scholarly journals Molecular variation and phylogenetic status of ponyfish (Perciformes: Leiognathidae) in Karaikal, South India

2020 ◽  
Vol 12 (2) ◽  
pp. 251-257
Author(s):  
Firudoz BANU ◽  
Vellaichamy RAMANADEVI ◽  
Gunasekar SHALINI ◽  
Muthusamy THANGARAJ

The family Leiognathidae, commonly known as ponyfish and they are mainly classified by mouth morphology. In this study, genetic variation and phylogenetic relationships among nine genera and 13 species of Leiognathidae, inferred from Cytochrome Oxydase I gene. The Neighbour Joining tree showed the paraphyly of the studied species form genus Secutor and monophyly status all the other eight genera. Leiognathus equulus is occupying a basal branch of the family NJ tree. The highest genetic distance (0.349) showed between Eubleekeria and Nuchequula. The lowest genetic distance (0.007) showed between the genus Nuchequula and Leiognathus. Among the nine genera, very less nucleotide diversity (π= 0.1100) was in Secutor and higher value (π = 0.7558) was recorded in Leiognathus. The Tajima’s test statistic (D) value was positive, so, the entire genus is in balancing selection.  

Genes ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 29
Author(s):  
Lilia González-Cerón ◽  
José Cebrián-Carmona ◽  
Concepción M. Mesa-Valle ◽  
Federico García-Maroto ◽  
Frida Santillán-Valenzuela ◽  
...  

Plasmodium vivax Cysteine-Rich Protective Antigen (CyRPA) is a merozoite protein participating in the parasite invasion of human reticulocytes. During natural P. vivax infection, antibody responses against PvCyRPA have been detected. In children, low anti-CyRPA antibody titers correlated with clinical protection, which suggests this protein as a potential vaccine candidate. This work analyzed the genetic and amino acid diversity of pvcyrpa in Mexican and global parasites. Consensus coding sequences of pvcyrpa were obtained from seven isolates. Other sequences were extracted from a repository. Maximum likelihood phylogenetic trees, genetic diversity parameters, linkage disequilibrium (LD), and neutrality tests were analyzed, and the potential amino acid polymorphism participation in B-cell epitopes was investigated. In 22 sequences from Southern Mexico, two synonymous and 21 nonsynonymous mutations defined nine private haplotypes. These parasites had the highest LD-R2 index and the lowest nucleotide diversity compared to isolates from South America or Asia. The nucleotide diversity and Tajima’s D values varied across the coding gene. The exon-1 sequence had greater diversity and Rm values than those of exon-2. Exon-1 had significant positive values for Tajima’s D, β-α values, and for the Z (HA: dN > dS) and MK tests. These patterns were similar for parasites of different origin. The polymorphic amino acid residues at PvCyRPA resembled the conformational B-cell peptides reported in PfCyRPA. Diversity at pvcyrpa exon-1 is caused by mutation and recombination. This seems to be maintained by balancing selection, likely due to selective immune pressure, all of which merit further study.


Genetics ◽  
2000 ◽  
Vol 155 (2) ◽  
pp. 863-872 ◽  
Author(s):  
Helmi Kuittinen ◽  
Montserrat Aguadé

AbstractAn ~1.9-kb region encompassing the CHI gene, which encodes chalcone isomerase, was sequenced in 24 worldwide ecotypes of Arabidopsis thaliana (L.) Heynh. and in 1 ecotype of A. lyrata ssp. petraea. There was no evidence for dimorphism at the CHI region. A minimum of three recombination events was inferred in the history of the sampled ecotypes of the highly selfing A. thaliana. The estimated nucleotide diversity (θTOTAL = 0.004, θSIL = 0.005) was on the lower part of the range of the corresponding estimates for other gene regions. The skewness of the frequency spectrum toward an excess of low-frequency polymorphisms, together with the bell-shaped distribution of pairwise nucleotide differences at CHI, suggests that A. thaliana has recently experienced a rapid population growth. Although this pattern could also be explained by a recent selective sweep at the studied region, results from the other studied loci and from an AFLP survey seem to support the expansion hypothesis. Comparison of silent polymorphism and divergence at the CHI region and at the Adh1 and ChiA revealed in some cases a significant deviation of the direct relationship predicted by the neutral theory, which would be compatible with balancing selection acting at the latter regions.


Parasitology ◽  
1986 ◽  
Vol 92 (1) ◽  
pp. 245-252 ◽  
Author(s):  
R. Mad Havi ◽  
J. V. Ramanjaneyulu

SUMMARYThe karyotype ofTransversotrema patia1enconsists of 10 pairs of chromosomes (2n= 20) of which 5 pairs are metacentrics and 5 pairs are submetacentrics. The chromosomes are large and range in size from 5 to 12 μm. The total chromosome length of the diploid complement is 16783 μm. Stages of spermatogenesis including the two gonial divisions and two reduction divisions leading to production of spermatozoa occur in cercarial embryos inside snail tissue, while the maturation divisions of the ovum occur in eggs freshly liberated by the fluke. The chiasma frequency is high, being 3888/cell and 388/bivalent. Cytological data indicate an independent phylogenetic status for the family Transversotrematidae.


1979 ◽  
Vol 25 ◽  
pp. 504-533

Thiruvenkata Rajendra Seshadri was born on 3 February 1900 in the small town of Kulitalai lying on the bank of the Kaveri, one of the seven sacred rivers of India, and situated in the Tiruchy district of South India. This district formed a part of the Madras Presidency of pre-independent India and is now a part of the state of Tamil Nadu of the Indian Republic. His father, Thiruvengadatha Iyengar, was a teacher in a local school; his mother was Namagiri Ammal, and T. R. Seshadri was the third of five sons who were the only children of the marriage. The family was deeply religious, and this influence was dominant throughout T. R. Seshadri’s life, not only in his personal attitudes but also in his complete dedication to his work.


1982 ◽  
Vol 10 (1) ◽  
pp. 90-97
Author(s):  
K.S. Susan Oorjitham

AbstractThe largest group of Indians in West Malaysia are the Tamil-speaking Hindus who originate from South India, particularly from Tamilnad. According to S. Arasaratnam, not only are 80% of Indians in Malaysia Tamil speakers but a vast majority of them are also Hindus.1 It is further established that the majority of this group are members of the working class, either in the plantation or in the urban sectors. The family structures of these Tamil working-class families originate basically from the traditional Indian family structure of India. This traditional Indian family structure was maintained in the "conducive" environment of ethnic isolation, found in the plantations. Since my purpose is to study changes in the family structure, Tamil working-class families in an urban environment were selected. It is expected that some changes in family values and structures have occurred among this group of Indians in West Malaysia.


Zootaxa ◽  
2019 ◽  
Vol 4674 (4) ◽  
pp. 426-438
Author(s):  
CHENGLONG CAO ◽  
SIYAO HUANG ◽  
YONGQIANG XU ◽  
HAOMIN WU ◽  
TIANPENG CHEN ◽  
...  

The specimens of the family Hesperiidae collected from Tibet during 2016–2018 are identified using morphology. COI sequences of 76 individuals are newly obtained. The result of our morphological study is congruent with COI gene analyses. Maximum likehood (ML) and Bayesina inferences (BI) analyses reveal that individuals identified morphologically as the same species cluster cohesively. The minimum interspecific genetic distance is 1.7% between Halpe aucma and H. filda, and the genetic distance between conspecific individuals ranged from 0 to 0.2% for the genus Halpe. A total of 51 species are recognized, and six of them, Celaenorrhinus consanguineus Leech, 1891, Barca bicolor (Oberthür, 1896), Aeromachus propinquus Alphéraky, 1897, Pedesta bivitta (Oberthür, 1886), Baoris penicillata chapmani Evans, 1937, and Ochlodes brahma Moore, 1878, are reported from Tibet for the first time, and the last species is new to China. 


Zootaxa ◽  
2019 ◽  
Vol 4603 (2) ◽  
pp. 377 ◽  
Author(s):  
RALF BRITZ ◽  
V.K. ANOOP ◽  
NEELESH DAHANUKAR ◽  
RAJEEV RAGHAVAN

Aenigmachanna gollum, new genus and species, is described from Kerala, South India. It is the first subterranean species of the family Channidae. It has numerous derived and unique characters, separating it from both the Asian Channa Scopoli and the African Parachanna Teugels & Daget. Uniquely among channids, A. gollum has a very slender (maximum body depth only 11.1–11.3% SL), eel-like body (head length 20.8–21.6% SL), large mouth (jaw length 60.4–61.1 % HL), 43–44 anal-fin rays, 83–85 scales in a lateral series, an unusual colour pattern and it lacks pored lateral-line scales on the body and body buoyancy. In addition, it is distinguished by its DNA barcode sequence, which is 15.8–24.2% divergent from other species of the family Channidae. Morphological modifications usually associated with a subterranean life, such as reduction of eyes and enhancement of non-visual senses (taste, smell, mechanosensory systems) are absent in A. gollum. However, it shares with subterranean fishes a slight reduction of its pigmentation in comparison to epigean channids.


1977 ◽  
Vol 55 (20) ◽  
pp. 2636-2651 ◽  
Author(s):  
Alastair D. Macdonald

Organogenesis of the male reproductive structures of Myrica pilulifera, Gale, and Comptonia is compared. In M. pilulifera, which has a compound inflorescence, one to three stamens form in the axils of second-order bracts of the partial inflorescence. In Gale and Comptonia, which do not have compound inflorescences, four stamens arise simultaneously on the flank of the apex of the second-order axis. It is concluded that this defines a floral condition for the family. A model is proposed which explains the probable development of the floral condition from the inflorescence state more adequately than existing floral concepts. Hence, speculation of the phylogenetic status of this family is avoided. Similarly, it is not necessary to debate notions of an angiospermous archetype. Recent knowledge of the family is collated from various disciplines such as taxonomy, anatomy, and palaeobotany to provide a framework for assessing the significance of the discussion of the ‘flower’ vs. ‘inflorescence’ problem.


Nematology ◽  
2009 ◽  
Vol 11 (6) ◽  
pp. 869-881 ◽  
Author(s):  
Natsumi Kanzaki ◽  
Robin M. Giblin-Davis ◽  
Rudolf H. Scheffrahn ◽  
Barbara J. Center ◽  
Kerrie A. Davies

Abstract A species of aphelenchoidid nematode was isolated from a subterranean termite, Cylindrotermes macrognathus, during a survey of termite-associated nematodes in a conserved forest in La Selva, Costa Rica. The nematode was morphologically intermediate between the families Aphelenchidae and Aphelenchoididae, i.e., the nematode had a true bursa supported by bursal limb-like genital papillae but lacked a clear pharyngeal isthmus. The molecular phylogenetic status of the new nematode among tylenchid, cephalobid, panagrolaimid, aphelenchid and aphelenchoidid genera was analysed based on ca 1.2 kb of SSU ribosomal DNA sequence and the inferred position was basal to the family Aphelenchoididae. It was clearly not part of the clade containing the genus Aphelenchus (=Aphelenchidae). This nematode is described herein as Pseudaphelenchus yukiae n. gen., n. sp., and the family definition of Aphelenchoididae is emended to include the unique morphological characters of this new genus. The molecular phylogenetic analysis supported the paraphyly of the three Aphelenchoidinae genera Aphelenchoides, Laimaphelenchus and Schistonchus and the monophyly of Ektaphelenchinae, Seinura (Seinurinae) and Noctuidonema (Acugutturinae). However, many more representatives are needed to resolve the family-genus level phylogeny of Aphelenchoididae.


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