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第二性征是动物在性成熟所表现的、可以用来分辨物种性别的特征。第二性征比较容易在现生物种中观察到,但是它们很难在化石中识别。近期,研究者根据采集于云南罗平中三叠世安尼期海相地层的三十块鱼化石,发现了基干新鳍鱼的一个新属种:多饰维纳斯鱼(Venusichthys comptus)。维纳斯鱼具有明显的性双型:成年雄鱼具有第二性征,包括雄鱼头部、鳞片和鳍条上的尖突,以及臀鳍前面钩状的接触器。这些第二性征可能用于增进雌、雄鱼体产卵前或产卵中的身体接触,刺激雌鱼排卵,以及保护巢穴和领地。维纳斯鱼不具有肋鳞鱼
The second character is the animal’s sexual maturity, which can be used to distinguish the gender characteristics of the species. Secondary characters are easier to observe in living species, but they are difficult to identify in fossils. Recently, the researchers discovered a new genus of Basmatians newfin fish, Venusichthys comptus, based on thirty fish fossils collected in the Middle Triassic Annyian marine strata in Luoping, Yunnan. Venus has obvious sexual double forms: adult males have secondary sexual characteristics, including croaks on male heads, scales and rays, and hook-shaped contactors in front of anal fins. These secondary signs may be used to enhance female or male body contact before they spawn or spawn, stimulate female ovulation, and protect lair and territory. Venus fish does not have rib fish