A taxonomic revision of Gymnothorax undulatus (Anguilliformes: Muraenidae) in the Western Indian Ocean, with description of a new species

Zootaxa ◽  
2020 ◽  
Vol 4767 (1) ◽  
pp. 161-181
Author(s):  
YONELA SITHOLE ◽  
DAVID G. SMITH ◽  
MONICA MWALE ◽  
GAVIN GOUWS

The taxonomic status of the widely distributed Indo-Pacific undulated moray eel, Gymnothorax undulatus, is revised using morphological and genetics features. Ninety-seven specimens previously identified as G. undulatus were examined and their mitochondrial COI and 16S rRNA genes were analysed. The multivariate analysis of eight morphometric characters resulted in separation with little to no overlap among some geographic regions. These groupings explained more than 90% of the total variation, with 86.6% overall classification. Two color morphs were identified, and the South African population was described as new species, Gymnothorax elaineheemstrae n. sp., distinct from G. undulatus in having mottled and faintly reticulated color pattern, 134–136 total vertebrae and further confirmed by the genetic analysis of COI and 16S rRNA with > 0.1 genetic distance. The morphological and genetics results indicate that G. undulatus, previously treated as a single species, consists of more than one species. 

2017 ◽  
Vol 15 (5) ◽  
pp. 766-774 ◽  
Author(s):  
Mehdi Roshdi Maleki ◽  
Hossein Samadi Kafil ◽  
Naser Harzandi ◽  
Seyyed Reza Moaddab

Nontuberculous mycobacteria (NTM) have emerged as an important cause of opportunistic nosocomial infections. NTM has frequently been isolated from hospital water distribution systems. The aim of this study was to survey the risk of NTM infections and determine the prevalence of NTM species in the hospital water distribution systems in Tabriz, Iran. One hundred and twenty samples of water from different sources of Tabriz hospitals were collected. The samples were filtered through 0.45-µm pore size membranes and decontaminated with 0.01% cetylpyridinium chloride. The sediment was inoculated onto Lowenstein–Jensen medium and incubated for 8 weeks. For identification to the species level, partial sequence analysis of the hsp65 and 16S rRNA genes were used. NTM were detected in 76 (63.3%) of 120 samples. Potentially pathogenic mycobacteria and saprophytic mycobacteria were isolated. Mycobacterium gordonae was the only single species that was present in all types of water. The prevalence of NTM in Tabriz hospitals' water compared with many investigations on hospital waters was high. This indicates that the immunocompromised patients and transplant recipients are at risk of contamination which necessitates considering decontamination of water sources to prevent such potential hazards.


Zootaxa ◽  
2012 ◽  
Vol 3249 (1) ◽  
pp. 18 ◽  
Author(s):  
ANA P. MOTTA ◽  
SANTIAGO CASTROVIEJO-FISHER ◽  
PABLO J. VENEGAS ◽  
VICTOR G.D. ORRICO ◽  
JOSÉ M. PADIAL

We describe Dendropsophus frosti sp. nov. from lowland terra firme rainforests of the headwaters of the Amazon RiverBasin in Colombia and Peru. The new species is known from only two localities, the type locality near Leticia (Departa-mento Amazonas, Colombia, 04° 06' 24.2" S, 69° 56' 57.4" W; 103 m.a.s.l.), and the paratopotypic locality, Piedras in thePutumayo basin (Departamento Loreto, Peru, 02.79278° S, 72.91750° W; 90–170 m.a.s.l.). Maximum likelihood and par-simony analyses of 2436 aligned base pairs of the 12S and 16S rRNA genes recovered the new species as a member of D.parviceps group and sister to D. brevifrons. The new species is most closely related to D. parviceps, D. brevifrons, and D.koechlini, and it can be readily distinguished from these and all other members of the D. parviceps group by, among othercharacters, its plain dorsal light brown coloration, copper iris, plain immaculate pale yellow to white venter coloration, lack of flash marks on groin and axillae, and absence of white spots on lips.


2005 ◽  
Vol 49 (1) ◽  
pp. 434-437 ◽  
Author(s):  
Georg Conrads ◽  
Diane M. Citron ◽  
Ellie J. C. Goldstein

ABSTRACT Fourteen fluoroquinolone-resistant fusobacterial strains, originating from cats or dogs, were characterized by sequencing of the 16S-23S and 16S rRNA genes and DNA-DNA hybridization and were described as a new species, Fusobacterium canifelinum. All of the strains are intrinsically resistant (MIC, >4 g/ml) to levofloxacin and other fluoroquinolones. Compared to the quinolone resistance-determining region (gyrA) of the susceptible relative F. nucleatum, we found that Ser79 was replaced with leucine and Gly83 was replaced with arginine.


2021 ◽  
Vol 755 ◽  
Author(s):  
Didier VandenSpiegel ◽  
Arnaud Henrard ◽  
Aurore Mathys

A new millipede species of the genus Sechelleptus Mauriès, 1980 is described and illustrated from Mayotte Island, Indian Ocean. This new species, S. arborivagus sp. nov., found on trees, looks particularly similar to the sympatric S. variabilis VandenSpiegel & Golovatch, 2007, but is much larger and has a very different ecological behavior. Phylogenetic analyses based on a concatenated dataset of the COI and 16S rRNA genes and including nine species of Spirostreptidae (including Sechelleptus, Doratogonus Attems, 1914, Bicoxidens Attems, 1928 and Spirostreptus Brandt, 1833), strongly support the monophyly of Sechelleptus. Despite the similarity of their genitalia, the molecular analyses also reveal a clear-cut genetic divergence between S. arborivagus sp. nov. and S. variabilis (22.55% for COI and 6.63% for 16SrRNA) and further suggest the presence of a higher diversity within the genus Sechelleptus on Mayotte.


2011 ◽  
Vol 9 (1) ◽  
pp. 209-232 ◽  
Author(s):  
João Paulo C. B. da Silva ◽  
Marcelo R. de Carvalho

A taxonomic revision of two nominal species of freshwater stingrays of the genus Potamotrygon previously considered valid, Potamotrygon falkneri Castex & Maciel, 1963 and Potamotrygon castexi Castello & Yagolkowski, 1969, was conducted based on a detailed analysis of external and internal morphology, including a morphometric and meristic study of specimens from the recorded range of both species. The taxonomic status of the nominal species P. menchacai Achenbach, 1967, treated by previous authors as a junior synonym of P. falkneri, was also evaluated. These nominal species, which constitute what has been called the falkneri-castexi complex, were found to represent examples of chromatic variation present in a single species, given that intermediate patterns of coloration are common and the remaining characters analyzed are not consistent enough for separation at the specific level. Consequently, Potamotrygon falkneri is considered valid, whereas the nominal species Potamotrygon castexi and Potamotrygon menchacai are concluded to be junior synonyms of P. falkneri. Additionally, a putative new species is identified from the río Madre de Díos in Peru, which has some characters that do not correspond to P. falkneri. This species, known from few individuals, is here provisionally treated as Potamotrygon sp.


Zootaxa ◽  
2012 ◽  
Vol 3250 (1) ◽  
pp. 1 ◽  
Author(s):  
STEVEN M. GOODMAN ◽  
PETER J. TAYLOR ◽  
FANJA RATRIMOMANARIVO ◽  
STEVEN R. HOOFER

Using molecular genetics, male sexual organ morphology (baculum), and cranio-dental characters, we describe a new spe-cies of the genus Neoromicia from Madagascar, N. robertsi sp. nov. It is presumed to be endemic to the island and isknown from three specimens taken in montane areas of the eastern central region. The new species shows 1.0 % and 2.8%divergence in the 12S rRNA and 16S rRNA genes, respectively, from its nearest congener and is notably larger in cranio-dental measurements than other members of the genus occurring on Madagascar. This new species was previously iden-tified as N. melckorum, which is considered a junior synonym of southern African N. capensis. Neoromicia malagasyen-sis, an endemic to central western Madagascar, is the sister species to N. robertsi and the two are best considered vicariantspecies. Specimens provisionally assigned to N. malagasyensis, but notably smaller in baculum and skull size, and withdifferent baculum morphology, probably represent another unknown species from the island. Given the apparent rarity ofN. robertsi compared with other Malagasy members of this genus living in the eastern portion of Madagascar, it is considered a taxon of conservation concern.


Author(s):  
Yue Jiang ◽  
Lingmin Jiang ◽  
Yuxin Peng ◽  
Ki-Hyun Kim ◽  
Hyeon Ho Shin ◽  
...  

A Gram-stain-negative, aerobic, rod-shaped strain (R2A-3T) was isolated from the toxin-producing dinoflagellate Centrodinium punctatum and identified as a novel genus and new species based on a polyphasic taxonomic approach. The optimum conditions for growth of the strain were at 25 °C, pH 8.0 and in the presence of 3 % (w/v) NaCl. Phylogenetic analyses based on 16S rRNA genes and 92 core genes sets revealed that strain R2A-3T belongs to the family Nevskiaceae in the class Gammaproteobacteria and represented an independent taxon separated from other genera. The 16S rRNA gene of strain R2A-3T showed the highest sequence similarity to Polycyclovorans algicola TG408T (95.2%), Fontimonas thermophila HA-01T (94.1%) and Sinimarinibacterium flocculans NH6-24T (93.2%), and less than 92.8 % similarity to other genera in the family Nevskiaceae . The genome length of strain R2A-3T was 3608892 bp with 65.2 mol% G+C content. Summed feature 8 (comprising C18 : 1  ω7c and/or C18 : 1  ω6c) was the major fatty acid (>10 %). Diphosphatidylglycerol, phosphatidylglycerol and phosphatidylethanolamine were detected as the major polar lipids. The major respiratory quinone was ubiquinone-8. According to its phylogenetic, phenotypic, chemotaxonomic and genomic features, strain R2A-3T represents a new species in the new genus of the family Nevskiaceae . It is recommended to name it Flagellatimonas centrodinii gen. nov., sp. nov. The type strain is R2A-3T (=KCTC 82469T=GDMCC 1.2523T).


2015 ◽  
Vol 41 (1) ◽  
pp. 51-58
Author(s):  
Mohammad Shamimul Alam ◽  
Hawa Jahan ◽  
Rowshan Ara Begum ◽  
Reza M Shahjahan

Heteropneustesfossilis, Clariasbatrachus and C. gariepinus are three major catfishes ofecological and economic importance. Identification of these fish species becomes aproblem when the usual external morphological features of the fish are lost or removed,such as in canned fish. Also, newly hatched fish larva is often difficult to identify. PCRsequencingprovides accurate alternative means of identification of individuals at specieslevel. So, 16S rRNA genes of three locally collected catfishes were sequenced after PCRamplification and compared with the same gene sequences available from othergeographical regions. Multiple sequence alignment of the 16S rRNA gene fragments ofthe catfish species has revealed polymorphic sites which can be used to differentiate thesethree species from one another and will provide valuable insight in choosing appropriaterestriction enzymes for PCR-RFLP based identification in future. Asiat. Soc. Bangladesh, Sci. 41(1): 51-58, June 2015


Genes ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 40
Author(s):  
Liang Cui ◽  
Bitong Zhu ◽  
Xiaobo Zhang ◽  
Zhuhua Chan ◽  
Chungui Zhao ◽  
...  

The elevated NH3-N and NO2-N pollution problems in mariculture have raised concerns because they pose threats to animal health and coastal and offshore environments. Supplement of Marichromatium gracile YL28 (YL28) into polluted shrimp rearing water and sediment significantly decreased ammonia and nitrite concentrations, showing that YL28 functioned as a novel safe marine probiotic in the shrimp culture industry. The diversity of aquatic bacteria in the shrimp mariculture ecosystems was studied by sequencing the V4 region of 16S rRNA genes, with respect to additions of YL28 at the low and high concentrations. It was revealed by 16S rRNA sequencing analysis that Proteobacteria, Planctomycete and Bacteroidetes dominated the community (>80% of operational taxonomic units (OTUs)). Up to 41.6% of the predominant bacterial members were placed in the classes Gammaproteobacteria (14%), Deltaproteobacteria (14%), Planctomycetacia (8%) and Alphaproteobacteria (5.6%) while 40% of OTUs belonged to unclassified ones or others, indicating that the considerable bacterial populations were novel in our shrimp mariculture. Bacterial communities were similar between YL28 supplements and control groups (without addition of YL28) revealed by the β-diversity using PCoA, demonstrating that the additions of YL28 did not disturb the microbiota in shrimp mariculture ecosystems. Instead, the addition of YL28 increased the relative abundance of ammonia-oxidizing and denitrifying bacteria. The quantitative PCR analysis further showed that key genes including nifH and amoA involved in nitrification and nitrate or nitrite reduction significantly increased with YL28 supplementation (p < 0.05). The supplement of YL28 decreased the relative abundance of potential pathogen Vibrio. Together, our studies showed that supplement of YL28 improved the water quality by increasing the relative abundance of ammonia-oxidizing and denitrifying bacteria while the microbial community structure persisted in shrimp mariculture ecosystems.


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