The Panorpoid Orders

several groups modified for sucking up liquid food. The head, pro- and mesonotum have 269

raised, wartlike areas that bear setae. The prothorax is small and ringlike; the mesothorax and metathorax are well developed. The legs are long and slender and have five-segmented tarsi. Two pairs of membranous wings are almost always present, though one or both pairs are greatly reduced in a few species. The wings are typically covered with fine hairs (denser on fore wings); however, these sometimes have a restricted distribution (e.g., along veins or in clumps) or are modified to scales. The fore and hind wings are coupled during flight. The wing venation is generalized and resembles that of some primitive Lepidoptera. There is in most species a whitish spot, the thyridium, devoid of hairs near the center of each wing. The wings are held rooflike over the body when not in use. Ten abdominal segments can be distinguished. In males the genitalia comprise a pair of claspers, a phallus usually with an extensile aedeagus and a pair of parameres, and various accessory structures derived from the 10th segment. In females of some species the terminal segments are retractile and function as an ovipositor.

Though not well known, the internal structure appears quite generalized. The gut is short and straight, and there are six Malpighian tubules. In the ventral nerve cord three thoracic and seven abdominal ganglia are found, the metathoracic and first abdominal ganglia having fused together. The testes are saclike; the ovaries contain numerous polytrophic ovarioles.

Larva and Pupa. Larvae are generally campodeiform (free-living and fixed-retreat species) (Figures 9.22 and 9.23) or eruciform (portable case-building species) (Figure 9.24). The head is well sclerotized and carries a pair of very short antennae, mandibulate mouthparts, and two lateral clusters of ocelli. The thorax is variably sclerotized and bears well-developed legs that have an unsegmented tarsus. The forelegs are fairly short and used more for holding food and constructing the case than for walking. The abdomen is 10-segmented. The first abdominal segment of most species of Limnephiloidea has three prominent, retractile papillae that bear sensory hairs; these may enable the insect to maintain its position in the case. Prolegs are absent on all but the last abdominal segment. These have a pair of strong hooks for anchoring the insect to the case or substrate. In a few species respiration is entirely cutaneous but most species have gills. These are usually simple filamentous structures developed on the abdomen, occasionally also on the thorax. Sometimes they are arranged in groups, or they may be branched basally. Blood gills (non-tracheated) occur in some species; they are usually eversible and have an osmoregulatory function.

Pupae are mostly decticous (adecticous in some Phryganeidae) and always exarate. They are aquatic, respiring by means of the larval gills or cutaneously, and have well-developed mandibles which the pharate adult uses to cut its way out of the case or 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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