya, Campeche. During gametogenesis second order oocytes appear close to the wall of the follicles, with a diameter 90–250 μm. The cytoplasm is granular, the nucleus is located on the periphery, with a diameter of 15–35 μm, a nucleolus 7–8 μm. Spermatozoids have an acrosome of 5–7 μm, shaped like a coma. In females gametogenesis was registered in two pulses, with 2 peaks of 60%, February to June and September to October. Mature females were found during the 8 months of sampling with peaks during May and August (80%). Spawning was discontinuous, suggesting storage of mature gametes for the right time to spawn. In males gametogenesis was present in a low percentage from March to October, with a maximum of 20%. Maturity was present on just a 10% during July, with constant spawn through the year. Copula has been observed only during egg laying seasons; males seem to keep mature sperms in the prostate gland...

The discovery of an intact valve of the fossil bivalve Chesapecten jeffersonius and shells of three tropical snail species in a c. 1610 James Fort well speaks to the curiosity that European colonists brought to the New World. While implementing the Virginia Company of London's mandate to identify and secure profitable natural resources, the Jamestown, Virginia, colonists apparendy also gathered interesting natural objects. The shells may have been collected either as personal souvenirs, much like modern-day tourists, or as curios destined for the lucrative European conchology market. Chesapecten jeffersonius, Virginias state fossil, was collected locally as representatives can still be found in James River Pliocene deposits near Jamestown. In contrast, the tropical shells were likely brought to Jamestown in May 1610 by survivors of an English shipwreck on Bermuda. The shells from both Virginia and Bermuda were discarded in the forts well by June 1610 as the settlers hastily prepared to permanendy abandon Jamestown.

Intensive size-selective harvesting can drive evolution of sexual maturity at smaller body size. Conversely, prehistoric, low-intensity subsistence harvesting is not considered an effective agent of size-selective evolution. Uniting archaeological, palaeontological and contemporary material, we show that size at sexual maturity in the edible conch Strombus pugilis declined significantly from pre-human (approx. 7 ka) to prehistoric times (approx. 1 ka) and again to the present day. Size at maturity also fell from early- to late-prehistoric periods, synchronous with an increase in harvesting intensity as other resources became depleted. A consequence of declining size at maturity is that early prehistoric harvesters would have received two-thirds more meat per conch than contemporary harvesters. After exploring the potential effects of selection biases, demographic shifts, environmental change and habitat alteration, these observations collectively implicate prehistoric subsistence harvesting as an agent of size-selective evolution with long-term detrimental consequences. We observe that contemporary populations that are protected from harvesting are slightly larger at maturity, suggesting that halting or even reversing thousands of years of size-selective evolution may be possible.

The genus Strombus is widely distributed in the Caribbean. Six species are of commercial importance: S. gigas, S. raninus, S. costatus, S. alatus, S. gallus and S. pugilis. Economically, the Queen conch, S. gigas is the most important and consequently the most widely studied. However, since 1970 a decline of S. gigas populations due to over-fishing has been observed. Many authors have studied S. gigas hatchery rearing techniques in order to address this problem; however, for these hatchery techniques to be successful, an adequate diet must be provided for the larvae. Some information of the nutritional requirements of S. gigas larvae have been reported since 1965, but a nutritionally complete diet is still not available. In this work we summarize the different diets that have been used for S. gigas, S. costatus and S. pugilis larvae rearing. Twenty one different algae species have been used: Amphidinium carteri, Chaetoceros gracilis, Dunaliella tertiolecta, Emillania huxleyi, Heterocapsa pygmacea, Isochrysis (Caicos), Isochrysis (Tahiti), Isochrysis sp., Monochrysis sp., Nannochloris, Nitzchia, Platymonas sp., P. tetraselmis, Prorocentrum minimun, Rhodomonas sp., Skeletonema costatus, Tetraselmis chuii, Tetraselmis sp., T. suecica, Thalassiosira fluviatilis and T. weissflogii. There are other diets that have seldom been studied with Strombus veliger larvae, that could be a potential food source for these gastropods. The type and concentration of algae, larval rearing conditions are summarized along with the results attained in larval growth, metamorphosis, survival, ingestion and digestion rates.

Fighting conch, Strombus pugilis , larvae were reared from hatching to settlement under three photoperiods, with light phases of 0 light (0 L), 12 light (12 L) and 24 light (24 L) per day to test their effect on development, growth and survival. Proboscis appeared at 21 days in different percentages for three photoperiods: 30% for larvae under 0 L, 50% for larvae under 12 L and 54% for larvae under 24 L. For the three photoperiods the veligers were competent for metamorphosis between 27 to 31 days. Under 0 L conditions frequency of metamorphosis was lower. The settlement period was similar in 24 L and 12 L conditions, but the duration was significantly longer below 0 L conditions. Continuous light had a negative effect on survival, while continuous darkness was advantageous. The percentage of survival at settlement was significantly lower under 24 L (13%) and 12 L (22%) conditions, while 0 L was 44%. Larval growth averaged 22.56, 23.36 and 29.60 μm dia. −1 below 0 L, 12 L and 24 L conditions, respectively. The siphonal length at settlement was longer for larvae under 24 L than that below 0 L and 12 L conditions.

International audience; Strombus gigas and Strombus pugilis are threatened species and aquaculture represents a good alternative solution to the fishing. In this study, we highlighted the intracellular digestion process in the digestive gland of two Strombidae species, S. gigas and Strombus pugilis, by the cytochemical characterization of two lysosomal enzymes: acid phosphatase and arylsulfatase. In order to check the efficiency of artificial food digestion, we onducted the characterization on freshly collected, tarved and artificially fed individuals of S. pugilis. TEM observations of digestive gland sections from freshly collected individuals of both species revealed the resence of acid phosphatase and arylsulfatase activity mostly located in the apical third of digestive cells. Both enzymes were also detected in artificially fed individuals. In response to the starvation, acid phosphatase is not produced anymore by digestive cells, while arylsulfatase is still present. To our knowledge, this is the first cytochemical validation of intracellular digestion of artificial food in Strombidae. This study highlights the intracellular digestion of artificial food developed for Strombidae aquaculture. Moreover, we have shown that the lysosomal activity could be used as a feed index.

Digestive tubules of Strombidae are composed by three cell types: digestive cells, vacuolated cells, and crypt cells. The last one is characterized by the presence of intracellular gran- ules identified as spherocrystals. Such structures are known to occur in basophilic cells of gastro- pod digestive gland, where they are supposed to be involved in the regulation of some minerals and in detoxification. In this study, energy-dispersive X-ray analysis (EDX) and energy filtered trans- mission electron microscopy (EFTEM) were used to determine the elemental content of spherocrys- tals in two Strombidae, Strombus gigas and Strombus pugilis. In freshly collected individuals of both species, the following elements were detected: Ca, Fe, Mg, P, and Zn. Aluminum and Mn were also detected in S. gigas. Their presence in spherocrystals indicates that, in Strombidae, sphero- crystals are involved in the regulation of minerals and essential trace metals. In order to answer the question ''are spherocrystals involved in nonessential trace metals scavenging?,'' artificial cad- mium and lead exposure by both waterborne and dietary pathways was applied to S. pugilis .N o evidence of cadmium (Cd(NO3)2) or lead (Pb(NO3)2) provided by food was found in spherocrystals. Cadmium provided in water (Cd(NO3)2 and CdCl2) causes structural modifications of the digestive gland; however, this element was not trapped in spherocrystals. These results suggest that spher- ocrystals are not involved in detoxification of such nonessential trace metals. Microsc. Res. Tech.

A escala local, la variación en el espacio de la abundancia inter-específica suele presentar autocorrelación espacial (muchos "puntos fríos" dispersos con escasos o ningún individuo, y pocos "puntos calientes" agrupados con abundancia mucho mayor). Esto genera, dentro del hábitat, sitios vacíos con condiciones que parecen favorables. Por ende, conocer la distribución espacial de la abundancia de una especie y las características ambientales que la influencian, permite establecer lugares estratégicos para su manejo y conservación. Con esta investigación se estableció, para la época húmeda, el patrón espacial de la distribución de la abundancia del caracol marino Strombus pugilis en el sector comprendido entre Riohacha y el Cabo de la Vela en la costa Guajira colombiana y variables ambientales que en parte lo explican. Para esto seutilizaron técnicas de geoestadística y modelos aditivos generalizados (GAM). Se encontraron 8.384 adultos y 462 juveniles en 56.920 m2 muestreados. La mayor parte de la densidad del caracol se encontró agregada en el nororiente del sector, dentro del ambiente arenal, sin diferencias entre juveniles y adultos. La densidad promedio de S.pugilis estimada (0,143±0,109 ind/m2) es baja comparada con lo registrado para la especie en otro sitio. Lo mismo ocurre con la talla promedio de los adultos (adultos: 6,9±0,52 cm, juveniles: 5,1±0,79 cm). En cuanto a las variables ambientales, las mayores densidades de adultos y juveniles se presentaron en sitios con profundidades entre 10 y 15 m y con porcentajes de materia orgánica del sedimento entre 4 y 6 %. Adicionalmente, las mayores densidades de adultos se relacionaron con tamaños medios de grano del sedimento entre 0,5 y 1,0 φ (arenas gruesas). Sin embargo, la presencia de sitios favorables (en cuanto a las variables medidas) que no estaban ocupados por la especie, permite pensar que la agregación local puede deberse a otros factores que no fueron tenidos en cuenta en este estudio. / Abstract. Locally, the inter-specific abundance variation in the space usually has autocorrelation (many "cold spots" scattered with little or no individuals, and few hot spots" grouped with much higher abundance). This generates, in the habitat, empty sites with conditions that appear favorable. Therefore, knowing the abundance spatial distribution of a species and the environmental characteristics that influence it enable the localization of strategic places for management and conservation purposes. This research establishes, for the wet season, the spatial pattern of the abundance distribution of the fighting conch Strombus pugilis in the sector between Riohacha and Cabo de la Vela in the Colombian Guajira coast, and some environmental variables that in part explain it. For this, geostatistics techniques and generalized additive models (GAM) were used. In 56920 m2 sampled were found 8384 adults and 462 juveniles. Most of the snail density is aggregated in the northeast of the sector, in the sandy environment, without differences between juveniles and adults. The estimated average density of S. pugilis (0.143±0.109 ind/m2) is low compared with records for the species in other site. The same applies to the average size of the adults (adults: 6.9±0.52 cm, juveniles: 5.1±0.79 cm). For the environmental variables, the highest densities of adults and juveniles occurred at sites with depths between 10 and 15 m, with percentages of sediment organic matter between 4 y 6 %. Additionally, the highest densities of adults were associated with average sediment grain sizes between 0.5 y 1.0 φ (coarse sand). However, the presence of favorable sites (in terms of the measured variables) that were not occupied by the species, suggest that local aggregation may be due to other factors not considered in this study Maestría

Submitted by Guilherme Lemeszenski (guilherme@nead.unesp.br) on 2013-08-22T18:54:33Z No. of bitstreams: 1 S0101-81752001000100006.pdf: 881196 bytes, checksum: fd77ea145096b20c8f0cf7bceb547062 (MD5) Made available in DSpace on 2013-08-22T18:54:33Z (GMT). No. of bitstreams: 1 S0101-81752001000100006.pdf: 881196 bytes, checksum: fd77ea145096b20c8f0cf7bceb547062 (MD5) Previous issue date: 2001-03-01 Made available in DSpace on 2013-09-30T19:46:31Z (GMT). No. of bitstreams: 2 S0101-81752001000100006.pdf: 881196 bytes, checksum: fd77ea145096b20c8f0cf7bceb547062 (MD5) S0101-81752001000100006.pdf.txt: 8452 bytes, checksum: 84727caa92a4e01e0757890abcfddc2d (MD5) Previous issue date: 2001-03-01 Submitted by Vitor Silverio Rodrigues (vitorsrodrigues@reitoria.unesp.br) on 2014-05-20T15:12:19Z No. of bitstreams: 2 S0101-81752001000100006.pdf: 881196 bytes, checksum: fd77ea145096b20c8f0cf7bceb547062 (MD5) S0101-81752001000100006.pdf.txt: 8452 bytes, checksum: 84727caa92a4e01e0757890abcfddc2d (MD5) Made available in DSpace on 2014-05-20T15:12:19Z (GMT). No. of bitstreams: 2 S0101-81752001000100006.pdf: 881196 bytes, checksum: fd77ea145096b20c8f0cf7bceb547062 (MD5) S0101-81752001000100006.pdf.txt: 8452 bytes, checksum: 84727caa92a4e01e0757890abcfddc2d (MD5) Previous issue date: 2001-03-01 Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) The present work is the first report of Dardanus venosus (H. Milne Edwards, 1848) in São Paulo State and extends the range of this species in the western Atlantic farther to the south in the Brazilian region. A total of twenty two males (mean shield length: 7.56 ± 1.62 mm, 4.7 to 10.9 mm), and fifteen females (7.25 ± 2.53 mm, 4.3 to 14.5 mm) were collected in 1987, 1998, 1999 and 2000 by scuba diving from three areas of Anchieta Island (23º33'S, 45º05'W) in the Ubatuba region, and south of São Sebastião Island (23º57.8'S, 45º16'W), northern coast of São Paulo State. No ovigerous females were captured during the study period. Shells of eleven gastropod species were occupied by D. venosus: Astraea latispina (Philippi, 1844), A. olfersii (Philippi, 1846), A. phoebia Roding 1798, Calliostoma bullisi Clench & Turner 1960, Chicoreus tenuivaricosus (Dautzenberg, 1927), Cymatium parthenopeum (von Salis, 1793), Olivancillaria urceus (Röding, 1798), Phalium granulation (Born, 1778), Stramonita haemastoma (Linnaeus, 1767), Strombus pugilis Linnaeus, 1758 and Zidona dufresnei (Donovan, 1823). Universidade de São Paulo Faculdade de Filosofia, Ciências e Letras de Ribeirão Preto Departamento de Biologia USP FFCLRP Curso de Pós-Graduação em Biologia Comparada Universidade Estadual Paulista Instituto de Biociências Departamento de Zoologia Universidade Estadual Paulista Instituto de Biociências Departamento de Zoologia

Se determinó la supervivencia, reproducción y el desarrollo embrionario del caracol Strombus pugilis, por un periodo de diez meses en condiciones de laboratorio. Siete progenitores fueron recolectados en Isla Contoy, Quintana Roo, México y posteriormente trasladados al laboratorio donde fueron colocados en acuarios de 80 l con agua de mar y alimentados con alimento granulado. Un total de 30 masas ovígeras fueron recolectadas, lográndose un aumento en el número de masas de huevos en abril. La longitud total estimada de una sola masa ovígera fue de 11.24 m, el número promedio de embriones encontrados en 2 cm fue de 264, obteniéndose un total de 157 500 embriones en toda la masa de huevos. Los resultados promedio de los parámetros físico-químicos a lo largo del periodo de estudio fueron los siguientes: salinidad de 37.5±0.5 ‰, pH 7.5±0.5 y temperatura de 28±0.2 °C. Con los datos aportados en este estudio se infiere que este sistema de mantenimiento y recirculación de los progenitores es excelente tanto para la reproducción como para la obtención de las masas ovígeras en condiciones controladas.Obtaining of egg masses of the snail, Strombus pugilis (Mesogastropoda: Strombidae) under laboratory conditions. The survival, reproduction and embryonic development of Strombus pugilis, were determined during a period of ten months under laboratory conditions. Seven progenitors were collected in Contoy Island, Quintana Roo, Mexico and later transferred to the laboratory, where they were placed in aquarium with 80 l of sea water and fed with "pellets". A total of 30 egg masses were collected, one on September and the other on April. The estimated total length of one egg mass was 11.24 m; the mean number of embryos obtained per 2 cm was 264, obtaining an estimated total of 157 500 embryos in the egg mass. The means of the physical-chemical parameters during the study were: salinity 37.6±0.5 ‰, pH 7.5±0.5 and temperature 28±0.2 °C. The maintenance and water recirculation system used to sustain the breading stock is excellent both for reproduction of the organism and for obtaining egg masses under controlled conditions. Rev. Biol. Trop. 55 (1): 183-188. Epub 2007 March. 31.

During normal operation Angra dos Reis Nuclear Power Plant (Rio de Janeiro, Brazil) releases, into the Sea, radioactive effluents which need to be monitored. Among the released radionuclides, the Co-60 is set off because of its long half-life also because is it an essential element for several metabolic processes in biota.

A detailed comparative morphology of the following 21 species is made: 1) Strombidae: Strombus pugilis (Brazil), S. alatus (Florida, USA), S. gracilior (form Panama, Pacific coast), Eustrombus goliath (Brazil), E. gigas (Caribbean), Aliger costatus, A. gallus (northeastern Brazil), Tricornis raninus (Caribbean); Conomurex luhuanus, Canarium urceus, Lambis lambis, Terebellum terebellum (all Australia), Tibia insulaechorab (Pakistan); 2) Struthiolariidae: Struthiolaria papulosa (New Zealand), Tylospira scutulata (Australia); 3) Aporrhaidae: Cuphosolenus serresianus new comb., Aporrhais occidentalis and A. pespelicani (North Atlantic and Europe); 4) Xenophoridae: Onustus caribaeus and Xenophora conchyliophora (West Atlantic) and O. indicus (Australia). The three former families are usually considered members of the superfamily Stromboidea, while the Xenophoridae are included in their own superfamily Xenophoroidea. A phylogenetic (cladistic) analysis is undertaken, based on 102 characters (255 states); with some basal Caenogastropoda as the main outgroup. A single most parsimonious tree was obtained (length: 209, CI: 74; RI: 86) as follows: ((T. scutulata - S. papulosa) (C. serresianus ((A. occidentalis - A. pespelicani)((O. caribaeus - O. indicus) - X. conchyliophora)(T. terebellum (C. urceus (C. luhuanus (T. raninus (L. lambis (S. pugilis - S. alatus - S. gracilior)((E. goliath - E. gigas) (A. costatus - A. gallus))))))))))). According to this analysis, Stromboidea (including Xenophoridae) is a monophyletic superfamily supported by 42 synapomorphies, Xenophoridae and Strombidae are monophyletic, as well as Strombus, Aliger and Eustrombus are monophyletic genera; whereas Aporrhaidae and Aporrhais are paraphyletic taxa; the Xenophoridae are the sister taxon of the Strombidae. Lambis lambis is represented in a branch within species currently included in Strombus, thus some genera were revalidated (Eustrombus and Aliger) and subgenera require elevation to genera (Strombus s.s., Tricornis, Conomurex, Canarium).

1. 1. The respiratory responses of Murex pomum and Strombus pugilia to different temperatures and salinities were monitored. 2. 2. The b value for Murex at ambient temperature and salinity was 0.97, with a negative exponent of −0.03. 3. 3. Their rates of oxygen uptake between approx. 23 and 32°C rose and fell with increased and decreased temperature respectively. 4. 4. Both species appear to be stenohaline osmoconformers which do not expend extra energy above and below their optimum salinity range.

Strombus pugilis [spec. nov.] S. testae labro antico prominente rotundato, laevi, spira spinosa, cauda triloba. List. conch. t. 906. f. 26. Bonan. recr. 3. t. 299. Gvalt. test. t. 32. f. B. Argenv. conch. t. 18. f. A. Habitat ad Jamaicam. Faux rubra est, testa crocea., Published as part of Linnaeus, Carolus, 1758, Systema Naturae per regna tria naturae: secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis, Stockholm :Laurentius Salvius on page 744, DOI: 10.5962/bhl.title.542, http://zenodo.org/record/3922206

Made available in DSpace on 2022-04-29T08:42:42Z (GMT). No. of bitstreams: 0 Previous issue date: 2000-01-01 The objective of this study is to investigate the patterns of shell utilization in Petrochirus diogenes in the Ubatuba region, SP, Brazil. Hermit crabs were obtained from 1993 to 1996 with the aid of a shrimp fishery boat equipped with two double-rigged trawling nets. Shells were identified and weighed, and their maximum aperture width was measured. Hermit crabs were weighed, and their shield length was recorded. A total of 634 P. diogenes specimens, occupying shells of 12 gastropod species, was obtained. The shells of Tonna galea, Zidona dufresnei and Strombus pugilis were the most frequently occupied, the first marked by its larger aperture width and lower average weight. Small hermit crabs inhabited a wide variety of gastropod shells due to their higher availability. However, the utilization of T. galea shells became predominant as the crabs attained larger sizes. Differences in weight and aperture width are known to encourage certain shell utilization patterns and may affect growth and reproduction of hermit crabs. Grp. Studs. Crustacean Biol. Ecol. Departamento de Zoologia Inst. Biociencias-Univ. Estadual P., 18618-000 Botucatu (São Paulo)