Ann. Entomol. Soc. Am. 76: 400-402 (1983) ABSTRACT No males were found among 559 specimens of Pityophthorus puberulus (LeConte) from several localities. No sperm was found in the spermatheca of 10 females taken from recently established galleries containing eggs and young larvae. This is the third record of thelytoky in a scolytid. The known distribution and environment of parthenogenetic popul...

Parthenogenesis is a form of asexual reproduction found in females, where growth and development of embryos occurs without fertilization by a male. Parthenogenesis occurs naturally in aphids, Daphnia, rotifers, nematodes and some other invertebrates but can also be induced efficiently in mammalian oocytes by providing appropriate stimuli in-vitro. Recently, parthenogenesis has attracted wide at...

The centrosome, the microtubule-organizing center of the cell, is introduced typically by the sperm at fertilization. In some mammals, however, this paternal pattern of inheritance appears to be violated. The hypothesis that the centrosome is maternally inherited was tested during parthenogenesis, polyspermy, and polygyny as well as after recovery from microtubule inhibition at first mitosis. D...