Mumbai: Withstanding all the global volatility due to Brexit (Britian's exit from the European Union), key Indian equity indices on Monday morning opened marginally in red. The 30-scrip Sensitive Index (Sensex), was trading 53.11 points or 0.20 per cent lower during the morning session. The wider 51-scrip Nifty of the National Stock Exchange (NSE) was also trading 17.50 points or 0.22 percent lower at 8,071.10 points. The Sensex of the BSE, which opened at 26,347.81 points, was trading at 26,344.60 points (at 9.17 a.m.) in the early session, lower 53.11 points or 0.20 per cent from the previous day's close at 26,397.71 points. The Sensex touched a high of 26,371.67 points and a low of 26,298.87 points in the trade so far.