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Summary The present study provides length–weight relationship (LWR) of three fish species, Cynoglossus puncticeps (Richardson, 1846), Cynoglossus lingua Hamilton, 1822 and Cynoglossus lida (Bleeker, 1851) of family Cynoglossidae from Chilika lagoon (19°28′–19°54′N; 85°05′–85°38′E), India. A total of 147 specimens were sampled during March, July and October of 2017 from screen barrier nets (mesh 14 mm to 26 mm) locally called khonda jal operated by local fishermen. The estimated b values derived from the data sets as follows: 3.12 for C. puncticeps, 3.09 for C. lida, and 2.88 for C. lingua.

The paper reports occurrence of Lutke’s halfbeak Hemiramphus lutkei Valenciennes, 1847, for the first time from the coastal waters of Odisha coast, India. This report confirms the occurrence of this species form an extended geographical range along the east coast of India and will be helpful in further study of its biology, zoogeography and taxonomic status of the family Hemiramphidae.

The present study report the parasitic isopod infection on commercial fishes of the northern part of the east coast of India collected during the period 2010-2015 from the marine water of Odisha and West Bengal. During the study, 394 isopods were collected after examining 2668 fishes. These include 14 species of isopods, out of which 13 belong to 5 genera under the family Cymothoidae, and a single species Alitropus typus belongs to the family: Aegidae. Of theses, 03 species viz., Catoessa boscii, Cymothoa eremita and Nerocila loveni are first record to the northern part of east coast of India. Out of the 2668 fishes examined, 326 examples belonging to 34 species under 19 different families were infected by different isopods. Member of the host fish family Carangidae was more parasitized by isopods, followed by Clupeidae, Scoberidae, and Leiognathidae. The dominant isopods were Nerocila phaiopleura and Catoessa boschii. The total prevalence was 12.21. The prevalence was high on the host fish Alepes djedaba and lowest on Lutjanus johnii. The total infection caused by genus Alitropus was 1.52%, Anilocra was 5.07%, Catoessa was 24.87%, Cymothoa was 0.25%, Nerocila was 65.73%, and Norileca was 2.55%. The isopod prevention was high during the post-monsoon and low during the monsoon period.

Accurate identification and bio-ecology of mosquito vectors are of paramount importance in several respects including the development of species-specific vector control strategies. In the current study, we explored two different advanced tools such as Geometric morphometric (GM) and DNA barcoding analysis, to supplement morpho-taxonomy-based identification of malaria vectors. In landmark-based GM analysis, the pattern of wing shape was examined and we noticed a clear variation in their shape among different Anopheles species. Similarly, in the DNA barcoding studies, the phylogenetic analysis is based upon the marker genes such as mitochondrial Cytochrome oxidase subunit-I (mt COI), Cytochrome b (mt Cytb), and nuclear D3 domain of 28s rDNA gene sequences were carried out. The Neighbor-joining tree was formed by distinctive conspecific clusters illustrating genetic variation among different groups of Anopheles species. Further, genetic exchange among different Anopheline populations was analyzed by considering the COI gene sequences. In the gene flow study, the frequent genetic divergence, as well as gene exchange among Anopheles stephensi mosquito populations, was observed. Our findings suggested that GM analysis of the wing shape along with the DNA barcoding approach can effectively be used together for accurate identification of mosquito vectors including Anopheles stephensi and Anopheles barbirostris.