Poecilia Sphenops Research Articles

TOXICITY OF ATRAZINE AND RELATED TO TESTICULAR, TISSUE DAMAGING ENZYME LEVELS IN POECILIA SPHENOPS

Objective: This study was designed to evaluate the toxic effects of Atrazine (ATZ) on the enzyme levels in Poecilia sphenops.Methods: The cytosolic testicular enzyme and tissue-damaging enzyme activity were measured in Poecilia sphenops was exposed to 3 sub-lethal concentrations (1.25, 2.5 and 5 mg/l) of atrazine for 100days and control was also maintained. The toxic effects of ATZ to Poecilia sphenops were assessed through testicular marker enzyme, tissue-damaging enzyme level.Results: The activities of testicular functional enzyme ALP, ACP, SDH, LDH, G6PDH and tissue-damaging the activities of glutamate oxaloacetic transaminase (GOT) and glutamate pyruvic transaminase (GPT) activity levels were altered in treated groups compared with that of the control.Conclusion: This study demonstrates that atrazine induces tissue damage in terms of enhanced enzyme activity and testicular enzyme activity in Poecilia sphenops. Atrazine has toxicity to the reproductive system in Poecilia sphenops.

Development and implementation of a fish counter by using an embedded system

The development and implementation of an instrument for the automatic counting of ornamental fish by using an embedded system, is introduced herein. The proposed instrument is tested with two marine species, the Guppies (Poecilia Reticulata) and Mollies (Poecilia Sphenops), under conditions of controlled lighting and specimens whose sizes vary from 0.5 to 2.3 cm. The counting is done by digital image processing obtaining an average accuracy up to 96.64% using different species of fishes and different sizes. The main contributions are the theoretical and experimental study to determine the aquarium background color and the algorithm of the proposed method implemented in a low cost and high performance embedded system, specifically in a Raspberry Pi 2 executing the free GNU Octave Scientific Programming Language, thus, allowing the counting instrument to be reliable, portable and easily migratory to different operating systems. The obtained results demonstrate that the proposed method is competitive with state-of-the-art ones.

Reproductive biology of the invasive species Pseudoxiphophorus bimaculatus and Poecilia sphenops in the Teuchitlán River, México

Summary Reproductive biology of invasive species is not often studied relative to the invasion process, although it may provide an accurate indicator of the invasion stage. We evaluated the reproductive biology of the exotic fish species Pseudoxiphophorus bimaculatus and Poecilia sphenops in the Teuchitlan River, Jalisco, Mexico by fertility, size at first maturity, sex ratio, gonad maturity stage, gonadosomatic index, condition factor, size-structure, and habitat. The reproductive variables were related to environmental characteristics using the non-metric analysis of multidimensional scaling. A total of 1374 specimens of P. bimaculatus and 571 of P. sphenops were captured by seine netting and electrofishing. Maximum fertility of P. bimaculatus was 15.99 ± 2.27 embryonated eggs and embryos and, for P. sphenops, 31.26 ± 4.17. Females predominated among P. bimaculatus, while in P. sphenops the sex ratio was ~1:1. We found mature female and male of P. bimaculatus in degraded sites and juveniles in the springs. Poecilia sphenops reproduced along the river. The establishment of both invasive species in the Teuchitlan River is evidence that they share the reproductive habitat with native fish species, and tend to spread and colonize new areas.

Metazoan parasites of freshwater ornamental fishes

This study aimed to characterize the metazoan parasitic fauna associated with freshwater farmed ornamental fish in Southern Brazil. Between July 2014 and January 2015, a total of 423 fish belonging to nine species were examined: Pterophylum scalare , Betta splendens , two varieties of Carassius auratus , Danio rerio , Xiphophorus helleri , two varieties of Xiphophorus maculatus , Poecilia sphenops , Tanichthys albonubes and Puntius sachsii . In each fish collection, the water quality parameters were measured. Specimens were obtained from three ornamental fish farms located in three micro-regions in the State of Santa Catarina (Araquari, Biguacu and Camboriu). Parasitological indexes were obtained after qualitative and quantitative parasitological analysis. Monogenean parasites, nematodes, and cestodes were found in all facilities. Nevertheless, nematodes and monogeneans presented 100% of prevalence in P. scalare from Araquari. From the analyzed species, P. scalare showed the highest parasite richness.

Protozoan parasites of freshwater ornamental fish

The ornamental fish aquaculture represents a consolidated market worldwide. In Brazil, the major volume of commercialized freshwater ornamental fish is originated from fish farms managed by small and midsized farmers. The aim of this study was to characterize the metazoan parasitic fauna associated with the main freshwater ornamental fish farmed in Southern Brazil. Between July 2014 and January 2015, 423 fishes belonging to nine freshwater species were examined: angelfish Pterophylum scalare , siamese fighting fish Betta splendens , telescope and comet goldfish Carassius auratus , zebrafish Danio rerio , blood red swordtail Xiphophorus helleri , caramel and wagtail platy fish Xiphophorus maculatus , black molly Poecilia sphenops , white cloud mountain minnow Tanichthys albonubes and goldfinned barb Puntius sachsii . Water quality was measured in fishponds from each facility. Specimens were obtained from three ornamental fish farms located in three micro-regions in the State of Santa Catarina (Biguacu, Camboriu e Joinville). Parasitological indexes were obtained after parasitological analysis of mucus, gills, and eyes. Trichodinids, Piscinoodinium pillulare , and Ichthyophthirius multifiliis were found in all fish farms analyzed. However, P. pillulare showed the greatest prevalence and mean intensity, compared to the other protozoa analyzed. 75% prevalence and mean intensity 57.5 were observed in the gills of P. scalare from fish farm Araquari. This study showed that fish farm Biguacu, was the facility presenting the greatest parasite diversity. P. scalare and C. auratus were the most parasitized fish species presenting the higher richness when compared to another species. These ornamental species are widely traded and require greater care in cultivation because it is essential to produce healthy fish with attractive features accepted by the market.

Impairment of Micronucleus and DNA in the 2-Chloro-4- Ethylamino-6- Isopropylamino-1, 3, 5-Triazine Exposed Poecilia Sphenops

Impairment of Micronucleus and DNA in the 2-Chloro-4- Ethylamino-6- Isopropylamino-1, 3, 5-Triazine Exposed Poecilia Sphenops

Colorful invasion in permissive Neotropical ecosystems: establishment of ornamental non-native poeciliids of the genera Poecilia/Xiphophorus (Cyprinodontiformes: Poeciliidae) and management alternatives

ABSTRACT Headwater creeks are environments susceptible to invasion by non-native fishes. We evaluated the reproduction of 22 populations of the non-native livebearers guppy Poecilia reticulata, black molly Poecilia sphenops, Yucatan molly Poecilia velifera, green swordtail Xiphophorus hellerii, southern platyfish Xiphophorus maculatus, and variable platyfish Xiphophorus variatus during an annual cycle in five headwater creeks located in the largest South American ornamental aquaculture center, Paraíba do Sul River basin, southeastern Brazil. With few exceptions, females of most species were found reproducing (stages 2, 3, 4) all year round in the creeks and gravid females of all species showed small sizes indicating stunting. Juveniles were frequent in all sites. The fecundity of the six poeciliids was always low in all periods. The sex ratio was biased for females in most species, both bimonthly as for the whole period. Water temperature, water level and rainfall were not significantly correlated with reproduction in any species. Therefore, most populations appeared well established. The pertinence of different management actions, such as devices to prevent fish escape, eradication with rotenone and research about negative effects on native species, is discussed in the light of current aquaculture practices in the region.

Green-synthesized silver nanoparticles using Psychotria nilgiriensis: toxicity against the dengue vector Aedes aegypti (Diptera: Culicidae) and impact on the predatory efficiency of the non-target organism Poecilia sphenops (Cyprinodontiformes: Poeciliidae)

Mosquitoes transmit serious diseases to humans and animals, causing millions of deaths every year. Effective insecticides of natural origin for eco-friendly vector control are a priority. In this study, silver nanoparticles (AgNPs) biosynthesized using as cheap Psychotria nilgiriensis leaf extract were tested on larvae and pupae of Aedes aegypti (Diptera: Culicidae). Biophysical characterization was carried out with UV–vis spectrophotometry, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Larvae were exposed to varying concentrations of aqueous extract of synthesized AgNPs for 24h. The maximum mortality was observed for green-synthesized AgNPs. Moreover, the combined treatment of leaf extract of P. nilgiriensis and AgNPs lowered the plant extract LC50 to 92.87, 115.27, 140.37, 169.30 and 212.55μg/ml. The effectiveness of green synthesized AgNPs was confirmed against eggs and adults of A. aegypti. Furthermore, we showed that the predatory efficiency of Poecilia sphenops on A. aegypti was not reduced after the exposure at sublethal doses of AgNPs. Predation in the control was 65% (larva I) and 49.62% (larva II). Predation against late-instar larvae was minimal. In AgNPs-treated environment (3ppm), predation was boosted to 90.25% (larva I) and 76.50% (larva II), respectively. Overall, P. nilgiriensis-synthesized AgNPs could be proposed at ultra-low doses to reduce larval population of dengue vectors enhancing predation rates of P. sphenops.

Collective epithelial cell sheet adhesion and migration on polyelectrolyte multilayers with uniform and gradients of compliance

Polyelectrolyte multilayers (PEMUs) are tunable thin films that could serve as coatings for biomedical implants. PEMUs built layer by layer with the polyanion poly(acrylic acid) (PAA) modified with a photosensitive 4-(2-hydroxyethoxy) benzophenone (PAABp) group and the polycation poly(allylamine hydrochloride) (PAH) are mechanically tunable by UV irradiation, which forms covalent bonds between the layers and increases PEMU stiffness. PAH-terminated PEMUs (PAH-PEMUs) that were uncrosslinked, UV-crosslinked to a uniform stiffness, or UV-crosslinked with an edge mask or through a neutral density optical gradient filter to form continuous compliance gradients were used to investigate how differences in PEMU stiffness affect the adhesion and migration of epithelial cell sheets from scales of the fish Poecilia sphenops (Black Molly) and Carassius auratus (Comet Goldfish). During the progressive collective cell migration, the edge cells (also known as ‘leader’ cells) in the sheets on softer uncrosslinked PEMUs and less crosslinked regions of the gradient formed more actin filaments and vinculin-containing adherens junctions and focal adhesions than formed in the sheet cells on stiffer PEMUs or glass. During sheet migration, the ratio of edge cell to internal cell (also known as ‘follower’ cells) motilities were greater on the softer PEMUs than on the stiffer PEMUs or glass, causing tension to develop across the sheet and periods of retraction, during which the edge cells lost adhesion to the substrate and regions of the sheet retracted toward the more adherent internal cell region. These retraction events were inhibited by the myosin II inhibitor Blebbistatin, which reduced the motility velocity ratios to those for sheets on the stiffer PEMUs. Blebbistatin also caused disassembly of actin filaments, reorganization of focal adhesions, increased cell spreading at the leading edge, as well as loss of edge cell-cell connections in epithelial cell sheets on all surfaces. Interestingly, cells throughout the interior region of the sheets on uncrosslinked PEMUs retained their actin and vinculin organization at adherens junctions after treatment with Blebbistatin. Like Blebbistatin, a Rho-kinase (ROCK) inhibitor, Y27632, promoted loss of cell-cell connections between edge cells, whereas a Rac1 inhibitor, NSC23766, primarily altered the lamellipodial protrusion in edge cells. Compliance gradient PAH-PEMUs promoted durotaxis of the cell sheets but not of individual keratocytes, demonstrating durotaxis, like plithotaxis, is an emergent property of cell sheet organization.

Effect of Formulated Feeds with Different Nutrient Levels on Growth and Reproductive Performance of Molly,Poecilia sphenops(Valenciennes)

Effect of Formulated Feeds with Different Nutrient Levels on Growth and Reproductive Performance of Molly,<i>Poecilia sphenops</i>(Valenciennes)

Reproductive biology of Poecilia sphenops Valenciennes, 1846 (Cyprinidontiformes: Poeciliidae) at the Emiliano Zapata Reservoir in Morelos, Mexico

ABSTRACT Poecilia sphenops is a native species recently recorded in the Balsas basin and the Amacuzac River in Morelos (Mexico), in which it is abundant and widely distributed. This study analyzed some aspects of the reproductive biology of Poecilia sphenops from the Emiliano Zapata Reservoir, in Central Mexico. Specimens were collected using a 20 m-long seine with a 5 mm mesh size, from January to December 2006. A total of 581 specimens were collected: 407 females (70.0%), 83 males (14.3%) and 91 individuals with no differentiated sex (15.7%). Fish ranged from 20 to 96 mm in total length and 0.01 to 13.07 g in body weight. The female to male sex ratio (4.9:1) deviated significantly from the unity (χ2= 214.2, p&lt;0.05). Monthly variations in gonadosomatic (GSI) and hepatosomatic (HSI) indexes and ovarian development stages showed that P. sphenops spawning season occurred between July and October, concurring with the rainy season. Another reproduction peak was registered in February. The largest length registered for males and females was 96 mm and 83 mm, respectively.

Fishes of the Grijalva River basin of Mexico and Guatemala

The Grijalva River basin is one of the largest hydrological systems in Central America. Despite its importance, an inventory of its ichthyofauna remains incomplete. We provide a systematic checklist of fishes recorded in the Grijalva River basin based on surveys performed from 2002 to 2015. The systematic list includes 92 species, belonging to 13 orders, 25 families and 50 genera, of which 83 species are native and nine are exotics. This checklist includes three range expansions (Profundulus hildebrandi, Poecilia sphenops and Paraneetroplus hartwegi). Fifteen species are endemic to the basin. The most diverse families are Cichlidae and Poeciliidae with 25 and 23 species, respectively. Secondary freshwater fish diversity is high with 65.1%, the remaining species are primary freshwater (13.3%) and peripheral (21.7%) fishes.

Complete mitochondrial genomes of two ornamental fishes

The complete mitochondrial genomes of two ornamental fishes, black molly (Poecilia sphenops) and blue gourami (Trichogaster trichopterus), were obtained by the traditional polymerase chain reaction (PCR)-based sequencing approach. The mitogenomes of P. sphenops and T. trichopterus are determined as 16,533 bp and 16,456 bp in length, respectively. Both the genomes include 22 transfer RNA genes, 13 protein-coding genes and 2 ribosomal RNA genes. Phylogenetic tree was constructed based on the complete mitogenomes of these two species and closely related 20 teleost species to assess their phylogenic relationship and evolution.

Assessing species boundaries using multilocus species delimitation in a morphologically conserved group of neotropical freshwater fishes, the Poecilia sphenops species complex (Poeciliidae).

Accurately delimiting species is fundamentally important for understanding species diversity and distributions and devising effective strategies to conserve biodiversity. However, species delimitation is problematic in many taxa, including ‘non-adaptive radiations’ containing morphologically cryptic lineages. Fortunately, coalescent-based species delimitation methods hold promise for objectively estimating species limits in such radiations, using multilocus genetic data. Using coalescent-based approaches, we delimit species and infer evolutionary relationships in a morphologically conserved group of Central American freshwater fishes, the Poecilia sphenops species complex. Phylogenetic analyses of multiple genetic markers (sequences of two mitochondrial DNA genes and five nuclear loci) from 10/15 species and genetic lineages recognized in the group support the P. sphenops species complex as monophyletic with respect to outgroups, with eight mitochondrial ‘major-lineages’ diverged by ≥2% pairwise genetic distances. From general mixed Yule-coalescent models, we discovered (conservatively) 10 species within our concatenated mitochondrial DNA dataset, 9 of which were strongly supported by subsequent multilocus Bayesian species delimitation and species tree analyses. Results suggested species-level diversity is underestimated or overestimated by at least ~15% in different lineages in the complex. Nonparametric statistics and coalescent simulations indicate genealogical discordance among our gene tree results has mainly derived from interspecific hybridization in the nuclear genome. However, mitochondrial DNA show little evidence for introgression, and our species delimitation results appear robust to effects of this process. Overall, our findings support the utility of combining multiple lines of genetic evidence and broad phylogeographical sampling to discover and validate species using coalescent-based methods. Our study also highlights the importance of testing for hybridization versus incomplete lineage sorting, which aids inference of not only species limits but also evolutionary processes influencing genetic diversity.

Jaw Angle Modulation in Response to Different Feeding Scenarios inPoecilia sphenops

Abstract The molly (Poecilia sphenops) has an unusual feeding mechanism among fishes in that its jaw is essentially “doublejointed”. They possess an extra joint within the lower jaw, or mandible, called an Intramandibular Joint (IMJ). Because of this joint, these fish are capable of opening their mouths to extreme angles. We wanted to understand how this mechanism functions during feeding and if the joint angles could be actively altered by the fish in different feeding situations. We asked specifically if there was a difference in the gape angle (the angle formed by the tip of upper jaw, the jaw joint, and the tip of the lower jaw) and intramandibular joint angle when offered food in the water column versus on the substrate, as well as with different food types in the water column. Feeding events were captured using high-speed video and the resulting footage analyzed using the software Image J. The average gape angle produced during midwater feedings was significantly larger than that produced during ben...

The prevalence of non-indigenous parasitic copepod (Neoergasilus japonicus) spreads with fishes of pet trade in Kerman, Iran.

Ergasilids are copepods living in the river mouth of freshwaters and parasitic on Teleost fish family in both natural and artificial environments. So far, 5 species of the copepod have been discovered that belong to the genus Neoergasilus. This copepod is most likely to be disseminated through aquarium trades, aquaculture and over-nutrition, or construction of sand carrying water. The females of Ergasilidae are external parasites attaching to the anal and dorsal fins and sometimes to gills and nasal cavities of fish living in freshwaters. In total, 552 pieces of ornamental fish (301 males and 251 females) with length of 5-10cm from fish (Poecilia sphenops) species (Singapore, Sandy, Dirigible and scorpion's tail) were collected from ornamental fish stores in different regions of Kerman, Iran during 1year in 2012-2013 and tested in order to examine Neoergasilus japonicus infestation. From 188 adult females Neoergasilus japonicus specimens recorded on the fish host, 8 (4.26%) were on the anal, 120 (63.83%) on the dorsal, 10 (5.32%), on the pectoral, 45 (23.94%) on the pelvic, and 5 (2.66%) on the caudal fins. In this study, the prevalence of parasitic copepod infestation from Dec. to May was 26.31, 27.69, 26.19, 14, 18.75, and 7.5%, respectively. There was no significant difference between infestation prevalence in indigenous and non-native fishes (P=0.18). There were significant differences between different months of year in the prevalence and intensity of Neoergasilus japonicas (P<0.05). There was significant difference between frequency distribution of Neoergasilus Japonicus infestation in different organs (P<0.05). The male fish infestation (16.3%) was significantly higher than female fish infestation (5.6%) (P<0.05). Considering that the Neoergasilus japonicus was first observed in native and nonnative ornamental fish in Kerman, further studies should be conducted on the copepod infestation in stores supplying ornamental fish in other parts of Iran to make more accurate judgments.

Ichthyofaunal Survey in Selected Freshwater Habitats in Camarines Sur, Philippines

Ichthyofaunal surveys were conducted in five aquatic habitats (Lake Bato, Agos River, Bagacay Falls, Lake Baao-Bula, and Pawili River) in Camarines Sur, Philippines to evaluate the diversity and distribution of freshwater fish assemblages. The study collected a total of 8,184 individuals comprising 29 species, 22 genera, and belonging to 14 families. The three most abundant groups, in order of importance were cichlids, cyprinids, and poeciliids. Overall, four fish species comprised 52% of the total abundance. These were Oreochromis niloticus (Cichlidae), Glossogobius giuris (Gobiidae), Poecilia sphenops (Poeciliidae), and P. reticulata (Poeciliidae). In terms of richness, Gobiidae are the most dominant fish group (8 species). Except in Bagacay, Shannon-Weiner diversity indices ranged from 2.04 to 2.07. Relatively high evenness indices and low dominance values were computed in the four sites. Fish densities were significantly different among the five studied areas (Friedman test: χ 2 = 43.06, P< 0.01). Bray-Curtis similarity analysis on abundance data clearly showed two clusters. Fairly high levels of similarity (49.61%— 62.81%) were observed in Baao, Bato, Pawili, and Agos, whereas Bagacay was apparently deviated from the rest. Environmental variables are fluctuating but still within the tolerable level. The survey revealed the established feral populations of introduced fish species in the four representative sites. Aquaculture operations and domestic effluents were observed to be the main key drivers of fish faunal change in the lake and stream habitats. Keywords: Bato, Camarines Sur, diversity, fish survey, Gobiidae, native species

Influence of Triazine Herbicide Exposure on Guppies (Poecilia sphenops) Aromatase Activities, Altered Sex Steroid Concentration and Vitellogenin Induction.

Atrazine, a herbicide is one the most toxic and sustaining pollutants in aquatic environment. It is detectable in surface water and in underground sources of drinking water. Many studies indicate that atrazine might be a potent endocrine disrupting xenobiotic. There are limited studies have revealed that the effects of atrazine on sex steroids hormones, vitellogenin and induction of aromatase, gonadosomatic index and hepatosomatic index. In this study, juvenile Poecilia sphenops fish was exposed to three different (0.83, 1.25 and 2.5 ppm) concentration of atrazine for 100 d. Changes in plasma and gonadal content and concentrations of sex steroids and vitellogenin protein in poecilia sphenops under laboratory conditions were assessed. The low level of the atrazine show estrogenic effect in males, as determined by a shortage of testosterone induction. Present study suggests that low induction of plasma vitellogenin and aromatase in male fish become suitable biomarkers of exposure to estrogenic chemicals.

Using cytogenetic analysis RAPD in determination of genetic variations among four species of ornamental fishes of family: Poecilidae (Order: Cyprinodontiform)

The karyological and molecular analysis of four fresh water fish species of Family: Poecilidae and their genetic relationships have been studied. Xiphophorus maculates and Xiphophorus hellerii have the same diploid chromosome number 2n=48, but they were different in their karyotypes. Poecilia sphenops and Poecilia reticulata have the same diploid chromosome number 2n=46 and the same fundamental number FN=46, also the same karyotype one group of acrocentric chromosomes. Nine RAPD primers, showed monomorphic bands, were used for the construction of the dendrogram and a similarity matrix. A total of 65 bands were obtained; 39 of them were monomorphic bands. Similarity values among the studied samples ranged from 21% to 38%. High similarity value was obtained between Xiphophorus maculates and Xiphophorus hellerii. (38%) and the low similarity values were obtained between Xiphophorus hellerii and Poecilia reticulata (21%). The cluster analysis clearly differentiated Xiphophorus maculates and Xiphophorus hellerii from Poecilia sphenops and Poecilia reticulata. RAPD analysis confirmed that the four species under study are genetically different from each other. These cytogenetic data obtained can be applied for further studies in cytotaxonomy and evolutionary relationships of fishes.

Phyllodistomum spinopapillatum sp. nov. (Digenea: Gorgoderidae), from the Oaxaca killifish Profundulus balsanus (Osteichthyes: Profundulidae) in Mexico, with new host and locality records of P. inecoli: Morphology, ultrastructure and molecular evidence.

Phyllodistomum spinopapillatum sp. nov. is described from the urinary bladder of the Oaxaca killifish, Profundulus balsanus Ahl (Profundulidae) in Rio Pueblo Viejo and Rio Santa Cruz, Oaxaca, southwestern Mexico. The new species is described based on evidence gathered from morphology, scanning electron microscopy (SEM), and partial sequences of the 28S rRNA gene. Diagnostic characters of the new species of Phyllodistomum Braun 1899 are the presence of spines on the entire body surface and having a ventral sucker almost half the size of oral sucker. The new species possess a large number of dome-like papillae on the body surface with scattered distribution along the hindbody, and these papillae are characteristically spinulated. Phyllodistomum spinopapillatum sp. nov. most closely resembles P. inecoli Razo-Mendivil, Perez-Ponce de Leon and Rubio- Godoy, 2013, a parasite of the twospot livebearer Pseudoxiphophorus bimaculatus (Heckel) from Veracruz, in the Atlantic slope of Mexico. In addition to the new species, specimens of P. inecoli were also found parasitising the urinary bladder of cyprinodontiforms such as the Mexican molly Poecilia sphenops Valencienes in a pond at Santa Maria Coyotepec, and in Profundulus sp. in Rio Templo, both in Oaxaca, and in the Porthole livebearer Poeciliopsis gracilis (Heckel) in Rio San Juan, as well as in Profundulus punctatus (Gunter) from Rio Nueva Francia, both in Chiapas. The distribution and host range of P. inecoli is extended to freshwaters of the Pacific slope of Mexico, and to other cyprynodontiforms.