scholarly journals Molecular phylogeny of Lytorhynchus diadema (Reptilia, Colubridae) populations in Saudi Arabia

Herpetozoa ◽  
2021 ◽  
Vol 34 ◽  
pp. 271-276
Author(s):  
Ahmed Alshammari ◽  
Ahmed Badry ◽  
Salem Basuis ◽  
Adel A. Ibrahim ◽  
Eman El-Abd

This study presents the molecular phylogenetic relationships among Lytorhynchus diadema (Duméril, Bibron & Duméril, 1854) populations in Saudi Arabia relative to populations from Africa and Asia. This phylogenetic analysis was based on mitochondrial 16S and 12S rRNA partial gene fragments using Neighbor-joining, Maximum Parsimony, and Bayesian methods. The results strongly support the monophyly of Lytorhynchus based on two concatenated genes and the 12S rRNA gene separately. Also, a significant separation is observed between the Arabian samples from Saudi Arabia, Yemen, and Oman, and the African populations from Egypt, Tunisia, and Morocco.

2021 ◽  
Vol 8 (4) ◽  
pp. 55
Author(s):  
Feng Yu ◽  
Bo Liu ◽  
Shulei Chen ◽  
Ziwen Yi ◽  
Xianyong Liu ◽  
...  

A 5-year-old Mongolian mare (Equus caballus Linnaeus, 1758) was observed to have corneal opacity and excessive ocular discharge. An ophthalmic examination revealed a moving thread-like cylindrical worm in the anterior chamber of the right eye. The parasite was successfully removed surgically. The worm was observed under light microscopy and confirmed as Setaria digitata by 12S rRNA gene amplification and sequencing. Phylogenetic analysis demonstrated similarity with Setaria digitata in the National Center for Biotechnology Information (NCBI) GenBank database isolated from other Asian countries. This report is the first confirmed case of equine ocular setariasis by molecular diagnosis in China, which may indicate its presence in livestock and promote research on its epidemiology.


1996 ◽  
Vol 351 (1337) ◽  
pp. 349-360 ◽  

Despite extensive studies on the ecology and evolution of the freshwater microcrustacean Daphnia , there is little understanding of the evolutionary history of the genus. Past attempts at reconstructing phylogenetic relationships among Daphnia species have been highly controversial, mainly because of the poor taxonomy of the genus. However, following a revised taxonomy of the daphniid fauna of North America, we conducted a comprehensive appraisal of systematic relationships within the genus through the analysis of sequence diversity in 503 b.p. of the 12S rRNA gene of the mtDNA. The large sequence divergence among its 34 North American members indicates that the genus Daphnia originated during the Mesozoic, even though many lineages exhibit extreme morphological stasis. Results from both cladistic and phenetic analyses indicate the presence of three subgenera comprised of 15 species complexes. Only four of these lineages have shown active speciation over the past 3 Ma, suggesting that cladogenesis in the genus has been constrained. Our study also reveals that interspecific hybridization occurs between taxa which show very large sequence divergence (up to 14%), suggesting that reproductive isolation within the genus evolves slowly.


2008 ◽  
Vol 98 (5) ◽  
pp. 499-507 ◽  
Author(s):  
H.C. Zhang ◽  
G.X. Qiao

AbstractThree traditional tribes of Fordini, Pemphigini and Eriosomatini comprise Pemphiginae, and there are two subtribes in Fordini and Pemphigini, respectively. Most of the species in this subfamily live heteroecious holocyclic lives with distinct primary host specificity. The three tribes of Pemphigini (except Prociphilina), Eriosomatini and Fordini use three families of plants, Salicaceae (Populus), Ulmaceae (Ulums) and Anacardiaceae (Pistacia and Rhus), as primary hosts, respectively, and form galls on them. Therefore, the Pemphigids are well known as gall makers, and their galls can be divided into true galls and pseudo-galls in type. We performed the first molecular phylogenetic study of Pemphiginae based on molecular data (EF-1α sequences). Results show that Pemphiginae is probably not a monophylum, but the monophyly of Fordini is supported robustly. The monophyly of Pemphigini is not supported, and two subtribes in it, Pemphigina and Prociphilina, are suggested to be raised to tribal level, equal with Fordini and Eriosomatini. The molecular phylogenetic analysis does not show definite relationships among the four tribes of Pemphiginae, as in the previous phylogenetic study based on morphology. It seems that the four tribes radiated at nearly the same time and then evolved independently. Based on this, we can speculate that galls originated independently four times in the four tribes, and there is no evidence to support that true galls are preceded by pseudo-galls, as in the case of thrips and willow sawflies.


2002 ◽  
Vol 22 (2) ◽  
pp. 174-183 ◽  
Author(s):  
Antoinette C. van der Kuyl ◽  
Donato L. Ph. Ballasina ◽  
John T. Dekker ◽  
Jolanda Maas ◽  
Ronald E. Willemsen ◽  
...  

2020 ◽  
Author(s):  
Abigail Hui En Chan ◽  
Kittipong Chaisiri ◽  
Serge Morand ◽  
Naowarat Saralamba ◽  
Urusa Thaenkham

Abstract Background Molecular advances have accelerated our understanding of nematode systematics and taxonomy. However, comparative analyzes between various genetic markers have led to discrepancies in nematode phylogenies. This study aimed to evaluate the suitability of using mitochondrial 12S and 16S ribosomal RNA genes for nematode molecular systematics. Methods To study the suitability of mitochondrial 12S and 16S ribosomal RNA genes as genetic markers for nematode molecular systematics, we compared them with the other commonly used genetic markers, nuclear internal transcribed spacer 1 and 2 regions, nuclear 18S and 28S ribosomal RNA genes, and mitochondrial cytochrome c oxidase subunit 1 gene. After that, phylum-wide primers for mitochondrial 12S and 16S ribosomal RNA genes were designed, and parasitic nematodes of humans and animals from 75 taxa with 21 representative species were inferred through phylogenetic analyzes. Phylogenetic analyzes were carried out using maximum likelihood and Bayesian inference algorithms. Results The phylogenetic relationships of nematodes based on the mitochondrial 12S rRNA gene supported the monophyly of nematodes in clades I, IV, and V, reinforcing the potential of this gene as a genetic marker for nematode systematics. In contrast, the mitochondrial 16S rRNA gene only supported the monophyly of clades I and V, providing evidence that the 12S rRNA gene is more suitable for nematode molecular systematics. In this study, subclades of clade III containing various nematode families were not monophyletic when the 16S or 12S rRNA gene was used as the genetic marker. This is similar to the phylogenetic relationship revealed by previous studies using whole mitochondrial genomes as genetic markers. Conclusions This study supports the use of the 12S rRNA gene as a genetic marker for studying the molecular systematics of nematodes to understand intra-phyla relationships. Phylum-wide primers for nematodes using mitochondrial ribosomal genes were prepared, which may enhance future studies. Furthermore, sufficient genetic variation in the mitochondrial 12S and 16S rRNA genes between species also allowed for accurate taxonomy to species level, revealing the potential of these two genes as genetic markers for DNA barcoding.


Sign in / Sign up

Export Citation Format

Share Document