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Of or relating to a system of sexual determination in which diploid females develop from fertilized eggs and haploid males develop from unfertilized eggs, as in most hymenopterans, such as ants and bees, and certain other invertebrates.
A haplodiploid organism or species.

[From Greek haploos, single; see haploid + diploos, double; see diploid + -oid.]

hap′lo·dip′loi′dy (-loi′dē) n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
References in periodicals archive ?
Hymenoptera have haplodiploid sex determination, meaning that unfertilized eggs become males (haploid) and fertilized eggs become females (diploid).
Some of the currently known host-reproductive manipulations include male killing, induction of parthenogenesis, feminization of genetic males, forced production of haploid individuals in haplodiploid systems, and cytoplasmic incompatibility (Werren 1997).
Wolbachia induced female parthenogenesis is less common and has only been documented in haplodiploid species such as thrips (Thysanoptera), mites (Acari) andwasps (Hymenoptera) [51].
impaternata and report evidence that impaternata arguably has eccentric reproductive biology due to the conjunction of gynogenesis and haplodiploid sex determination in its life cycle.
MATESOFT: a program for deducing parental genotypes and estimating mating system statistics in haplodiploid species.
Cytonuclear theory for haplodiploid species and x-linked genes.
If Blochmannia is similarly involved in manipulating ant reproduction and sex ratios toward females, it would in part share this "preference" with colony workers, who are also favored to manipulate sex ratios owing to relatedness asymmetries under haplodiploid genetics.
Eusociality is relatively rare in nature, and the traditional view has been that a haplodiploid reproductive pattern provides a genetic facilitator.
Male-killing bacteria have been observed in male heterogametic, female heterogametic, and haplodiploid hosts.