274 that is, the ventral side of the case is flat and composed of fine sand grains, and the dor sal surface is strongly convex and built of coarser material. When larvae are about to pupate, they cut away the ventral part of the case and fix the dorsal component to the substrate. Adult HYDROPTILIDAE (600 species) are hairy, minute Trichoptera (1.5-6 mm in length), often called micro-caddisflies, whose larvae are found in a variety of permanent waters worldwide. The larvae are of particular interest in that they exhibit hypermeta-morphosis (see Chapter 21, Section 3.3.2). The first four instars are active, free-living larvae that feed on algae and show very little growth. Nearly all growth occurs in the last, case-making instar, which is very different in appearance from its predecessors. In many species the case has a purselike shape, and members of the family are thus called purse-case makers.

Suborder Integripalpia

Between 20 and 30 families (depending on the authority) comprise this large suborder whose species have the following common features: adult maxillary palps with five segments (fewer in many males), the apical segment not annulate; females with separate anal and vaginal openings; larvae eruciform and mostly hypognathous, living in portable cases in which pupation usually occurs. Within the suborder, two major evolutionary lines can be seen, the limnephilid and leptocerid branches of Ross (1967), equivalent to the infraorders Plenitentoria and Brevitentoria of Weaver (1984). Within the Plenitentoria are the super-families Phryganeoidea and Limnephiloidea; in the Brevitentoria are the Sericostomatoidea and Leptoceroidea.

Superfamily Phryganeoidea

This group of fewer than 100 species mostly belong to the holarctic and oriental family PHRYGANEIDAE. The largest caddisflies are found in this family, with lengths up to 40 mm. Larvae usually construct cases ofleaf or bark pieces arranged in a spiral (Figure 9.24C) or in cylindrical sections glued end to end. The larvae are predaceous or detritus feeders found mainly in marshes and lakes, though a few species live in slow-moving streams or temporary pools.

Superfamily Limnephiloidea

By far the largest family in this group is the LIMNEPHILIDAE (1000 species) (Figure 9.24A,B), a primarily holarctic family of small to large caddisflies (7-25 mm in length). The larval case is built of plant or mineral material, its characteristics often being genus-specific. Larvae are found in moving or standing waters (including temporary and brackish pools) where they are typically detritus feeders, though a few scrape algae off rocks. LEPIDOSTOMATIDAE (250 species) are widely distributed though absent from Australia. Larvae live mainly in cool, slow-moving waters, occasionally in the littoral zone of lakes, where they feed on detritus. The BRACHYCENTRIDAE (100 species) are confined to the holarctic and oriental regions where they occur in a variety of cool, moving-water habitats. Larvae of most species are algivores; however, a few species are predaceous, using their long, spiny legs as filters with which to trap passing insects.

FIGURE 9.24. Integripalpia. (A) Limnephilus indivisus (Limnephilidae) larva; (B) L. indivisus case; (C) Phry-ganea cinerea (Phryganeidae) case; (D) Helicopsyche borealis (Helicopsychidae) case; (E) Triaenodes tarda (Leptoceridae) adult; and (F) T. tarda larva in case. [A-D, from G. B. Wiggins, 1977, Larvae of the North American Caddisfly Genera (Trichoptera). By permission of the Royal Ontario Museum. E, F, from H. H. Ross, 1944, The caddisflies, or Trichoptera, of Illinois, Bull. Ill. Nat. Hist. Surv. 23:1-326. 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.

Get My Free Ebook

Post a comment