Three locally isolated strains of entomopathogenic nematodes (EPNs), viz. Heterorhabditis indica, Steinernema thermophilum and Steinernema glaseri, from Meghalaya, India were characterized in terms of storage temperature and survival and infectivity of their infective juveniles (IJs). The survival and infectivity of nematode IJs was studied at, 5 ± 2 and 25 ± 2°C, for a period of 120 days, using deionized water as storage medium. The viability of nematode IJs was checked by mobility criterion at different storage periods, while the infectivity of nematode IJs was ascertained on the basis of establishment of IJs, using Galleria mellonella larva mortality tests in petridishes. The results of this study revealed that storage temperature markedly affects the survival as well as the establishment of nematode IJs of the three EPN species. At 5°C, comparatively higher rate of IJ's survival (i.e. 74-86 %) was observed for 15 days of storage, but the same reduced drastically to 28-32 % after 30 days of storage for H. indica and S. thermophilum. On the other hand, at 25°C, the survival of nematode IJs was observed till 120 days for all the three studied EPNs. In case of S. thermophilum and S. glaseri, higher rate of IJs survival ([75 %) was observed respectively at 15 and 30 days of observation. The study also showed that the establishment of IJs of the three EPN species declines with increase in storage periods, at both the test temperatures. In general, the nematodes stored at 25°C showed comparatively better establishment than those stored at 5°C. Among the three EPN studied, the establishment of S. glaseri was comparatively better than the rest of the species at both the temperatures and for different storage durations. In conclusion, our study adds further valuable information about the effect of storage temperature on survival and infectivity of three indigenous EPN species of Meghalaya, India which appears to be promising biocontrol agents of local insect pests.

Pseudolaguvia virgulata, a new South Asian sisorid catfish species, is described from the Barak River drainage in Mizoram, India. The new species can be distinguished from congeners in having a brown body with two or three narrow, pale longitudinal stripes and a pale Y-shaped marking on the dorsal surface of the head. Additional distinguishing characters from its congeners are a serrated anterior edge of the dorsal spine, the thoracic adhesive apparatus reaching beyond the base of the last pectoral-fin ray, head width, pectoral-fin length, length of dorsal-fin base, dorsal-spine length, body depth at anus, length of adipose-fin base, caudal peduncle length, caudal peduncle depth, snout length, interorbital distance, and total number of vertebrae.

Entomopathogenic nematodes (EPNs)

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 and 16S rRNA for) revealed that the entomopathogenic nematodes isolated from four different habitats and its symbiotic bacteria are conspecific with and respectively. The phylogenetic analysis based on maximum parsimony (MP) revealed that belongs to-- group. The study constitutes the first report of and its symbiotic bacteria outside the type locality, Vietnam, and in particular from India.

Chordodes mizoramensis, a new species of freshwater gordiid horsehair worm, is described from Mizoram, NE India on the basis of scanning electron microscopic and morphometric studies. The new species can be distinguished from its congeners in that the apical filaments of the crowned areoles are branched several times, a pattern that has not been observed in other species. An additional distinguishing character is that it has more bulging areoles, which are distributed among simple areoles alone or in groups, do not form clear patterns.