Phylogeny and Classification

The modern consensus of opinion is that the Coleoptera were derived from some Megaloptera-like ancestor, probably in the early part of the Permian period. Evidence in support of this opinion was produced with the discovery of the Lower Permian fossil Tshekardocoleus (Protocoleoptera) whose elytral venation is intermediate between those of primitive existing Coleoptera and Megaloptera. The earliest undoubted beetle fossils are from the Upper Permian and belong to the suborder Archostemata, a few species of which survive to the present day. Fossil Adephaga, commonly aquatic forms, are known from the Lower Triassic, but Crowson (1960, 1981) suggested that the suborder is as old as the Archostemata. Though it appears possible that the earliest members of the suborder Polyphaga also evolved in the late Permian, fossils of this group are not known before the middle of the Triassic. Crowson (1960, 1981) speculated that a rapid radiation of the Coleoptera in the Jurassic led to the formation of three stocks: carnivorous Adephaga, wood-boring Archostemata, and Polyphaga (including the now separate Myxophaga). The Polyphaga was initially a small group of wood or fungus eaters that only later (in the Cretaceous) underwent a massive radiation correlated with the advent of the flowering plants. More than 80% of the world's species are included in this suborder. A suggested phylogeny of the Coleoptera is shown in Figure 10.6.

The classification of the order used here is based largely on that given by Crowson (1981). The suborder Archostemata is basal to the remaining suborders. Of these, the Adephaga is the sister group to the Myxophaga + Polyphaga. This arrangement is supported by the extensive analysis of Beutel and Haas (2000). However, the molecular study of Caterino et al. (2002), while supporting the basal nature of the Archostemata, had the Myxophaga as the sister group to the remaining two. In a recent extensive phylogenetic analysis, based on 63 hind wing characters, Kukalova-Peck and Lawrence (2004) have concluded that the Polyphaga is the sister group to the remaining Coleoptera, with the Archostemata sister to the Myxophaga and Adephaga.

Suborder Archostemata

Adult Archostemata have the following characters: wings with distal part coiled when at rest; hind wings with oblongum cell; notopleural sulcus present on prothorax; and hind coxae not immovably fixed to metasternum. Larvae have five-segmented legs with one or two claws and mandibles with a molar area. Urogomphi are absent.

Fewer than 30 species of beetles are contained in this suborder, all of them in the superfamily Cupedoidea. Three families are recognized. OMMATIDAE (six species) occur in Australia, South America, and Italy. CUPEDIDAE (21 species) are found on all continents and most large islands. Adults are short-lived and some feed on pollen; larvae are long-lived and bore in fungus-infested wood. The MICROMALTHIDAE includes only one species,

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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