Independent Researcher, Fushun, Liaoning Province, 113006, China. E-mail:
Zool Stud. 2024 Sep 4;63:e24. doi: 10.6620/ZS.2024.63-24. eCollection 2024.
The occurrence of cyclic morphological alternation in male crayfish of the family Cambaridae following molting is widely acknowledged. However, there remains a contentious issue within the genus : Some previous studies have proposed that male exhibit a pair of noncorneous Form II gonopods during the non-breeding season, while others argue that these species lack Form II in adult males. This study examined the color and shape of the corneous tips on the gonopod to determine its form. Additionally, morphometric methods were utilized to distinguish between Form II adults and juveniles. The results of the study confirm the presence of Form II adults in and . The Form I gonopod is characterized by four golden-colored corneous terminal elements, whereas the Form II gonopod features blunt, non-corneous terminal elements, on which the color is the same as that of the surrounding surface. Furthermore, cyclic dimorphism on the gonopod of was observed seasonally, and distinct morphological differences in the chela were noted between Form I and Form II adults.
溪蟹科雄性小龙虾蜕皮后出现周期性形态交替的现象已得到广泛认可。然而，该属内仍存在一个有争议的问题：一些先前的研究提出，雄性在非繁殖季节会展现出一对非角质化的II型交接器，而另一些研究则认为这些物种的成年雄性缺乏II型交接器。本研究检查了交接器角质化尖端的颜色和形状以确定其类型。此外，还利用形态测量方法来区分II型成年个体和幼体。研究结果证实了[具体物种1]和[具体物种2]中存在II型成年个体。I型交接器的特征是有四个金色角质化末端元素，而II型交接器的末端元素钝圆、非角质化，其颜色与周围表面相同。此外，还季节性地观察到[具体物种3]交接器的周期性二态性，并且注意到I型和II型成年个体在螯上存在明显的形态差异。
