Structure

Thrips are generally yellowish, brown, or black elongate insects that range in length from about 0.5 to 15 mm. The hypognathous or opisthognathous head is devoid of sutures and sulci and bears a pair of prominent compound eyes, four- to nine-segmented antennae inserted close together on the head, and asymmetrical suctorial mouthparts. The labrum, labium, and maxillary stipites form a short cone-shaped rostrum that encloses the styletlike left mandible and paired laciniae. The right mandible disappears during embryogenesis. Labial and maxillary palps are present. Ocelli (three) are found only on winged adults. The prothorax is large and free, the mesothorax and metathorax fused. The forelegs are usually slender but may have enlarged tarsal teeth and swollen femora for gripping. The tarsi are unsegmented or two-segmented and at their tip carry a bladderlike structure (arolium) that can be everted by means of hemolymph pressure to enable the insect to walk on a variety of surfaces. Wings may be fully developed, shortened, or absent. When present they are membranous, narrow structures with few or no veins. Each possesses a fringe of long setae. The fore and hind wings are coupled during flight. The 11-segmented abdomen tapers posteriorly. Females of the suborder Tubulifera have a delicate, reversible, chutelike ovipositor, but in Terebrantia this is usually a strong, external structure with four sawlike valves. Both tubuliferan and terebrantian males have well-developed external genitalia.

The internal structure of Thysanoptera is generally similar to that of Hemiptera. There is a large cibarial pump anterior to the alimentary canal. The foregut is short and leads into a large midgut, which is differentiated into an anterior croplike region and tubular hind portion. There are four Malpighian tubules. The nervous system is highly specialized. The subesophageal and prothoracic ganglia are fused, those of the mesothorax and metathorax remain separate, and those of the abdomen have coalesced to form a single center. Each ovary contains four "neopanoistic" ovarioles (secondarily derived from the ancestral polytrophic condition). A spermatheca occurs, but accessory glands may or may not be present. In males the testes are fusiform and connect via short vasa deferentia to the ejaculatory duct. The latter also receives ducts from one or two pairs of large accessory glands.

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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