Pheromone glands contact pheromones

All life stages of the German cockroach produce 3,11-dimethylnonacosane, suggesting that production of a sex-specific contact pheromone may be less dependent on differentiation of sexually dimorphic pheromone glands, as is the case for volatile pheromones, and more so on the endocrine milieu of the adult female. Normally, adult male cockroaches produce much less JH III than do females, and males have a much lower titer of JH III in the hemolymph (Piulachs et al., 1992 reviewed in Tobe and Stay, 1985 Wyatt and Davey, 1996). However, when newly emerged males were exposed to filter papers treated with the JH mimic hydroprene they exhibited a six-fold elevation in female pheromone on their cuticle (Schal, 1988). Although substantial, this limited stimulation indicates... 

In recent years, there is only one example of a pheromone in solitary Apocrita being chemically identified. Chiral GC and chiral GC-EAD provided identification of (3S)-(+)-linalool 8 >99.9% e.e. as a mandibular gland mate attractant in both males and females of Colletes cunicularius. Male contact with a scented source could be initiated with 5 ng per lure (3S)-(+)-linalool, which may act as both a sex attractant and a food attractant [35]. 

Several long-range attractant sex pheromones have been identified (Table 3) or evidence for such a pheromone has been obtained in the past 13 years. The parasitoid Ascogaster reticulatus produces (9Z)-hexadec-9-enal 9 in a tibial gland [47]. The pheromone is spread by the females much like a trail on the substrate, and the males follow the mark to the source by close antennal contact with the substrate [48]. EAG studies have revealed that the males respond much more strongly to (9Z)-hexadec-9-enal than the females and that the response to the... 

The well-known boar pheromone was not only one of the first mammalian pheromones identified, but also the first one applied commercially. The saliva from the submaxillaiy gland contains two steroids. These are 5a-androst-16-en-3-one and So -androst-lS-en-So -ol (Fig. 7.8). They are emitted during head-to-head contact in courtship. Both individually stimulate the sow to assume the mating stance, but a mixture of the two is not more active than either compound (Melrose etal., 1971). This may be a case of adaptive redundancy. 

Figure 1. Courtship pheromone delivery in the terrestrial salamander R jordani. Pheromone delivery occurs while the pair are in the tail-straddling walk (Arnold 1976). The male turns back towards the female and brings his submandibular courtship gland (arrow) in contact with the female s nares. The female typically lifts her head so that pheromone delivery is facilitated.

Indirect delivery little contact with female. In some aquatic species, a male courts a female by relying on water currents to transport his pheromones to her. This describes courtship in Triturns and Cynops (Salamandridae). Excellent analyses by Halliday (1974, 1975, 1977) of the courtship of the smooth newt, Triturus vulgaris, show that the male moves his tail in a fan-like fashion to create a water current from the male s clocal glands towards the female s nares (see Halliday, 1975, Fig. 4). 

Fig. 16.16 Post-flight behavior of Trinervitermes bettonianus. (a) Female calling behavior, showing tergal glands and sternal gland exposed (b) Male following strong pheromone trail of female (c) Tandem run, with male in attennal contact with female (after Leuthold, 1975).

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