Phylogeny and Classification

When the first strepsipteran was described, in 1793, it was believed to be a hy-menopteran. In 1808 it was transferred to the Diptera, and in 1813 placed in its own order Strepsiptera. Since then, strepsipterans have been considered as a separate order having affinities with the Coleoptera, Diptera, or Hymenoptera, as a superfamily within the Coleoptera-Cucujiformia, and even as a family, Stylopidae, of lymexyloid beetles (some of which are heteromorphic). Kristensen (1981) even questioned the endopterygote nature of strepsipteran development. Though it is now generally accepted that the Strepsiptera deserve ordinal status, the highly polarized debate over whether the Coleoptera or the Diptera are the sister group continues vigorously (Kathirithamby, 1989; Kinzelbach, 1990; Kukalova-Peck and Lawrence, 1993; Whiting, 1998; Huelsenbeck, 2001). Those in favor of a Strepsiptera-Coleoptera sister-group relationship cite a number of common morphological features, as well as the similar life histories of Strepsiptera and the heteromorphic beetles. Supporters of the Strepsiptera-Diptera idea argue that the supposed similarities of beetles and strepsipterans are not synapomorphies but are simply the result of convergence. They offer other morphological, as well as molecular, evidence to support their case, sometimes even suggesting that the two orders should be combined in a superorder "Halteria," reflecting the purported similarity in structure and function between dipteran halteres and the reduced fore wings of strepsipterans (reviewed by Whiting, 1998).

Fossil Strepsiptera are known mainly from Eocene and Miocene ambers and, with one exception, are assignable to extant families. Only adult males, two male puparia in a poorly preserved host, and a single supposed triungulin in the gut of an elaterid beetle have been described (Kinzelbach and Pohl, 1994).

Kinzelbach (1990, and earlier) divided the order into two suborders and nine families, eight of which contain extant species.

Suborder Mengenillidia

In this suborder males are recognized by their five-segmented tarsi that end in a pair of strong claws but no sensory spots. Females (of extant species) are free-living, larviform insects, with eyes, legs, antennae, and a single genital opening.

The suborder includes two families, MENGEIDAE, known only from the male of one species (Mengea tertiaria) in Baltic amber, and MENGENILLIDAE (12 species), which are parasitoids of Zygentoma and occur in the Mediterranean area, Asia, and Australia.

Suborder Stylopidia

Males have two- to four- (rarely five-)segmented tarsi, with or without claws and sensory spots. Females are parasitoid, remaining within the host with only the anterior end of the body extruded; eyes, legs, and antennae are absent.

Almost one-half of the described species of Strepsiptera belong to the family STYLOP-IDAE (275 species), a cosmopolitan group whose hosts include vespid and sphecid wasps

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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