scholarly journals Intraspecific variation in the Cambrian: new observations on the morphology of the Chengjiang euarthropod Sinoburius lunaris

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Michel Schmidt ◽  
Yu Liu ◽  
Xianguang Hou ◽  
Joachim T. Haug ◽  
Carolin Haug ◽  
...  
Keyword(s):  
Intraspecific Variation ◽  
Southwest China ◽  
3D Models ◽  
Morphological Characters ◽  
Open Questions ◽  
New Findings ◽  
Unique Shape ◽  
Variable Species ◽  
Chengjiang Biota ◽  
3D Software

Abstract Background The Chengjiang biota from southwest China (518-million-years old, early Cambrian) has yielded nearly 300 species, of which more than 80 species represent early chelicerates, crustaceans and relatives. The application of µCT-techniques combined with 3D software (e.g., Drishti), has been shown to be a powerful tool in revealing and analyzing 3D features of the Chengjiang euarthropods. In order to address several open questions that remained from previous studies on the morphology of the xandarellid euarthropod Sinoburius lunaris, we reinvestigated the µCT data with Amira to obtain a different approach of visualization and to generate new volume-rendered models. Furthermore, we used Blender to design 3D models showing aspects of intraspecific variation. Results New findings are: (1) antennulae consist of additional proximal articles that have not been detected before; (2) compared to other appendages, the second post-antennular appendage has a unique shape, and its endopod is comprised of only five articles (instead of seven); (3) the pygidium bears four pairs of appendages which are observed in all specimens. On the other hand, differences between specimens also have been detected. These include the presence/absence of diplotergites resulting in different numbers of post-antennular appendages and tergites and different distances between the tip of the hypostome and the anterior margin of the head shield. Conclusions Those new observations reveal intraspecific variation among Chengjiang euarthropods not observed before and encourage considerations about possible sexual dimorphic pairs or ontogenetic stages. Sinoburius lunaris is a variable species with respect to its morphological characters, cautioning that taxon-specific variabilities need to be considered when exploring new species.

New Findings on Scrophularia sect. Mimulopsis (Scrophulariaceae) from Iran

2019 ◽  
Vol 27 (4) ◽  
pp. 238-247
Author(s):  
Massoud Ranjbar ◽  
Narges Rahchamani
Keyword(s):  
New Species ◽  
Pollen Morphology ◽  
Conservation Status ◽  
Morphological Characters ◽  
Northern Iran ◽  
Distribution Maps ◽  
New Findings ◽  
Tehran Province ◽  
Micromorphological Characters ◽  
A New Species

Scrophularia dianatnejadii Ranjbar & Rahchamani, a new species from Tehran Province in northern Iran, is described and illustrated. It is closely related to S. amplexicaulis Benth. and shares with it some diagnostic morphological characters such as habit, plant indument, phyllotaxy, and corolla shape and color. Both species are placed in Scrophularia L. sect. Mimulopsis Boiss. Macro- and micromorphological characters of the two are examined and compared. Pollen morphology of these species is investigated using SEM. Detailed descriptions, illustrations, distribution maps, and conservation status of both species are provided.

scholarly journals A new species ofScutellaria(Scutellarioideae, Lamiaceae) from Sichuan Province in southwest China

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3624 ◽  
Author(s):  
Fei Zhao ◽  
En-De Liu ◽  
Hua Peng ◽  
Chun-Lei Xiang
Keyword(s):  
New Species ◽  
Southwest China ◽  
Morphological Characters ◽  
Sichuan Province ◽  
Pollen Grain ◽  
Yellow Corolla ◽  
A New Species

Scutellaria wuana, a new species discovered from a xeric valley in Muli County of Sichuan Province in southwest China, is described and illustrated. Morphologically, the new species shares similarities withS. mairei, but can be readily distinguished by a suite of morphological characters including a white-pubescent erect stem, conspicuous leaf petioles, and a yellow corolla with a trapeziform lower-middle lip lobe. The habitat and distribution ofS. wuanaare also distinctive. The position of the new species withinScutellariais examined in a phylogenetic context using the nuclear ribosomal internal and external transcribed spacers. Additionally, we examine leaf epidermal and pollen grain micromorphology of the new species and putative relatives.

Morphometric studies of the Euphorbia esula group (Euphorbiaceae) in North America

1990 ◽  
Vol 68 (9) ◽  
pp. 1978-1988 ◽  
Author(s):  
C. W. Crompton ◽  
A. E. Stahevitch ◽  
W. A. Wojtas
Keyword(s):  
North America ◽  
Morphological Characters ◽  
Leafy Spurge ◽  
Principal Coordinate Analysis ◽  
Euphorbia Esula ◽  
Eastern North America ◽  
Single Variable ◽  
Authentic Material ◽  
Variable Species ◽  
Euphorbia Cyparissias

Leafy spurge and cypress spurge are important weeds of pastures and unimproved rangeland in western and eastern North America, respectively. Taxonomists disagree as to whether leafy spurge is a single variable species or an aggregate of two or more species. Morphometric techniques (clustering by incremental sum of squares and principal coordinate analysis) were used to analyze relationships in leafy spurge and its allies. On the basis of studying 26 morphological characters found in 200 collections representing 32 putative taxa, we concluded that in North America only four species should be recognized, namely, Euphorbia agraria Bieb., Euphorbia cyparissias L., Euphorbia esula L., and Euphorbia ×pseudoesula Schur. A key to these taxa is provided. No authentic material of Euphorbia lucida Waldst. & Kitt. and Euphorbia salicifolia Host was found from this continent in the collections we examined.

3D Simulation of Second-Order Surfaces

2016 ◽  
Vol 4 (4) ◽  
pp. 48-59 ◽  
Author(s):  
Ремонтова ◽  
Lyudmila Remontova ◽  
Нестеренко ◽  
Leonid Nesterenko ◽  
Бурлов ◽  
...  
Keyword(s):  
Computer Technology ◽  
3D Model ◽  
System Development ◽  
3D Models ◽  
Second Order ◽  
Descriptive Geometry ◽  
Hyperbolic Paraboloid ◽  
Graphic Editor ◽  
3D Software ◽  
High Educational

This paper’s material is destined for high educational institutions’ graduate students and teachers whose professional activity is connected with problems of descriptive geometry and engineering graphics teaching improving on the basis of modern computer technology. The paper will be useful to students of technical universities in their further understanding the course of descriptive geometry and inoculation them an interest in their personal geometric and graphic training, without which a quality engineering creativity is impossible. The paper focuses on use of KOMPAS-3D software possibilities which enables solution of nearly all educational, as well as professional engineering and graphics problems. At the same time, the promotion of domestic IT-product in educational area is an urgent task, arising from the problem of technical education at the present stage of public education’s system development. A number of examples related to solution of spatial problems connected with second-order surfaces simulation have been considered. On the basis of descriptive geometry’s laws applicable to surface problems, a feature of their solution and display on computer screen has been illustrated. For example, in the graphic editor KOMPAS-3D there is the Ellipse command, but there are no Hyperbola or Parabola commands. But without these curves it is impossible to create a 3D model of hyperboloid (one- or two-sheet), paraboloid, or hyperbolic paraboloid. To create these curves it has been proposed to use conics of circular cone, canonical or parametric equations of hyperbolas and parabolas. For each of these options the examples of second-order surfaces 3D models creation have been considered.

Mechanism of zeolites crystal growth: new findings and open questions

CrystEngComm ◽  
2016 ◽  
Vol 18 (5) ◽  
pp. 650-664 ◽  
Author(s):  
Julien Grand ◽  
Hussein Awala ◽  
Svetlana Mintova
Keyword(s):  
Crystal Growth ◽  
Open Questions ◽  
New Findings

scholarly journals New data to the knowledge of Gaeolaelaps mites (Acari: Mesostigmata: Laelapidae)

Acarologia ◽  
2018 ◽  
Vol 58 (3) ◽  
pp. 710-734
Author(s):  
Alireza Nemati ◽  
Dariusz J. Gwiazdowicz ◽  
Arsalan Khalili-Moghadam
Keyword(s):  
Intraspecific Variation ◽  
Morphological Changes ◽  
Morphological Difference ◽  
Morphological Characters ◽  
Type Material ◽  
Taxonomic Confusion ◽  
Morphological Differences ◽  
Distinguishing Features

The present paper is devoted to the study of some morphological changes in the laelapid genus Gaeolaelaps, based on observations on G. queenslandicus (Womersley, 1956), G. angustus (Karg, 1965) and G. tripodiger (Berlese, 1916) [new comb]. According to our observations on the type material of G. angustus, previous redescription of G. queenslandicus (sensu Costa 1966, based on holotype), specimens of this species from Australia and numerous specimens from Iran identified as either G. angustus or G. queenslandicus, notable variations were observed in some morphological characters, which had previously been considered as distinguishing features between the two species. Our analysis indicates that these morphological differences represent intraspecific variation, and therefore the two species names are synonyms. Furthermore, observation of type material of G. tripodiger shows that the two first mentioned species are junior synonyms of G. tripodiger. The original descriptions of G. trifurcatus (Wang and Li, 1965) [new comb.] and G. trifurcatoides (Yan and Ma, 1999) ([new comb.] show no authentic morphological difference from G. tripodiger and those are also junior synonyms of the later. The oldest available name for this species is Gaeolaelaps tripodiger. However, that name is almost unknown, and to use it as a valid name would cause taxonomic confusion. Therefore, we continue to use the widely known name Gaeolaelaps queenslandicus for this species, in the interests of stability.

scholarly journals 3D survey for the archaeological study and virtual reconstruction of the “Sanctuary of Isis” in the ancient Lilybaeum (Italy)

2020 ◽  
Vol 11 (22) ◽  
pp. 1 ◽  
Author(s):  
Leonarda Fazio ◽  
Mauro Lo Brutto
Keyword(s):  
Three Dimensional ◽  
Archaeological Site ◽  
3D Models ◽  
Archaeological Remains ◽  
Archaeological Heritage ◽  
Digital Reconstruction ◽  
3D Environment ◽  
3D Data ◽  
Open Questions ◽  
Virtual Reconstruction

<p class="VARKeywords">In recent years, the use of three-dimensional (3D) models in cultural and archaeological heritage for documentation and dissemination purposes has increased. New geomatics technologies have significantly reduced the time spent on fieldwork surveys and data processing. The archaeological remains can be documented and reconstructed in a digital 3D environment thanks to the new 3D survey technologies. Furthermore, the products generated by modern surveying technologies can be reconstructed in a virtual environment on effective archaeological bases and hypotheses coming from a detailed 3D data analysis. However, the choice of technologies that should be used to get the best results for different archaeological remains and how to use 3D models to improve knowledge and dissemination to a wider audience are open questions.</p><p class="VARKeywords">This paper deals with the use of terrestrial laser scanners and photogrammetric surveys for the virtual reconstruction of an archaeological site. In particular, the work describes the study for the 3D documentation and virtual reconstruction of the “Sanctuary of Isis” in <em>Lilybaeum,</em> the ancient city of Marsala (southern Italy). The "Sanctuary of Isis" is the only Roman sacred building known in this archaeological area. Based on the survey data, it has been possible to recreate the original volumes of the ancient building and rebuild the two best-preserved floors –a geometric mosaic and an <em>opus spicatum</em>– for a first digital reconstruction of the archaeological complex in a 3D environment.</p>

Chuanicosmetura gen. nov. of the tribe Meconematini (Orthoptera: Tettigoniidae) from southwest China and Chuanicosmetura emarginata (Liu, 2000) comb. nov.

Zootaxa ◽  
2021 ◽  
Vol 4981 (2) ◽  
pp. 393-397
Author(s):  
QI GUO ◽  
TAO WANG ◽  
FU-MING SHI
Keyword(s):  
Southwest China ◽  
Morphological Characters

Chuanicosmetura gen. nov. (Orthoptera: Tettigoniidae: Meconematinae) is established based on Chuanicosmetura emarginata (Liu, 2000) comb. nov. In this paper, this species was redescribed, and the male is firstly reported. Illustrations of important morphological characters are provided. 

New and known species of Nothotylenchus Thorne, 1941 (Nematoda: Anguinidae) from Iran with an updated list of species

Zootaxa ◽  
2020 ◽  
Vol 4729 (4) ◽  
pp. 482-500
Author(s):  
KOBRA HASHEMI ◽  
AKBAR KAREGAR
Keyword(s):  
New Species ◽  
Intraspecific Variation ◽  
Body Length ◽  
Morphological Characters ◽  
Identification Key ◽  
Valid Species ◽  
Morphometric Data ◽  
Pharyngeal Bulb ◽  
Two New Species

During a survey conducted during 2013–2017, five known and two new species of Nothotylenchus Thorne, 1941 were collected from the southern provinces of Iran. N. brzeskii n. sp. is characterised by a body length of 774–922 µm, lateral fields with four incisures, delicate, short stylet (7–8 µm) with small rounded knobs, pyriform, offset or slightly overlapping basal pharyngeal bulb, posterior vulva position (V = 83.4–84.4), short PUS (5–10 µm), spicules 20.5–23 µm long, and thick tail with rounded to dull terminus. N. siddiqi n. sp. is characterised by a body length of 573–645 µm, six to nine incisures in lateral fields, delicate, short stylet (6.5–7.5 µm) with rounded knobs, pyriform or slightly elongate and offset basal pharyngeal bulb, V = 79.3–81.0, PUS = 26.5–40 µm, short spicules = 14.5–16.5 µm, and tail with rounded terminus. Morphometric data of the studied species are presented and intraspecific variation of their morphometrics and morphological characters is discussed. The list of world Nothotylenchus species is updated, and a dichotomous identification key and an updated tabular compendium for 41 valid species are provided. 

Sign in / Sign up

Export Citation Format

Share Document