Molecular identification of a new myxozoan, Myxobolus dermiscalis n. sp. (Myxosporea) infecting scales of Labeo rohita Hamilton in Harike Wetland, Punjab (India)

Abstract

In the present study, a new species Myxobolus dermiscalis n. sp. infecting scales of Labeo rohita, an Indian major carp from Harike Wetland in Punjab, India has been described on the basis of spore morphology and amplification of a part of 18S rDNA gene. The pseudocysts of M. dermiscalis n. sp. are milky white with irregular outline, 0.5–3.6 mm in diameter embedded within the dermal scale in the form of a cavity. The spores 5.84–7.98 × 3.98–5.98 μm in size, having two equal polar capsules 3.98–5.98 × 1.85–3.85 μm in size. The most differentiating feature from closely related species, Myxobolus saugati (Kaur and Singh, 2011) is the presence of two parietal folds at the posterior – lateral margins of the shell valves. The present species is regarded as host, organ and tissue specific in nature. The partial sequence of SSU gene of M. dermiscalis n. sp. clustered with other Myxobolus species infecting cyprinids available in the GenBank. Blast search revealed 98% homogeneity with Myxobolus sp (KM401439) infecting scales of L. rohita in Myanmar (unpubl. data). The present myxobolid parasite has been recorded to cause serious, highly symptomatic disease of the scales, causing their loosening from the skin of L. rohita. It rendered the host fish unsightly giving it cloudy appearance with white patches and mucoid body surface. Scale pseudocyst Index (SPI) has been provided to record the intensity of infection.

The occurrence of known Myxobolus and Thelohanellus species (Myxozoa, Myxosporea) from Indian major carps with the description of Myxobolus bandyopadhyayi n. sp. in West Bengal

“…Some of them were placed next to already sequenced species like Myxobolus dermiscalis or Thelohanellus caudatus . In the case of Myxobolus dermiscalis , the morphology and sequence data from previous studies ( Kaur et al, 2016 ) were consistent with our results, and its identification raised no doubts at all. However, Thelohanellus caudatus samples are grouped into two distinct clades.…”

“…Remarks: The collected spores were in ethanol-fixed preserved state and showed only the most important figures for identification. The horizontal flattened plate at the anterior end of the spores resembled closely to the figures presented by Kaur et al (2016) . However, the authors made some mistakes in measuring oocysts.…”

“…The spores of this species had equal polar capsules. It was identified as Myxobolus dermiscalis Kaur et al (2016) based on its morphological and molecular characteristics. In the plasmodia from catla and mrigal, Myxobolus spp.…”

Histopathological tissue alterations of targeted organs of ornamental goldfish, Carassius auratus in India caused by a new pathogenic bacterial strain, Bacillus licheniformis PKBMS 16 identified on the basis of morpho- biochemical and 16S rDNA characterization

“…The rates of different nucleotide substitution from one base and to another base were assessed. The rates of transition were more than transversion for all base substitutions and stable AIC has been found from the data which indicated the strong ancestral phylogeny of the present species divergence from the earlier described species (Kaur et. al.…”

What Determines the Minimum Body Size for Vertebrates?

“…Comparably simpler animals can reach even smaller sizes, the highly reduced parasitic cnidarian Myxobolus shekel reaches an adult size of only 89 m and was initially even mistaken for a protist (Kaur et al, 2016;Fig. 2).…”