CHARACTERISTICS OF EARLY DEVELOPMENT OF SCHIZOTHORAX MACROPOGON IN XIZANG AUTONOMOUS REGION, CHINA

To protect Schizothorax macropogon, belong to Schizothorax, Schizothorax, this study investigated the embryonic and larval development characteristics of Schizothorax macropogon to provide technical support for its scientific protection and rational development. The results indicated that the egg with the diameter 3.0—3.2 mm were slightly sticky when met with water and then take off the stick. The egg hatched about 460.67 hours at temperature 10℃. Based on external morphological characteristics, embryonic development was separated into 7 stages, including cleavage preparing stage, cleavage stage, blastula stage, gastrula stage, neural embryo stage, organ differentiation stage, and hatching stage. Newly hatching fry with body length 9.9—11.0 mm, heart rate 48—50 beats/min, operculum, underjaw primordial radial of tail fin primordia clearly appeared. 2-day fry after hatching, nose concave appeared. Hepatopancreas primordial observed from 3 day fry after hatching, and gill raker and shoulder strap primordium shown in 4 day fry after hatching. The upper and lower jaw began to open and close in 6 day fry after hatching, and vascular differentiation ended, turned into mixed vegetative phase at 7 day fry after hatching. 14 day fry after hatching, swim bladder one room and pigment zone formed. 26 day fry after hatching, rib primordia developed. 35 day fry after hatching, swim bladder two room formed and yolk sac depleted. 63 day fry after hatching, dorsal fin differentiation ended and lateral line developed. 83 day fry after hatching, anal fin differentiation ended. An unique development timing for the first blastopore to metameres existed in Schizothorax macropogon, which is the adaptation and evolution to plateau environment.