Table 2.

Partitioning of the variance in sperm morphometric and dynamic traits into: variance between species, among males of a single species, and within males

	Source of variance
	Between species	Among males	Within male	Total	Repeatability T. merianae	Measurement error T. merianae	Repeatability T. rufescens	Measurement error T. rufescens
Head length
Variance estimate ± SD	0.048 ± 0.221	0.735 ± 0.857	1.092 ± 1.045	1.875	0.97	0.06	0.97	0.05
Midpiece length
Variance estimate ± SD	0.0269 ± 0.164	0.100 ± 0.316	0.297 ± 0.545	0.424	0.84	0.05	0.75	0.04
Flagellum length
Variance estimate ± SD	2.582 ± 1.607	1.235 ± 1.111	12.163 ± 3.487	15.98	0.96	0.2	0.98	0.13
Total length
Variance estimate ± SD	4.123 ± 2.030	1.755 ± 1.325	13.782 ± 3.712	19.66	0.97	0.23	0.99	0.14
VCL
Variance estimate ± SD	4.309 ± 2.076	46.442 ± 6.815	53.01 ± 7.281	103.761	0.97	1.6	0.96	1.64
VSL
Variance estimate ± SD	2.726 ± 1.651	34.473 ± 5.871	74.078 ± 8.607	111.269	0.99	0.61	0.99	0.68
LIN
Variance estimate ± SD	0 ± 0	0.0014 ± 0.038	0.021 ± 0.1436	0.0224	0.97	0.00082	0.92	0.0011

The variance due to measurement errors was obtained using 15 males of each species; five spermatozoa of each male were measured four times. All morphometric and dynamic traits showed high and significant measurement repeatability (Sperm morphometric traits: T. merianae all F_{74, 300} > 24.47, P < 0.0001; T. rufescens all F_{74, 300} > 13.32, P < 0.0001; sperm dynamic traits: T. merianae all F_{74, 300} > 119, P < 0.0001; T. rufescens all F_{74, 300} > 46.14, P < 0.0001).