Sperm Morphology and Comparison Morphometry Measurements of two Species
of Bats, Molossus molossus and Molossops temminckii (Chiroptera:
Molossidae)
Abstract
Sperm morphology is considered a species-specific character and has been
used as a tool in the classification of numerous mammalian taxa.
Neotropical bats have been poorly studied, and important aspects on
sperm morphology have not been elucidated. The aim of the present study
was to describe and compare the sperm morphology and morphometry of
Molossus molossus and Molossops temminckii. 14 adults
specimens were analyzed from the Colección Mamíferos Lillo, Universidad
Nacional de Tucumán: five Molossus molossus and nine
Molossops temminckii. The epididymis were extracted and macerated
in Farmer’s solution, followed by a coloration with different stains. To
carry out the description and morphometric analysis, microphotographs
were taken under an optical, epifluorescence and scanning electron
microscope. A total of 50 sperm from each individual were measured for
morphometric analysis. The length and width of the head, midpiece and
tail were taken as variables. Sperm from M. molossus and M.
temminckii were practically identical, both morphologically and
morphometrically. In both species, a distal bulge was observed at the
end of the intermediate piece in a percentage greater than 85%. The
main characteristics shared between the species were: presence of
acrosomal blebs in the upper half of the head of the spermatozoa;
cephalic equatorial segment with filiform ornamentations; intermembrane
space of head apex wedge-shaped; helical middle piece and annulus at the
end of middle piece. In the present study, scanning electron microscopy
allowed us to visualize structures, such as acrosomal vesicles, that
were not detected with other types of microscopy.