摘要：We examined the testicular histology and spermatozoal dimensions of the bird-voiced treefrog, Hyla avivoca (Anura: Hylidae), from samples collected in May, June, and July from localities in three counties (Calhoun, Conway, and Little River) in Arkansas. Calling frogs were necropsied in the lab, and testes were prepared for light and scanning electron microscopy. Spermatocysts within seminiferous tubules of all males contained large aggregates of spermatozoa. Primary spermatogonia, the largest of all germ cells, ranged from 13.3 – 17.8 μm in diameter (= 15.37 ± 1.22; n = 20). Measurements of sperm dimensions yielded the following length parameters (range, mean ± standard deviation, sample size): acrosome, 2.10 – 3.37 μm (= 2.58 ± 0.40; n = 11); nucleus, 10.22 – 13.71 μm (= 11.70 ± 0.86; n = 65); acrosome, nucleus, midpiece complex (ANM) in three frogs, 14.87 – 23.98 μm (= 19.62 ± 2.72; n = 17), 18.83 – 26.96 μm (= 22.92 ± 2.26; n = 17), 17.40 –26.96 μm (= 23.92 ± 3.27; n = 11); principal piece, 24.36 – 27.68 μm (= 25.98 ± 1.19; n = 14); total tail length (endpiece intact), 29.87 – 39.00 μm (= 33.37 ± 2.63; n = 23); and total sperm length, 51.02 – 62.98 μm (= 54.63 ± 3.54; n = 20). Our sperm morphometric findings complement previously published data on this species and fill in gaps that may aid in future intra- and interfamilial comparisons.
