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Serologic and molecular tests were performed for the diagnosis and to detect O. tsutsugamushi genotypes that are circulating in the state of Mizoram, India. Blood samples from scrub typhus-suspected patients were collected from Synod Hospital, Durtlang, Mizoram. Weil-Felix and immunochromatographic test (ICT) were performed from the serum samples. Nested PCR (nPCR) amplification of 47kDa outer membrane protein antigen gene and 56kDa type-specific antigen gene were done from the whole blood. 141/177 (79.66%) and 134/177 (75.7%) cases showed the presence of antibody against scrub typhus by Weil-Felix and ICT assays respectively. 76/177 (42.93%) patients showed the presence of 47kDa OMP antigen gene by nPCR while 55/177 (31.07%) showed the presence of 56kDa TSA gene by nPCR. Phylogenetic analysis of 56kDa TSA gene sequence revealed that Karp-related genotype was the most common genotype in the study area followed by Kato-related genotype. In this study, a high degree of diversity of O. tsutsugamushi was observed similar to the observations reported from other parts of India. Nested PCR of 47kDa OMP antigen gene showed higher sensitivity as compared to nPCR amplification of 56kDa TSA gene suggesting it as the assay of choice for diagnosis of scrub typhus disease.

Background Outbreak of the fall armyworm Spodoptera frugiperda (J.E. Smith, 1797) (Lepidoptera: Noctuidae) occurred in Mizoram, North-Eastern India. The infestation spread in the entire state covering a total area of around 2840 hectares of maize cultivated land. Entomopathogenic nematodes (EPNs) represent potential candidates for the biological control of S. frugiperda. In the study, the susceptibility of the pest against 4 locally isolated EPN species Heterorhabditis indica, H. baujardi, Steinernema sangi and S. surkhetense was evaluated. Results The results indicated that all the isolated EPN species showed a high rate of larvicidal and pupicidal activities against the pest. Mortality between 43.75–100.00 and 25.00–100.00% of 3rd and 5th larval instars, respectively (at concentrations 10–800 IJs/larva), and 37.50–68.75% mortality of pupae (at concentrations 200–1600 IJs /pupa) were found after exposure to the EPN species. The mortality rate of the pest showed significant variations with life stages of the host insect, nematode concentrations and incubation time. Based on the median lethal concentration (LC50), H. indica was the most pathogenic species, followed by S. sangi, H. baujardi and S. surkhetense. The LC50 values of H. indica at 72 h post-incubation were 20.26 and 62.07 IJs/larva for the 3rd and 5th larval instars, respectively, and 913.34 IJs/pupa. The penetration assay showed that H. indica had the highest penetration rate into the hosts, 27.24, 21.30 and 20.00% in the 3rd, 5th larval instars and pupae, respectively. Furthermore, all the EPN isolates were capable of successful multiplication inside the cadaver of S. frugiperda that showed significant differences with the EPN isolates and life stages of the pest. Among the isolates, H. indica showed the highest multiplication rates, 17,692.25 ± 2103.59, 8345.63 ± 785.34 and 79,146.38 ± 5943.73 IJs per 3rd instar larva, 5th instar larva and pupa, respectively. Conclusions The study revealed that the 4 species of EPNs showed a high potency against S. frugiperda, thereby having the potential to be developed as a biological control agent against the pest. Moreover, the isolated EPN species could potentially serve as alternatives for chemical insecticides and could further be incorporated into the Integrated Pest Management (IPM).

We present a first record for three species of frogs, viz. Amolops indoburmanensis, Euphlictys kalisgraminensis and Polypedates braueri in India based on DNA barcoding data. We also discussed on the records of Amolops spp. in Mizoram and delisted all previous recorded species, viz. A. afghanus, A. kaulbacki and A. marmoratus from the amphibian fauna of Mizoram until further research confirmed their presence, since the data were not sufficient enough for the confirmation of their occurrence and are likely based on misidentification of A. indoburmanensis.

Most studies on the diversity of amphibians in northeast India were based on classical morpho-taxonomy, which have a high probability of errors in species identification. DNA barcoding of amphibians using the mitochondrial 16S rRNA gene has been used successfully for the identification of species and detection of cryptic species. In the present study, we carry out DNA barcoding of two rhacophorid species of the genus Raorchestes and Kurixalus that are not readily identifiable to the species level based on their morphology. Our analysis on the 16S rRNA gene revealed that these species were Raorchestes cangyuanensis and Kurixalus yangi, species which were recorded for the first time and second time from India respectively. We discuss on the records of R. longchuanensis from Bangladesh and India, which were based on the misidentification of R. cangyuanensis. We therefore propose to delist this species from the faunal list of Bangladesh and India. We further raise a question as to why the population of Kurixalus from Motuo, Xizang province of China was assigned as K. naso and not the population described as K. yangi, which is morphologically similar to K. naso and is also recorded from a locality close to the type locality of K. naso.

Stoliczka (1870) described Hylorana nicobariensis from the Nicobar Islands of India. The generic allocation of this enigmatic species is yet to be fully resolved (Chan et al. 2020b) and it has been placed in different genera (Boulenger 1885; Frost et al. 2006; Che et al. 2007; Oliver et al. 2015; Chan et al. 2020a; Chandramouli et al. 2020). As of now, the species is assigned to the genus Indosylvirana (Oliver et al. 2015; Chan et al. 2020b; Frost 2020). Apart from Nicobar archipelago, this species is distributed in the insular regions of southeast Asia (Oliver et al. 2015; Chandramouli et al. 2020; Frost 2020) and the states of Arunachal Pradesh, Assam, Mizoram, Tripura and West Bengal in northeast India (Sarkar et al. 1992, 2002; Sarkar & Ray 2006; Ahmed et al. 2009; Mathew & Sen 2010; Lalremsanga 2011; Lalremsanga et al. 2015, 2016). However, Frost (2020) doubted the records of this species in northeast India. Systematic studies on the herpetofauna of northeast India based on molecular evidence are scanty (Lalronunga et al. 2020a), and species recorded from the area need confirmation (Frost 2020). Recent studies revealed that many species previously recorded from northeast India were based on misidentifications (Das et al. 2019; Giri et al. 2019; Lalronunga et al. 2020b), therefore, a review and revalidation on the herpetofaunal list of the area is warranted. Herein, we examined the identity of the species recorded as I. nicobariensis from northeast India using morphological data and a fragment of 16S rRNA mitochondrial gene.

We provide the first molecular phylogenetic data for the following poorly known Northeast Indian snakes: Blythia reticulata and B. hmuifang, Hebius xenura, and Trachischium spp. Based on 1071 bp of cytb, 578 bp of nd4, 509 bp of 16s, 1000 bp of rag1 and 672 bp of cmos, we found support for a monophyletic Blythia being a member of Natricinae, most closely related to Trachischium. Hebius xenura is recovered as nested within species of the recently resurrected genus Herpetoreas, to which we transfer it.

Isolation of entomopathogenic nematodes from Mizoram, northeastern part of India includes a Heterorhabditis species never been recorded in India. The morphological and multigene (ITS rRNA, 28S rRNA and COI) sequences analysis had revealed that the isolated Heterorhabditis belongs to Heterorhabditis baujardi, originally described from Vietnam. The phylogenetic tree (both MP and ML) revealed that the H. baujardi belongs to H. indica clade, and further, forms a monophyletic clade (99/98% and 94/92% bootstrap support for ITS and 28S respectively) with H. amazonensis, H. floridensis, H. mexicana and H. taysearae forming H. baujardi sub clade. The multigene characterization revealed that both the ITS and 28S rRNA showed similar result in resolving the phylogenetic relationship of the genus Heterorhabditis, with the ITS rRNA being superior based on the strong bootstrap support, whereas, the cytochrome c oxidase I (M1–M6 partition) can be a good supportive tool for species delimitation. This is the first report of H. baujardi from India envisaging its future use as a biological control agent, and further incorporated into the IPM.

A survey was conducted to isolate indigenous EPN, specifically from the northeastern part of India, a biodiversity hotspot region, to record the occurrence and their further use as biological control agent. The morphological and molecular analysis (ITS rDNA for Steinernema and 16S rRNA for Xenorhabdus) revealed that the entomopathogenic nematodes isolated from four different habitats and its symbiotic bacteria are conspecific with Steinernema sangi and Xenorhabdus vietnamensis respectively. The phylogenetic analysis based on maximum parsimony (MP) revealed that Steinernema sangi belongs to feltiae-kraussei-oregonense group. The study constitutes the first report of Steinernema sangi and its symbiotic bacteria Xenorhabdus vietnamensis outside the type locality, Vietnam, and in particular from India.

Physoschistura chhimtuipuiensis , new species, from a tributary of the Kaladan River in Mizoram, northeastern India, is distinguished from all other species of Physoschistura by a combination of the following characters: scales between pectoral- and pelvic-fin bases deeply embedded and sparsely set, lateral line incomplete with 56–63 pores, reaching slightly beyond the base of the last anal-fin ray, a suborbital flap in male, 8½ branched dorsal-fin rays and 8+7 branched caudal-fin rays.

The complete mitochondrial genome of Himalayan bee Apis laboriosa, from Mizoram, India, has been sequenced using Illumina NextSeq500 platform and analysed. The mitogenome was assembled and found to be 15 266 bp in length and the gene arrangement is similar to other honey bee species. The A. laboriosa mitogenome comprises of 13 protein-coding genes (PCGs), 22 tRNAs, 2 rRNAs and an A + T-rich region of 346 bp. Based on the concatenated PCGs, in the phylogenetic tree, A. laboriosa is placed as a sister group along with the cavity nesting honey bees. The present study reports the first complete mitochondrial genome sequence of A. laboriosa, which will enhance our knowledge on Apinae mitogenomes and phylogeny.