spermatheca


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Related to spermatheca: Aedeagus

spermatheca

(spûr′mə-thē′kə)
n. pl. spermathe·cae (-sē)
A receptacle in the reproductive tract of many female or hermaphrodite invertebrates and certain female vertebrates, in which spermatozoa are received and stored until needed to fertilize the ova.

sper′ma·the′cal adj.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

spermatheca

a sac for the storage of sperm, a ‘seminal receptacle’ as occurs in the female reproductive tract of many lower animals, such as insects and PLATYHELMINTHS.
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
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Families with single spermatheca include Apachyidae, Labiduridae, Anisolabididae, Chelisochidae, Spongiphoridae, and Forficulidae.
Considering the importance of the spermatheca in the reproductive biology of insects, studies that provide morphological and physiological data regarding this organ are important for future research into population management of insects that are disease vectors.
Update Procedure for Male's Sperm Reservoir and Female's Spermatheca. At the beginning, the number of sperms in each male's sperm reservoir and the size of each female's spermatheca are randomly initialized within the range [0,1].
a) External ventral view of anterior region (scale 4 mm); b) Dorsal view of right spermatheca from segment 9 (scale 1 mm); c) Distal part of penial seta from segment 17 (scale 100 [micro]m).
Morphology of spermatheca in the estuarine crab Chasmagnathus granulata Dana 1851 (Grapsidae, Sesarminae).
The copulatory duct falls into the globular spermatheca. The walls of the spermatheca are porous.
Initialize workers Randomly generate the queens Apply local search to get a good queen For a pre-defined maximum number of mating-flights For each queen in the queen list Initialize energy (E), speed (S), and position The queen moves between states And probabilistically chooses drones prob/(Q, D) = [e.sup.-(difference/speed)] If a drone is selected, then Add its sperm to the queen's spermatheca S(t+1) = [alpha] x S(t) E(t + 1) = E (t) - [gamma] End if Update the queen's internal energy and speed End for each Generate broods by crossover and mutation Use workers to improve the broods Update workers' fitness While the best brood is better than the worst queen Replace the least-fittest queen with the best brood Remove the best brood from the brood list End while End for 3.
Therefore, in Danaus butterflies, ideal lock and key mechanism may not be present but other factors like selective spermatheca usage by females and postzygotic barrier play key role in restraining gene flow between two species.
When a Portunus trituberculatus male mates with a molted female and sperm transfer occurs, the seminal fluid of the male can form a hard sperm plug within the female spermatheca (Xuan et al.
Female: Cibarium with four radiated triangular horizontal teeth, an irregular row of small vertical teeth, and complete arch; spermathecal individual ducts shorter than 4 times the length of the furca stem; spermatheca broader than long, spherical, without annulations, narrowest than spermathecal common duct (Ibanez-Bernal 2003).
A large, granulate accessory gland leads into the seminal duct between its membranous and sclerotized parts (visible only in right spermatheca. A similar structure has previously only been observed once in salticids, in Ballus chalybeius (Walckenaer, 1802)--see Wesolowska and Tomasiewicz 2008).
The uterus externus is separate from the internal structures by projections that form a valve that makes the connections between internal structures, the spermatheca and the exterior via the genital opening (unpublished data).