ABSTRACT Pupilla alluvionica Meng & Hoffmann, 2008 is an extant land snail species known until now only from a few sites in the Russian Altai Mountains. We have now identified it in fossil loess assemblages of Early-Middle Pleistocene age at three Central European sites. Fossil materials match those of Altaian populations, being only slightly smaller in mean shell width. In addition to the details of the locations and biometrics of these fossil finds, we list the faunas associated with P. alluvionica in the deposits. These are compared with the ecological conditions and associated faunas of living populations from the Altai. Pupilla alluvionica is a typical inhabitant of xeric habitats: steppes with rocky limestone outcrops. This matches the known habitat preferences of associated species in the fossil deposits that are typical of open loess steppe.
{"title":"Pupilla alluvionica Meng & Hoffmann, 2008: A Land Snail Extant in the Altai Refugium Recognised for the First Time in Central European Early-Middle Pleistocene Glacials","authors":"M. Horsák, L. Juřičková, J. Škodová, V. Ložek","doi":"10.4002/040.059.0203","DOIUrl":"https://doi.org/10.4002/040.059.0203","url":null,"abstract":"ABSTRACT Pupilla alluvionica Meng & Hoffmann, 2008 is an extant land snail species known until now only from a few sites in the Russian Altai Mountains. We have now identified it in fossil loess assemblages of Early-Middle Pleistocene age at three Central European sites. Fossil materials match those of Altaian populations, being only slightly smaller in mean shell width. In addition to the details of the locations and biometrics of these fossil finds, we list the faunas associated with P. alluvionica in the deposits. These are compared with the ecological conditions and associated faunas of living populations from the Altai. Pupilla alluvionica is a typical inhabitant of xeric habitats: steppes with rocky limestone outcrops. This matches the known habitat preferences of associated species in the fossil deposits that are typical of open loess steppe.","PeriodicalId":49895,"journal":{"name":"Malacologia","volume":"4 1","pages":"223 - 230"},"PeriodicalIF":1.3,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4002/040.059.0203","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70086246","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Abdel-Ghaffar, A. Ahmed, F. Bakry, Ibrahim Rabei, A. Ibrahim
ABSTRACT Schistosomiasis remains a public health problem in the developing world. Biomphalaria alexandrina is the intermediate host of Schistosoma mansoni, with a widespread distribution in Egypt. In Egypt molluscicides have been important, but otherwise molluscicides have been of minor significance. They may, however, become important now that WHO talks about eradicating schistosomiasis in some countries and that WHO has finally accepted that snail control is important.The present study investigated the different effects of three commercial herbicidical compounds, Butralin (as Amex 48% EC), glyphosate isopropylammonium (Herphosate 48% SL) and Pendimethalin (Stomp 50% EC) on B. alexandrina. All three compounds were found to have a molluscicidal effect, with Pendimethalin the most toxic over the examined range of concentrations. In addition, at sublethal concentrations, these compounds reduced growth rates and reproductive output (numbers of eggs laid) in exposed B. alexandrina, and it reduced viability of those eggs. Interpretion of assay data was supported by histological changes in the digestive and hermaphrodite glands of snails exposed at a range of concentrations. Moreover, the three compounds were also shown to rapidly (with three hours exposure) induce a toxic effect in miracidiae and cercariae of Schistosoma mansoni. It can be concluded that the three herbicidical compounds have molluscicidal and antihelminth properties.
{"title":"The Impact of Three Herbicides on Biological and Histological Aspects of Biomphalaria alexandrina, Intermediate Host of Schistosoma mansoni","authors":"F. Abdel-Ghaffar, A. Ahmed, F. Bakry, Ibrahim Rabei, A. Ibrahim","doi":"10.4002/040.059.0201","DOIUrl":"https://doi.org/10.4002/040.059.0201","url":null,"abstract":"ABSTRACT Schistosomiasis remains a public health problem in the developing world. Biomphalaria alexandrina is the intermediate host of Schistosoma mansoni, with a widespread distribution in Egypt. In Egypt molluscicides have been important, but otherwise molluscicides have been of minor significance. They may, however, become important now that WHO talks about eradicating schistosomiasis in some countries and that WHO has finally accepted that snail control is important.The present study investigated the different effects of three commercial herbicidical compounds, Butralin (as Amex 48% EC), glyphosate isopropylammonium (Herphosate 48% SL) and Pendimethalin (Stomp 50% EC) on B. alexandrina. All three compounds were found to have a molluscicidal effect, with Pendimethalin the most toxic over the examined range of concentrations. In addition, at sublethal concentrations, these compounds reduced growth rates and reproductive output (numbers of eggs laid) in exposed B. alexandrina, and it reduced viability of those eggs. Interpretion of assay data was supported by histological changes in the digestive and hermaphrodite glands of snails exposed at a range of concentrations. Moreover, the three compounds were also shown to rapidly (with three hours exposure) induce a toxic effect in miracidiae and cercariae of Schistosoma mansoni. It can be concluded that the three herbicidical compounds have molluscicidal and antihelminth properties.","PeriodicalId":49895,"journal":{"name":"Malacologia","volume":"59 1","pages":"197 - 210"},"PeriodicalIF":1.3,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4002/040.059.0201","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70086162","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACT Turritella duplicata (Linnaeus, 1758) is a marine suspension-feeding gastropod found in shallow-marine and tidal flat environments throughout Southeast Asia and the Indo-West Pacific. It was studied on a tidal flat in the national park of Nopparat Thara in the district of Krabi, southern Thailand. Turritella duplicata was found primarily in the lower intertidal zone, and 90 specimens were gathered and measured. Their geographical positions on the flat were mapped, revealing zonations in population distribution, both parallel and perpendicular to the shore-line. The size distribution of the shells indicates that the population consists exclusively of adults. δ18O sclerochronology performed on three shells shows variations of up to 1.5‰ associated with seasonal changes in water parameters, suggesting longevity of about three years and seasonally controlled growth rates. The absence of juveniles and observed population distribution coupled with the sclerochronological data suggest that reproduction occurs in early spring, and that the population represents three cohorts approximately one year in age and older. Migration to deeper water during other seasons cannot be ruled out. Smaller individuals were preferentially found on the inner tidal flat, and individuals older than two years preferentially colonised the outer tidal flat. The carbon isotopic composition of the analysed shells partially tracks these life stages, suggesting that metabolic “vital effects” are influencing the δ13C of the shells.
{"title":"Observations on the Biology and Sclerochronology of “Turritella” Duplicata (Linnaeus, 1758) (Cerithioidea, Turritellidae) from Southern Thailand","authors":"R. Waite, W. Allmon","doi":"10.4002/040.059.0206","DOIUrl":"https://doi.org/10.4002/040.059.0206","url":null,"abstract":"ABSTRACT Turritella duplicata (Linnaeus, 1758) is a marine suspension-feeding gastropod found in shallow-marine and tidal flat environments throughout Southeast Asia and the Indo-West Pacific. It was studied on a tidal flat in the national park of Nopparat Thara in the district of Krabi, southern Thailand. Turritella duplicata was found primarily in the lower intertidal zone, and 90 specimens were gathered and measured. Their geographical positions on the flat were mapped, revealing zonations in population distribution, both parallel and perpendicular to the shore-line. The size distribution of the shells indicates that the population consists exclusively of adults. δ18O sclerochronology performed on three shells shows variations of up to 1.5‰ associated with seasonal changes in water parameters, suggesting longevity of about three years and seasonally controlled growth rates. The absence of juveniles and observed population distribution coupled with the sclerochronological data suggest that reproduction occurs in early spring, and that the population represents three cohorts approximately one year in age and older. Migration to deeper water during other seasons cannot be ruled out. Smaller individuals were preferentially found on the inner tidal flat, and individuals older than two years preferentially colonised the outer tidal flat. The carbon isotopic composition of the analysed shells partially tracks these life stages, suggesting that metabolic “vital effects” are influencing the δ13C of the shells.","PeriodicalId":49895,"journal":{"name":"Malacologia","volume":"59 1","pages":"247 - 269"},"PeriodicalIF":1.3,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4002/040.059.0206","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70086380","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACT The Lepetidae are currently assumed to be represented by only one valid species in the Magellan region: Iothia emarginuloides (Philippi, 1868), of which Tectura (Pilidium) coppingeri Smith, 1881, and Iothia coppingeri magellanica Linse, 2002, were regarded as synonyms. The extant records of this species are scarce, although they suggest a wide distributional range in the Pacific Ocean, from off Concepción (36°S) to the Beagle Channel (55°S), and a restricted distribution in the Atlantic Ocean, where the species is only known from the Malvinas / Falkland Islands and Isla de los Estados (about 54.5°S). This study provides new information on the occurrence of the genus Iothia in the Magellan region, including morphological, anatomical and molecular evidence. The synonymy of Tectura (Pilidium) coppingeri, Iothia coppingeri magellanica and Iothia emarginuloides is ratified. The species is properly redescribed and figured, and its intraspecific variability discussed, particularly regarding its relation with depths. Furthermore, the distribution of this species in the southwestern Atlantic is extended north to San Matías Gulf (about 41°S). Iothia megalodon Warén, Nakano & Sellanes, 2011, previously known from deep waters off Concepción (36°S), is here reported for the first time for the Magellan region. Its finding in shallow waters from the Beagle Channel greatly extends its distribution both latitudinally and bathymetrically.
{"title":"Species of Iothia (Gastropoda: Lepetidae) from Shallow Waters of the Magellan Region","authors":"Marina Güller, D. Zelaya","doi":"10.4002/040.059.0210","DOIUrl":"https://doi.org/10.4002/040.059.0210","url":null,"abstract":"ABSTRACT The Lepetidae are currently assumed to be represented by only one valid species in the Magellan region: Iothia emarginuloides (Philippi, 1868), of which Tectura (Pilidium) coppingeri Smith, 1881, and Iothia coppingeri magellanica Linse, 2002, were regarded as synonyms. The extant records of this species are scarce, although they suggest a wide distributional range in the Pacific Ocean, from off Concepción (36°S) to the Beagle Channel (55°S), and a restricted distribution in the Atlantic Ocean, where the species is only known from the Malvinas / Falkland Islands and Isla de los Estados (about 54.5°S). This study provides new information on the occurrence of the genus Iothia in the Magellan region, including morphological, anatomical and molecular evidence. The synonymy of Tectura (Pilidium) coppingeri, Iothia coppingeri magellanica and Iothia emarginuloides is ratified. The species is properly redescribed and figured, and its intraspecific variability discussed, particularly regarding its relation with depths. Furthermore, the distribution of this species in the southwestern Atlantic is extended north to San Matías Gulf (about 41°S). Iothia megalodon Warén, Nakano & Sellanes, 2011, previously known from deep waters off Concepción (36°S), is here reported for the first time for the Magellan region. Its finding in shallow waters from the Beagle Channel greatly extends its distribution both latitudinally and bathymetrically.","PeriodicalId":49895,"journal":{"name":"Malacologia","volume":"20 1","pages":"321 - 330"},"PeriodicalIF":1.3,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4002/040.059.0210","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70086479","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACT Lithic particles are a common feature in the digestive tract of freshwater snails. Their role in the digestive processes has been demonstrated in some microphytophagous and detritivorous species, as they enhance growth, assimilation and reproduction. It has been suggested that they could have the same function in Pomacea canaliculata, a macrophytophagous apple snail with powerful jaws and radula, a strongly muscular and cuticularized gizzard and high levels of enzymatic activity. Our aims were to investigate the occurrence of lithic elements in the digestive tract of P. canaliculata snails from natural populations through the analyses of digestive contents, as well as the effect of size and availability of lithic particles on growth and growth efficiency through laboratory experiments. Lithic particles are very common in the digestive tract of P. canaliculata from natural populations and from laboratory aquaria if they are available in the immediate environment. Such particles are not retained or concentrated differentially in the stomach and they are apparently totally lost in less than four weeks if the supply is interrupted. The frequency of plant material and lithic particles increases from mouth to anus indicating that the retention time increases in the same way. Sand and plant material frequently co-occur in the intestine and in the stomach indicating that both are ingested together. Ground marble had negative effects on the growth of P. canaliculata probably due to the sharp edges and pointed ends of these particles. The availability of natural lithic particles (sand) had a positive effect on growth and also a synergic interaction with the availability of food. The growth efficiency was 25.2% higher when sand was available than when it was absent. These effects were more marked in juvenile females than in juvenile males. Our results indicate that growth rates may be underestimated under laboratory conditions if lithic particles are not supplied regularly and that their presence should be standardized to allow reliable comparisons between studies. Our results also indicate that the effects of food availability and plant palatability on the growth of P. canaliculata may be modulated by the presence of lithic particles and this may in turn affect the outcome of interactions between apple snails, other snails and macrophytes.
{"title":"Effects of Ingestion of Lithic Particles on Growth of the Apple Snail Pomacea canaliculata (Caenogastropoda, Ampullariidae)","authors":"E. Manara, L. Saveanu, P. Martín","doi":"10.4002/040.059.0202","DOIUrl":"https://doi.org/10.4002/040.059.0202","url":null,"abstract":"ABSTRACT Lithic particles are a common feature in the digestive tract of freshwater snails. Their role in the digestive processes has been demonstrated in some microphytophagous and detritivorous species, as they enhance growth, assimilation and reproduction. It has been suggested that they could have the same function in Pomacea canaliculata, a macrophytophagous apple snail with powerful jaws and radula, a strongly muscular and cuticularized gizzard and high levels of enzymatic activity. Our aims were to investigate the occurrence of lithic elements in the digestive tract of P. canaliculata snails from natural populations through the analyses of digestive contents, as well as the effect of size and availability of lithic particles on growth and growth efficiency through laboratory experiments. Lithic particles are very common in the digestive tract of P. canaliculata from natural populations and from laboratory aquaria if they are available in the immediate environment. Such particles are not retained or concentrated differentially in the stomach and they are apparently totally lost in less than four weeks if the supply is interrupted. The frequency of plant material and lithic particles increases from mouth to anus indicating that the retention time increases in the same way. Sand and plant material frequently co-occur in the intestine and in the stomach indicating that both are ingested together. Ground marble had negative effects on the growth of P. canaliculata probably due to the sharp edges and pointed ends of these particles. The availability of natural lithic particles (sand) had a positive effect on growth and also a synergic interaction with the availability of food. The growth efficiency was 25.2% higher when sand was available than when it was absent. These effects were more marked in juvenile females than in juvenile males. Our results indicate that growth rates may be underestimated under laboratory conditions if lithic particles are not supplied regularly and that their presence should be standardized to allow reliable comparisons between studies. Our results also indicate that the effects of food availability and plant palatability on the growth of P. canaliculata may be modulated by the presence of lithic particles and this may in turn affect the outcome of interactions between apple snails, other snails and macrophytes.","PeriodicalId":49895,"journal":{"name":"Malacologia","volume":"59 1","pages":"211 - 222"},"PeriodicalIF":1.3,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4002/040.059.0202","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70086239","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
X. Ovando, L. E. M. Lacerda, Roberta da Roza Dutra, S. Santos
Burnupia Walker, 1912, is a genus of freshwater limpet traditionally considered as belonging to the Ancylidae (Pilsbry & Bequaert, 1927; Hubendick, 1964; Brown, 1994; Lanzer, 1996; Hodgson & Healy, 1998), or included in the tribe Ancylini in the superfamily Planorboidea (Bouchet & Rocroi, 2005). However, its taxonomic position is controversial: based on similarity of radula morphology Pilsbry (1920) suggested a close relationship between Burnupia and South American Uncancylus Pilsbry, 1913. Brown (1965) placed this genus into the family Ferrissiidae, whereas Burch (1962) proposed a close relationship between Burnupia and Laevapex forming the subfamily Laevapecinae on the basis of the haploid chromosome number 17. Albrecht et al. (2004) tested whether the shell shape of Burnupia evolved independently and inferred its position within the Basommatophora. They concluded that the patelliform shell shape evolved at least three times in the Basommatophora, as previously proposed by Hubendick (1978), representing cases of convergent evolution. Currently, Burnupia is considered outside the Ancylinae according to Albrecht et al. (2007), who suggested a new “unnamed clade” for this genus. Burnupia not only appears to be distinct from the Ancylinae but also from all other representatives of the superfamily Planorboidea (Albrecht et al., 2007). In reference to the distribution of Burnupia, it has long been considered endemic to Africa (Basch, 1963; Wright, 1963; Hubendick, 1964; Albrecht et al., 2004), ranging from the highlands of Ethiopia and East Africa, southwards into Zaire, Angola and Zimbabwe, and widespread in South Africa (Walker, 1924; Hubendick, 1964). Subfossil MALACOLOGIA, 2016, 59(2): 333−339
Burnupia Walker, 1912年，是淡水帽贝的一个属，传统上被认为属于帽贝科(Pilsbry & Bequaert, 1927;Hubendick, 1964;布朗,1994;Lanzer, 1996;Hodgson & Healy, 1998)，或被纳入Planorboidea超家族中的Ancylini部落(Bouchet & Rocroi, 2005)。然而，其分类地位存在争议:基于radula形态学的相似性，Pilsbry(1920)提出Burnupia与南美洲Uncancylus Pilsbry(1913)关系密切。Brown(1965)将该属归入Ferrissiidae科，而Burch(1962)根据单倍体染色体编号17，提出Burnupia与la蒸发虫之间的密切关系，形成la蒸发虫亚科。Albrecht et al.(2004)测试了Burnupia的壳形是否独立进化，并推断了它在Basommatophora中的位置。他们的结论是，像Hubendick(1978)之前提出的那样，在Basommatophora中，髌状壳的形状至少进化了三次，代表了趋同进化的情况。目前，根据Albrecht等人(2007)的说法，Burnupia被认为是在Ancylinae之外，他们提出了这个属的一个新的“未命名分支”。Burnupia不仅与Ancylinae不同，而且与Planorboidea超家族的所有其他代表都不同(Albrecht et al.， 2007)。关于burupia的分布，它一直被认为是非洲的地方性疾病(Basch, 1963;赖特,1963;Hubendick, 1964;Albrecht et al.， 2004)，范围从埃塞俄比亚和东非的高地，向南进入扎伊尔、安哥拉和津巴布韦，并广泛分布于南非(Walker, 1924;Hubendick, 1964)。昆虫学报，2016,59(2):333−339
{"title":"Burnupia ingae Lanzer, 1991 (Gastropoda: Hygrophila): Contributions to the Knowledge on Its Morphology and First Records in Rio De Janeiro State, Brazil","authors":"X. Ovando, L. E. M. Lacerda, Roberta da Roza Dutra, S. Santos","doi":"10.4002/040.059.0211","DOIUrl":"https://doi.org/10.4002/040.059.0211","url":null,"abstract":"Burnupia Walker, 1912, is a genus of freshwater limpet traditionally considered as belonging to the Ancylidae (Pilsbry & Bequaert, 1927; Hubendick, 1964; Brown, 1994; Lanzer, 1996; Hodgson & Healy, 1998), or included in the tribe Ancylini in the superfamily Planorboidea (Bouchet & Rocroi, 2005). However, its taxonomic position is controversial: based on similarity of radula morphology Pilsbry (1920) suggested a close relationship between Burnupia and South American Uncancylus Pilsbry, 1913. Brown (1965) placed this genus into the family Ferrissiidae, whereas Burch (1962) proposed a close relationship between Burnupia and Laevapex forming the subfamily Laevapecinae on the basis of the haploid chromosome number 17. Albrecht et al. (2004) tested whether the shell shape of Burnupia evolved independently and inferred its position within the Basommatophora. They concluded that the patelliform shell shape evolved at least three times in the Basommatophora, as previously proposed by Hubendick (1978), representing cases of convergent evolution. Currently, Burnupia is considered outside the Ancylinae according to Albrecht et al. (2007), who suggested a new “unnamed clade” for this genus. Burnupia not only appears to be distinct from the Ancylinae but also from all other representatives of the superfamily Planorboidea (Albrecht et al., 2007). In reference to the distribution of Burnupia, it has long been considered endemic to Africa (Basch, 1963; Wright, 1963; Hubendick, 1964; Albrecht et al., 2004), ranging from the highlands of Ethiopia and East Africa, southwards into Zaire, Angola and Zimbabwe, and widespread in South Africa (Walker, 1924; Hubendick, 1964). Subfossil MALACOLOGIA, 2016, 59(2): 333−339","PeriodicalId":49895,"journal":{"name":"Malacologia","volume":"59 1","pages":"333 - 339"},"PeriodicalIF":1.3,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4002/040.059.0211","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70086486","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Helix pomatia Linnaeus, 1758, the Roman snail, is widely exploited for food in Europe. Over-exploitation has led to protective measures laid down in the European Union Habitats Directive (European Community Directive on the Conservation of Natural Habitats and of Wild Fauna and Flora (92/43/EEC). In Poland, the implementation of this directive has involved passive protection by means of closed seasons for collecting, minimum size limits and annual rotation of areas in which collecting is permitted (Dyduch-Falniowska et al., 2001). The size limit (minimum shell diameter of 30 mm) has not changed for several decades. Helix pomatia has relatively slow reproductive and maturation rates (Ligaszewski et al., 2014). Efforts have been made to improve these under controlled conditions (Jeppensen, 1976; Gomot, 1990; Chmielewski, 2005). In experiments at the National Research Institute of Animal Production in Balice, Poland, mature H. pomatia taken from the wild and kept in greenhouses reproduced successfully, producing large numbers of hatchlings both in autumn and after the winter hibernation (Ligaszewski et al., 2007). While rearing snails in such conditions over the whole of their life cycle (eggs to harvested adults) is expensive, the release of juveniles into apparently suitable habitats might increase the number of natural populations and serve to secure the snail’s future in the face of exploitation. This study thus set out to determine the fate of juveniles reared in greenhouses and released into a semi-natural, synanthropic site in which the snail was absent. A target area was modified to provide good starting conditions, and the growth rate and dispersal of the introduced juveniles studied over the period 2011–2015. In particular, the study aimed to MALACOLOGIA, 2016, 59(2): 341−346
Helix pomatia Linnaeus, 1758年，罗马蜗牛，在欧洲被广泛用作食物。过度开发导致了《欧洲联盟生境指令》(欧洲共同体关于保护自然生境和野生动植物的指令(92/43/EEC))规定的保护措施。在波兰，该指令的实施涉及通过闭季收集、最小尺寸限制和允许收集区域的年度轮换等方式进行被动保护(Dyduch-Falniowska等人，2001年)。尺寸限制(最小外壳直径为30毫米)几十年来没有改变。双螺旋鱼的繁殖和成熟速度相对较慢(Ligaszewski et al.， 2014)。已经努力在受控条件下改善这些(Jeppensen, 1976;Gomot, 1990;Chmielewski, 2005)。在波兰Balice国家动物生产研究所的实验中，从野外采集的成熟的pomatia在温室中繁殖成功，在秋季和冬季冬眠后都产生了大量的幼仔(Ligaszewski等人，2007)。虽然在蜗牛的整个生命周期(从卵到收获的成虫)中在这种条件下饲养蜗牛是昂贵的，但将幼螺释放到明显合适的栖息地可能会增加自然种群的数量，并在蜗牛面临剥削时为它们的未来提供保障。因此，这项研究开始确定在温室中饲养的幼螺的命运，并将其释放到半自然的、没有蜗牛的共生场所。研究了2011-2015年引种幼鱼的生长速率和扩散情况。《生物医学工程学报》，2016,59(2):341−346
{"title":"Observations on Growth Rates and Maturity in an Introduced Population of the Roman Snail (Helix pomatia Linnaeus, 1758) at a Semi-Natural Site with no Natural Population","authors":"M. Ligaszewski, P. Pol, I. Radkowska","doi":"10.4002/040.059.0212","DOIUrl":"https://doi.org/10.4002/040.059.0212","url":null,"abstract":"Helix pomatia Linnaeus, 1758, the Roman snail, is widely exploited for food in Europe. Over-exploitation has led to protective measures laid down in the European Union Habitats Directive (European Community Directive on the Conservation of Natural Habitats and of Wild Fauna and Flora (92/43/EEC). In Poland, the implementation of this directive has involved passive protection by means of closed seasons for collecting, minimum size limits and annual rotation of areas in which collecting is permitted (Dyduch-Falniowska et al., 2001). The size limit (minimum shell diameter of 30 mm) has not changed for several decades. Helix pomatia has relatively slow reproductive and maturation rates (Ligaszewski et al., 2014). Efforts have been made to improve these under controlled conditions (Jeppensen, 1976; Gomot, 1990; Chmielewski, 2005). In experiments at the National Research Institute of Animal Production in Balice, Poland, mature H. pomatia taken from the wild and kept in greenhouses reproduced successfully, producing large numbers of hatchlings both in autumn and after the winter hibernation (Ligaszewski et al., 2007). While rearing snails in such conditions over the whole of their life cycle (eggs to harvested adults) is expensive, the release of juveniles into apparently suitable habitats might increase the number of natural populations and serve to secure the snail’s future in the face of exploitation. This study thus set out to determine the fate of juveniles reared in greenhouses and released into a semi-natural, synanthropic site in which the snail was absent. A target area was modified to provide good starting conditions, and the growth rate and dispersal of the introduced juveniles studied over the period 2011–2015. In particular, the study aimed to MALACOLOGIA, 2016, 59(2): 341−346","PeriodicalId":49895,"journal":{"name":"Malacologia","volume":"59 1","pages":"341 - 346"},"PeriodicalIF":1.3,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4002/040.059.0212","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70086039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
ABSTRACT Physa acuta (Gastropoda: Heterobranchia: Physidae) is a freshwater snail commonly found in North American rivers, streams and ponds. Despite its widespread distribution across the United States, it is generally regarded as an invasive species. As a result, P. acuta receives no attention during conservation management inventories. However, data suggest that P. acuta may be a native to North America rather than to Europe, where it was first described. First, the fossil record in Europe lacks P. acuta, whereas North America is home to numerous fossils of members of the acuta species group. Second, breeding studies among P. acuta and North American taxa from the acuta species group show no evidence of pre- or postzygotic isolation. Third, investigations of reproductive anatomy between P. acuta and other nominal species of the acuta species group are indistinguishable, leading investigators to synonymize taxa. Finally, phylogenetic data do not support the distinction of P. acuta from its North American congeners of the same species group. Together, these data support our case that P. acuta is a North American native.
{"title":"Physa acuta Draparnaud, 1805 Should be Treated as a Native of North America, Not Europe","authors":"C. Lydeard, D. Campbell, Michelle Golz","doi":"10.4002/040.059.0213","DOIUrl":"https://doi.org/10.4002/040.059.0213","url":null,"abstract":"ABSTRACT Physa acuta (Gastropoda: Heterobranchia: Physidae) is a freshwater snail commonly found in North American rivers, streams and ponds. Despite its widespread distribution across the United States, it is generally regarded as an invasive species. As a result, P. acuta receives no attention during conservation management inventories. However, data suggest that P. acuta may be a native to North America rather than to Europe, where it was first described. First, the fossil record in Europe lacks P. acuta, whereas North America is home to numerous fossils of members of the acuta species group. Second, breeding studies among P. acuta and North American taxa from the acuta species group show no evidence of pre- or postzygotic isolation. Third, investigations of reproductive anatomy between P. acuta and other nominal species of the acuta species group are indistinguishable, leading investigators to synonymize taxa. Finally, phylogenetic data do not support the distinction of P. acuta from its North American congeners of the same species group. Together, these data support our case that P. acuta is a North American native.","PeriodicalId":49895,"journal":{"name":"Malacologia","volume":"59 1","pages":"347 - 350"},"PeriodicalIF":1.3,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4002/040.059.0213","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70086184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Y. Shao, X. Chai, Guo-qiang Xiao, Jiong-ming Zhang, Zhihua Lin, G. Liu
ABSTRACT The blood clam, Tegillarca granosa, is widely distributed along the coasts of the Indo-Pacific region, providing an excellent opportunity to study gene flow in sessile marine mollusks. In the present study, amplified fragment length polymorphism (AFLP) DNA markers were used to analyze the genetic structure of five blood clam populations. Genetic differentiation (Gst) and Nei's genetic distances between population pairs were found to range from 0.0245 to 0.0785 and 0.0398 to 0.1125, respectively. An AMOVA analysis showed that 89.09% of the genetic variation occurred within populations and only 10.92% occurred among populations, indicating a high degree of genetic homogeneity, probably due to considerable gene flow (average Nm = 7.1853) among populations. Cluster analysis using the unweighted pair group method average (UPGMA) showed that geographically closer populations were clustered, suggesting isolation by distance, which was further supported by a significant positive correlation between Gst and logit transformed geographic distance through a Mantel test and reduced major axis regression (r = 0.77, p < 0.05). The evident isolation by distance observed among blood clam populations along the Pacific coast of Asia is likely to be a consequence of both the passive larval dispersal carried by the South China Sea Warm Current and the genetic homogeneity caused by aquaculture-associated human activities.
{"title":"Population Genetic Structure of the Blood Clam, Tegillarca granosa, Along the Pacific Coast of Asia: Isolation by Distance in the Sea","authors":"Y. Shao, X. Chai, Guo-qiang Xiao, Jiong-ming Zhang, Zhihua Lin, G. Liu","doi":"10.4002/040.059.0208","DOIUrl":"https://doi.org/10.4002/040.059.0208","url":null,"abstract":"ABSTRACT The blood clam, Tegillarca granosa, is widely distributed along the coasts of the Indo-Pacific region, providing an excellent opportunity to study gene flow in sessile marine mollusks. In the present study, amplified fragment length polymorphism (AFLP) DNA markers were used to analyze the genetic structure of five blood clam populations. Genetic differentiation (Gst) and Nei's genetic distances between population pairs were found to range from 0.0245 to 0.0785 and 0.0398 to 0.1125, respectively. An AMOVA analysis showed that 89.09% of the genetic variation occurred within populations and only 10.92% occurred among populations, indicating a high degree of genetic homogeneity, probably due to considerable gene flow (average Nm = 7.1853) among populations. Cluster analysis using the unweighted pair group method average (UPGMA) showed that geographically closer populations were clustered, suggesting isolation by distance, which was further supported by a significant positive correlation between Gst and logit transformed geographic distance through a Mantel test and reduced major axis regression (r = 0.77, p < 0.05). The evident isolation by distance observed among blood clam populations along the Pacific coast of Asia is likely to be a consequence of both the passive larval dispersal carried by the South China Sea Warm Current and the genetic homogeneity caused by aquaculture-associated human activities.","PeriodicalId":49895,"journal":{"name":"Malacologia","volume":"59 1","pages":"303 - 312"},"PeriodicalIF":1.3,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4002/040.059.0208","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70086435","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
J. Byern, A. Kerbl, Marie-Therese Nödl, G. Bello, Y. Staedler, J. Schönenberger, N. Cyran
ABSTRACT The hatching of an embryo from its egg is a crucial point in its development. This is the moment that decides whether the animal will be able to emerge and survive or whether it will remain trapped and die. Cephalopods usually produce enzymes in a system of glands known as the Hoyle organ, which weakens the chorion and enables hatching. In addition to this chemical approach, four cephalopod genera develop a terminal spine to further support the hatching process. The presence of such a spine has been mentioned for the well-known cephalopod species Euprymna scolopes. However, little is known about either its structure or its cellular details. Our present results indicate that the spine consists purely of musculature, and no intermediate connective tissue was observed. No nerves were detected within the spine, although nerve fibers are present within the surrounding epithelium and dermal muscle layer, indicating that the spine stretching is controlled by this dermal musculature. Our data show that the spine of Euprymna is similar in its composition to those of the other three cephalopod genera in which a spine has evolved. However, we found morphological differences in the spine tip and in a collagenous layer located between the spine and the normal epithelium. It remains unclear why two completely different but synergetic systems for hatching, the glandular Hoyle organ and a spine, exist in some, but not all, cephalopod genera.
{"title":"Spine Formation as a Hatching Tool in Euprymna scolopes (Mollusca, Cephalopoda, Sepiolidae)","authors":"J. Byern, A. Kerbl, Marie-Therese Nödl, G. Bello, Y. Staedler, J. Schönenberger, N. Cyran","doi":"10.4002/040.059.0204","DOIUrl":"https://doi.org/10.4002/040.059.0204","url":null,"abstract":"ABSTRACT The hatching of an embryo from its egg is a crucial point in its development. This is the moment that decides whether the animal will be able to emerge and survive or whether it will remain trapped and die. Cephalopods usually produce enzymes in a system of glands known as the Hoyle organ, which weakens the chorion and enables hatching. In addition to this chemical approach, four cephalopod genera develop a terminal spine to further support the hatching process. The presence of such a spine has been mentioned for the well-known cephalopod species Euprymna scolopes. However, little is known about either its structure or its cellular details. Our present results indicate that the spine consists purely of musculature, and no intermediate connective tissue was observed. No nerves were detected within the spine, although nerve fibers are present within the surrounding epithelium and dermal muscle layer, indicating that the spine stretching is controlled by this dermal musculature. Our data show that the spine of Euprymna is similar in its composition to those of the other three cephalopod genera in which a spine has evolved. However, we found morphological differences in the spine tip and in a collagenous layer located between the spine and the normal epithelium. It remains unclear why two completely different but synergetic systems for hatching, the glandular Hoyle organ and a spine, exist in some, but not all, cephalopod genera.","PeriodicalId":49895,"journal":{"name":"Malacologia","volume":"59 1","pages":"231 - 238"},"PeriodicalIF":1.3,"publicationDate":"2016-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.4002/040.059.0204","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70086311","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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