Figure 2.

Scanning electron microscopy of the foam nest frog (Rhacophorus sp.). (A) Bundle of sperm associated with one Sertoli cell in testis. Note the head with about 11 tight coils. (B) Higher magnification of one sperm showing detail of acrosome and the 11 head coils. (C) Extended head coils once sperm are exposed to external medium and (presumably) foam produced by female. (D) Star symbol plot analysis on the basis of seven kinematic parameters comparing sperm motility of six frog (Anura) species from South Africa. Abbreviations for kinematic parameters: DNC, DANCE; LIN, Linearity; mnALH, Mean Amplitude of Head Displacement; PM, Progressive motility; VAP, Average path velocity; VCL, Curvilinear velocity; VSL, Straight line velocity.