Adult. The great majority of adult Lepidoptera (i.e., the Ditrysia, which includes about 98% of the described species) have a very constant fundamental structure, a feature that has led to some difficulty in establishing the phylogeny and classification of the order. Lepidoptera range in size from very small (wingspans of about 3 mm) to very large (wingspans of 25 cm). The entire body and appendages are covered with scales (modified hairs). The compound eyes are large and cover a major portion of the head capsule. Two ocelli are present in most species but are concealed by scales. The antennae are of varied size and structure. In most Lepidoptera mandibles are absent and the maxillae are modified as a suctorial proboscis (see Chapter 3, Section 3.2.2 and Figure 3.12). When not in use the proboscis is coiled beneath the thorax. In most species the prothorax is reduced and collarlike. The mesothorax is the larger of the pterothoracic segments, which bear large tegulae, a characteristic feature of the order. Auditory organs are present on the metathorax of Noctuoidea. Both the fore and hind wings are generally large, membranous, and covered with scales. The latter are flattened macrotrichia supported on a short, thin stalk; they may be solid (the "primitive-type" scales found in non-Glossata) or with an internal cavity that may contain pigments ("normal-type" scales of Glossata). The iridescent colors of many Lepidoptera result from the layered structure of the scale (see Chapter 11, Section 4.3). In males of some species certain scales (androconia) are modified so as to facilitate the volatilization of material produced in the underlying scent glands. In primitive Lepidoptera the wing venation is identical in the fore and hind wings (homoneurous) and resembles that of primitive Trichoptera. In advanced forms there is considerable divergence between the venations of the fore and hind wings (the heteroneurous condition). The wing-coupling apparatus of primitive Lepidoptera comprises simply the small jugum of the fore wing, which lies on top of the hind wing. Occasionally a few frenular bristles are present on the anterior part of the hind wing, which assist in coupling. In higher Lepidoptera the coupling apparatus is usually made up of the retinaculum of the fore wing and frenulum of the hind wing (Chapter 3, Section 4.3.2 and Figure 3.28). However, in certain families the frenulum has been lost, and wing coupling is achieved simply by overlapping. The humeral area of the hind wing is greatly enlarged and strengthened, and lies beneath the fore wing. This is the amplexiform system. In females of a few species wings are reduced or lost. There are 10 easily identifiable abdominal segments, though the sternum of segment 1 is missing and the 9th and 10th (sometimes also the 7th and 8th) segments are modified in relation to the genitalia. The male genitalia are complex and their homologies unclear. In females there are three basic types of genitalia: monotrysian, exoporian, and ditrysian. In the monotrysian type there is a single genital opening on fused sterna 9 and 10 that serves both for insemination and for oviposition. In the exoporian type, found in Hepialoidea and Mnesarchaeoidea, there are separate openings for insemination and oviposition though both occur on fused segment 9/10, and in Ditrysia the opening for insemination is on sternum 7 or 8, with that for egg laying on fused segment 9/10 (Figure 19.3). In most species the genital aperture is flanked by a pair of soft lobes, but these may be strongly sclerotized and function as an ovipositor in species that lay their eggs in crevices or plant tissue. A pair of auditory organs is found on segment 1 in some moths. Cerci are absent.

The anterior region of the foregut is modified as a pharyngeal sucking pump from which a narrow esophagus leads posteriorly and, in some forms, expands to form a crop. In higher Lepidoptera, however, the crop is a large lateral diverticulum. The midgut is short and straight, the hindgut longer and coiled. In most species there are six Malpighian

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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