Structure

Taken as a group, the Orthoptera, in keeping with their varied biology, exhibit a wide range of anatomical and morphological features. Though they are mostly medium-sized to large insects, the order includes some of the largest and the smallest members of the class. The head is usually hypognathous, but may be prognathous in some burrowing species, katydids, and tree crickets. The compound eyes are typically large, and the antennae vary from comparatively short (suborder Caelifera) to very long (suborder Ensifera). Eyes and antennae are reduced in size in burrowing or cave-dwelling forms. The mouthparts are mandibulate but show some modifications according to the diet of the insect and occasionally to other considerations. The pronotum is large and extends lateroventrally to cover the pleural region. The mesothoracic and metathoracic nota are closely associated, though the basic components can still be readily distinguished (see Chapter 3, Section 4.2). The legs are unequally developed. The forelegs of primarily digging forms are short but much enlarged. In some predaceous species the fore femora and/or tibiae are equipped with rows of long spines. In almost all Ensifera the fore tibiae bear auditory organs (see Chapter 12, Section 3.2). The hind femora of most species are greatly enlarged to accommodate the muscles used in jumping, but they may also be modified for production of sound by having a row of small pegs on their inner face. Typically, the two pairs of wings are well developed, but varying degrees of reduction of the fore and hind wings, or the latter alone, may occur, especially in females. In several groups, the wings may be modified to resemble leaves, grass blades, or stems so as to camouflage the insect. Whether fully developed or not, the fore wings are thickened and known as tegmina. The hind wings, unless reduced, are broad, because of the development of a large anal area. The wing venation, particularly of the tegmina, is varied and frequently modified in conjunction with stridulation. Paired auditory (tympanal) organs (see Chapter 12, Section 3.2), if present, occur in both sexes and are found either on the first abdominal segment (in Acridoidea) or on the fore tibiae (in Tettigonioidea and Grylloidea). Eleven abdominal segments are distinguishable, though the sternum of the first is closely associated with the metathorax, and the most posterior segments are modified in conjunction with reproduction. In females a well-developed ovipositor is usually found, except in primarily burrowing forms. It is made up of three pairs of valves, though the inner pair may be reduced (see Chapter 3, Section 5.2.1). In Ensifera the ovipositor is long and used to place eggs in crevices, soft ground, or plant tissues. In Caelifera the ovipositor valves are short and stout in accordance with the digging function that they perform. In most Orthoptera the "external" copulatory structures of males are enclosed within a pouch formed by the greatly enlarged ninth abdominal sternum. The cerci are unsegmented and, in most species, short and rigid. However, in many Ensifera (especially Grylloidea) they are rather long and flexible, and in males of many species (especially Tettigonioidea) they are modified to form clasping structures used during copulation.

The internal structure of Orthoptera is usually rather generalized. In the gut the crop is large and proventriculus fairly to very well developed. The anterior midgut possesses mesenteric ceca, two in Ensifera, usually six in Caelifera. There are many Malpighian tubules that enter the gut directly or via a common duct. In the central nervous system there are three thoracic and three to seven abdominal ganglia. The tracheal system, which

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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