Chauliognathus

Defensive Compounds. The aposematically coloured Chauliognathusfallax which feed on Senecio brasiliensis (Asteraceae) sequester the four pyrrolizidine alkaloids senecionine (100 main compound), integerrimine (101 main compound), retrorsine 102, and usaramine 103 [203] (Scheme 11). Other Chauliognathus-species may contain either precoccinelline 104 and related alkaloids (C. pul-chelus) or Z-dihydromatricaria acid 105 (C. pennsylvanicus). 

The cantharid beetle Chauliognathus lecontei defensively secretes from glands in its thorax and abdomen droplets of liquid containing as a major fraction 8-ds-decene-4,6-diynoic acid (or 8-cis-dihydromatricaria acid) (Meinwald et al., 1968). Ultraviolet and mass spectral data quickly led to the identification of the chromo-... 

Many fatty-acid-derived acetylenic compounds in plants are active in plant-insect relationships. 8-Z-Dihydromatrica-ria acid, found in the defensive secretion of the soldier beetle (Chauliognathus lecontei), has been shown subsequently to have antifeedant properties against Phidippus spp. (jumping spiders) (Eisner et al., 1981). Matricaria acid (5) also has antifeedant properties against the pink bollworm, bollworm, and tobacco homworm (Binder et al., 1979). 

Eisner, T., D. Hell, M. Goetz, S. Jain, D. Alsop, S. Camizine, and J. Meinwald, Antifeedant action of Z-dihydromatricaria acid from soldier beetles (Chauliognathus spp.), J. Chem. Ecol., 7, 1149-1158 (1981). 

Other lysine-derived alkaloids known as coccinellines (42-47) occur in many members of the family Coccinellidae (ladybugs or ladybird beetles) (Fig. 29.15). Many of these insects are also wamingly colored. Cryptic members of the same groups usually do not contain the alkaloids (Jones and Blum, 1983). These alkaloids also have been isolated from a soldier beetle, Chauliognathus and from the boll weevil Anthonomus grandis. Coccinellines are highly repellent to... 

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