Morphometry of the shell in Scaphopoda (Mollusca): a tool for the discrimination of taxa

2020 ◽  
pp. 1-12
Author(s):  
Leonardo Santos de Souza ◽  
Carlos Henrique Soares Caetano
Keyword(s):  
Input Data ◽  
Species Level ◽  
Shell Morphology ◽  
Species Discrimination ◽  
Correct Classification ◽  
Congeneric Species ◽  
Discrimination Power ◽  
Inconsistent Result ◽  
The Family ◽  
Family Level

Abstract The alpha taxonomy of scaphopods is based mainly on the shell morphology, as it is for most molluscs. In the last three decades, the employment of morphometric variables of the shell in combination with statistics has considerably increased to aid species discrimination, but this has not been used above species level. In this study, a traditional morphometric approach was used to distinguish congeners, genera and families within the orders Dentallida and Gadilida. We studied 28 species of scaphopods from Brazil, belonging to 12 genera and five families. Twelve morphometric variables were measured, and a correlation test was done to select a set of variables without correlation as input data to perform a discriminant analysis. In the analysis of congeners, the discrimination power was high in both orders. Among the genera studied, the robustness of the analysis was drastically reduced in Dentaliida, while Gadilida maintained a high percentage of correct classifications. At the family level, both orders presented high percentages of correct classification, but the imbalance of cases for each taxon masks an inconsistent result. Based on our results, the morphometric approach was a useful tool to discriminate congeneric species of both orders and to discriminate the genera of Gadilida.

The early derivative water mites (Acari: Hydrachnidia, superfamilies Eylaoidea, Hydrachnoidea and Hydryphantoidea) of Madagascar

Zootaxa ◽  
2020 ◽  
Vol 4727 (1) ◽  
pp. 1-77
Author(s):  
REINHARD GERECKE
Keyword(s):  
Species Level ◽  
Water Mites ◽  
General Introduction ◽  
Dichotomous Key ◽  
The Family ◽  
Family Level ◽  
First Time

A general introduction to the water mites of Madagascar is given, together with a survey of the diversity of the early derivative superfamilies Eylaoidea, Hydrachnoidea, and Hydryphantoidea. The family Teratothyadidae (genera Teratothyas and Teratothyasides) and the hydryphantid subfamilies Euthyadinae (genera Javathyas and Trichothyas) and Wandesiinae (genus Wandesia) are recorded for the first time from Madagascar, the latter being new for the Ethiopian bioregion. One subgenus in the family Teratothyadidae, Ascoteratothyas subgen. nov. (genus Teratothyas) and eighteen species are described as new to science: Hydrodroma amoenoderma, H. lasioderma, H. megalonyx, H. mesembrina, H. poseidon, Javathyas nasipalpis, Wandesia pelipoda, W. anjozorobensis, Teratothyas (s. str.) digitata, T. (s. str.) aucta, T. (s. str.) proceripapillata, T. (s. str.) planipapillata, T. (Ascoteratothyas) levigata, T. (A.) porrigens, T. (A.) reducta, Teratothyasides heptaplax, T. ravenala and T. vanilla. Previous Madagascan records of Hydrodroma despiciens (Müller, 1776) and H. capensis (K. Viets, 1914) are attributed to H. poseidon. The subgenus Pseudowandesia is synonymized with the nominate subgenus. New locality records for other species include the first recording on the island of Hydrodroma perreptans (K. Viets, 1913) and H. zhokhovi Tuzovskij, 2014. Limnochares connexa Tuzovskij & Gerecke 2009 is redescribed. A dichotomous key leads to species level for the groups treated here, to family level for representatives of the remaining four superfamilies present on Madagascar. 

scholarly journals Detection of enteroparasites in foliar vegetables commercialized in street- and supermarkets in Aparecida de Goiânia, Goiás, Brazil

2022 ◽  
Vol 82 ◽  
Author(s):  
L. F. N. Rocha ◽  
S. S. Rodrigues ◽  
T. B. Santos ◽  
M. F. Pereira ◽  
J. Rodrigues
Keyword(s):  
Intestinal Parasites ◽  
Species Level ◽  
Hymenolepis Nana ◽  
Collard Greens ◽  
Dipylidium Caninum ◽  
Route Of Transmission ◽  
The Family ◽  
Family Level ◽  
The City ◽  
Collard Green

Abstract Foliar vegetables contaminated with fecal residues are an important route of transmission of intestinal parasites to humans. The aim of this study was to evaluate the presence of parasitic forms of protozoa and helminths on lettuces (Lactuca sativa) and collard greens (Brassica oleracea) sold in street- and supermarkets in the city of Aparecida de Goiânia, Goiás, Brazil. A total of 30 samples of each vegetable (15 samples from each supermarkets and street markets) was analyzed. All samples were processed by spontaneous sedimentation method and centrifugal flotation. In 45% of the samples, immature forms of intestinal parasites were identified with 66.7% helminths eggs and 33.3% protozoan cysts or oocysts. Significantly more lettuce samples were contaminated with eggs, cysts or oocyst of at least one parasite than collard green samples (U=216; Z=-3.45; P <0.001). The parasitic forms were identified morphologically up to the family level with eggs of Ancylostomatidae, Strongyloididae, Ascarididae and Taeniidae, or oocysts of Eimeriidae, to the genus with Cystoisospora sp. and Toxocara sp., and to the species level with Cystoisospora canis, Dipylidium caninum and Hymenolepis nana. The presence of these infective agents in lettuce and collard green from both street- and supermarkets highlights the high risk of spreading parasites by eating raw vegetables sold in Aparecida de Goiânia.

Within- and between-plant distribution of harpacticoid copepods in a North Atlantic bed of Laminaria ochroleuca

2006 ◽  
Vol 86 (2) ◽  
pp. 309-316 ◽  
Author(s):  
Nina Larissa Arroyo ◽  
Manuel Maldonado ◽  
Keith Walters
Keyword(s):  
North Atlantic ◽  
Common Species ◽  
Taxonomic Composition ◽  
Species Level ◽  
Plant Distribution ◽  
Harpacticoid Copepods ◽  
The Family ◽  
Family Level ◽  
Laminaria Ochroleuca ◽  
Faunal Similarity

The fauna of harpacticoid copepods associated with a North Atlantic sublittoral population of Laminaria ochroleuca in Spain was investigated. Copepods belonging to four different orders, i.e. Harpacticoida, Cyclopoida, Poecilostomatoida and Siphonostomatoida, most of which were harpacticoids belonging to 17 different families were collected. Because the family Thalestridae was particularly abundant in the samples, its members were identified down to the species level, totalling 20 species. The copepod fauna was richer and more diverse on holdfasts than on fronds, irrespective of considering the entire harpacticoid assemblage at the family level or just the family Thalestridae at the species level. The effect of these two within-plant microhabitats on the taxonomic composition of the copepod fauna was substantial, with faunal similarity between fronds of plants from different sampling quadrats being usually higher than that between the frond and the holdfast of the same plant. Thalestridae, Harpacticidae and Tisbidae predominated on the fronds, while Diosaccidae, Ameiridae and Ectinosomatidae predominated on the holdfasts. Among the thalestrids, Parathalestris clausi, Paradactylopodia sp.1, Dactylopusia tisboides, and Dactylopusia vulgaris were common species, with Parathalestris clausi being the most abundant copepod on both fronds and holdfasts. In summary, the fauna of the holdfasts consists mostly of common, eurytopic species, while the fauna of the fronds comprises rare taxa—at least within the scope of the study—with low total abundances and/or usually occurring in few plants.

Ecological relationships between lianas and trees in lowland rain forest in Sabah, East Malaysia

1993 ◽  
Vol 9 (4) ◽  
pp. 469-490 ◽  
Author(s):  
E. J. F. Campbell ◽  
D. McC. Newbery
Keyword(s):  
Negative Binomial ◽  
Species Level ◽  
Lowland Rain Forest ◽  
Dipterocarp Forest ◽  
Ecological Relationships ◽  
East Malaysia ◽  
The Family ◽  
Family Level ◽  
The Mean ◽  
Individual Trees

ABSTRACTNumbers of lianas ≥2 cm gbh were recorded on trees ≥30 cm gbh in two 4 ha plots of dipterocarp forest. Associations between lianas and trees of the 12 commonest families and 16 commonest species were analysed. Liana density was 882 ha-1. Fifty-seven per cent of trees supported lianas and the mean number lianas per tree was 2.1. Lianas were highly aggregated on individual trees in most families; numbers of lianas per tree followed the negative binomial distribution for the Dipterocarpaceae but not Euphorbiaceae. Dipterocarpaceae and Euphorbiaceae differed in susceptibility, with 41 and 64% of their trees respectively supporting lianas. The proportions of trees with lianas (i.e. % trees laden) were correlated between plots at the species, but not the family, level. They were not related to tree girth; differences in proportions between families and species were maintained for trees in the 30–40 cm gbh class. At the species level, proportions of trees with lianas and the mean number of lianas per tree were significantly inversely correlated with mean branch-free bole height of trees in the 30–40 cm gbh class. Increased branch-free bole height and associated branch shedding may therefore decrease the susceptibility of trees to lianas and explain the lower susceptibility in the Dipterocarpaceae than the Euphorbiaceae.

scholarly journals Unearthing LTR retrotransposon gag genes co-opted in the deep evolution of eukaryotes

2021 ◽  
Author(s):  
Jianhua Wang ◽  
Guan-Zhu Han
Keyword(s):  
Gene Expression ◽  
Selective Pressure ◽  
Ltr Retrotransposon ◽  
Ltr Retrotransposons ◽  
Cellular Functions ◽  
The Family ◽  
Family Level ◽  
Gene Expression Analyses ◽  
Comprehensive Picture ◽  
Gypsy Retrotransposons

Abstract LTR retrotransposons comprise a major component of the genomes of eukaryotes. On occasion, retrotransposon genes can be recruited by their hosts for diverse functions, a process formally referred to as co-option. However, a comprehensive picture of LTR retrotransposon gag gene co-option in eukaryotes is still lacking, with several documented cases exclusively involving Ty3/Gypsy retrotransposons in animals. Here we use a phylogenomic approach to systemically unearth co-option of retrotransposon gag genes above the family level of taxonomy in 2,011 eukaryotes, namely co-option occurring during the deep evolution of eukaryotes. We identify a total of 14 independent gag gene co-option events across more than 740 eukaryote families, eight of which have not been reported previously. Among these retrotransposon gag gene co-option events, nine, four, and one involve gag genes of Ty3/Gypsy, Ty1/Copia, and Bel-Pao retrotransposons, respectively. Seven, four, and three co-option events occurred in animals, plants, and fungi, respectively. Interestingly, two co-option events took place in the early evolution of angiosperms. Both selective pressure and gene expression analyses further support that these co-opted gag genes might perform diverse cellular functions in their hosts, and several co-opted gag genes might be subject to positive selection. Taken together, our results provide a comprehensive picture of LTR retrotransposon gag gene co-option events that occurred during the deep evolution of eukaryotes, and suggest paucity of LTR retrotransposon gag gene co-option during the deep evolution of eukaryotes.

scholarly journals The Role of Botanical Families in Medicinal Ethnobotany: A Phylogenetic Perspective

Plants ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 163
Author(s):  
Airy Gras ◽  
Oriane Hidalgo ◽  
Ugo D’Ambrosio ◽  
Montse Parada ◽  
Teresa Garnatje ◽  
...  
Keyword(s):  
Diversity Indices ◽  
Specific Level ◽  
Medicinal Uses ◽  
The Family ◽  
Family Level ◽  
Phylogenetic Level ◽  
Molecular Phylogenetic ◽  
Quantitative Analyses ◽  
Medicinal Flora

Studies suggesting that medicinal plants are not chosen at random are becoming more common. The goal of this work is to shed light on the role of botanical families in ethnobotany, depicting in a molecular phylogenetic frame the relationships between families and medicinal uses of vascular plants in several Catalan-speaking territories. The simple quantitative analyses for ailments categories and the construction of families and disorders matrix were carried out in this study. A Bayesian approach was used to estimate the over- and underused families in the medicinal flora. Phylogenetically informed analyses were carried out to identify lineages in which there is an overrepresentation of families in a given category of use, i.e., hot nodes. The ethnobotanicity index, at a specific level, was calculated and also adapted to the family level. Two diversity indices to measure the richness of reported taxa within each family were calculated. A total of 47,630 use reports were analysed. These uses are grouped in 120 botanical families. The ethnobotanicity index for this area is 14.44% and the ethnobotanicity index at the family level is 68.21%. The most-reported families are Lamiaceae and Asteraceae and the most reported troubles are disorders of the digestive and nutritional system. Based on the meta-analytic results, indicating hot nodes of useful plants at the phylogenetic level, specific ethnopharmacological research may be suggested, including a phytochemical approach of particularly interesting taxa.

scholarly journals Consistent Metagenome-Derived Metrics Verify and Delineate Bacterial Species Boundaries

mSystems ◽  
2020 ◽  
Vol 5 (1) ◽  
Author(s):  
Matthew R. Olm ◽  
Alexander Crits-Christoph ◽  
Spencer Diamond ◽  
Adi Lavy ◽  
Paula B. Matheus Carnevali ◽  
...  
Keyword(s):  
Bacterial Diversity ◽  
Ribosomal Proteins ◽  
Large Scale ◽  
Bacterial Species ◽  
Bacterial Genome ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Species Discrimination ◽  
Bacterial Genomes ◽  
Discrimination Power

ABSTRACT Longstanding questions relate to the existence of naturally distinct bacterial species and genetic approaches to distinguish them. Bacterial genomes in public databases form distinct groups, but these databases are subject to isolation and deposition biases. To avoid these biases, we compared 5,203 bacterial genomes from 1,457 environmental metagenomic samples to test for distinct clouds of diversity and evaluated metrics that could be used to define the species boundary. Bacterial genomes from the human gut, soil, and the ocean all exhibited gaps in whole-genome average nucleotide identities (ANI) near the previously suggested species threshold of 95% ANI. While genome-wide ratios of nonsynonymous and synonymous nucleotide differences (dN/dS) decrease until ANI values approach ∼98%, two methods for estimating homologous recombination approached zero at ∼95% ANI, supporting breakdown of recombination due to sequence divergence as a species-forming force. We evaluated 107 genome-based metrics for their ability to distinguish species when full genomes are not recovered. Full-length 16S rRNA genes were least useful, in part because they were underrecovered from metagenomes. However, many ribosomal proteins displayed both high metagenomic recoverability and species discrimination power. Taken together, our results verify the existence of sequence-discrete microbial species in metagenome-derived genomes and highlight the usefulness of ribosomal genes for gene-level species discrimination. IMPORTANCE There is controversy about whether bacterial diversity is clustered into distinct species groups or exists as a continuum. To address this issue, we analyzed bacterial genome databases and reports from several previous large-scale environment studies and identified clear discrete groups of species-level bacterial diversity in all cases. Genetic analysis further revealed that quasi-sexual reproduction via horizontal gene transfer is likely a key evolutionary force that maintains bacterial species integrity. We next benchmarked over 100 metrics to distinguish these bacterial species from each other and identified several genes encoding ribosomal proteins with high species discrimination power. Overall, the results from this study provide best practices for bacterial species delineation based on genome content and insight into the nature of bacterial species population genetics.

scholarly journals Inuit plant use in the eastern Subarctic: comparative ethnobotany in Kangiqsualujjuaq, Nunavik, and in Nain, Nunatsiavut

Botany ◽  
2019 ◽  
Vol 97 (5) ◽  
pp. 271-282
Author(s):  
Alain Cuerrier ◽  
Courtenay Clark ◽  
Christian H. Norton
Keyword(s):  
Lifestyle Changes ◽  
Ethnobotanical Knowledge ◽  
Structured Interviews ◽  
Medicinal Species ◽  
Medicinal Uses ◽  
Plant Uses ◽  
The Family ◽  
Plant Names ◽  
Family Level ◽  
Comparative Ethnobotany

Plants are important in traditional Inuit life. They are used for food, tea, medicine, etc. Based on semi-structured interviews with 35 informants, we documented and compared plant names and uses in Kangiqsualujjuaq, Nunavik, and in Nain, Nunatsiavut. Plant names and uses were expected to be similar between communities owing to common boreal–subarctic environments and cultural ties. Both communities reported the same number of taxa, with equivalent proportions of vascular and nonvascular plants, growth forms, use categories, and medicinal uses. Forty-three species were used in each community, for a total of 78 species from 39 families. Despite a high overlap in species distributions, only 35% of nonvascular and 56% of vascular species were used in both communities. Correspondence was higher at the family level (64% of nonvascular and 75% of vascular families shared). The Ericaceae family was the most used, followed by Rosaceae. Thirteen of 30 medicinal species were shared between communities. There was a low correspondence regarding the conditions for which the medicinal species were used. Edible taxa were shared the most (52%). Plant uses unique to either Nain or Kangiqsualujjuaq may reveal separate bodies of traditional knowledge, or may reflect an overall loss of ethnobotanical knowledge in the Subarctic due to recent lifestyle changes.

Phylogeny accurately predicts behaviour in Indian Ocean Clitaetra spiders (Araneae:Nephilidae)

2009 ◽  
Vol 23 (3) ◽  
pp. 193 ◽  
Author(s):  
Matjaž Kuntner ◽  
Ingi Agnarsson
Keyword(s):  
South Africa ◽  
Phylogenetic Analysis ◽  
Indian Ocean ◽  
Species Level ◽  
Web Architecture ◽  
Evolutionarily Conserved ◽  
The Family ◽  
Behavioural Biology

Phylogenies are underutilised, powerful predictors of traits in unstudied species. We tested phylogenetic predictions of web-related behaviour in Clitaetra Simon, 1889, an Afro-Indian spider genus of the family Nephilidae. Clitaetra is phylogenetically sister to all other nephilids and thus important for understanding ancestral traits. Behavioural information on Clitaetra has been limited to only C. irenae Kuntner, 2006 from South Africa which constructs ladder webs. A resolved species-level phylogeny unambiguously optimised Clitaetra behavioural biology and predicted web traits in five unstudied species and a uniform intrageneric nephilid web biology. We tested these predictions by studying the ecology and web biology of C. perroti Simon, 1894 on Madagascar and C. episinoides Simon, 1889 on Mayotte. We confirm predicted arboricolous web architecture in these species. The expected ontogenetic allometric transition from orbs in juveniles to elongate ladder webs in adults was statistically significant in C. perroti, whereas marginally not significant in C. episinoides. We demonstrate the persistence of the temporary spiral in finished Clitaetra webs. A morphological and behavioural phylogenetic analysis resulted in unchanged topology and persisting unambiguous behavioural synapomorphies. Our results support the homology of Clitaetra hub reinforcement with the nephilid hub-cup. In Clitaetra, behaviour was highly predictable and remained consistent with new observations. Our results confirm that nephilid web biology is evolutionarily conserved within genera.

Sign in / Sign up

Export Citation Format

Share Document