Structure

chapter 9 Adult. A characteristic feature of most Mecoptera is the ventral prolongation of the head into a broad rostrum. Incorporated into this structure are the clypeus, labrum, and maxillae. Compound eyes are well developed, and in most species there are three ocelli. The antennae are multisegmented and filiform. The mouthparts are mandibulate, except in Nannochorista, where they are specialized and may be interpreted as foreshadowing the suctorial type seen in lower Diptera. The prothorax is small, the pterothorax well developed. The legs are long and thin and adapted for walking. They have a five-segmented tarsus. In Bittacidae the fifth tarsal segment folds back on the fourth and is used for catching prey. Two pairs of fully developed, identical, membranous wings are present in most species; the venation is primitive. In Boreidae the wings of females are small sclerotized pads while those of males are hooklike and used to grasp the female during mating. Wings are reduced in some female Panorpodidae and Bittacidae, and absent in female Apteropanorpidae. The abdomen of females is 11-segmented and usually carries 2-segmented cerci (unsegmented in Bittacidae and Boreidae). In female Boreidae the 10th tergum is prolonged and together with the pointed, sclerotized cerci forms a functional ovipositor. In males segment 9 is bifurcate and bears a pair of bulbous claspers. Segment 10 is inconspicuous and bears unsegmented cerci. The aedeagus lies at the base of the claspers. In Panorpidae the terminal segments are turned upward and resemble somewhat a scorpion's sting, hence the common name for the order.

The foregut has two interesting features. The esophagus contains two dilations that appear to form a sucking apparatus, and the crop is provided with long setae (acanthae) that may act as a filter. Six Malpighian tubules occur. The nervous system is generalized, with three thoracic and between five and eight abdominal ganglia (males usually with one more than females). Each testis comprises three or four follicles. The paired vasa defer-entia open separately into a median seminal vesicle, which also receives paired accessory glands. In females each ovary contains 7-19 polytrophic ovarioles (panoistic ovarioles in Nannochoristidae and Boreidae). The paired oviducts unite before entering a genital pouch. The ducts from the spermatheca and accessory glands also lead into the pouch.

Larva andPupa. Larvae are typically caterpillarlike, with a distinct head capsule that bears simple eyes. Prolegs occur on the first eight abdominal segments, and the apex of the abdomen bears either a suction disc or a pair ofhooks. In Boreidae and Panorpodidae larvae are grublike, lacking prolegs and a terminal suction disc. Larvae of Nannochoristidae are very elongate, lack prolegs, but have a pair of apical hooks. Pupae are decticous and exarate.

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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