H. Choudhury

Schistura larketensis , a new cavernicolous fish (Teleostei: Nemacheilidae) from Meghalaya, Northeast India

Schistura larketensis, a new species of cavernicolous loach, is described from Khung, a limestone cave in Meghalaya, India. The species differs from Schistura papulifera, its only troglomorphic congener from northeast India, in having a smooth ventral surface of the head, the presence of a small cylindrical axillary pelvic lobe, and the presence of three pores in the supratemporal canal of the cephalic lateral-line system. Apart from these differences, the species can be immediately distinguished from all other species of Schistura from the Brahmaputra River and neighboring basins by the complete absence (or only vestigial presence) of eyes.

Figure 6 In Schistura Larketensis, A New Cavernicolous Fish (Teleostei: Nemacheilidae) From Meghalaya, Northeast India

FIGURE 6. Lateral view of head showing gradual reduction and loss of eyes (black arrows) with increasing size in Schistura larketensis; a, paratype GUMF 0262/2, 45.1 mm SL; b, holotype, GUMF 0261, 54.5 mm SL; c, paratype GUMF 0263/2, 63.1 mm SL; d, paratype, GUMF 0263/2, 68.1 mm SL.Scale bar 1 mm; e,graphical representation of decreasing eye diameter (ED) with respect to increase in standard length (SL).

Impact of Open Cast Coal Mining on Fish and Fisheries of Simsang River,Meghalaya, India

Present paper deals with the impact of coal mining activities on the water quality and fish diversity of Simsang River from 2009 to 2015. Six sampling sites were selected on the basis of affected and unaffected areas of coal mining activities. Certain water quality attributes such as water colour, temperature, pH, dissolved oxygen, free CO2, chloride, total alkalinity, total dissolved solids, nitrate, ammonia, phosphate and sulphate were analysed along with the assessment of relative abundance of fishes. The estimated value of studied water quality parameters such as pH, dissolved oxygen and total alkalinity indicates degradation of water quality due to the effect of acid mine drainage (AMD) of coal mining. Polycyclic aromatic hydrocarbon (PAH) showed highest concentration of 4-ring PAH and Benzo[a]anthracene was the most important pollutant in the water collected from affected sites. Relative abundance of fish diversity was also estimated less in affected area of the River. A total of 64 fish species under 20 families were collected with highest number in cyprinidae family. The calculated value of diversity indices reflected the declining trend of fish diversity in the coal mining affected areas of the river due to degradation of water quality.