Beetles mating

Reproduction

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1. Introduction
   1. Mitosis
   2. Meiosis
2. Reproduction in Insects
   1. Sexual
      1. Oviparity - eggs produced, fertilized and deposited in environment (most insects).
      2. Ovoviviparity - eggs produced and fertilized but retained and hatched in female's body. Immatures are ready to feed upon deposition (flies).
      3. Viviparity - egg fertilized but development of immature occurs in body of female. Some or all nourishment from mother (tsetse flies; parthenogenetic generation of aphids - see "C. Asexual").
   2. Sexual - Asexual; Haplodiploidy (ants, bees; wasp parasitoids)
      1. Haploid - unfertilized eggs become males.
      2. Diploid - fertilized eggs become females.
   3. Asexual (parthenogenesis) (common in wasps, beetles, aphids)
      1. Oviparity - eggs produced and deposited in environment (weevils, wasp parasitoids).
      2. Viviparity - eggs hatch in female. Some nourishment from mother (parthenogenetic generation of aphids).
   4. Alternation of sexual and asexual generations (some aphids)
   5. Paedogenesis - reproduction by immature insect - rare
   6. Hermaphrodite
3. Internal Reproductive System
   1. Female
      1. Paired ovaries (usually with several ovarioles)
      2. Lateral oviduct
      3. Common oviduct
      4. Genital chamber (bursa copulatrix)
      5. Vulva
      6. Accessory gland (various secretions for egg attachment or protection)
      7. Spermatheca (spermatozoa or spermatophore storage) and spermathecal gland
   2. Male
      1. Paired testes
      2. Vas deferens
      3. Seminal vesicle
      4. Accessory glands (semen or spermatophore secretions)
      5. Ejaculatory duct
      6. Intromittent organ (penis, aedeagus)
4. External Reproductive Structures
   1. Female
      1. Ovipositor
      2. Sensilla (sense cells - chemoreceptors, mechanoreceptors)
   2. Male (aedeagus, claspers)
5. Mating
   1. Copulation
   2. Transfer of spermatozoa or spermatophores
6. Oviposition
   1. Maturation of eggs within ovariole
      1. Germarium (mitosis)
      2. Vitellarium (meiosis)
      3. Vitellogenesis (deposition of yolk) and vitellogenins
   2. Fertilization (micropyle)
   3. Oviposition
7. Derivation of scientific terms and prefixes

   Aedeagus - (Gr. aidoia, genitals; agein to lead) In males, the intromittent organ.

   Bursa - (L. bursa, purse) Any pouch or sac, a sac-like cavity; bursa copulatrix (L. copulare, to couple) is a genital pouch of insects.

   Diploid - (Gr. diploos, twofold) Having two sets of chromosomes (2n).

   Haploid - (Gr. haplos, single) Having one set of chromosomes (1n).

   Hermaphrodite - (GR. hermaphroditos, combining both sexes) An individual bearing recognizable male and female tissues and producing male and female gametes at some period of the life cycle.

   Oviparity - (L. ovum, egg; parere, to bring forth) Egg-laying.

   Ovoviviparity (L. ovum, egg; vivus, alive) Producing eggs that are incubated and hatched within the female’s body with the larvae being "born" instead of an egg deposited.

   Paedogenesis - (Gr. pais, child; genesis, origin) Parthenogenetic reproduction by larvae structurally unable to copulate.

   Parthenogenesis - (Gr. partheos, virgin; genesis, origin) The development of an individual from an unfertilized egg.

   Spermatheca - (Gr. sperma, seed; theke, case) A small sac associated with the median oviduct of the female in which sperm are stored after copulation; seminal receptacle.

   Spermatophore - (Gr. pherein, to bear) A packet or capsule produced by the accessory glands of male insects and transferred to the female reproductive tract containing sperm and often other proteinaceous materials.

   Viviparity - Female insects that give "birth" to larvae; implies that nourishment is given to offspring before birth.

Suggested Readings: Gullen, P. J. and Cranston. P. S. (1994).
pp. 90-93, All of section 3.8; pp. 139-148, Section 5.8 to 5.11.

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