Structure

The minute to small (0.35-10 mm long) body is dorsoventrally flattened and shows a varied degree of sclerotization. In chewing lice the head is relatively large and bears chewing mouthparts that show certain resemblances to those of Psocoptera. In sucking lice the relatively small head has partially retracted, suctorial mouthparts. The labrum forms a short eversible proboscis. Three stylets are contained within a pouch that runs ventrally off the cibarium. The ventral stylet represents the modified labium, the middle stylet probably is an extension of the opening from the salivary duct, and the dorsal stylet is either the modified maxillae or the hypopharynx. The mandibles disappear during embryogenesis. The head bears three- to five-segmented antennae that may be filiform (in Anoplura), capitate and in grooves (Amblycera), or modified for grasping (Ischnocera). Compound eyes are reduced or absent and ocelli are never present. In Anoplura the thoracic segments are fused, but in other lice the prothorax is distinct from the pterothroax. The well-developed legs include a two-segmented or unsegmented tarsus and usually one or two tarsal claws. Eight to ten visible abdominal segments occur. Male genitalia include a permanently everted endophallus. There is no true ovipositor though in all sucking and some chewing lice the gonapophyses on segment 8 are used to attach eggs to the host's hair. Cerci are absent.

In sucking lice the cibarium and pharynx form a strong sucking pump, but the crop and gizzard are poorly differentiated. In chewing lice the crop is large. In all Phthiraptera the midgut is large and has two mesenteric ceca. Four Malpighian tubules enter the midgut posteriorly. The nervous system is highly modified and includes a composite metathora-coabdominal or thoracoabdominal ganglion. The internal reproductive organs generally resemble those of Psocoptera except that female Phthiraptera may have accessory glands and lack a spermatheca.

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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