Structure

Dermaptera are dorsoventrally flattened, pale brown to black insects that range in length from about 7-50 mm, and are readily recognized by the forceps at the tip of the abdomen. The prognathous head carries a pair of multisegmented antennae, a pair oflarge compound eyes (except in epizoic species where they are reduced or absent), and mandibulate mouthparts. Ocelli are absent. The pronotum is enlarged somewhat and has a quadrangular shape. The metanotum is also large and has two lines of spines that lock the tegmina in the resting position. Both the tegmina and hind wings are absent in epizoic forms and some free-living species. In other species the degree of wing development is varied. The tegmina are smooth, veinless structures that do not extend beyond the metathorax. The hind wings are membranous, semicircular structures composed mainly of a very large anal area supported by 10 radiating branches of the first anal vein. The preanal area is reduced to a small anterior area and contains only the radius and cubitus veins. The wings fold both longitudinally and transversely and are stored beneath the tegmina. The legs are more or less similar in form, increasing in size posteriorly. They bear a 3-segmented tarsus. The 10-segmented abdomen is flattened dorsoventrally and telescopic (because of the overlapping of the tergal plates). At its posterior tip is a smooth pygidium (called the eleventh segment by some authors). The form of the cerci is varied. In Forficulina they are unsegmented, forcepslike structures, more curved in the male than in the female. They are used offensively and defensively, and for assisting in the opening and closing of the wings, and during copulation. In epizoic species they are hairy, stylelike structures. In females of some primitive Forficulina a reduced ovipositor is found, but other Dermaptera lack this structure. Paired penes are found in males of some species, but usually one of these organs is reduced or absent.

The gut resembles that of other orthopteroids, except that it lacks mesenteric ceca. Between 8 and 20 Malpighian tubules occur, usually in groups of 4 or 5. The nervous system is generalized, the ventral nerve cord containing three thoracic and six abdominal ganglia. The tracheal system, which lacks air sacs, opens to the exterior via two thoracic and eight abdominal spiracles. In both sexes the reproductive system shows considerable variation. In males there is a pair of testes, paired vasa deferentia, single or paired seminal vesicles, and one or two ejaculatory ducts. In females, the ovaries are paired and contain polytrophic ovarioles. The ovarioles are arranged in two ways, either in three rows along the length of the lateral oviduct, or as a group at the anterior end of the oviduct.

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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