Phylogeny and Classification

Like the Psocoptera, the Hemiptera are a very ancient group whose fossil record extends into the Lower Permian period. The earliest known Hemiptera are the Archescytinidae (Figure 2.9B) from the Lower Permian of Moravia (Czech Republic). These represent "stem-group" homopterans, close to but not within the Auchenorrhyncha, which appear slightly later. Sternorrhyncha and Heteroptera first appear in the fossil record of the Upper Permian. By the Upper Permian, the auchenorrhynchans were clearly divisible into Fulgoromorpha and Cicadomorpha, and fossils assignable to extant families have been obtained from Upper Triassic and Lower Jurassic deposits. Among the Sternorrhyncha, the Psylloidea and their sister group, Aleurodoidea, date from the Upper Permian, while the earliest Aphidoidea and Coccoidea occur in the Triassic. The Coleorrhyncha, whose fossil record extends back to the Lower Jurassic, share characters with both the Auchenorrhyncha and the Heteroptera, though the consensus is that they branched off the heteropteran line at an early date, perhaps even in the Permian. Some authors consider this group sufficiently distinct from other Hemiptera as to warrant the rank of suborder. In the Jurassic the Heteroptera underwent a wide radiation, and the comparatively rich fossil record from this period includes representatives of many extant families, especially Nepomorpha and Leptopodomorpha. Although some fossil Cimicomorpha have been obtained from the Upper Jurassic, this group and its sister group, Pentatomorpha, underwent a major expansion in the Cretaceous, paralleling the radiation of the angiosperms. A proposed phylogeny of the order is shown in Figure 8.4.

As noted in the introduction to this order, the traditional subdivision of the Hemiptera into Homoptera and Heteroptera is no longer tenable, the Sternorrhyncha now being considered the sister group to the rest of the Hemiptera (i.e., Auchenorrhyncha + Heteroptera, including Coleorrhyncha) (see Carver et al., 1991; Campbell et al., 1994; Sorensen et al., 1995; von Dohlen and Moran, 1995). Until recently, based on morphological criteria, it was widely accepted that the three suborders were monophyletic. Molecular studies have supported the monophyly of the Sternorrhyncha and Heteroptera, but strongly suggest that the Auchenorrhyncha is aparaphyletic group. Thus, Sorensen etal. (1995) proposed the division of Auchenorrhyncha into two suborders, corresponding to the Fulgoromorpha and Cicado-morpha of morphology-based classifications. Within the Heteroptera, eight infraorders are recognized in the classification used here (largely from Carver et al., 1991). Of these, the Gerromorpha correspond to the Amphibicorisae (amphibious bugs), the Nepomorpha to

FIGURE 8.4. A proposed phylogeny of the Hemiptera. [After M. Carver, G. F. Gross. and T. E. Woodward, 1991, Hemiptera, in: The Insects of Australia, 2nd ed., Vol. 1 (CSIRO, ed.), Melbourne University Press. By permission of the Division of Entomology, CSIRO.]

the Hydrocorisae (aquatic bugs), also known as Cryptocerata on the basis of their short, concealed antennae, and the Cimicomorpha + Pentatomorpha to the Geocorisae (terrestrial forms) of earlier systems.

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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