Morphology of testate amoeba Difflugia australis (Playfair, 1918) Gautier-Lièvre et Thomas, 1958 from a subtropical reservoir (southeast China)

Zootaxa ◽  
2020 ◽  
Vol 4890 (1) ◽  
pp. 97-108
Author(s):  
JEAN CLAUDE NDAYISHIMIYE ◽  
PASCALINE NYIRABUHORO ◽  
WENPING WANG ◽  
YURI MAZEI ◽  
JUN YANG
Keyword(s):  
Shell Length ◽  
Short Distance ◽  
Testate Amoeba ◽  
Morphometric Data ◽  
Shell Surface ◽  
Aperture Diameter ◽  
Spine Length ◽  
Southeast China ◽  
Frequency Distributions ◽  
Shell Width

Difflugia australis, first described by Playfair (1918), has a unique morphotype. However, in the absence of morphometric data, it has not yet been reliably classified within the largest testate amoeba genus Difflugia. In this study D. australis collected from a subtropical reservoir in southeast China was investigated by means of light and scanning electron microscopy. Basing on biometrical data, we provide an improved diagnosis of this little known species. Difflugia australis is different from other similar congeners (i.e., D. bacillariarum Perty, 1849 and D. elegans Penard, 1890) mainly by the combination of the following features: the shell is broadly ovate, with rounded dome and convex sides converging down to a very short distance from the aperture and diverging suddenly into a short rim (collar). It is usually more or less asymmetrical, with one side being more dilated than the other. The shell surface is slightly smooth, composed of flat siliceous plates of irregular shape and size, mixed with fine grains; microbial spores of comparable forms are spread on the shell surface; particles are often interspersed with a network of organic cement with unique mesh pattern; one (sometimes two) slanting spine-like posterior end of the shell is variable in form; collar is mainly formed by small plates of equal size. The dimensions of the shell are: total shell length 88–106 µm; shell width 53–88 µm; aperture diameter 19–28 µm; collar height 3–6 µm; spine length 3‒23 μm. The size frequency distributions of both total shell length and shell width indicate that it is a size-monomorphic species with low variability. 

scholarly journals Prediction Accuracies of Genomic Selection for Nine Commercially Important Traits in the Portuguese Oyster (Crassostrea angulata) Using DArT-Seq Technology

Genes ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 210
Author(s):  
Sang V. Vu ◽  
Cedric Gondro ◽  
Ngoc T. H. Nguyen ◽  
Arthur R. Gilmour ◽  
Rick Tearle ◽  
...  
Keyword(s):  
Moisture Content ◽  
Genomic Selection ◽  
Shell Length ◽  
Prediction Accuracy ◽  
Genomic Information ◽  
Morphometric Traits ◽  
Shell Weight ◽  
Shell Width ◽  
Crassostrea Angulata ◽  
Selection For

Genomic selection has been widely used in terrestrial animals but has had limited application in aquaculture due to relatively high genotyping costs. Genomic information has an important role in improving the prediction accuracy of breeding values, especially for traits that are difficult or expensive to measure. The purposes of this study were to (i) further evaluate the use of genomic information to improve prediction accuracies of breeding values from, (ii) compare different prediction methods (BayesA, BayesCπ and GBLUP) on prediction accuracies in our field data, and (iii) investigate the effects of different SNP marker densities on prediction accuracies of traits in the Portuguese oyster (Crassostrea angulata). The traits studied are all of economic importance and included morphometric traits (shell length, shell width, shell depth, shell weight), edibility traits (tenderness, taste, moisture content), and disease traits (Polydora sp. and Marteilioides chungmuensis). A total of 18,849 single nucleotide polymorphisms were obtained from genotyping by sequencing and used to estimate genetic parameters (heritability and genetic correlation) and the prediction accuracy of genomic selection for these traits. Multi-locus mixed model analysis indicated high estimates of heritability for edibility traits; 0.44 for moisture content, 0.59 for taste, and 0.72 for tenderness. The morphometric traits, shell length, shell width, shell depth and shell weight had estimated genomic heritabilities ranging from 0.28 to 0.55. The genomic heritabilities were relatively low for the disease related traits: Polydora sp. prevalence (0.11) and M. chungmuensis (0.10). Genomic correlations between whole weight and other morphometric traits were from moderate to high and positive (0.58–0.90). However, unfavourably positive genomic correlations were observed between whole weight and the disease traits (0.35–0.37). The genomic best linear unbiased prediction method (GBLUP) showed slightly higher accuracy for the traits studied (0.240–0.794) compared with both BayesA and BayesCπ methods but these differences were not significant. In addition, there is a large potential for using low-density SNP markers for genomic selection in this population at a number of 3000 SNPs. Therefore, there is the prospect to improve morphometric, edibility and disease related traits using genomic information in this species.

scholarly journals Effects of low-pH stress on shell traits of the dove snail, <i>Anachis misera</i>, inhabiting shallow-vent environments off Kueishan Islet, Taiwan

2015 ◽  
Vol 12 (9) ◽  
pp. 2631-2639 ◽  
Author(s):  
Y. J. Chen ◽  
J. Y. Wu ◽  
C. T. A. Chen ◽  
L. L. Liu
Keyword(s):  
Shell Length ◽  
Shell Thickness ◽  
Expression Profiles ◽  
Shell Shape ◽  
Natural Environments ◽  
Additional Information ◽  
Shell Width ◽  
T1 And T2 ◽  
Body Whorl ◽  
Protein Expression Profiles

Abstract. The effects of naturally acidified seawater on shell traits were quantified through the comparison of dove snails (Family: Columbellidae) Anachis misera from vent environments with Euplica sp. from non-vent sites in northeastern Taiwan. Samples of A. misera were collected around a shallow vent (24.8341° N, 121.96191° E), which included the east, south, southwest, and northwest sites. An absence of Anachis snails was found in the most acidic north site (pH 7.19–7.25). Based on the similarities of protein expression profiles, the Anachis snails were classified into two groups, i.e., V-South (pH 7.78–7.82) and V-Rest (pH 7.31–7.83). Comparing their shell traits to the non-vent Euplica sp. from Da-xi (DX) and Geng-fang (GF) (pH 8.1–8.2), a difference in shell shape (shell width : shell length) was found, with the populations having more globular shells than the non-vent ones. The means of shell width were significantly different among sites (p < 0.01), with a descending order of GF > DX > V-South and V-Rest. The relationships of shell length to total weight were curvilinear for both Anachis and Euplica snails. The logarithmically transformed slopes differed significantly among sites, and the mean body weight of the GF population was greater than that of the others (p < 0.01). Positive correlations between shell length and shell thickness of body whorl (T1) and penultimate whorl (T2) were only observed in non-vent GF and DX populations. Anachis snails from vent sites were thinner in T1 and T2 compared to the Euplica snails from non-vent sites (p < 0.05). Within each vent group, shell thickness between T1 and T2 was insignificantly different. Between vent groups, T1 and T2 from V-Rest showed a decrease of 10.6 and 10.2%, respectively, compared to V-South ones. The decrease of T1 and T2 between vent Anachis snails and non-vent Euplica snails was as great as 55.6 and 29.0%, respectively. This was the first study to compare snail's morphological traits under varying shallow-vent stresses with populations previously classified by biochemical responses. Overall, the shallow-vent-based findings provide additional information from subtropics on the effects of acidified seawater on gastropod snails in natural environments.

Morphometric relationships in Hordeum vulgare (Triticeae, Poaceae). II. Hordeum agriocrithon, H. distichum, H. lagunculiforme, H. spontaneum, and H. vulgare

1983 ◽  
Vol 61 (7) ◽  
pp. 2023-2031 ◽  
Author(s):  
Bernard R. Baum
Keyword(s):  
Hordeum Vulgare ◽  
Phylogenetic Trees ◽  
Morphometric Data ◽  
Hordeum Vulgare L ◽  
Frequency Distributions ◽  
Entire Data ◽  
Morphometric Analyses ◽  
The Status ◽  
Discriminant Analyses ◽  
Cross Tabulation

Morphometric analyses of five morphs in Hordeum vulgare L. consisted of: computation of general statistics and frequency distributions by character for the entire data and for each morph separately; cross tabulation; various discriminant analyses; computation of Jardine and Sibson's (1968. Math. Biosci. 2: 465–482) information radius between the morphs followed by Bk clustering; and computation of phylogenetic trees from the transformed information radius matrix using three related methods. It is concluded that on the basis of morphometric data, excluding the traditional characters, that at least three morphs within H. vulgare (sensu lato) ought to be recognized as taxonomic entities. These are known as H. spontaneum C. Koch, H. distichum L., and H. vulgare (wild, two-row, and six-row barley, respectively). The hybrids and hybrid derivatives, often referred to as H. agriocrithon Åberg, are not regarded as entities but as products of interaction. The status of H. lagunculiforme Bakht. is uncertain and needs to be further investigated. It is postulated that a lagunculiforme-like entity might have been the progenitor of the group.

Shell morphometrics of three species of gadilid Scaphopoda (Mollusca) from the Southwestern Atlantic Ocean: comparing the discriminating power of primary and secondary descriptors

Zootaxa ◽  
2004 ◽  
Vol 706 (1) ◽  
pp. 1 ◽  
Author(s):  
RICARDO SILVA ABSALÃO ◽  
THIAGO SILVA DE PAULA
Keyword(s):  
Atlantic Ocean ◽  
Discriminant Function Analysis ◽  
Shell Length ◽  
Function Analysis ◽  
Southwestern Atlantic ◽  
Morphometric Data ◽  
Maximum Width ◽  
Discriminating Power ◽  
Southwestern Atlantic Ocean ◽  
Mollusc Species

Shell morphometric data are potentially useful in discriminating among morphologically similar mollusc species. Only a few studies, however, have assessed the value of this method for identifying and delimiting scaphopod taxa. We attempted to discriminate three southwestern-Atlantic species of gadilid scaphopods, Gadila acus (Dall, 1889), Cadulus braziliensis Henderson, 1920, and Polyschides tetraschistus (Watson, 1879) using Discriminant Function Analysis of shell morphometric data. We tested the efficiency of three morphometric indices proposed by Shimek (1989), nine direct shell measurements proposed by Steiner & Linse (2000), and three newly proposed morphometric indices. Shimek s (1989) indices correctly assigned 133 of 150 specimens (88.67%), whereas the direct shell measurements data correctly assigned 149 specimens (99.34%). The most efficient set of parameters assigning all specimens correctly consisted of: 1) the height of the posterior aperture, 2) the total length of the shell, 3) the maximum arc, 4) the ratio of total shell length and the distance from the dorsal aperture to the point of maximum width, 5) the ratio of the maximum shell diameter and the apertural diameter, and 6) the ratio of the height and width of the posterior aperture. Because this combination of variables was 100% efficient in discriminating among the three species, we recommend its use as the best tool for separating these slender gadilid scaphopods.

scholarly journals Telaah morfometrik Pinctada margaritifera untuk pengembangan usaha budidaya

2018 ◽  
Vol 6 (1) ◽  
Author(s):  
Karel Sumtaki ◽  
Ockstan J. J. Kalesaran ◽  
Cyska Lumenta
Keyword(s):  
Water Quality ◽  
Shell Length ◽  
Current Velocity ◽  
Quality Parameters ◽  
Morphometric Measurements ◽  
Shell Weight ◽  
Pinctada Margaritifera ◽  
Shell Width ◽  
Aquaculture Development ◽  
Quality Measurements

This study aimed to analyze the size of shell length, shell width and total weight of Pinctada margaritifera shells, and water quality parameters for the aquaculture development. Morphometric measurements include: shell length (PC), and shell width (LC), shell weight (BT). The results showed that PC size 8 - 11.99 cm, LC 8 - 9.99 cm and BT 80 - 99.99 gram dominate the Arakan waters  while PC size 6 - 9.99 cm, LC 6 - 7.99 cm and BT 60 - 79.99 gram dominate the Bahoi  waters. The results of water quality measurements in both locations are Bahoi waters, namely: 29-32oC, DO 7-8,5 mg/l, pH 7,8-7,9, salinity, 28-32 ppt, 4,5- 7 meters, 11 cm/sec. While in Arakan waters, the temperature was 30-30,8oC, DO 6,3-6,7 mg/l, pH 7,6-7,7 salinity 30 ppt, brightness 4-5 meter, current velocity 4,5 cm / second. Both locations were feasible for the development of pearl aquacultureKeywords: Morphometric, Pinctada margaritifera, Aquaculture

scholarly journals Colour and Morphometric Variation of Donacid Bivalves from Nepa Beach, Madura Island, Indonesia

2017 ◽  
Vol 9 (3) ◽  
pp. 466 ◽  
Author(s):  
Reni Ambarwati ◽  
Ulfi Faizah
Keyword(s):  
Regression Analysis ◽  
Shell Length ◽  
Shell Height ◽  
Morphological Characteristics ◽  
Morphological Characters ◽  
Colour Pattern ◽  
Morphometric Variation ◽  
Shell Width ◽  
Northern Shore

<p class="IsiAbstrakIndo"><span lang="EN-GB">Donacid bivalves vary in colour, pattern, and the shape of the shells. A population of donacid bivalves had been found in the northern shore of Madura Island, Indonesia. This study aimed to identify the donacids found in northern shore of Madura Island as well as to describe their variation on morphometric and morphological characters. Colour and pattern of 215 shells were observed and carefully photographed. Morphometric of the shells including the shell height, shell length, shell width, dorsal length, and umbo-margin length were measured and then their patterns were analyzed using regression analysis. The results revealed that there were two species of donacid bivalves in Nepa Beach, namely </span><em><span lang="EN-GB">Donax cuneata</span></em><span lang="EN-GB"> and </span><em><span lang="EN-GB">Donax faba</span></em><span lang="EN-GB"> with different morphological characteristics, including twelve different patterns and colours of the shells. These variations were described completely in this paper. This study contributes to the research on bivalve taxonomy, and is useful for the identification of donacid bivalves based on morphological characteristics.</span></p>

scholarly journals Growth of the ass's ear abalone (Haliotis asinina Linné) on Heron Reef, tropical eastern Australia

1995 ◽  
Vol 46 (3) ◽  
pp. 571 ◽  
Author(s):  
DC McNamara ◽  
CR Johnson
Keyword(s):  
Growth Rate ◽  
Shell Length ◽  
Frequency Distributions ◽  
Haliotis Asinina ◽  
Length Relationship ◽  
Abalone Species ◽  
Eastern Australia ◽  
Field Peak ◽  
One Year

Growth of ass's ear abalone (Haliotis asinina) was measured in situ (mark-recapture of adults) and in aquaria (juveniles) on Heron Reef, Queensland. A growth curve (y = 4.27L2.03 e-u, where y is the growth rate, L is the shell length, and u = 0.27L0.88) fitted to these data indicated a sigmoidal age-length relationship. It is estimated that H. asinina may grow from 2 mm to 35.6 mm in shell length in six months and 55.0 mm in one year. These growth estimates are consistent with temporal shifts in the size-frequency distributions of juveniles in the field. Peak growth rates, estimated at over 120 mm year-1 in young abalone (approximately 3-4 months of age), are the highest recorded for any abalone species.

scholarly journals Morphologycal and Molecular Partial Histone-H3 Characterization of Bintan Sea Snail Gonggong (Strombus sp.) as a Species Validation

2019 ◽  
Vol 26 (2) ◽  
pp. 56
Author(s):  
Lily Viruly ◽  
Nuri Andarwulan ◽  
Maggy T. Suhartono ◽  
Mala Nurilmala
Keyword(s):  
Phylogenetic Analysis ◽  
Genetic Distance ◽  
Molecular Characterization ◽  
Dna Sequences ◽  
Shell Length ◽  
Bioinformatics Analysis ◽  
Economic Value ◽  
Histone H3 ◽  
Shell Width

Sea snail gonggong is an icon of Tanjungpinang-Riau Islands Province. It is a favorite seafood item in Riau Islands Province, and is high economic value but not known widely yet. Until now, sea snail gonggong has been highly exploited but the research on this snail is very limited. The aim of this study was to morphology and molecular characterization of Bintan gonggong snail (Strombus sp.) as a species validation. Bintan gonggong snail included thick-shelled gonggong and thin-shelled gonggong. Morphology identifcation of species Bintan gonggong snail was based on morphometric variability. Molecular identifcation used partial Histone-H3, MEGA version 6.06, and bioinformatics analysis. The result showed that the morphological identifcation of thick-shelled and thin-shelled gonggong based on shell width, the lip thickness, and total weight signifcantly different, but other variables (i.e shell length, shell depth, aperture length, and gonggong weight) were not signifcantly different (p<0.05). Resulted of a molecular identifcation with phylogenetic analysis that the thin-shelled and thick-shelled Bintan gonggong snails were 1 species and a genetic distance of 1%. They were not species Strombus canarium, Strombus vitatus, and Strombus epidromis. Bintan gonggong snails were Strombus turturella (Leavistrombus turturella). DNA sequences of Bintan gonggong have been registered in Gen-Bank with registration numbers MH348131 (thinshelled gonggong) and MH348132 (thick-shelled gonggong).

scholarly journals Influence of two management systems on the growth performance of adult African giant land snails (Archachatina marginata)

2019 ◽  
Vol 11 (2) ◽  
pp. 424-428
Author(s):  
Z. Dododawa ◽  
B. N. Ejidike
Keyword(s):  
Weight Gain ◽  
Shell Length ◽  
Management System ◽  
Mean Value ◽  
Land Snails ◽  
Intensive Management ◽  
Extensive Management ◽  
Shell Width ◽  
Significant Difference ◽  
Length Increment

African gaint land snails are important as means of alleviating acute protein shortage in Nigeria livestock Industries. The present study aimed to study the influence of intensive and extensive management systems on the growth Performance of adult African Giant Land Snails (Archachatina marginata) was carried out in the wildlife domestication unit of the Department of Forest Resources and Wildlife Management, University of Benin, Benin City, Nigeria. Ninety  African giant land snails (A. marginata) of average body weight 160.31g ± 0.38g were used for the study. The snails were grouped into two- Group A and Group B. 45 snails in group A were raised in an intensive system of management while 45 snails in group B were raised in an extensive system of management. The data collected on weight gain, shell length increment and shell width increment during the experiment were subjected to student t-Test at 5% significant level. Results showed that there was a significant difference at (p<0.05) in the weight gain. The intensive management system had a higher weight gain of 128.96g with mean value of 4.96 while the extensive management system had a weight gain of 88.37g with mean value of 3.40. There was no significant difference at (p>0.05) in the shell length increment. The snails in the extensive management system had the higher shell length increment of 5.32cm with mean value of 0.20 while the snails in the intensive management system had a shell length increment of 2.43cm with mean value of 0.09. There was a significant difference at (p<0.05) in the shell width increment. The snails in the extensive management system had the higher shell width increment of 9.31cm with mean value of 0.36 while the snails in the intensive management system had a shell width increment of 4.30cm with mean value of 0.17. The snails in the intensive system had a Feed Conversion Ratio of 5.03. For better growth performance of A. marginata in terms of weight gain, snail farmers should raise their snails in an intensive system of management and formulated diet should be used in feeding the snails along side with natural feed such as leaves and fruits.

Effect of replacing maize with plantain peels on the performance traits and haematological characteristics of African giant land snail

2022 ◽  
Vol 4 (1) ◽  
pp. 001-006
Author(s):  
Yeigba, B Japhet ◽  
Kpun, IP ◽  
Birigeni, D Charity
Keyword(s):  
Weight Gain ◽  
Blood Cell ◽  
Feed Intake ◽  
Shell Length ◽  
Niger Delta ◽  
Shell Thickness ◽  
Hematological Parameters ◽  
Land Snail ◽  
Land Snails ◽  
Shell Width

The study was carried out at the Niger Delta University, Faculty of Agriculture Teaching and Research Farm, Bayelsa State. A total of Ninety six (96) growing snails (Archachatina marginata). Using Plantain peel as an additive, four diets were formulated at the levels of 0%, 3%, 6%, and 9% to form the treatment diets. The experiment lasted for eight (8) weeks during which the weight gain, feed intake, shell width, shell length, shell thickness and hematological parameters were obtained. The weight gain, shell width, shell length and shell thickness are not significantly different (p<0.05) whereas, the feed intake differed significantly (p<0.05) for all the treatment diets in the experiment. From the results, it was concluded that concentrate with 0% inclusion of Plantain peel meal was suitable for snail diets as it gave the best performance. The hematological parameters measured in the African giant land snails are White blood cell, Neutrophile and Lymphocyte differed significantly (p<0.05). Plantain peel can serve as source of potassium for other animals, as the highest percentage of potassium was found in the hemolymph of snails fed with 9% inclusion of plantain peel. It is recommended that; there should be no inclusion of plantain peels in the diet of the African giant land snails in order to achieve higher weight gain and feed intake.

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