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1	Author	Claudia Schütz, K. Onrad Dettner	Requires cookie*
	Title	Cantharidin-Secretion by Elytral Notches of Male Anthicid Species (Coleoptera: Anthicidae)
	Abstract	Within the beetle family Anthicidae or ant-like flower beetles the canthariphilous species N o to x u s m onoceros shows a pair o f notch-like structures on the apices o f male elytra. A reser voir-like swelling at the apex o f each elytron contains a bilobed gland. Its glandular tubules run into the sclerotized notch. Gaschromatographic investigations o f elytral notches and the testes o f cantharidin-fed and unfed male N o to x u s m onoceros revealed huge quantities o f can tharidin stored in these organs in fed specimens. Other body parts, such as legs, elytral parts or flight muscles, had low cantharidin-titres, both in cantharidin-fed and unfed beetles. The can-tharidin-titres o f unfed individuals were very low compared with cantharidin-fed specimens, although cantharidin was present, mostly in notches. During sexual display the females bite several times into these notches and easily copulate, if the males had access to offered canthari din crystals. Thus, the elytral notches o f male N o to x u s m onoceros seem to function as "test-organs" for females which are able to select males with high cantharidin loads prior to copula tion. Even small quantities o f cantharidin stored in notches o f field caught specimens seem o f advantage for males in competing for a female partner.
	Reference	Z. Naturforsch. 47c, 290—2 (1992); received September 13 1991/January 12 1992
	Published	1992
	Keywords	Cantharidin, Elytral N otches, Sexual Selection, Anthicidae, Coleoptera
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	TEI-XML for	default:Reihe_C/47/ZNC-1992-47c-0290.pdf
	Identifier	ZNC-1992-47c-0290
	Volume	47

2	Author	C. Holz, G. Streil, K. D. Ettner, J. D. Ütem Eyer, W. Boland	Requires cookie*
	Title	Intersexual Transfer of a Toxic Terpenoid during Copulation and Its Paternal Allocation to Developmental Stages: Quantification of Cantharidin in Cantharidin-Producing Oedemerids (Coleoptera: Oedemeridae) and Canthariphilous Pyrochroids (Coleoptera: Pyrochroidae)
	Abstract	In whole body extracts of the canthariphilous pyrochroid Schizotus pectinicornis and the cantharidin-producing oedemerid Oedemera femorata cantharidin contents were determined by means of quantitative gas chromatography. Adults and all developmental stages of both species contain this terpenoid, but in considerably different amounts. Cantharidin contents differ significantly between the sexes of adult O. femorata: 8.4 \|j,g/female, 3.5 (.ig/male. Values for Sch. pectinicornis are more than 30-fold lower than those of O. femorata and no inter-sexual difference in the cantharidin content could be detected. Eggs of O. femorata contained cantharidin and larvae of this species are capable of synthesizing this terpenoid. The total amount of cantharidin increases in successive instars. In Sch. pectinicornis, the content of cantharidin decreases from egg to first instar. Feeding and copulation experiments with [2H2]cantharidin indicate that in O. femorata no or only very small amounts of cantharidin are transferred from males to females at copu lation. Thus, males do not invest in the protection of their offspring by cantharidin gifts to the mate. For Sch. pectinicornis an intersexual transfer of labelled cantharidin during copu lation was detected. About 45% of the entire cantharidin content in mated females derived from fed males. Analyses of eggs and first instar larvae show that a paternal allocation of 2[H2]cantharidin to developmental stages exists for this canthariphilous pyrochroid.
	Reference	Z. Naturforsch. 49c, 856—864 (1994); received April 27/August 3 1994
	Published	1994
	Keywords	Intersexual Transfer, Paternal Allocation, Cantharidin, Oedemeridae, Pyrochroidae
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	TEI-XML for	default:Reihe_C/49/ZNC-1994-49c-0856.pdf
	Identifier	ZNC-1994-49c-0856
	Volume	49