Adult. Adult Megaloptera are generally large insects, with members of some species having a wingspan of about 17 cm. Their prognathous head carries well-developed compound eyes, long multisegmented antennae, and chewing mouthparts [including enormously elongate mandibles in some male Corydalidae (Figure 10.1C)]. Three ocelli are present in Sialidae but absent in Corydalidae. The thoracic segments are well developed and freely movable; the pronotum is broad. All legs are similar. Four membranous wings occur, with all of the major veins and a large number of crossveins present. The wings lack

FIGURE 10.1. Megaloptera. (A) An alderfly, Sialis mohri (Sialidae); (B) Sialis sp. larva; (C) a male dobsonfly, Corydalus cornutus (Corydalidae); and (D) Corydalus sp. larva. [A, B, from H. H. Ross, 1937, Studies of Nearctic aquatic insects. I. Nearctic alderflies of the genus Sialis (Megaloptera, Sialidae), Bull. Ill. Nat. Hist. Surv. 21(3). By permission of the Illinois Natural History Survey. D, from A. Peterson, 1951, Larvae of Insects, By permission of Mrs. Helen Peterson.]

a pterostigma. The wing-coupling apparatus is of the jugofrenate type. The abdomen is 10-segmented and lacks cerci.

The structure of the internal organs is poorly known. The alimentary canal has a mediodorsal food reservoir; six or eight Malpighian tubules are present; the nervous system is primitive with three thoracic and generally seven abdominal ganglia; females have a varied number of panoistic (Corydalidae) or telotrophic (Sialidae) ovarioles.

Larva and Pupa. Larvae are elongate and in some species may reach a length of 8 cm. The prognathous head is well developed and carries chewing mouthparts. The thorax bears three pairs of strong legs, the abdomen seven (Sialidae), or eight (Corydalidae) pairs of gills. Pupae are decticous, exarate, and not enclosed in a cocoon.

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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