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Start Over Subject 591.4

2. Insemination and fertilization in the seed bug Lygaeus simulans (Heteroptera: Lygaeidae)

Creator:
Micholitsch, Thomas, Krügel, Peter, and Pass, Günther
Format:
print, text, and regular print
Type:
article, model:article, and TEXT
Subject:
Lygaeidae, kopulace, entomologie, hmyz, ploštice, Lygaeus simulans, kopulační orgány, morfologie, inseminace, fertilizace, Heteroptera, genitalia, copulation, cryptic female choice, sperm utilization, spermatheca, aedeagus, processus gonophori, insemination, fertilization, 595.2/.7, and 591.4
Language:
English
Description:
In the laboratory, not all females of the seed bug Lygaeus simulans Deckert, 1985, produced fertilized eggs after copulation: 26.7% of the females were not inseminated and 5% were inseminated but did not lay fertilized eggs; only in 40% of the couples did copulation result in fertile eggs. The remaining 28.3% of couples refrained from mating. Duration of copulation was associated with insemination and fertilization: (i) fertile eggs were produced by only one couple that copulated for less than 60 min and all those that copulated for more than 360 min, (ii) probability of fertilization increased steadily with duration of copulation between 60 and 360 min, and (iii) duration of copulation was significantly different for couples that showed different insemination status. A possible morphological explanation for this rime dependency was revealed by examining the genitalia of 69 couples freeze-fixed in copula after different periods in copulation. Because of the intricate structure of the genitalia in L. simulans, a male takes a long time to manoeuver its intromittent organ into the narrow insemination duct of the female. Only if completely inserted is the tip of the intromittent organ close enough for successful ejaculation of sperm into the spermatheca. The freeze-fixing experiment revealed that it usually took the male more than 30 min to locate the entrance to the insemination duct and another 30 min for full penetration. This explains why copulations that lasted less than 60 min failed, since insemination began only after intromission was complete. The experiments, therefore, indicated that there is a relationship between the complex morphology of the genitalia and the low rates of insemination and fertilization in L. simulans., Thomas Micholitsch, Peter Krügel, Günther Pass, 7 obrázků, 1 tab., and Lit.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

3. Morfologie a fysiologie zvířat hospodářských: učebná kniha pro střední školy hospodářské

Creator:
Hessler, František
Publisher:
Unie
Format:
print, text, regular print, and 140 s. ; v. 8°
Type:
model:monograph and TEXT
Subject:
636.1/.5, 591.4, 591.1, 636, 24, 37.016, 22, hospodářská zvířata, morfologie zvířat, fyziologie zvířat, Chov zvířat. Živočišná výroba, and Učební osnovy. Vyučovací předměty. Učebnice
Language:
Czech
Description:
František Hessler, Se 127 obr. část. bar. v textu, and Converted from MODS to DC version 1.8 (EE patch 2018/05/24)
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public