Phylogeny and Classification

The fossil record of Embioptera is poor. Some authors (e.g., Hennig, 1981; Kukalova-Peck, 1991) believe that it is a very ancient insect order with a fossil record that extends to the Lower Permian period. It is claimed that these fossil remnants have a combination of primitive (e.g., wings in females, multisegmented cerci, and short ovipositor) and advanced characters (e.g., asymmetric cerci in males and reduced wing venation). However, the "embiid" nature of these Permian fragments is disputed by other workers (e.g., Carpenter, 1992; Rasnitsyn and Quicke, 2002), so that genuine embiopteran fossils do not appear before the Late Cretaceous-Early Eocene. The order is clearly orthopteroid but its strongly apomorphic character has hindered clarification of its position within the larger group. Relationships with Plecoptera, Dermaptera, Phasmida, and Zoraptera have been suggested by various authors (see Kristensen, 1991).

Because of the neotenous nature of females, identification and classification using morphological characters can be carried out with certainty only by examining mature males. Ross (1970) recognized eight families of living Embioptera, but it is not yet possible to draw many conclusions regarding their phylogenetic relationships because of the general structural uniformity of the order and the amount of parallel evolution that has taken place among families. The northern South American and West Indian family CLOTHODIDAE is the most primitive group. In this family, to which certain Miocene fossils are assigned, the cerci of the male are symmetrical and comprise two smooth segments. The largest family, EMBIIDAE, is arather heterogeneous group of Old and New World forms. Szumik's (1996) cladistic analysis showed that, as presently constituted, the Embiidae is a paraphyletic group.

156 Another large and likely paraphyletic family is the OLIGOTOMIDAE, a rather prim-

chapter 7 ^e group with representatives in Asia, Australia, southern Europe, and possibly East

Africa. Three species of Oligotoma have been introduced accidentally into the United States. Other families are the AUSTRALEMBIIDAE (restricted to eastern Australia and Tasmania), NOTOLIGOTOMIDAE (Southeast Asia and Australia), EMBONYCHIDAE (East Asia), TERATEMBIIDAE (South America and southern United States), and ANISEMBIIDAE (Central America and southern United States).

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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