noun
definition
The lower jaw, especially the lower jawbone.
definition
One of a pair of mouthparts of an arthropod, designed for holding and cutting food.
Examples of mandibles in a Sentence
In most insects that feed by suction the mandibles are modified.
Biting mandibles; second maxillae completely fused.
The abdomen is oval, sandy-grey in hue and beset with warts and bristles; the prothorax forms a mobile neck for the large square head, which carries a pair of long and powerful toothed mandibles.
There are about 600 species in the family, the males being usually larger than the females, and remarkable for the size of their mandibles.
The mandibles are strong, adapted for biting the vegetable substances on which these beetles feed, and the palps of the second maxillae have three segments.
The insects of this order have mandibles adapted for biting, and two pairs of membranous wings are usually present; the first abdominal segment (propodeum) becomes closely associated with the fore-body (thorax), of which it appears to form a part.
The mandibles, which are frequently used for carrying various objects, are situated well to the outside of the maxillae, so that they can be opened and shut without interfering with the latter.
These cocoons, which may often be seen carried between the mandibles of the workers, are the "ants' eggs" prized as food for fish and pheasants.
Sharp to hold the maggots between their mandibles and induce them to spin together the leaves of trees from which they form their shelters, as the adult ants have no silk-producing organs.
Accessory organs are rarely found on the genital ducts, but occur in Paludina, Cyclostoma, Naticidae, Calyptraeidae, &c. Mandibles usually present.
No mandibles, and radula uniserial.
The head of an insect carries usually four pairs of conspicuous appendages - feelers, mandibles and two pairs of maxillae, so that the presence of four primitive somites is immediately evident.
The mandibles often furnish a good example of "secondary sexual characters," being more strongly developed in the male than in the female of the same species.
As previously mentioned, a pair of minute jaws - the maxillulae- are present in the lowest order of insects, between the mandibles and the first maxillae.
In front or above the mouth is bounded by the labrum, while the mandibles and first maxillae lie on either side of it.
Biting mandibles; minute but distinct - maxillulae; second maxillae incompletely fused.
Biting mandibles; vestigial maxillulae; second maxillae incompletely fused.
Biting mandibles; second maxillae incompletely fused.
Biting mandibles; second maxillae incompletely fused; maxilIulae often distinct.
Biting mandibles.
Piercing mandibles, retracted within the head-capsule.
Mandibles and first maxillae modified as piercers; second maxillae fused to form a jointed, grooved rostrum.
Mandibles absent in imago, very exceptionally present in pupa; first maxillae nearly always without laciniae and often without palps, or only with vestigial palps, their galeae elongated and grooved inwardly so as to form a sucking trunk.
Mandibles rarely present, adapted for piercing; first maxillae with palps; second maxillae forming with hypopharynx a suctorial proboscis.
Biting mandibles; second maxillae incompletely or completely fused; often forming a suctorial proboscis.
All these orders agree in the possession of biting mandibles, while their second maxillae have the inner and outer lobes usually distinct.
The Hemiptera, with their piercing mandibles and first maxillae and with their second maxillae fused to form a jointed beak, stand far apart from them.
Specialized as they are in form, development and habit, they retain mandibles for biting, and in their lower sub-order - the Symphyta - the maxillae are hardly more modified than those of the.Orthoptera.
All spiders possess a pair of poison-glands, one in each of the chelicerae or mandibles and opening by means of a duct at the tip of the fang.
The mouth parts are well developed, consisting of an upper lip, powerful mandibles, maxillae with three-jointed palpi, and a deeply quadrifid labium or lower lip with three-jointed labial palpi.
A minute entosternite having the above-described structure is found in the Crustacean Apus between the bases of the mandibles, and also in the Decapoda in a similar position, but in no Crustacean does it attain to any size or importance.
They differ from the Crustacea in that they have only a single pair of prae-oral appendages, the second pair being definitely developed as mandibles.
The segmentation of the prosoma and the form of the appendages bear a homoplastic similarity to the head, pro-, meso-, and meta-thorax of a Hexapod with mandibles, maxillary palps and three pairs of walking legs; while the opistho io i e d c b o a S' S" 2 I VT V S IV III II I Opisthosoma Prosoma FIG.
Tracheae, except in the aquatic species in which they are atrophied, opening by a pair of stigmata situated close to or above the base of the appendages of the 1st pair (mandibles).
The proboscis of tsetse-flies is without the paired piercing stilets (mandibles and maxillae) possessed by other bloodsucking Diptera, such as the female horse-flies and mosquitoes.
Snakes possess teeth in the maxillaries, mandibles, palatine and pterygoid bones, sometimes also in the intermaxillary; they may be absent in one or the ether of the bones mentioned.
Sharp, recurved teeth are carried by the mandibles, the pterygoids, palatines, maxillaries, and in the Pythoninae by the premaxillaries also.
The prefrontal bones are still in contact with the nasals as in the previous families, but the coronoid bones of the mandibles are absent as in the remaining families, and this loss also occurs in the Boine Charina.
Apart from this feature the Trichoptera also differ from the typical Neuroptera in the relatively simple, mostly longitudinal neuration of the wings, the absence or obsolescence of the mandibles and the semi-haustellate nature of the rest of the mouth-parts.
Through this temporary protection the active pupa, which closely resembles the mature insect, subsequently bites a way by means of its strong mandibles, and rising to the surface of the water casts the pupal integument and becomes sexually adult.
Fabre states that the lastnamed insect uses a stone for the temporary closing of her burrow, and the Peckhams have seen a female Ammophila take a stone between her mandibles and use it as a hammer for pounding down the earth over her finished nest.
The mandibles are without palp. The pairs of feet are four to six.
The mandibles are normally five-jointed, with remnants of an outer branch on the second joint, the biting edge varying from strong development to evanescence, the terminal joints or " palp " giving the organ a leg-like appearance and function, which disappears in suctorial genera such as Paracytherois.
Giesbrecht and Hansen have shown that the mouth-organs consist of mandibles, first and second maxillae and maxillipeds; and Claus himself relinquished his long-maintained hypothesis that the last two pairs were the separated exopods and endopods of a single pair of appendages.
Thorell's classification (1859) of Gnathostonta, Poecilostoma, Siphonostoma, based on the mouth-organs, was long followed, though almost at the outset shown by Claus to depend on the erroneous supposition that the Poecilostoma were devoid of mandibles.
The tenth abdominal segment carries a pair of jointed cerci which are often elongate, and the feelers are always long, while the jaws are usually feeble and membranous, though the typical parts of a mandibulate mouth are present - mandibles, maxillae with inner and outer lobes and palps, and second maxillae (labium) whose lacinae are not fused to form a ligula.
In the absence of cerci the Corrodentia are more specialized than the Isoptera and Plecoptera, but some of them show a more primitive character in the retention of vestigial maxillulae - the minute pair of jaws that are found behind the mandibles in the Aptera.
The larvae are active and well-armoured, upon the whole of the ' ` campodeiform " type, but destitute of cerci; they are predaceous in habit, usually with slender, sickle-shaped mandibles, wherewith they pierce various insects so as to suck their juices.
Some American genera (Corydalis) which belong to this family are gigantic among insects and their males possess enormous mandibles.
They are abundantly distinct from the Neuroptera and Mecaptera, through the absence of mandibles in the imago, the maxillae - both pairs of which possess the typical inner and outer lobes and jointed palps - forming a suctorial apparatus.