scholarly journals A morphospace of planktonic marine diatoms. II. Sampling standardization and spatial disparity partitioning

Paleobiology ◽  
2015 ◽  
Vol 41 (1) ◽  
pp. 68-88 ◽  
Author(s):  
Benjamin Kotrc ◽  
Andrew H. Knoll

AbstractMorphospace occupation through time provides a view of diversification distinct from the more familiar taxonomic tabulations. However, this view is subject to the same geological biases long recognized in studies of taxonomic diversification, where techniques for correcting secular bias in sampling have become standard practice. In this study, we apply sampling standardization techniques to a morphospace investigation to test whether observed stratigraphic trends in morphospace occupation are artifacts of trends in sampling. When sampling bias is corrected by randomized subsampling, all disparity metrics show stationary patterns, or at most directional changes of small magnitude. Metrics describing the average dispersion of taxa in morphospace are less subject to sampling bias than those describing the total extent of morphospace occupied. We also investigate a measure of disparity that is insensitive to sampling intensity, introducing a geographic component of morphological disparity. By analogy to α and β components of taxonomic diversity, we suggest the notions of α and β disparity, and find that α disparity remains roughly constant through time. Our analysis also allows us to present the first taxonomic diversity curve of diatoms under shareholder quorum subsampling (SQS), showing similar results to previously published subsampling methods: a roughly twofold rise over the Cenozoic, with peak diversity around the Eocene/Oligocene boundary. Tests for methodological bias from choices in ordination method and data culling during morphospace construction indicate that our results are relatively insensitive to both factors: Cenozoic occupation of planktonic diatom morphospace is largely unchanging. We find a similarly stationary pattern when we directly analyze the morphological data, seeing no change in the prevalence of taxa with different sets of morphological characters. More broadly, our results make clear that a complete view of morphological disparity must consider sampling biases, which can be addressed with wellestablished, quantitative methods in morphospaces populated using occurrence-level data.

2017 ◽  
Vol 10 (1) ◽  
pp. 70-81 ◽  
Author(s):  
Muhammad Afzal Rizvi ◽  
Syed Abid Ali ◽  
Iqra Munir ◽  
Kousar Yasmeen ◽  
Rubina Abid ◽  
...  

Aim: Quinoa is a popular source of protein, minerals and alternative to traditional grains. The objective of this study is to introduce the Quinoa in the semi-arid zone of Sindh province of Pakistan. Method: A variety of NARC-9 from the agricultural Punjab province was cultivated and subjected to analyze the growth, morphological characters of the varieties obtained, saponin, protein and the elemental composition viz. Cd, Cu, Fe, K, Na, Pb, and Zn. Result: The result demonstrated the optimum growth and no disease were found in the experimental area. At least three major varieties of quinoa were obtained. Seed morphological data of these three quinoa cultivars were collected. The average saponin levels were quite reasonable. Overall proteins band pattern revealed very high polymorphism in quinoa cultivars and the results were also in good agreement with earlier studies. Conclusion: All quinoa cultivars of Madinat al-Hikmah showed high concentrations of albumin than globulin concentrations (i.e. 48-52% and 24-27%, respectively) as compared to control seeds from market that had similar concentrations of the two fractions i.e. 35.58% and 37.68%, respectively. Likewise, low concentrations of prolamin 14-16% and glutelin 11-12% compared to control seeds 13% rank our crop much better quality than the imported one in the market. The trend of elemental accumulation was followed as K >Na >Fe >Zn >Cu >Pb >Cd, while for comparison it was Na >K >Zn >Fe >Cu >Pb >Cd >Pb for wheat grown under similar conditions. Traditional grains together make a major contribution to the total nutritional element intake of the average Pakistani citizen through diet, not only because of large amounts consumed, but also in part by suitable levels of their proteins and elemental up take for good health. Thus the successful cultivation of quinoa in the semi-arid zone of Sindh will certainly prove beneficial.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Edoardo Massa ◽  
Roberto Guidetti ◽  
Michele Cesari ◽  
Lorena Rebecchi ◽  
K. Ingemar Jönsson

AbstractKristianstads Vattenrike Biosphere Reserve [KVBR] is a UNESCO designated area of Sweden possessing high biological value. Although several studies on tardigrades inhabiting Sweden have been performed, the KVBR area has been neglected. The current study investigates the tardigrade fauna of five areas of the biosphere reserve and includes 34 samples of different substrates analysed quantitatively and qualitatively. In total, 33 species of tardigrades were found in the samples, including 22 new records for the Skåne region, 15 new records for Sweden, and four species new to science. Mesobiotus emiliae sp. nov., Xerobiotus gretae sp. nov., Itaquascon magnussoni sp. nov., and Thulinius gustavi sp. nov. were described with an integrative approach (when possible) using morphological characters (light, electron scanning, and confocal laser scanning microscopies) and molecular markers (ITS2, 18S, 28S, cox1). A new protocol to increase morphological data was developed recovering mounted specimens within old slides for SEM analysis. Emended diagnoses for the genus Itaquascon and the transfer of Platicrista itaquasconoide to the genus Meplitumen are proposed. This study enriches the knowledge of the tardigrade biodiversity both within the KVBR and in Sweden and contributes to the rapidly increasing number of tardigrade species reported worldwide. The 33 species identified in the KVBR area represents 28% of all water bear species found in Sweden so far. The restricted study areas and limited number of samples collected suggests that the KVBR is very rich of tardigrades.


2021 ◽  
Vol 307 (2) ◽  
Author(s):  
Pau Carnicero ◽  
Núria Garcia-Jacas ◽  
Llorenç Sáez ◽  
Theophanis Constantinidis ◽  
Mercè Galbany-Casals

AbstractThe eastern Mediterranean basin hosts a remarkably high plant diversity. Historical connections between currently isolated areas across the Aegean region and long-distance dispersal events have been invoked to explain current distribution patterns of species. According to most recent treatments, at least two Cymbalaria species occur in this area, Cymbalaria microcalyx and C. longipes. The former comprises several intraspecific taxa, treated at different ranks by different authors based on morphological data, evidencing the need of a taxonomic revision. Additionally, some populations of C. microcalyx show exclusive morphological characters that do not match any described taxon. Here, we aim to shed light on the systematics of eastern Mediterranean Cymbalaria and to propose a classification informed by various sources of evidence. We performed molecular phylogenetic analyses using ITS, 3’ETS, ndhF and rpl32-trnL sequences and estimated the ploidy level of some taxa performing relative genome size measures. Molecular data combined with morphology support the division of traditionally delimited C. microcalyx into C. acutiloba, C. microcalyx and C. minor, corresponding to well-delimited nrDNA lineages. Furthermore, we propose to combine C. microcalyx subsp. paradoxa at the species level. A group of specimens previously thought to belong to Cymbalaria microcalyx constitute a well-defined phylogenetic and morphological entity and are described here as a new species, Cymbalaria spetae. Cymbalaria longipes is non-monophyletic, but characterized by being glabrous and diploid, unlike other eastern species. The nrDNA data suggest at least two dispersals from the mainland to the Aegean Islands, potentially facilitated by marine regressions.


2012 ◽  
Vol 10 (1) ◽  
pp. 19-44 ◽  
Author(s):  
Alfy Morales-Cazan ◽  
James S. Albert

The systematics and taxonomy of poeciliid fishes (guppies and allies) remain poorly understood despite the relative importance of these species as model systems in the biological sciences. This study focuses on testing the monophyly of the nominal poeciliine tribe Heterandriini and the genus Heterandria, through examination of the morphological characters on which the current classification is based. These characters include aspects of body shape (morphometrics), scale and fin-ray counts (meristics), pigmentation, the cephalic laterosensory system, and osteological features of the neurocranium, oral jaws and suspensorium, branchial basket, pectoral girdle, and the gonopodium and its supports. A Maximum Parsimony analysis was conducted of 150 characters coded for 56 poeciliid and outgroup species, including 22 of 45 heterandriin species (from the accounted in Parenti & Rauchenberger, 1989), or seven of nine heterandriin species (from the accounted in Lucinda & Reis, 2005). Multistate characters were analyzed as both unordered and ordered, and iterative a posteriori weighting was used to improve tree resolution. Tree topologies obtained from these analyses support the monophyly of the Middle American species of "Heterandria," which based on available phylogenetic information, are herein reassigned to the genus Pseudoxiphophorus. None of the characters used in previous studies to characterize the nominal taxon Heterandriini are found to be unambiguously diagnostic. Some of these characters are shared with species in other poeciliid tribes, and others are reversed within the Heterandriini. These results support the hypothesis that Pseudoxiphophorus is monophyletic, and that this clade is not the closest relative of H. formosa (the type species) from southeastern North America. Available morphological data are not sufficient to assess the phylogenetic relationships of H. formosa with respect to other members of the Heterandriini. The results further suggest that most tribe-level taxa of the Poeciliinae are not monophyletic, and that further work remains to resolve the evolutionary relationships of this group.


PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e9352
Author(s):  
Barbara Maria Patoleta ◽  
Joanna Gardzińska ◽  
Marek Żabka

The study is based on new material from the collections of the Naturalis Biodiversity Centre in Leiden (RNHM) and the Hungarian Natural History Museum (HNHM) and addresses issues in two genera: Epeus Peckham & Peckham, 1886 and Ptocasius Simon, 1885 from Thailand. Both genera are of Asian/Indomalayan origin, the latter with a diversity hotspot in the subtropical valleys of the Himalayas. Based on morphological data, we propose three new species of Epeus (Epeus daiqini sp. nov. (♂♀), Epeus pallidus sp. nov. (♀), Epeus szirakii sp. nov. (♀)) and two new species of Ptacasius (Ptocasius metzneri sp. nov. (♂♀) and Ptocasius sakaerat sp. nov. (♀)). Additionally, we redescribed E. tener (Simon, 1877) and added photographs of morphological characters. The genus Ptocasius is redefined due to the inclusion of 37 species, previously included in Yaginumaella Prószyński, 1979. Relationships and distribution of both genera are discussed in reference to molecular, morphological and distributional data, published by other authors in recent years.


2021 ◽  
Vol 912 (1) ◽  
pp. 012103
Author(s):  
Elimasni ◽  
R A Nasution

Abstract Abstrak. Loquat (Eriobotrya japonica Lindl.) is a flowering plant that belongs to the Rosacea family. The loquat has many health benefits. Cultivation and information about loquat plants in Indonesia are still limited, so they are rarely found and known by the public. Limited information and data regarding loquat plants is also an obstacle to the development of loquat plants. Research on loquat plants aims to analyze the morphological characters in three districts, namely, Karo, Dairi, and Simalungun districts. This research was conducted using a descriptive method. The analysis of the morphological characteristics of loquat plants using morphological data scoring into binary data. The similarity between individuals was analyzed using clusters with the NTSYS program version 2.0 with the UPGMA method of the SimQual function. Morphological Observation Results Loquat plants (Eriobotrya japonica Lindl.) in Karo, Dairi, and Simalungun Districts have uniform characters in the morphology of stems, leaves, and flowers. However, the observed fruit and seed morphology showed different characters. Different characters exist in the shape of the fruit and seeds. The morphological similarity level of loquat plants was grouped at a similarity coefficient value of 95%. Clusters I and II have the highest similarity with a coefficient value of 100%. Cluster III has the lowest similarity with a coefficient value of 97%.


2021 ◽  
Vol 80 (2) ◽  
Author(s):  
Mostafa Ebadi ◽  
Rosa Eftekharian

Senecio vulgaris L., an annual herb belonging to the Asteraceae, is widely distributed in different regions of the world. There is no information on the intraspecific variations of the morphological and molecular features of this species. In the present investigation, we studied the morphological and genetic diversity of 81 accessions of S. vulgaris collected from 10 geographical populations. Eleven inter simple sequence repeat (ISSR) primers were used for the examination of genetic variations among the populations. Analysis of molecular variance (AMOVA) and GST analyses revealed significant differences among the investigated populations. A significant correlation between genetic distance and geographical distance was revealed by the Mantel test. However, reticulation analysis indicated the occurrence of gene flow among most of the populations studied. Principal component analysis (PCA) plot showed that the number of capitula, length of the cauline leaf and plant height were the most variable morphological characters. Principal coordinates analysis (PCoA) plot revealed two groups of populations, according to molecular and morphological data. The results suggested the existence of possible intraspecific taxonomic ranks within this species.


Phytotaxa ◽  
2013 ◽  
Vol 92 (2) ◽  
pp. 25
Author(s):  
XIAO-FENG JIN ◽  
BING-YANG DING ◽  
YING-YING ZHOU ◽  
SHUI-HU JIN ◽  
WANG-WEI YANG

In this paper, we present a revision of the Rhododenron taipaoense complex, including R. taipaoense and eight other named species, based on literature survey, field collections and observations, inspection of herbarium specimens, statistical analysis of morphological characters, and SEM observation of seed shape and testa. We evaluated all characters that have previously been used to diagnose these species: indumentum of young shoots and abaxial surfaces of leaves; filament dimensions; style base; leaf color, size, and apex shape; flower number per inflorescence; corolla length; and length of the stamen and pistil. Cluster analysis of 146 individuals showed that individuals from different populations are interdigitated, irrespective of traditional taxonomic limits. Analysis of morphological data using principal coordinate analysis (PCoA) likewise shows a continual gradation between populations, rather than disjunctures between named species. Consequently, only one species is recognized in the present paper, and R. apricum, R. falcinellum (R. apricum var. falcinellum), R. florulentum, R. hepticum, R. piceum, R. rufulum, R. spadiceum, and R. rufoindumentum (nom. nud.) are all reduced to synonyms of R. taipaoense.


Zootaxa ◽  
2004 ◽  
Vol 680 (1) ◽  
pp. 1 ◽  
Author(s):  
ARNE NYGREN

Autolytinae is revised based on available types, and newly collected specimens. Out of 170 nominal species, 18 are considered as incertae sedis, 43 are regarded as junior synonyms, and 25 are referred to as nomina dubia. The relationships of Autolytinae is assessed from 51 morphological characters and 211 states for 76 ingroup-taxa, and 460 molecular characters from mitochondrial 16S rDNA and nuclear 18S rDNA for 31 ingroup-taxa; outgroups include 12 non-autolytine syllid polychaetes. Two analyses are provided, one including morphological data only, and one with combined morphological and molecular data sets. The resulting strict consensus tree from the combined data is chosen for a reclassification. Three main clades are identified: Procerini trib. n., Autolytini Grube, 1850, and Epigamia gen. n. Proceraea Ehlers, 1864 and Myrianida Milne Edwards, 1845 are referred to as nomen protectum, while Scolopendra Slabber, 1781, Podonereis Blainville, 1818, Amytis Savigny, 1822, Polynice Savigny, 1822, and Nereisyllis Blainville, 1828 are considered


Zootaxa ◽  
2018 ◽  
Vol 4535 (1) ◽  
pp. 1 ◽  
Author(s):  
JÖRG FREYHOF ◽  
ESRA BAYÇELEBİ ◽  
MATTHIAS GEIGER

The diversity of Cobitis in the Middle East is reviewed, resulting in the recognition of 30 species, of which eight are described herein as new. Two species, C. amphilekta and C. kellei, seem to be extinct. Hypotheses on species-level diversity derived from distance and Poisson tree process analyses of DNA barcode data are tested against morphometric and morphological characters including colour patterns. For species pairs separated by small K2P distances in COI sequence data we follow a practitioner-oriented diagnostic species concept, in which we recognise species only if differentiated morphologically (including by colour pattern). For all 30 species we provide diagnoses and identification keys. Cobitis afifeae, new species, from the Büyük Menderes River drainage in the Aegean Sea basin, is distinguished by having two laminae circularis in the male, a row of blotches below Z4, a small, roundish or comma-shaped black spot at the upper caudal-fin base, and elevated mental lobes. Cobitis aliyeae, new species, from the lower Seyhan and Ceyhan River drainages, is distinguished by having two laminae circularis in the male, the blotches in Z2 and Z4 anterior to the dorsal-fin origin usually well separated from each other, and the pigmentation in Z1 well distinguished from the pigmentation in Z2. Cobitis anabelae, new species, from the lower Orontes River drainage, is distinguished by having two laminae circularis in the male, the pigmentation in Z2 formed by small, brown spots, always much smaller than blotches in Z3, much smaller than the pupil diameter, Z2 and Z3 well separated, and no pigmentation below Z4. Cobitis erkakanae, new species, from the Gölbasi Lakes, adjacent to the Ceyhan River drainage, is distinguished by having two laminae circularis in the male, no blotches below Z4, the blotches in Z2 and Z4 being horizontally elongated and often fused with adjacent ones, and the caudal fin with 4–6 wide, regularly-shaped, brown bands. Cobitis emrei, new species, from the Lake Sapanca basin is distinguished by having one lamina circularis in the male, a large black spot at the upper caudal-fin base, and Z3 fully covered by very small spots forming a sand-like pattern. Cobitis joergbohleni, new species, from the Sultan marshes in Central Anatolia is distinguished by having two laminae circularis in the male, and the flank colour pattern being completely disorganised, not following the Gambetta zones. Cobitis pirii, new species, from the endorheic Lake Eğirdir basin and the Mediterranean Aksu and Köprü Rivers, is distinguished by having two laminae circularis in the male, a simple external part of the suborbital spine and two distinct rows of small blotches in Z4, one along the lateral midline and one distinctly below. Cobitis troasensis, new species, from the Tuzla River drainage, is distinguished by having one lamina circularis in the male and 25–36 small, comma-shaped brown blotches in Z4. A lectotype is designated for Cobitis battalgilae. As First Revisers, priority is given to Cobitis fahireae over C. kurui. Cobitis damlae and C. kurui are treated as synonyms of C. fahireae. Cobitis strumicae and C. taenia are recorded for the first time from Anatolia and C. saniae is newly documented from the Black Sea basin in Georgia. The Poisson tree process analysis of COI data proposed 31 groups, most of which could be distinguished by morphological characters. Cobitis troasensis is described based on morphological data alone.  


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