Numerous cockroaches broadly similar to those living today existed in the Carboniferous period, some 300 million years ago. The fossil record, including probable oothecae, is especially strong from the Upper Carboniferous onward from many regions of the world, and by the Paleocene species assignable to modern families occurred. Opinions differ on when the mantid and cockroach lines diverged. At one extreme, Carpenter (1992) suggested that the mantids may have evolved independently, from protorthopterous ancestors. In contrast, Rasnitsyn and Quicke (2002) indicate an evolution from a polyphagid cockroachlike ancestor in the Late Triassic. The earliest mantid fossils come from the Early Cretaceous, though these are generally only wing or foreleg fragments. By the Eocene, the group was well established; indeed, some fossils from this period can be placed in modern families.

Attempts to interpret the phylogeny of the suborder Blattodea have been hampered by the high degree of parallel evolution that has occurred within the group. McKittrick (1964) examined the external genitalia, oviposition behavior, and crop structure in a wide variety of extant species. She suggested that cockroach evolution proceeded along two lines, one leading to the superfamily Blattoidea (families Cryptocercidae and Blattidae), the other to the superfamily Blaberoidea (families Polyphagidae, Blattellidae (= Ectobiidae), and Blaberidae). Durden's (1969) study of Carboniferous cockroaches generally supported McKittrick's conclusions, though he recognized several additional superfamilies. More recent proposals have been based on extensive cladistic analysis of morphological and anatomical features of extant species (Grandcolas, 1996), mDNA sequences (Maekawa and Matsumoto, 2000), and fossils (Rasnitsyn and Quicke, 2002). Taken together, these studies show that the Blattidae and Cryptocercidae are not sister groups, the Polyphagidae and Cryptocercidae are closely related, and the Blattidae are the sister group to the Blattellidae + Blaberidae. A proposed phylogeny is shown in Figure 7.5.

Classification of the suborder Mantodea is also difficult because of parallel evolutionary trends among the constituent groups. Beier (1964) divided the suborder into eight families, contained within the single superfamily Mantoidea, of which the Amorphoscelidae and Mantidae are the largest. The six remaining families are small, tropical groups of restricted distribution.

the plecopteroid, blattoid, and orthopteroid orders



FIGURE 7.5. Proposed phylogeny of Blattodea.






- Blattidae

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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