Ovipositor


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ovipositor

[′ō·və‚päz·əd·ər]
(invertebrate zoology)
A specialized structure in many insects for depositing eggs.
(vertebrate zoology)
A tubular extension of the genital orifice in most fishes.

Ovipositor

 

the external sexual organ in the females of many insects and some fish (for example, Rhodeus) by means of which eggs are laid. The ovipositors of insects are modified appendages to the eighth and ninth abdominal segments. They consist of three pairs of valves with the sexual orifice located between their bases. The valves of the ovipositor penetrate the substrate, and the eggs slide down between the valves during egg laying.

Because the eggs of Acrididae are placed into the soil in sacs that must be deposited at great depths, the ovipositor is strong and short and acts as a digging apparatus. The abdomen of the Acrididae can become elongated in order to push down the ovipositor. In dragonflies, true bugs, cicadas, and sawflies, the ovipositor places the eggs into plant tissue. Ichneumon flies and other hymenopterans have a long and sharp ovipositor that introduces eggs into the bodies of other insects, where the larvae live as parasites. The ovipositors of higher hymenopterans (honeybees, wasps, bumblebees) have become stingers—organs of protection and attack.

In fish the ovipositor is a modified urogenital papilla, which becomes elongated during spawning.

A. V. IVANOV

References in periodicals archive ?
Male sixth through eighth abdominal segments completely retractable within the anterior part of the abdomen, gonocoxite and gonostylus of male terminalia extremely prolonged and thin; ovipositor elongated and protractible, cercus with simple setae.
Stephomyia is a monophyletic genus, supported by eight synapomorphies, five homoplastic: ovipositor shorter than abdomen (19), none lateral facial papillae (27), abdominal dorsal spines absent (30), gall longer than large (37); and three non-homoplastic: male circumfila sinuous (8), gonostylus short and triangular (10), female cerci: completely fused (23).
2010; Proud & Felgenhauer 2011, 2013), ozopores (Gnaspini & Rodrigues 2011), penises (Kury & Villarreal 2015; Kury 2016), and ovipositors (Martens et al.
Hembras, el ovipositor es mas largo (5.8 mm vs 5.2 mm) y mas ancho (2.3 mm vs 1.9 mm), el plato subgenital distalmente emarginado en "v" vs., redondo en M.
Ovipositor short, wide, strongly curved with rough lateral surface (Fig.
To see them one had to lower one's gaze, which with Ovipositor had been projected toward an imaginary exterior--though their subject directed our imagination toward the sky.
A longer ovipositor allows eggs to be deposited deeper within the gill cavities of mussels, reducing competition for space and oxygen between deposited eggs (Kitamura 2006a).
Ovipositor short, less than 1.5 times as long as pronotum, laterally compressed, bent sharply upward in basal part; upper margin beyond base almost straight.
The most powerful method is the direct observation of abdominal tip movements of the ovipositing female, which can reflect fertilization action during the course of egg transfer from the common oviduct to the ovipositor [15, 16].