ABSTRACT
ABSTRACT The genus Neogriphoneura Malloch, 1924 is currently composed of 11 species with New World distribution. Neogriphoneura timida Curran, 1942 is recorded for the first time in South America, with occurrences in Brazil, Colombia and Trinidad and Tobago; and new Central American records are presented: Belize, Honduras and Mexico. Here we redescribe the species and present, for the first time, illustrations of the male terminalia and female spermathecae, and discuss the main diagnostic characteristics of external morphology. A brief discussion about the postcopulatory sexual selection in this species is proposed based on morphology of the spermathecae.
ABSTRACT
After natural or artificial insemination, the spermatozoon starts a journey from the site of deposition to the place of fertilization. However, only a small subset of the spermatozoa deposited achieves their goal: to reach and fertilize the egg. Factors involved in controlling sperm transport and fertilization include the female reproductive tract environment, cell-cell interactions, gene expression, and phenotypic sperm traits. Some of the significant determinants of fertilization are known (i.e., motility or DNA status), but many sperm traits are still indecipherable. One example is the influence of sperm dimensions and shape upon transport within the female genital tract towards the oocyte. Biophysical associations between sperm size and motility may influence the progression of spermatozoa through the female reproductive tract, but uncertainties remain concerning how sperm morphology influences the fertilization process, and whether only the sperm dimensions per se are involved. Moreover, such explanations do not allow the possibility that the female tract is capable of distinguishing fertile spermatozoa on the basis of their morphology, as seems to be the case with biochemical, molecular, and genetic properties. This review focuses on the influence of sperm size and shape in evolution and their putative role in sperm transport and selection within the uterus and the ability to fertilize the oocyte.