We report here the results of four scientific expeditions in the Nepalese Himalayas, that were ca... more We report here the results of four scientific expeditions in the Nepalese Himalayas, that were carried out in the period 1992-1997, in the framework of a Project on "The Long Distance transport of micro-pollutants" . Logistic and technical support was given by a laboratory located at 5050 m a.s.l. Phytoplankton, zooplankton and macrozoobenthos were collected from a total of 28 lakes, at altitudes between 4532 and 5580 m a.s.l. Very few phytoplankton species were found in high numbers. As expected, no phytoplankton communities nor algal species characteristic of high altitude sites were found, being in general high mountain environments characterized by a rarefaction of the communities with respect to low altitude sites. We found low chlorophyll-a and biomass values, with a high contribution by small species. Data from the intensive sampling of Lake Piramide Inferiore in late summer 1993, suggest that net phytoplankton was at that time of the year already in a declining phase. An intense growth had probably occurred earlier in the season, possibly just after the icemelting. We identified 9 species of Crustacea and 8 of Rotifera from the 26 lakes sampled for zooplankton. The most widely distributed was an endemic, well-known diaptomid of the palaeoarctic genus Arctodiaptomus (Arctodiaptomus jurisovitchi). Daphniidae were represented by the dark-brown Daphnia tibetana and Simocephalus vetulus, and a pale Daphnia of the longispina group. A melanic Chydorus sphaericus was also widely distributed, with both parthenogenetic and ephippial females, as well as males. Rotifers were found in high numbers in lakes of the western side of the Region, with both genuine high mountain species, (Hexarthra bulgarica var. nepalensis, Filinia maior), as well as the colonial Conochilus unicornis, never reported before. Anostraca, recovered from the littorals of two lakes, were identified as Branchinecta orientalis. We also counted the thecamoebian species occasionally found in some zooplankton samples. Three chironomid genera (Pseudodiamesa, Orthocladius and Micropsectra) and oligochaetes dominated the communities of the nine examined lakes. We found two species of Diamesinae, already reported from the Region, and two larval forms of Micropsectra. All the genera of Orthocladiinae previously recorded in the Region, were present, namely, larvae and pupae of Cricotopus, as well as Acricotopus and Pseudosmittia. In most lakes Oligochaeta were represented by Lumbriculidae. Enchytraeidae and a Tubificid species, probably belonging to Rhyacodrilus cf. stephensoni, were also recovered from the littoral of some lakes.
Ecological studies onArtemia are still sparse, particularly in the Mediterranean area. The paper ... more Ecological studies onArtemia are still sparse, particularly in the Mediterranean area. The paper provides information on the main life-history traits of a bisexualArtemia strain in solar saltworks at Sant'Antioco, in the Province of Cagliari (southern Sardinia, Italy). Data on age class composition, reproductive mode and status, fecundity and other features are discussed in relation to environmental conditions and compared with previous studies.
Studies on Large Branchiopod Biology and Conservation, 1997
... of total FAME) and quantitative (lipids mg/g dw) fatty acids composition of feeds and fairy s... more ... of total FAME) and quantitative (lipids mg/g dw) fatty acids composition of feeds and fairy shrimp species fed on alga (S. capricornutum), baker's yeast (S. cerevisiae) and enriched yeast (Lansy PZ). Alga diet Baker's yeast diet Enriched yeast diet Fatty acids Feed BP CK Feed BP ...
Randomly amplified polymorphic DNA (RAPD) was used to detect intra-clutch genetic differences of ... more Randomly amplified polymorphic DNA (RAPD) was used to detect intra-clutch genetic differences of the anostracan Chirocephalus diaphanus Prévost, 1803. Thirty primers were tested on 130 nauplii from three different clutches. Two primers produced five repeatable and well-defined amplification products, that were used as genotype markers. Nauplii hatched after three successive dehydration and rehydration cycles. Consistent genetic differentiation was observed among nauplii from the same clutch. Significant association between presence or absence of three polymorphic amplification products and hatching after different stimuli was observed. These results suggest that RAPD markers might be related to the difference in nauplii hatching and provide reasonable support to the hypothesis that the source of the observed variation in hatching phenology are genetic as well as epigenetic.
Studies on Large Branchiopod Biology and Conservation, 1997
Wild populations of five Chirocephalus species from Italy were tested for their fatty acid profil... more Wild populations of five Chirocephalus species from Italy were tested for their fatty acid profiles, particularly essential fatty acids (EFA) in order to obtain information on species differences. Chirocephalus diaphanus, C. kerkyrensis and C. salinus were from temporary plain pools, whereas C. ruffoi and C. marchesonii came from a mountain pool and an astatic high altitude lake. Statistical comparisons of the results obtained revealed significant ( 0.05) qualitative and quantitative differences among the species studied. Besides genetic make-up, other factors are presumably involved in these differences. Among these, environmental stability, and hence food quality and quantity, may play a major role, an hypothesis supported by previous findings regarding the possibility of manipulating fairy shrimp fatty acid patterns by using different diets. Further investigation is needed, however, on the fatty acid composition of the food resources from different habitats in relation to the fairy shrimp inhabitants.
Life histories of two populations of Tanymastix stagnalisfrom sites in central Italy, differing i... more Life histories of two populations of Tanymastix stagnalisfrom sites in central Italy, differing in climate and altitude above sea level, were compared to obtain information on the tolerance limits of this species.
We report the finding of three anostracan species, Chirocephalus skorikowi , Branchinecta orienta... more We report the finding of three anostracan species, Chirocephalus skorikowi , Branchinecta orientalis Sars, 1901 and Branchinella spinosa. Milne-Edwards, 1840 in different localities in northwestern Iran. C. skorikowi was recorded in a lake at an elevation of 2400 m, whereas B. orientalis was found in a pond at 1280 m a.s.l. Coexisting B. spinosa and B. orientalis were collected in a pool close to the town of Tabriz, formerly indicated by as Estakr Chah, presently named EalGoli. Unlike Brehm (1954), we did not find Streptocephalus in the area of Tabriz.
Some temporary pools in the Pollino National Park (1780–1900 m a.s.l) are inhabited by Chirocepha... more Some temporary pools in the Pollino National Park (1780–1900 m a.s.l) are inhabited by Chirocephalus ruffoi Cottarelli & Mura, 1984, an endemic Italian anostracan. These pools predictably fill by snowmelting in spring, but the timing and the duration of their flooding is unpredictable. Depending on climate, in some years, they also erratically fill by unpredictable rainfall in autumn. Field monitoring and continuous temperature data recordings were performed, in order to define habitat characteristics and related adaptive strategies of the resident population.
Patterns of sequence divergence in about 1 kb of mitochondrial DNA coding for two genes (16s rRNA... more Patterns of sequence divergence in about 1 kb of mitochondrial DNA coding for two genes (16s rRNA and cytochrome oxidase I, COI) were analysed in 13 populations of the fairy shrimp Tanymastix stagnalis from Norway, Germany, France, Italy (northern and central Italy plus insular populations from Sardinia and the Tuscan Archipelago) and Spain, and in one presumed population of Tanymastix stellae from Corsica. The latter species was originally known only from a single locality in Sardinia, which has been destroyed by urbanization; the Corsican population was referred to T. stellae by some French authors on the basis of the collection of several cysts from mud. mtDNA data revealed a very low level of genetic divergence between the presumed population of T. stellae and the other T. stagnalis populations included in the study. Our genetic findings do not support the presence of T. stellae in Corsica and are in line with previous SEM studies revealing that all species belonging to the genus Tanymastix produce cysts with identical morphology. The results indicate complex phylogeographic relationships and pronounced genetic differentiation among T. stagnalis populations. The islands of Corsica and Sardinia on the one hand and the island of Capraia (Tuscan Archipelago) on the other were probably colonized independently at different times. Genetic relationships among continental populations do not follow a clear geographical trend, indicating that geographical distance is not the main force shaping the pattern of genetic structuring of the species. Stochastic factors such as multiple and independent founder events probably contributed to the striking pattern of genetic differentiation along with subsequent local adaptation. These results agree with previously published molecular work on several groups of aquatic organisms and further support the high potential for dispersal-low gene flow paradox shown by a large array of animals living in lentic habitats.
Journal of Zoological Systematics and Evolutionary Research, 2003
This study analysed the levels of genetic differentiation within and among the six Italian specie... more This study analysed the levels of genetic differentiation within and among the six Italian species of the fairy shrimp genus Chirocephalus by analysing electrophoretic polymorphisms at 22 enzymatic loci and by sequencing a 665-bp fragment of the mitochondrial gene encoding for subunit I of cytochrome oxidase. The allozyme data revealed different levels of intra-specific differentiation; mean h estimates were low in Chirocephalus salinus, higher and comparable in C. diaphanus and C. kerkyrensis, while C. ruffoi was the most genetically structured species. At the inter-specific level, C. marchesonii was the most differentiated species, both for allozymes and mtDNA. Phylogenetic relationships deduced from allozymes and mtDNA were not always consistent with each other. This highlights the differences in performance of the two classes of molecular markers and the need of different independent strategies of data analysis to search for possible incongruence. Neither allozymes nor mtDNA supported monophyly of the diaphanus-group, previously recognized on the basis of the morphology of appendages (antennae and penes). In contrast the molecular results were consistent with the great heterogeneity in resting egg morphology among representatives of the diaphanus-group.
In 2001 nine temporary pools of the northern Apennines (Italy) were visited on 13 occasions durin... more In 2001 nine temporary pools of the northern Apennines (Italy) were visited on 13 occasions during the ice-free season (May to October). The aims of this research were to define the relationships between hydroperiod and other environmental variables and the zooplankton. In total, 49 zooplankton taxa were identified: 36 rotifers, 5 cladocerans, 6 copepods and 2 anostracans. Our results indicate that hydroperiod is a major determinant affecting zooplankton species richness. The highest number of taxa was found in the pond having the longest duration. Distinctive species assemblages were observed in different habitat types: pools with the shortest hydroperiod were characterised by organisms with brief life cycles (e.g. rotifers) and/or typical of temporary habitat (e.g. anostracans). Of the physical and chemical characteristics, pH and chlorophyll-a appeared to have the largest influence on zooplankton distribution in the studied pools. Internat. Rev. Hydrobiol. 90 2005 4 358-375
Doubts have been raised about the use of morphological characters as criteria for species separat... more Doubts have been raised about the use of morphological characters as criteria for species separation within the genus Artemia because of their relative validity. The characters considered to date, i.e. morphology of the frontal knobs of the male and the presence/absence of a spine-like projection on the basal part of the penis, are only partly efficacious, since they allow us to reliably distinguish only the Mediterranean species, Artemia salina, from the other bisexual species. While A. salina is characterized by subconical frontal knobs and the absence of the spine-like projection, the other species present subspherical frontal knobs and the spine-like projections. There is no information about the aspect of the frontal knobs in the Asian bisexual species. The aim of the present study is to clarify the situation by means of SEM observations of characters not considered in detail (ornamentation of the apical part of the spine-like projections) and by examination of the frontal knobs in the Asian species, which were not described at the time of the first studies.
We report here the results of four scientific expeditions in the Nepalese Himalayas, that were ca... more We report here the results of four scientific expeditions in the Nepalese Himalayas, that were carried out in the period 1992-1997, in the framework of a Project on "The Long Distance transport of micro-pollutants" . Logistic and technical support was given by a laboratory located at 5050 m a.s.l. Phytoplankton, zooplankton and macrozoobenthos were collected from a total of 28 lakes, at altitudes between 4532 and 5580 m a.s.l. Very few phytoplankton species were found in high numbers. As expected, no phytoplankton communities nor algal species characteristic of high altitude sites were found, being in general high mountain environments characterized by a rarefaction of the communities with respect to low altitude sites. We found low chlorophyll-a and biomass values, with a high contribution by small species. Data from the intensive sampling of Lake Piramide Inferiore in late summer 1993, suggest that net phytoplankton was at that time of the year already in a declining phase. An intense growth had probably occurred earlier in the season, possibly just after the icemelting. We identified 9 species of Crustacea and 8 of Rotifera from the 26 lakes sampled for zooplankton. The most widely distributed was an endemic, well-known diaptomid of the palaeoarctic genus Arctodiaptomus (Arctodiaptomus jurisovitchi). Daphniidae were represented by the dark-brown Daphnia tibetana and Simocephalus vetulus, and a pale Daphnia of the longispina group. A melanic Chydorus sphaericus was also widely distributed, with both parthenogenetic and ephippial females, as well as males. Rotifers were found in high numbers in lakes of the western side of the Region, with both genuine high mountain species, (Hexarthra bulgarica var. nepalensis, Filinia maior), as well as the colonial Conochilus unicornis, never reported before. Anostraca, recovered from the littorals of two lakes, were identified as Branchinecta orientalis. We also counted the thecamoebian species occasionally found in some zooplankton samples. Three chironomid genera (Pseudodiamesa, Orthocladius and Micropsectra) and oligochaetes dominated the communities of the nine examined lakes. We found two species of Diamesinae, already reported from the Region, and two larval forms of Micropsectra. All the genera of Orthocladiinae previously recorded in the Region, were present, namely, larvae and pupae of Cricotopus, as well as Acricotopus and Pseudosmittia. In most lakes Oligochaeta were represented by Lumbriculidae. Enchytraeidae and a Tubificid species, probably belonging to Rhyacodrilus cf. stephensoni, were also recovered from the littoral of some lakes.
Ecological studies onArtemia are still sparse, particularly in the Mediterranean area. The paper ... more Ecological studies onArtemia are still sparse, particularly in the Mediterranean area. The paper provides information on the main life-history traits of a bisexualArtemia strain in solar saltworks at Sant'Antioco, in the Province of Cagliari (southern Sardinia, Italy). Data on age class composition, reproductive mode and status, fecundity and other features are discussed in relation to environmental conditions and compared with previous studies.
Studies on Large Branchiopod Biology and Conservation, 1997
... of total FAME) and quantitative (lipids mg/g dw) fatty acids composition of feeds and fairy s... more ... of total FAME) and quantitative (lipids mg/g dw) fatty acids composition of feeds and fairy shrimp species fed on alga (S. capricornutum), baker's yeast (S. cerevisiae) and enriched yeast (Lansy PZ). Alga diet Baker's yeast diet Enriched yeast diet Fatty acids Feed BP CK Feed BP ...
Randomly amplified polymorphic DNA (RAPD) was used to detect intra-clutch genetic differences of ... more Randomly amplified polymorphic DNA (RAPD) was used to detect intra-clutch genetic differences of the anostracan Chirocephalus diaphanus Prévost, 1803. Thirty primers were tested on 130 nauplii from three different clutches. Two primers produced five repeatable and well-defined amplification products, that were used as genotype markers. Nauplii hatched after three successive dehydration and rehydration cycles. Consistent genetic differentiation was observed among nauplii from the same clutch. Significant association between presence or absence of three polymorphic amplification products and hatching after different stimuli was observed. These results suggest that RAPD markers might be related to the difference in nauplii hatching and provide reasonable support to the hypothesis that the source of the observed variation in hatching phenology are genetic as well as epigenetic.
Studies on Large Branchiopod Biology and Conservation, 1997
Wild populations of five Chirocephalus species from Italy were tested for their fatty acid profil... more Wild populations of five Chirocephalus species from Italy were tested for their fatty acid profiles, particularly essential fatty acids (EFA) in order to obtain information on species differences. Chirocephalus diaphanus, C. kerkyrensis and C. salinus were from temporary plain pools, whereas C. ruffoi and C. marchesonii came from a mountain pool and an astatic high altitude lake. Statistical comparisons of the results obtained revealed significant ( 0.05) qualitative and quantitative differences among the species studied. Besides genetic make-up, other factors are presumably involved in these differences. Among these, environmental stability, and hence food quality and quantity, may play a major role, an hypothesis supported by previous findings regarding the possibility of manipulating fairy shrimp fatty acid patterns by using different diets. Further investigation is needed, however, on the fatty acid composition of the food resources from different habitats in relation to the fairy shrimp inhabitants.
Life histories of two populations of Tanymastix stagnalisfrom sites in central Italy, differing i... more Life histories of two populations of Tanymastix stagnalisfrom sites in central Italy, differing in climate and altitude above sea level, were compared to obtain information on the tolerance limits of this species.
We report the finding of three anostracan species, Chirocephalus skorikowi , Branchinecta orienta... more We report the finding of three anostracan species, Chirocephalus skorikowi , Branchinecta orientalis Sars, 1901 and Branchinella spinosa. Milne-Edwards, 1840 in different localities in northwestern Iran. C. skorikowi was recorded in a lake at an elevation of 2400 m, whereas B. orientalis was found in a pond at 1280 m a.s.l. Coexisting B. spinosa and B. orientalis were collected in a pool close to the town of Tabriz, formerly indicated by as Estakr Chah, presently named EalGoli. Unlike Brehm (1954), we did not find Streptocephalus in the area of Tabriz.
Some temporary pools in the Pollino National Park (1780–1900 m a.s.l) are inhabited by Chirocepha... more Some temporary pools in the Pollino National Park (1780–1900 m a.s.l) are inhabited by Chirocephalus ruffoi Cottarelli & Mura, 1984, an endemic Italian anostracan. These pools predictably fill by snowmelting in spring, but the timing and the duration of their flooding is unpredictable. Depending on climate, in some years, they also erratically fill by unpredictable rainfall in autumn. Field monitoring and continuous temperature data recordings were performed, in order to define habitat characteristics and related adaptive strategies of the resident population.
Patterns of sequence divergence in about 1 kb of mitochondrial DNA coding for two genes (16s rRNA... more Patterns of sequence divergence in about 1 kb of mitochondrial DNA coding for two genes (16s rRNA and cytochrome oxidase I, COI) were analysed in 13 populations of the fairy shrimp Tanymastix stagnalis from Norway, Germany, France, Italy (northern and central Italy plus insular populations from Sardinia and the Tuscan Archipelago) and Spain, and in one presumed population of Tanymastix stellae from Corsica. The latter species was originally known only from a single locality in Sardinia, which has been destroyed by urbanization; the Corsican population was referred to T. stellae by some French authors on the basis of the collection of several cysts from mud. mtDNA data revealed a very low level of genetic divergence between the presumed population of T. stellae and the other T. stagnalis populations included in the study. Our genetic findings do not support the presence of T. stellae in Corsica and are in line with previous SEM studies revealing that all species belonging to the genus Tanymastix produce cysts with identical morphology. The results indicate complex phylogeographic relationships and pronounced genetic differentiation among T. stagnalis populations. The islands of Corsica and Sardinia on the one hand and the island of Capraia (Tuscan Archipelago) on the other were probably colonized independently at different times. Genetic relationships among continental populations do not follow a clear geographical trend, indicating that geographical distance is not the main force shaping the pattern of genetic structuring of the species. Stochastic factors such as multiple and independent founder events probably contributed to the striking pattern of genetic differentiation along with subsequent local adaptation. These results agree with previously published molecular work on several groups of aquatic organisms and further support the high potential for dispersal-low gene flow paradox shown by a large array of animals living in lentic habitats.
Journal of Zoological Systematics and Evolutionary Research, 2003
This study analysed the levels of genetic differentiation within and among the six Italian specie... more This study analysed the levels of genetic differentiation within and among the six Italian species of the fairy shrimp genus Chirocephalus by analysing electrophoretic polymorphisms at 22 enzymatic loci and by sequencing a 665-bp fragment of the mitochondrial gene encoding for subunit I of cytochrome oxidase. The allozyme data revealed different levels of intra-specific differentiation; mean h estimates were low in Chirocephalus salinus, higher and comparable in C. diaphanus and C. kerkyrensis, while C. ruffoi was the most genetically structured species. At the inter-specific level, C. marchesonii was the most differentiated species, both for allozymes and mtDNA. Phylogenetic relationships deduced from allozymes and mtDNA were not always consistent with each other. This highlights the differences in performance of the two classes of molecular markers and the need of different independent strategies of data analysis to search for possible incongruence. Neither allozymes nor mtDNA supported monophyly of the diaphanus-group, previously recognized on the basis of the morphology of appendages (antennae and penes). In contrast the molecular results were consistent with the great heterogeneity in resting egg morphology among representatives of the diaphanus-group.
In 2001 nine temporary pools of the northern Apennines (Italy) were visited on 13 occasions durin... more In 2001 nine temporary pools of the northern Apennines (Italy) were visited on 13 occasions during the ice-free season (May to October). The aims of this research were to define the relationships between hydroperiod and other environmental variables and the zooplankton. In total, 49 zooplankton taxa were identified: 36 rotifers, 5 cladocerans, 6 copepods and 2 anostracans. Our results indicate that hydroperiod is a major determinant affecting zooplankton species richness. The highest number of taxa was found in the pond having the longest duration. Distinctive species assemblages were observed in different habitat types: pools with the shortest hydroperiod were characterised by organisms with brief life cycles (e.g. rotifers) and/or typical of temporary habitat (e.g. anostracans). Of the physical and chemical characteristics, pH and chlorophyll-a appeared to have the largest influence on zooplankton distribution in the studied pools. Internat. Rev. Hydrobiol. 90 2005 4 358-375
Doubts have been raised about the use of morphological characters as criteria for species separat... more Doubts have been raised about the use of morphological characters as criteria for species separation within the genus Artemia because of their relative validity. The characters considered to date, i.e. morphology of the frontal knobs of the male and the presence/absence of a spine-like projection on the basal part of the penis, are only partly efficacious, since they allow us to reliably distinguish only the Mediterranean species, Artemia salina, from the other bisexual species. While A. salina is characterized by subconical frontal knobs and the absence of the spine-like projection, the other species present subspherical frontal knobs and the spine-like projections. There is no information about the aspect of the frontal knobs in the Asian bisexual species. The aim of the present study is to clarify the situation by means of SEM observations of characters not considered in detail (ornamentation of the apical part of the spine-like projections) and by examination of the frontal knobs in the Asian species, which were not described at the time of the first studies.
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Papers by Graziella Mura