Paleoptera

evolved. One led to the suborder Carapacea, the other to the suborders Furcatergalia, Setisura (which are sister groups) and Pisciforma. Though relationships of the families in the first three suborders are reasonably clear, those for the Pisciforma remain to be established.

Suborder Carapacea

Members of the Carapacea (an allusion to the carapacelike enlargement of the larval mesonotum) are included in a single superfamily Prosopistomatoidea.

Superfamily Prosopistomatoidea

The two small families in this group, the BAETISCIDAE [12 North American species of Baetisca (Figure 6.3)] and PROSOPISTOMATIDAE (11 species of Prosopistoma with a wide distribution including Africa, Australia, Europe, and southern Asia), show considerable parallel evolution in the larval stage. Indeed, their larvae are remarkable in having an enormous, posteriorly projecting mesonotal shield that protects the gills so that they superficially resemble notostracan crustacea, into which group Prosopistoma was originally placed by the French zoologist Latreille in 1833 (Berner and Pescador, 1980). Larvae of most species live in moving water, from streams to large rivers, where the bottom has sand, fine gravel, or small stones. Adult baetiscids, which are medium-sized insects, have an unusually large mesothorax; the eyes of males are large and almost contiguous but not divided horizontally. Prosopistomatid adults of both sexes have small, widely separated eyes; males have relatively short forelegs; the legs of females are vestigial; and females do not have an adult molt.

Suborder Pisciforma

McCafferty (1991) introduced the suborder Pisciforma (the name refers to the minnowlike body and actions of the larvae) for a group of families whose relationships remain unclear. For this reason, no arrangement into superfamilies is undertaken, though in earlier

FIGURE6.3. Larva of Baetisca bajkovi (Baetiscidae). [FromB. D. Burks, 1953, The mayflies, or Ephemeroptera, of Illinois, Bull. Ill. Nat. Hist. Surv. 26(1). By permission of the Illinois Natural History Survey.]

FIGURE 6.4. Larva of Baetis vagans (Baetidae). [From B. D. Burks, 1953, The mayflies, or Ephemeroptera, of Illinois, Bull. III. Nat. Hist. Surv. 26(1). By permission of the Illinois Natural History Survey.]

schemes the families were lumped in a single superfamily Baetoidea. Only the major families are outlined here.

The SIPHLONURIDAE is a fairly large, probably paraphyletic, family containing about 160 described species with a worldwide distribution but especially diverse in the holarctic region. The streamlined, active larvae are found on the bottom of fast-flowing streams or among vegetation in still-water habitats. Some are predaceous. Adults are medium- to large-sized mayflies, and the sexes are similar in coloration. In both sexes the compound eyes are large and have a transverse band dividing the upper and lower regions. In males the eyes are usually contiguous.

The BAETIDAE (Figure 6.4) is easily the largest family of Ephemeroptera (>500 species) and has a worldwide distribution. The torpedo-shaped larvae are found in a variety of habitats but commonly on the bottom of fast-flowing streams where they may be well camouflaged. Adults are generally small and sexually dimorphic. The hind wings are greatly reduced or absent. The compound eyes of males are large and divided horizontally into distinct parts; in females the eyes are small and simple.

Suborder Setisura

Included in this suborder are the families listed under the superfamily Heptagenioidea in older classifications. The major family is the HEPTAGENIIDAE (Figure 6.5) which ranks next to the Baetidae in terms of number of described species (380). Heptageni-ids are an almost entirely holarctic and oriental group and are not represented in the Australasian region. The generally darkly colored larvae are typically found clinging to the underside (occasionally the exposed face) of stones in fast-flowing streams and on wave-washed shores of large lakes. They are remarkably well adapted for this life. Their body is extremely flattened dorsoventrally; the femora are broad and flat; the tarsal claws have denticles on the lower side; the gills are strengthened on their anterior margin; in some species the entire body takes on the shape (and function) of a sucking disc. Some larvae have fore tarsi with numerous setae that filter algae, etc. from the water and give the

FIGURE 6.5. Larva of Heptagenia flavescens (Heptageniidae). [From B. D. Burks, 1953, The mayflies, or Ephemeroptera, of Illinois, Bull. Ill. Nat. Hist. Surv. 26(1). By permission of the Illinois Natural History Survey.]

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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