Search results
Results from the WOW.Com Content Network
The number of segments in an antenna varies amongst insects, with higher flies having 3-6 segments, [21] while adult cockroaches can have over 140. [22] The general shape of the antennae is also quite variable, but the first segment (the one attached to the head) is always called the scape, and the second segment is called the pedicel.
The thoracic segments have one ganglion on each side, which are connected into a pair, one pair per segment. This arrangement is also seen in the abdomen but only in the first eight segments. Many species of insects have reduced numbers of ganglia due to fusion or reduction. [8]
The metathorax is the segment that bears the hindwings in most winged insects, though sometimes these may be reduced or modified, as in the flies , in which they are reduced to form halteres, or flightless, as in beetles , in which they may be completely absent even though forewings are still present. All adult insects possess legs on the ...
This glossary of entomology describes terms used in the formal study of insect species by entomologists.. When present, elytra of the Staphylinidae are markedly abbreviate. This fly in the genus Scaptomyza has clearly visible rows of para-sagittal acrostichal bristles on its thorax the alitrunk of aculeate Hymenoptera comprises the three thoracic segments, plus the propodeum, which strictly ...
It is also called mesosoma or cephalothorax in other arthropods. It is formed by the prothorax , mesothorax and metathorax and comprises the scutellum ; the cervix , a membrane that separates the head from the thorax; and the pleuron , a lateral sclerite of the thorax.
Insects have spiracles on their exoskeletons to allow air to enter the trachea. [1] [page needed] In insects, the tracheal tubes primarily deliver oxygen directly into the insects' tissues. The spiracles can be opened and closed in an efficient manner to reduce water loss. This is done by contracting closer muscles surrounding the spiracle.
Two thoracic segments are fused into the head; one thoracic segment is in the posterior tagma. Other kinds of copepod also have two tagmata but formed by different segments. The development of distinct tagmata is believed to be a feature of the evolution of segmented animals, especially arthropods. In the ancestral arthropod, the body was made ...
[11] [13] Palpi consist of a short basal segment, a comparatively long central segment, and a narrow terminal portion. The first two segments are densely scaled and may be hirsute; the terminal segment is bare. The terminal segment may be blunt or pointed; it may project straight or at an angle from the second segment inside which it may be ...