Table 1.
Body traits of male and female crayfish used in mating trials in the two years of study.
Figure 1.
Stained freshwater crayfish sperm cells released from spermatophores (40× magnification).
a) Phase contrast microscopy: note the radial nuclear arms or spikes spreading out from the sperm cells at activation; b) Fluorescence microscopy: the same sperm cells under fluorescence light with blue excitation filter (λ = 450–480 nm); living sperm with intact cellular membranes are green, while dead sperm are red.
Table 2.
Ejaculate traits of male crayfish used in this study.
Figure 2.
Relationships between sperm area and relative chelae size.
Relative chelae size is expressed as PC2 scores (see Methods). The regression line is shown.
Figure 3.
Relationships between sperm area and date of insemination.
The regression line is shown.
Figure 4.
Relationships between sperm longevity and male chelae asymmetry.
Both variables were √ arcsine-transformed and are thus expressed in degrees (°) (see Materials and Methods). The regression line is shown.