Structure

Adult. The hypognathous head usually is very mobile and bears very large, in some species holoptic, compound eyes. Three ocelli are usually present. The antennae contain between 9 and 70 segments and are sometimes sexually dimorphic. The mouthparts show a wide range in form from the generalized mandibulate type found in the suborder Symphyta to a highly specialized, sucking type found in the most advanced Apocrita, such as the bees (see Chapter 3, Section 3.2.2). The prothorax is small; its tergum is collarlike and fused with the large mesonotum. The pro-sternum is very small and usually can be seen only with difficulty. Two pairs of wings are generally present, with the fore wings larger than the hind pair. The venation is much reduced, and, rarely, veins are completely absent. The fore and hind wings are coupled by means of hamuli. Brachyptery or aptery occurs, for example, in ant workers and some Chalcidoidea. Hymenoptera are unique among Insecta in that a trochantellus is present on at least some legs. This is actually part of the femur, though it appears as a second segment of the trochanter. The legs are frequently specialized for particular functions, for example, digging, grasping, and carrying prey, and collection of pollen (see Chapter 3, Section 4.3.1 and Figure 3.25). In Symphyta the first abdominal segment is clearly recognizable as a part of the abdomen. In Apocrita, however, the tergum has become intimately fused with the metathorax and is distinguishable only by the presence of spiracles. In this condition it is known as the propodeum. The first abdominal sternite has disappeared entirely. In Apocrita, a marked constriction, the petiole, separates the first from the remaining abdominal segments; the latter constitute the gaster (metasoma) that normally has a posterior pair of unsegmented cerci (pygostyles), though these are reduced to pads of sensory hairs in some species and lost entirely in female Aculeata. The male terminalia are usually large and comprise the lateral parameres, the aedeagus, and a pair of ventral lobes, the volsellae. The ovipositor is well developed in females and is frequently modified for sawing, boring, piercing, or stinging, although only in the latter does it no longer participate in egg laying (Chapter 3, Section 5.2.1 and Figure 3.32).

The gut has a uniform structure throughout the order. The esophagus is narrow and long, especially when the petiole is elongate, and leads to a thin-walled crop (honey stomach) in the anterior part of the abdomen. Behind the crop is the proventriculus, which serves apparently to regulate the entry of food into the usually large stomach (ventriculus). This is followed by the ileum and rectum. The number of Malpighian tubules varies from 2, in most parasitic forms, to more than 250 in some nectar feeders. The nervous system shows various degrees of specialization; in primitive forms, three thoracic and nine abdominal ganglia occur in the ventral nerve cord, whereas in most Apocrita three thoracic and between two and six abdominal ganglia can be found. The paired testes are separate in Symphyta and a few Apocrita, but fused in other Hymenoptera. The vasa deferentia are swollen basally into vesicula seminales that lead into paired ejaculatory canals. The latter also receive the ducts of the two large accessory glands prior to forming a common tube. In females the number of polytrophic ovarioles varies from 1 to more than 100 per ovary. The two oviducts fuse to form the vagina, which also receives the duct of the median spermatheca. The vagina is swollen posteriorly to form the bursa copulatrix. Two major accessory glands occur, the venom (poison) glands and their associated sac, and the Dufour's gland. Originally,

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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