Aguiar Odair, Garda Adrian A, Lima Albertina P, Colli Guarino R, Báo Sônia N, Recco-Pimentel Shirlei M
Departamento de Biologia Celular, Instituto de Biologia, Universidade Estadual de Campinas, (UNICAMP), 13084-971, Campinas, SP, Brasil.
J Morphol. 2003 Jan;255(1):114-21. doi: 10.1002/jmor.10052.
This study describes the spermatozoa of the dendrobatids Epipedobates femoralis and Colostethus sp. using light and transmission electron microscopy. Both species possess a biflagellate spermatozoon, an unusual characteristic only previously reported in two anuran species belonging to the families Leptodactylidae and Racophoridae. The acrosomal complex of both species consists of a conical acrosomal vesicle and a subacrosomal cone, both of which cover the anterior portion of the nucleus, but to differing extents. In the midpiece, the centrioles are disposed parallel to each other and to the cell axis and give rise to two axonemes. Two paraxonemal rods were also seen entering the nuclear fossa. Both flagella are surrounded by a single mitochondrial collar. Each flagellum is formed by an axial fiber connected to the axoneme by an axial sheath; juxta-axonemal fibers are absent. Our data seem to support that Epipedobates femoralis should be placed in a separate clade possibly related to Colosthetus and that these two genera may not be monophyletic.
本研究利用光学显微镜和透射电子显微镜描述了箭毒蛙科的股斑箭毒蛙（Epipedobates femoralis）和姬蛙科（Colostethus sp.）的精子。这两个物种都拥有双鞭毛精子，这是一种不寻常的特征，此前仅在细趾蟾科和树蛙科的两种无尾目物种中报道过。这两个物种的顶体复合体均由一个圆锥形顶体囊泡和一个顶体下锥组成，二者均覆盖细胞核的前部，但覆盖程度不同。在中段，中心粒彼此平行且与细胞轴平行排列，并产生两条轴丝。还可见两根副轴丝进入核窝。两根鞭毛均被单个线粒体环包围。每条鞭毛由一条通过轴鞘与轴丝相连的轴向纤维形成；不存在近轴丝纤维。我们的数据似乎支持股斑箭毒蛙应置于一个可能与姬蛙属相关的单独分支中，并且这两个属可能不是单系的。
