eChapter Name: Biology and Ecology of Schizothoracinae from Kashmir Waters
9789367554197
eBook Name: AQUATIC ECOSYSTEM IN COLD REGION
by Rinkesh Nemichand Wanjari, Zaheer Abass, Aadil Hussain Magloo, Tasaduq H. Shah, Farooz Ahmad Bhat
Introduction
Schizothoracinae, commonly known as snow trouts, are a specialized group of fish thriving in the fast-flowing, snow-fed streams and lakes of regions such as Afghanistan, Pakistan, the Himalayas in India and Nepal, China, and parts of the former USSR. Adapted to these challenging environments, Schizothoracinae have not been extensively studied due to the difficult terrain they inhabit. In India, they are primarily found along the Himalayan range, with an exception in the Periyar, Kerela (river and lake). The Indian Schizothoracinae are classified into seven genera, forming a significant part of Exclusively Distributed by NIPA GENX Electronic Resources and Solution Pvt. Ltd. New Delhi the Himalayan fishery. Resembling Salmonidae, they are commonly referred to as "Indian Trout." Early mentions of Schizothorax species by Day (1877, 1889) were brief. Subsequent taxonomic studies by researchers such as Hora (1921, 1934, 1937, 1953), Misra (1949), and Mukerji (1936) have provided a more comprehensive understanding of their taxonomy.
The Schizothoracinae, part of the Cyprinidae family, represent a diverse group uniquely adapted to high-altitude environments and have been categorized into three groups based on their morphological characteristics: "primitive group," "specialized group," and "highly specialized group" (Cao et al., 1981). The primitive group includes Schizothorax and Aspiorhynchus, which share more traits with the outgroup Barbodes hexagonolepis. They are distinguished by the presence of uroneuralia, three or four rows of pharyngeal teeth, minimal scale degeneration, and a lack of pronounced sexual dimorphism. The specialized group includes Ptychobarbus, Gymnodiptychus, and Diptychus, and is marked by the absence of uroneuralia, one or two rows of pharyngeal teeth, and moderate scale degeneration. The highly specialized group, which comprises Gymnocypris, Oxygymnocypris, Schizophygopsis, Chuanchia, and Platypharodon, is characterized by the complete absence of barbels and scales and a well-developed canalis preoperculomandibularis (Qi et al., 2012, Yonezawa et al., 2014). The genus Schizothorax comprises 63 species in total. Among these, 34 species are mainly found in Central Asia, while 28 species inhabit the Indo-Himalayan region. The species of Schizothorax in the Himalayan region include S. curvifrons, S. nasus, S. richardsonii, O. sinuatus, S. planifrons, S. esocinus, Schizothoraichthys progastus, S. longipinnis, S. kumanonensis, O. molesworthii, S. hugelli, S. labiatus, and S. micropogon (Menon, 1999; Mishra, 2003; Zhang et al., 2018; Ma et al., 2020).