Dih

FIGURE 3.8. Structure of (A) mandible, (B) maxilla, and (C) labium of a typical chewing insect. [From R. E. Snodgrass, Principles of Insect Morphology. Copyright 1935 by McGraw-Hill, Inc. Used with permission of McGraw-Hill Book Company.]

bears an inner lacinia and outer galea, and a maxillary palp. This basic structure is found in both apterygotes and the majority of chewing pterygotes, although in some forms reduction or loss of the lacinia, galea, or palp occurs. In Kukalova-Peck's (1991) view the cardo and stipes correspond to the subcoxa and coxa + trochanter, respectively, of the ancestral appendage; the lacinia and the galea to the coxal and trochanteral endites, respectively; and the palp to the remaining segments. The laciniae assist in holding and masticating the food, while the galeae and palps are equipped with a variety of mechano- and chemosensilla.

The labium (Figure 3.8C) is formed by the medial fusion of the primitive appendages of the postmaxillary segment, together with, in its basal region, a small part of the sternum of that segment. The labium is divided into two primary regions, a proximal postmentum corresponding to the maxillary cardines plus the sternal component, and a distal premen-tum homologous with the maxillary stipites. The postmentum is usually subdivided into submentum and mentum regions. The prementum bears a pair of inner glossae and a pair of outer paraglossae, homologous with the maxillary laciniae and galeae, respectively, and a pair of labial palps. When the glossae and paraglossae are fused they form a single structure termed the ligula.

Arising as a median, mainly membranous, lobe from the floor of the head capsule and projecting ventrally into the preoral cavity is the hypopharynx (Figures 3.3D and 3.9). It is frequently fused to the labium. In a few insects (bristletails and mayfly larvae) a pair of lobes, the superlinguae, which arise embryonically in the mandibular segment, become associated with the hypopharynx. The hypopharynx divides the preoral cavity into anterior and posterior spaces, the upper parts of which are the cibarium (leading to the mouth) and salivarium (into which the salivary duct opens), respectively.

Mouthpart Modifications. The typical chewing mouthparts described above can be found with minor modifications in Odonata, Plecoptera, the orthopteroids and blattoids,

FIGURE 3.9. Simplified sectional diagram through the insect head showing the general arrangement of the parts. [From R. E. Snodgrass, Principles of Insect Morphology. Copyright 1935 by McGraw-Hill, Inc. Used with permission of McGraw-Hill Book Company.]

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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