尖吻鲈仔鱼骨骼发育观察

掌握尖翅燕鱼 (Platax teira) 仔稚鱼脊柱及附肢骨骼系统的发育时序特征，可为其苗种繁育、环境适应及分类鉴定提供理论依据。采用软骨-硬骨双染色法对尖翅燕鱼仔稚鱼 [0~30日龄 (dah)] 脊柱、胸鳍、腹鳍、背鳍、臀鳍以及尾鳍进行染色观察与分析。结果表明，尖翅燕鱼有24枚脊椎骨，尾部骨骼由5枚尾下骨和2枚尾上骨构成，附肢支鳍骨的发育顺序为胸鳍、腹鳍、尾鳍、臀鳍和背鳍。尖翅燕鱼在初孵仔鱼已具备胸鳍支鳍骨原基和脊索，4 dah仔鱼胸鳍和腹鳍最先发育；7 dah仔鱼髓弓、脉弓开始出现；13 dah仔鱼骨骼形态和数量基本稳定；26 dah左右稚鱼开始骨化，脊柱和脊椎最先完成骨化；30 dah进入幼鱼阶段，其外表形态已经固定，与成鱼无异，典型特征为头部、躯干部和尾部各有3条黑色条带，身体呈雪白银色，受到外界刺激时体色瞬间变为黑色。尖翅燕鱼脊柱及附肢骨的发育顺序与其他海水鱼基本一致，但骨骼发育时间节点和数量有所不同。

A new alien fish in the Mediterranean Sea: Platax teira (Forsskal, 1775) (Osteichthyes: Ephippidae)

Understanding the developmental time sequence characteristics of the spine and appendage skeletal system of Platax teiracan provide a theoretical basis for its seedling breeding, environmental adaptation and classification. We stained and analyzed the spine, pectoral fin, pelvic fin, anal fin and caudal fin ofP. teira larvae (0–30 dah) by the method of cartilaginous and bony staining. The results show that there were 24 vertebrae, and the tail bone was composed of five subcaudal bones and two upper caudal bones. The development sequence of appendage branch fin bones was pectoral fin, abdominal fin, caudal fin, anal fin and dorsal fin. The first hatched fish already had pectoral branch fin bone primordium and notochord. At 4 dah, the pectoral fin and pelvic fin developed first; at 7 dah, medullary arch and vein arch appeared; at 13 dah, the morphology and number of larval bones were basically stable; at about 26 dah, ossification began in juvenile fish, and the spine and spine were the first to complete ossification; at 30 dah, the larvae entered the juvenile stage, and their appearance has been fixed. The typical characteristics were three black bands on the head, trunk and tail, and the body was white silver. When being stimulated or stressed by external stimulation, the body color changed to black instantly, and the shape had no difference from that of the juvenile. The developmental sequence of the spine and appendage bones was basically the same with that of other sea fish, but the time nodes and number of the development of bone were different.