大别山区黑沟绿太阳鱼种群的形态特征研究

绿太阳鱼是2015年4月在大别山区淠河流域支流中新发现的入侵鱼类。利用2015年7月从黑沟中采集的78尾绿太阳鱼标本，对该物种的形态特征进行了详细测量和分析。结果发现绿太阳鱼种群内的形态相似性较高，但还存在一定的形态差异。相比性别，年龄是造成这种形态差异的主要原因。雄性从Ⅰ龄开始出现显著的形态分化，而雌性差异并不显著。这种形态学的差异完全符合雄鱼筑巢护卵的习性，具体表现在雄鱼头部指标（D1-2、D2-3、眼间距、眼后头长、头长）、臀鳍附近指标（D5-7、D5-8）、背鳍基部指标（D6-8）和尾柄处指标（D9-10）增大。同时相比Ⅰ龄以上的雄鱼，雌鱼和0龄雄鱼的尾柄指标（D8-10、D8-9）较长，身体更适于流水环境。这种雌雄体型上的变化，将有助于雄鱼占领溪流环境中的静水区（深潭），而雌鱼和0龄鱼占领流水区（急滩、湍流），这为该种群适应山区溪流的水文环境，合理分配生态位提供了便利条件，同时也使其对大别山区其他鱼类具有较大的生态危害潜力。

MORPHOLOGICAL CHARACTERISTICS OF THE GREEN SUNFISH (LEPOMIS CYANELLUS) IN HEIGOU CREEK,TA-PIEH MOUNTAINS

The green sunfish (Lepomis cyanellus), a new invasive fish in the Ta-pieh Mountain Area, was found in the tributary of Pihe River in April, 2015. A field investigation was conducted with 78 green sunfish caught from Heigou Creek in July 2015 to measure the fish’s morphological characteristics. The results revealed a high similarity between these fish but with certain morphological differences. Rather than gender, age might be the main reason for this diffe-rence. The most significant differentiation was in male but not female fish at the age of 1—2 years old, which might ex-plain by the breeding habits of males. Some morphological characteristics of males, such as the head indexes (D1-2, D2-3, interorbital width, postorbital head length, head length), the near anal fin indexes (D5-7, D5-8), the dorsal fin coxal (D6-8) and caudal peduncle width (D9-10), were larger than those of the females. Furthermore, the females and the fish at 0 years old were longer and higher caudal peduncle indexes (D8-10, D8-9) than those of the male fish at 1 years, which may adapt to live in moving water. Due to these morphological characteristics, the males are apt to live in the deep pools of streams, while the females and fish at 0 years old are likely to occupy the lotic habitats (run and riffle), which has brought great ecologically potential dangers to the fishery in Ta-pieh Mountains.