Iwr

FIGURE 7.4. Embia major (Embioptera). (A) Male; and (B) female. [From A. D. Imms, 1913, On Embia major n. sp. From the Himalayas, Trans. Linn. Soc. Zool. 11:167-195. By permission of Blackwell Publishing Ltd.]

America and 65 from Australia, Ross (1970, 1991) suggested that this figure may represent only 10% of the world total.

As a group, the Embioptera are of remarkably uniform structure, a feature related to the widespread similarity of the tunnels in which they live. Webspinners are soft-bodied insects that fly only weakly or not at all. The prognathous head bears filiform antennae, compound eyes (often large and kidney-shaped in males, small in females), and mandibulate mouthparts. In males the mandibles are usually flattened and elongate. Ocelli are absent. No trace of wings can be seen in females; males may be apterous, brachypterous, or fully winged. In the latter the fore and hind wings are very similar. The radius is thickened; the other veins are reduced. The wings are flexible and able to fold at any point. This facilitates backward movement along the tunnels. For flight the wings are made more rigid by pumping blood into the radius. The forelegs are stout, and the basal tarsal segment is swollen to accommodate the silk glands, which number about 200. Ducts from the glands carry the product to the exterior via hairlike ejectors. The hind femur is also enlarged to contain a large tibial depressor muscle. This is correlated with the ability to run backward with great speed. There are 10 obvious abdominal segments. The cerci are two-segmented and tactile, serving as caudal "eyes" when the insect is running backward. In males the cerci are usually asymmetrical. .

The internal structure is generalized. The gut is straight, and 20-30 Malpighian tubules open into it. The ventral nerve cord is paired and includes three thoracic and seven abdominal ganglia. Each ovary consists of five panoistic ovarioles that are connected at intervals with the oviduct. A spermatheca is present. The five testis follicles on each side are also arranged serially along the vas deferens, which swells proximally into a seminal vesicle. Two pairs of accessory glands occur in males.

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.

Get My Free Ebook


Post a comment